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  • CONSEIL PERMANENT INTERNATIONAL POUR L'EXPLORATION DE LA MER

    CHARLOTTENLUND SLOT- DANEMARK

    ANNALES BIOLOGIQUES VOLUME NO. III

    REDIGE PAR

    H. BLEGVAD AVEC L'AIDE DE

    AA. J. C. JENSEN

    1946

    EN COMMISSION CHEZ

    ANDR. FRED. H0ST & FILS COPENHAGUE

    Prix: Kr. 12.00

    Mars 19~3

  • Corri~enda Ann. Biol. Vol. II, Table 5, p. 64.

    Plaice Sole

    Month < 25 ern. < 25 CUL !9~!} j().j.!}

    in8ff'ad of I"f'

  • -3-

    TABLE OF CONTENTS

    Reports

    North-Eastern Area

    The Fish: The Arcto-Norwegian Stock of Cod - Gunnar Rolle f sen

    North-Western Area

    Introduction, by A. V. Tan in g

    Page

    7

    9

    Environment. Hydrography (Faroe-Shetland Channel) - J ens S me d...... lO (North-Western North Atlantic)- J ens S me d 12

    The Fish. Faroes. Lemon Sole- B. B. Rae ....................................... 24 Iceland. Larval Herring- A. V. Tan in g ........................... 25

    Atlantic Slope

    Introduction, by J. l e G a ll . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

    The Fish. Hake - R. Let a conn o u x................. .. . . . . .. . . . . .. . . . . . . . . . . . . . . 28 Plaice - R. L e t a c o n n o u x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Megrim - D i z e r b o, Forest and Let a conn o u x............ 31 Herring - G. P. Farran .. .............................................. 33 Sardine - R. L e t a c o-n n o u x.......................................... 33 Anchovy - R. L e t a c o n n o u x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Mackerel - R. L e t a c o n n o u x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Lesser Silver Smelt - R. L e t a c o n n o u x........................... 36 Grey Gurnard - R. L e t a c o n n o u x and F o r e s t............... 37

    Northern North Sea

    Introduction, by R. S. C l a r k . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

    Environment. Hydrography (Northern Entrance to the North Sea) -}ens Smed ..................................... 40

    (Scottish Waters) - John B. T a it ............ 42 Plankton - J. H. F r a s e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

    The Fish. Lemon Sole - B. B. R a e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Herring (Fladen and Gut) - C h. Gil is . . ...... ...... .. ... . ... .. . .. .. 45

    (Western North Sea) - A age J. C. Jensen............ 48

  • -4-

    Southern North Sea Page Introduction, by R. S. W i m p e n n y 51

    Environment. Hydrography - He l g e Thomsen.............................. 52

    The Fish. Plaice (The open North Sea) - A age J. C. Jensen . . .. . .. . .. .. 52 (S. North Sea and Channel) - R. S. Wimp en n y .... .. 57

    Demersal Seafish (Dutch Fishery) - L. K. Boer em a and W. Ro s ..................................................................... 75

    Herring (East Anglian) - W. C. Hodgson ........................ 79 (S. North Sea and Channel) - J. An c e IIi n............ 81 (Spent)- Ch. Gilis .......................................... 84

    Transition Area Introduction, by E. M. P o u l s en...................................................... 89

    Environment. Hydrography (L. V. "Anholt Knob" and "Halskov Rev") -He l g e Thomsen . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . 91

    (at Flji>devigen) - A l f Dan nevi g............ 92 Benthic Food - E. M. Po u l sen.................................... 92

    The Fish. Gadidae - A l f D ann e v i g............................................. 93 Plaice (Abundance of Year-Classes) - A age J. C. Jensen . . . 93

    (Commercial Catches) - A age J. C. Jensen............ 96 (In the Limfjord) - E. M. Po u l sen........................ 96 (Transplantations) - E. M. P o u I s e n........................ 96 (Anal Fin Rays) - E. M. Po u l sen . . .. . . . . . . . .. . . . . . . . .. . . 98

    Dab - E. M. Po u l sen................................................... 99 Herring (Danish Investigations) - A age J. C. Jensen......... 99

    (Fladen Herring at the Skaw) - K. A. A n d e r s s o n... 102 Eel - E. M. P o u l s en . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 Fish for Processing - A age J. C. Jensen ........................ 103 Lobster - E. M. Po u l s en, A lf D anne vi g ..................... 104 Oysters - A l f D an e vi g................................................ 104

    Baltic Area Introduction, by K. A. Andersson ................................................ 105

    Environment. Hydrography (at Bornholm) - A age J. C. Jensen ......... 106 (during 1945/46) - H. Aland e r ............... 106 (off the Polish Coast) - A. Glow ins k a ... 108

    Plankton (Macroplankton in the Gulf of Gdansk) -W. Mankowski .................................... llO

    (Phytoplankton in the Gulf of Gdansk) -Ann a Rum e k ....................................... 110

    The Fish. Cod (Polish Investigations) - F. Chrzan ........................ lll (Swedish Trawling) - H. A Ian de r ........................... lll

    Flat-Fishes (The 0 and I-Group) - A age J. C. Jensen, A. M o Ian de r .......................................... 113

    Flounder (Gulf of Gdansk) - Z. M u lick i ........................ ll3 Herring (Bornholm) - A age J. C. Jensen ........................ ll4 Garfish (Reproduction and Development) - K. De me I ......... ll5

  • -5-

    Resume of Subjects.

    Environment. Hydrography: NW-A., Faroe-Shetland Channel, p. 10; NW North Atlantic, p. 12; NNS, p. 40; SNS, p. 52; Tr. A. p. 91; Baltic, p. 106.

    Plankton: NNS, p. 43; Baltic, p. llO. Benthic Food: Tr.Area, p.92.

    The Fish. Demersal Seafish: SNS, p. 75. Gadidae: Tr. Area, p. 93. Cod: NE-A., p. 7; Baltic, p. 111. Hake: Atl. Sl., p. 28. Plaice: Atl. Sl., p. 30; SNS, p. 52; Tr. A., p. 93; Baltic, p. 113. Dab: Tr. A., p. 99. Flounder: Baltic, p. 113. Lemon Sole: NW-A. (Faroes), p. 24; NNS, p. 44. Turbot: Baltic, p. 113. Megrim: Atl. Sl., p. 31. Herring: NW-A (Iceland), p. 25; Atl. SL; p. 33; NNS, p. 45;

    SNS, p. 79; Tr. A., p. 99; Baltic, p. 114. Sardine: Atl. Sl., p. 33. Anchovy: Atl. Sl., p. 34. Mackerel: Atl. Sl., p. 35. Grey Gurnard: Atl. Sl., p. 37. Garfish: Baltic, p. 115. Lesser Silver Smelt: Atl. Sl., p. 36. Eel: Tr. Area, p. 103. Fish for Processing: Tr. Area, p. 103. Lobster: Tr. Area, p. 104. Oyster: Tr. Area, p. 104.

  • -6-

    so lj{)"

    50

    30 zoo

    oo

    The Areas and their Limits. For the Transition Area see also the Map on p. 90.

  • -7-

    North-Eastern Area.

    The Arcto-Norwegian Stock of Cod. By

    Gunnar Rollefsen.

    Length Measurements. Samples of skrei or Lofoten cod, i.e., the sexu-

    ally mature component of the Arcto-Norwegian stock of cod, have been taken every year since 1913, and their length measured. These length measurements have proved to be of very great im-portance for the understanding of the variations to which the size composition of the stock' is subjected. By presenting the frequency values of the measure-ments in every single year as deviations from the mean value of the measurements taken throughout a series of years 0 s c a r S u n d could in a most convincing manner show the most outstanding peri-ods of recruitment. This is clearly demonstrated in Figure 1, where all measurements since 1913 are set off as deviations from the mean value of the measurements 1913-1945.

    When the work was started in 1913 we were apparently in a period of strong recruitment. The age analyses carried out showed a strong group of ~ 9-year-old fish, i.e., fish born in 1904. In 1919 this wave of recruitment, was exhausted, but in this same year the first faint signs of a new wave were noticeable. Simultaneous age investigations show that it is the year-class 1912 which makes its appearance.

    In 1925 a new recruiting period sets in. This time it is the three year-classes 1917, 1918, 1919 which appear in conjunction, and all three year-classes are very numerous.

    The next recrmtmg period, as we can clearly see, starts in 1937. It is mainly made up of the year-classes 1929 and 1930. Finally we have the present period which started in 1944 when the year:class 1937 occurred in noticeable numbers.

    Age Analyses. J?efore 1932 the age_ analyses were made from

    fish scales, but since 1932 the reading of otoliths has been the basic method. The individual samples collected for age determination are comparatively large, and the picture we obtain of the development of the various year-classes gives a solid impression. Every year-class seems to have a regular fate.

    In Figure 2 some heavy oblique lines are drawn so that we may follow a certain year-class through the different years. The oblique line in the middle traces the year-class 1930 through 10 years of its life, i.e., the time we have been able to follow it. This year-class occurs for the first time as 7-year old skrei in 1937. It is the leading group of the stock in 1940. In 1943 it must resign the leader-ship to the year-classes 1933 and 1934, both of which are above average. But they in turn are considerably outnumbered by the strong year-class of 1937 which dominates the stock from 1946 on-wards. And we must -expect that the year-class 1937 will continue to dominate during some years to come.

  • 50cm.60 80 100 110

    -8-

    120

    Fig. l. The Length Measurements presented as deviations from the average length distribution and showing the waves of recruitment.

    1935

    1936

    1937

    1938

    1939

    1940

    1941 1

    1942 -j

    1943

    1944

    1947

    Fig. 2. The Age Distribution of Skrei.

  • -----------~---------------------

    -9-

    North-Western Area.

    INTRODUCTION.

    T HIS year again, reports from members of the committee are characterised by the lack of continuous field research in the remote northern waters, difficulties in obtaining adequately equipped research vessels and also by shortages of personnel, laboratory facilities, gear and instru-ments. Obviously it will take several years before normal procedure is attained. Most of the members of the North-Western Area Committee refer to one or more of these difficulties as the immediate cause of their inability to contribute to the year's report. The lack of skilled personnel seems to be parti-cularly serious.

    As a result of the above, our knowledge of the age composition, strength of the various year broods, growth-rates, etc., for the stocks of almost all fish in the North-Western Area is at present negligible. A bright side in the situation is however evident

    from remarks made by various members, pointing out that they have obtained material on some stocks of important fishes, during the war and the post-war period. This material is to be worked up later, when time permits and more personnel is available.

    Our knowledge of the physical factors affecting fish and other marine organisms is regrettably low, since practically no observations have been made during six years.

    As seen from this report the routine work in the area was recommenced in 1946; and Mr. J ens S m e d has continued his useful retrospect of monthly anomalies of the surface temperature in the North Atlantic.

    At present it is, however, impossible to furnish particulars on the actual general conditions regard-ing stocks of fish, plankton and hydrography in the North-Western Area.

    A. V. TUning.

  • - 10-

    HYDROGRAPHY.

    Hydrographic Conditions in the Faroe-Shetland Channel in August 1946. By

    Jens Smed.

    D DRING August 26th and 27th, 1946, the Danish research vessel "Dana" under the leadership of Dr. .A. V e de I Tan in g undertook hydrographic investigations along a section across the Faroe--Shetland channel (see Fig. 1). The data will be published in the Bulletin Hydrographique pour les annees 1940-1946. A section showing isotherms and isohalines is given in Fig. 2. The positions of the stations are marked by vertical lines. Above each such line is indi-cated the number of the station, its position and the date when it was worked.

    For an account of the normal conditions in the Faroe--Shetland channel the reader should refer to the investigation by Jacobsen (1943), where the section here in question is designated "Section II". The paper gives inter alia the mean conditions in this section for the latter three quarters of the year.

    On the basis of the temperature and salinity data illustrated by Fig. 2 dynamical calculations were carried out in order to find the current velo-city and the water transport through the section. The values of the velocity perpendicular to the section are given in the diagram Fig. 3 for the various intervals of depth between the stations. Positive values indicate that the current has a north-erly direction. The values are based on the sup-position that the zero-surface - i.e. the surface where the horizontal pressure gradient equals zero - for an interval between two stations is situated as shown by the bottom line of the interval in the diagram. That means that the zero-surface for the interval is supposed to coincide with the isobaric surface at the bottom of the station with the smal-lest depth.

    Just below the bottom line in Fig. 3 are for

    Fig. l. Location of stations.

    each interval recorded two values for the intensity of the water flow through each interval in question. The upper one is in accordance with the stated cur-rent velocities. The lower value is found from the supposition (J a c o b s e n, loc. cit.) that the zero-surface coincides with the isobaric surface at 800 rn.

  • ' ~ ~.,

    0 = ~ ~

    ~-~.~

    Meter

    DaM21 27. VIII

    o151'N. 521' w.

    35.2

    Da 6420 27.Vlll

    6146'N. 446'5 w.

    Da6419 27. VIII

    61032'5N. 415' w.

    - 11

    Da 6418 26.VIII

    6J025'5N. 343' w.

    Da 6417 26.VIII

    61 OJ9'N. 3ll'W.

    Da 641o 26.Vlll

    6113'N. 240' w.

    Da 6415 26.VIII

    6107' N. 211 1 W.

    DaM14 26.VI!l

    61000' N. 137'W.

    Horizontal scale

    NW-Area Hydrography

    Da 6413 26.VIII

    60053' N-1005' w.

    20 30 naut.miles

    Fig. 2. Section giving isotherms and isohalines.

    and, with the bottom for depths less than 800 m. The value for the interval between the stations Da 6415 and Da 6416 is strongly influenced by the new supposition.

    It is seen from Fig. 3 that the main inflow takes place in the south-eastern part of the channel. This is a general feature. The figure shows that during the time of the investigation an inflow also took place in the western part of the channel, whereas there was an outflow in the middle of the channel.

    The two values for the flow through the whole section are recorded under "Total" in Fig. 3. Evi-dently the lower value should be regarded as the more accurate. This value too should, however, be taken with some reserve as it is rather uncertain if 8QO m. is the actual depth of the zero-surface. On

    the other hand the value may be thought to give at least the correct order of magnitude of the inflow.

    As to the current velocity, the correb.tion in-volved by the new zero-surface is only of real im-portance in the interval Da 6415 to Da 6416. In this interval the velocity values indicated in Fig. 2 should be augmented by about 17 em./ sec. to be in accordance with the new supposition as to depth of the zero-surface.

    Literature. Bulletin Hydrographique pour les annees l 9 4 0- l 9 4 6. In preparation.

    Jacobsen 1943. Rapp. et Proc.-Verb. CXII, p. 5.

  • - 12-

    Meier 0

    Farce-islands

    Da 6421 Da6420 Da6419 Da64i8 Da6il17

    Shetland-island5

    Da 6416 Va 6415 DaM14 DaM13

    1 ~;;:_ -2~~ 16~~c: -9~:'~ 0 ~;;; 17m ocm. 2 ~;;;. I sec 100 200

    0" Qn 15 -9 " 0 .. 15 " 0.2 ~:~: 1)

    0 0 km. 01 km.3 V hour Y 0.3" ~

    hour -0.3 ~:; !J 0.9 " ~

    0.1 " y 14 .. -8" 0 " 12 " -2.0 " ?.' 300

    11 .. -6" -1 " 8 " 400

    500

    3 " 6 " -Lj" -1 " 54 km.3 !!

    hour

    15.0 " ?J 3 .. -2 " -1 600

    700

    { 8 2 krn.; !J 1 " Total 17.2 h:v~ g) -1 . 0 ,,

    800 75 krn~ I

    hovrj)

    7.6 ,, g)

    900 Q n 0

    1000 0.

    -03k"'3JJ hour

    1100 -0.3 " ~ - km.3 1

    1200

    Fig. 3. Current and intensity of flow through the various parts of the section. The figures marked l) are the uncorrected, the figures marked 2) the corrected values.

    Monthly Anomalies of the Surface Temperature in some Areas

    of the North-Western North Atlantic in 1876-1939 and 1945-1946. By

    Jens Smed.

    As it may be of interest to the fishery biologist to know the variation of the temperature in an area during a period of some length, the following survey is given of the surface tempera-tures in some areas of the north-western North Atlantic during the years 1876-1939.

    The material has been collected by the Danish Meteorological Institute from vessels crossing the North Atlantic. For the period 1912-1939 the material was published in the relevant issues of the Nautisk-Meteorologisk Aarbog as means for the various 1 -squares. These means have 1een used

  • - 13

    directly in the present investigation. For the period 1876-1911 monthly means were most kindly placed at our disposal by H e I g e T h o m s e n, Head of the Nautical Section of the Danish Me-teorological Institute.

    The procedure in working up the material was the following. The temperature anomaly for each l 0 square and for each month was computed on the basis of the monthly mean values for the period 1876-1915, published by Ryder (1917). Then the anomalies were averaged over the areas C, D and E shown in Fig. l, viz. C: 60-66 N., 30-40'? W.; D: 55-60N., 30-40 W. and E: 50 -55 N., 30-50 W. By this averaging due regard was taken to the weight - indicated by the number of observations - of the means for each l 0 -square. For further details concerning the procedure the reader is referred to an earlier paper (Smed, 1947).

    In Tables l, 2 and 3 respectively are recorded the resulting average anomalies (11) for the areas C, D and E as well as the numbers (n) of observa-tions on which these average anomalies are based1 ). For area C the material contained no observations from the months January and February. A graphi-cal representation of these anomalies for the areas C and D is given in Fig. 2, for area E in Fig. 3.

    Fig. 2 shows a high degree of conformity between the variations in the surface temperature in the areas C and D. Rather conspicuous is the predominance of positive anomalies in these areas in the 1930's and - to a minor degree - in the 1920's. Obviously the increase in the surface tem-perature which is known to have occurred at many other localities also appears in these waters. For area E (see Fig. 3), however, the increase in tem-perature is in any case not very pronounced.

    For the areas A: 55-70 N., 50-58 W. and B: 55-63 N., 40-50 W. (see Fig. 1.) the increase in temperature was studied in a previous paper (S me d, loc. cit.), where monthly mean anomalies for each of these areas were given in tables. A graphical representation of the results was given with special regard to the possibility of following the variation of temperature from year to year for each month separately. For the marine

    1 ) The figures relating to the period 1876-85 have been omitted from Table 1.

    NW-Area Hydrography

    biology it may, however, be of use also to have a graph giving directly the variation of the tempera-ture anomaly from month to month comparable with Figs. 2 and 3 above. It was, therefore, found

    I s5m++-r+++H-+++t-i-++m1++-. t-1 r+++t-i-+++H-++++-l-l-l-4-l-ls5

    I I . i

    Fig. l. Location of the areas considered.

    advisable to give an analogous representation of the results for the areas A and B. This is done in Fig. 4. For further discussion of these results the reader is referred to the paper cited.

    Unfortunately no observations from the war years are at disposal. For the last half of 1945 and for 1946, however, some observations are published in the Nautisk-Meteorologisk Aarbog. On the basis of these observations we have comp-uted monthly mean anomalies for the areas A, B, C, D and E. The results are recorded in Table 4.

    Literature. N aut is k Meteor o 1 o g is k A arb o g (Naut.-Meteor.

    Annual) 1912-1939, 1945-1946. K0benhavn 1913-1940, 1946-1947.

    Ryder 1917. Monthly Mean Temperatures of the Surface Water in the Atlantic, North of 50 N. Lat. (App. to Naut.-Meteor. Annual). Copenhagen.

    S me d 1947. Annales Biologiques II, p. 17.

  • -14-

    -11':':::::~:::..- .. -2 f-

    1893 2f- 1891 1592 ( ... 1 r- r"'". ,\ ... . '.".~~/'-.../;/'\,/\,. o.-->f"'"':.: ........ \/---J '

    -1 v

    - ., ''-- /'"?' ... -.. .. ' L.~~

    1894

    -

    -

    1895 -

    _ ..... --

    -2~--~~----~----~~--~----~~----~----~~---+----~~--~-2 1896 .. 1897 ' 1898 1899 1900 -I~ !

    ~ _. . "\..__.,_ /'""', /' I . .- -- . """"""\. ,/ -.. ,---, /\ 0, . . ,' -- ... '-\,". ,;--~--. :-.. ... _,_. \ .. - .. , . } ' _d_-,\_ .. / '

  • - 15- NW-Area Hydrography

    tJFMAMJJASONDJFMAMJJASONDJFMAMJJASONDJFMAMJJASONDJFMAM 2 1911 1912 1913 1914 1915 1 0

    -1

    -2~--~~--+---~~---r--~~--~----~~--~--~~--~ 2 1916 1917 1918 1920 1 o~~~~~~~~~---+~~~~~------~--~~--~~~~~--~~

    -1 ' .' -2~--~~--~--~~--~----~~--~---==----+----~~---z. 1921 1922 1923 1925 1 o

    -1 -2 2~~,-, --~1~92~6~---r--~1~92~7~--~-1~92~8~,,----~.-:-.->-.~~19~29~/~~, __ _, ____ ~1~93~0~~

    \ ... ~/\ p~~AJ>~\ ,_j \/ \ __ ... ;~ \; \ / ....... __ ,

    -1

    \ I I I \I ,,

    I ' I I I I ,, '

    , .. . j

    ' I .; v

    ,,

    -2 ~J~F~M~A~M~J~J~A~S~O~N~D~J~F~M+A~M~J~J~A~S~O~N~D~J~F7M~A~M~J~J~A~S~O~N~D~J~F~M~A~M+J~J~A~S~O~N~D~J~F~M~A~M~J~J~A~S~O~N~D

    during the years 1876-1939. Solid lines: area C; dashed lines: area D.

  • - 16-

    'C J F M A M J J A S 0 N D J F M A M J J A S 0 N D J F M A M J J A S 0 N D J f M A M J J A S 0 N D J F M A M J J A S 0 N D 1876 1877 1878 1879 1880

    ... ~--- . .. - ....

    1B81 1882 1883 18M 1885

    19 3 1904

    JFMAMJJASONDJFMAMJJASONDJFMAMJJASONDJFMAMJJASONDJFMAMJJASOND Fig. 3. Monthly anomalies of the surface temperature

  • -----------------------~-----

    - 17 - NW-Area Hydrography

    "CJFMAMJJASONDJFMAMJJASONDJFMAMJJASONDJFMAMJJASONDJFMAMJJASOND 2 1911 1S12 1913 1914 1915 1 o~=A~--~~+-~~-----~------~---M----~----~~-----=~~

    -1 -2 2~---==---~----~=---~~--~~--~--~~----+---~19~2~0--~

    1 on-~~--~~7T+-----~-+----~-----r~~~~~+---~--~-4

    1939

    -1 --...

    -2 ~J~F~MhA~MTJ~JrAr5~0trN~O'J7F~M~A~MhJ~J~A~S~O~N~07J~F~M~A~MhJ~J~A~S~O~N~D7J~F~M~M~J~J~A~S~O~N~D~J~FMA

    1

    MJJASONO

    in the area E (see Fig. 1) during the years 1876-1939.

  • - 18-

    ~JFMAMJJASONDJFMAMJJASONDJFMAMJJASONDJFMAMJJASONDJFMAMJJASONO

    2 1876 1877 1878 1879 18\?Q, -

    1 ~ ,(. :~~~\ ........ 0--::::: :~ :f\'/:::~ -~ ,, v v \-- ... ' ' : .. ' --2 -2,- ,'\ 1881 1882 1883 1884 1885 -

    1 :. ' "'\, __

    -~ ~, .... ' \ \ \ \ . \ ..

    -

    -

    -2

    ;1-.-. :-.. -.~__,.,18.,..66,_...._-.-..... -...... f-, -.-... -. ,-, 1"""'8=87,..--/-.. -.. -+-..... -: ... -... :- //-.~=~88=_-_-'--, -,,, .-+ '.-..... - .. - ... -. ~ _...,1"""88"'"'9:.------+---/'---.~1~89:-:::0-----i_ , ..

    ~ '~-/ '/ '\:/< ... ' -1 -

    -

    -2 ~--~~~---r----~~----+-----~~--~----~~-----+-----~~--~ 2r- 1891 1892 1893 1694 1895

    -

    -

    11- /\ ., \ _ ........ ~'- ... , , ..... . -~ A. .. / ~ ... , ,/ .... .. 0 ..... '\::::: v 'V' ~' /- .......

    .,. ' I

    " '- I -

    -4r- ::~" . '1 __ _, : ..... ~r -

    -21-~--~~-----r----~~----+-----~~--~----~~----4-----~~--~ 2r- 1901 1902 1903 1904 1905

    -

    -

    1':

  • - 19- NW-Area Hydrography

    'C J f M A M J J A S 0 N D J F M AM J J A S 0 N D J F M A M J J A S 0 N D J f M A M J J A 5 0 N 0 J F M A M J J A S 0 N D

    21 '1911 ~ ~ ... ~ /

  • - 20 -

    Table 1. Monthly Anomalies (6. 0 C) and Numbers (n) of Observations of the Surface Temperature in the Area C (see Fig. 1) during the Years 1886-1939.

    March April May June July August September October J\ovember December 6. n 6. n 6. n 6. n 6. n 6. n 6. n 6. n 6. n 6. n

    I886 -I2 00 9 -08 2 -02 IO I887 05 -08 8 -08 I2 I888 05 01 4 07 4 1889 -01 lO 06 10 I890 04 4 10 I -06 5

    1891 05 4 09 IO 1892 08 15 3 12 1893 12 2 l-7 3 I894 04 7 I4 6 10 4 OI I -08 8 04 9 I895 I2 4 02 lO I7 5 -09 I5

    1896 -04 I 02 12 -06 1897 07 I 07 00 4 -03 I 1898 02 7 00 9 -09 9 1899 -02 2 00 6 01 6 -04 3 -01 17 10 5 00 5 1900 10 2 09 10 05 15 03 23 -0-4 11 00 I 00 I 1901 -OI 10 -10 9 03 10 03 ll -0.8 4 1902 -05 3 03 1 H 7 09 21 1903 03 3 -01 20 06 lO 07 l7 -08 4 1904 -07 3 00 5 16 12 06 9 1905 -0-4 2 -07 5 -H ll -I5 7 06 21 -03 15 I906 05 6 -22 2 -H 3 -02 11 -04 17 -05 25 04 IO I907 -02 6 -02 12 01 8 -03 7 -I3 41 -01 3 1908 00 16 -08 3 -10 2I 08 7 -03 28 -07 25 07 I3 1909 -02 8 03 9 05 12 06 18 03 15 05 31 05 7 1910 -07 7 -07 I -07 16 -04 5 03 22 -09 24 -03 2I 1911 -03 9 -08 9 -1.9 6 OI 7 04 8 -07 ll OI I8 1912 15 7 -05 ll 09 l7 06 9 I3 24 03 43 09 16 1913 -06 12 -01 16 -10 8 -06 16 01 32 -06 23 -03 8I 05 20 I914 00 7 -08 10 -05 32 -I6 22 -1.5 22 -09 24 -09 34 -07 30 00 2 1915 0.7 1 -02 6 -04 2 02 26 15 22 22 I 01 43 06 20 1916 02 14 -01 16 -IO 7 -02 6 03 40 -05 I7 10 3 1917 -04 1 04 28 09 7 18 25 13 24 -05 44 -07 37 -01 2 1918 -I7 7 -07 5 OI 4 -02 25 -H 55 -07 28 -12 76 -13 28 1919 --03 14 06 6 01 38 00 18 -08 14 -08 32 -06 26 04 3 1920 -12 -04 6 -02 12 03 l7 -01 11 -08 44 -13 43 00 26 03 3 1921 -15 16 -0.4 4 -03 21 03 10 -20 43 -l-6 l7 1922 -08 25 -1-4 2 -05 I4 -05 28 -1-4 75 -06 13 I2 3 1923 -1.0 3 00 1 08 12 -01 13 02 34 -03 23 06 17 04 2 1924 -01 10 -04 3 07 18 06 16 02 57 00 25 05 I8 -0.2 3 1925 -05 15 -08 40 -03 36 -02 48 -03 I5 -03 10 H 1 1926 04 3 04 24 02 IO 08 30 06 65 04 26 02 24 H 2 1927 03 5 07 I2 08 7 15 3 02 10 1-4 7 1928 -02 7 18 13 23 12 15 14 17 36 07 17 IO 23 24 4 1929 07 lO 09 8 13 19 16 I2 23 81 07 20 06 20 1930 04 20 1-4 19 07 40 10 4 01 31 13 23 08 9 10 5 1931 10 9 06 4 10 2 09 23 00 19 15 4I 12 I7 06 8 1932 I4 4 03 15 -02 lO 21 35 06 47 l-6 28 OI 58 07 28 13 6 1933 1-4 5 10 22 10 13 09 29 08 19 H 37 03 42 08 24 1934 08 9 06 17 -04 11 03 31 16 23 01 33 13 36 06 19 12 6 1935 09 3 OI 21 15 9 05 14 02 28 12 44 20 13 12 6 09 2 I936 1.6 2 13 20 06 24 06 17 19 17 17 3I 06 47 21 22 20 1 1937 09 4 00 23 00 18 00 18 10 32 05 37 00 25 05 25 10 2 1938 -04 37 00 21 13 15 02 24 -02 30 -H 61 -01 4 1939 1.5 07 15 04 12 01 IS 12 13 20 50 I7 49 13 7 12 2

  • Tables 2a & 3a. Monthly Anomalies (b. 0 C) and Numbers (n) of Observations of the Surface Temperature in the Areas D and E (see Fig. 1) during the Years 1876-1895. (1896-1939 on pp. 22 & 2.3),

    Area D January February March April May June July August September October November December 6. n 6. n 6. n 6. n 6. n 6. ll 6. n 6. n 6. n 6. 11 6. n 6. n

    1876 - - --- - -02 5 -01 20 02 27 -01 62 -12 10 -12 12 04 60 -01 lO 1877 - - - 03 19 01 48 H 41 -03 26 -02 49 04 25 13 42 07 27 1878 - - - - -- - 05 64 -02 66 04 50 H 24 03 37 02 55 05 29 1879 - - - 06 67 06 46 09 52 06 43 08 47 09 29 01 5 1880 - - - - - 04 60 0-4 56 01 58 22 43 l-0 50 03 22 H 16

    1881 - - - - 20 36 06 7l -01 51 02 28 -05 59 01 60 0-4 17 1882 - - - - 04 62 01 41 01 53 05 25 -04 64 -06 35 -0-4 21 1883 - 02 34 -03 48 -03 55 04 9 00 50 -02 51 -05 17 -13 6 1884 -06 4 - - - -03 32 -07 38 -13 64 -13 30 -l-7 66 -20 30 -l-8 30 02 1 1885 -0.6 6 - - -05 37 -06 56 -06 33 -12 29 -01 14 -0-4 49 -06 27 02 5 -09 l

    1886 - - - - - - -08 48 02 30 -02 56 01 42 07 12 -02 72 01 40 - 04 2 1887 - - - - - 02 32 05 38 00 65 00 19 -03 53 05 29 12 36 - - 20 4 1888 - - - - 03 13 06 56 09 82 12 42 H 49 06 16 20 25 15 4 1889 - - - - l-0 13 0-4 20 03 69 -05 21 -01 43 04 33 06 8 1890 - - - - -03 27 03 40 07 50 -0-4 33 -06 74 -08 26 -01 15 02 2

    1891 - -. - - 02 25 04 42 08 55 06 lO 03 68 04 36 -07 14 -04 l 1892 - - - 06 33 07 33 13 49 08 20 1-4 32 -02 54 07 43 06 19 02 4 1893 24 1 - - - 07 56 08 34 1-4 53 H 54 1-4 50 l-8 81 07 8 15 3 03 3 1894 - - - -05 12 00 46 08 48 -01 61 -04 42 -07 26 03 44 08 51 07 6 - - 1:.,:) 1895 02 1 - - 06 1 12 33 09 35 07 79 07 29 02 51 07 65 02 22 02 4 09

    Area E.

    1876 - - - - - - - - - - - - - - - - 00 1 1877 - - - - - - - -03 7 01 4 05 2 -04 5 1878 - - - - - - - - - 09 5 08 8 - - - -- 07 7 1879 - - - - - - - - - 02 6 - - - 00 9 1880 - - - - - - -02 14 - - 07 5 12 17 H 15 05 9 H 14 07 l

    1881 - - - - - - - - -01 17 -03 8 -10 32 -06 13 00 5 1882 - - - - -15 16 02 6 --12 13 -10 13 -07 28 -02 ll 00 5 -1-0 5 00 5 1883 - - 08 9 -06 13 -01 19 -07 8 06 20 03 24 08 ll -02 ll -2-1 lO -04 22 1884 -26 8 -08 ll -H 15 -H 18 -08 18 -07 30 -l-4 32 -15 44 -12 36 -12 45 -10 45 -13 22 1885 -09 56 -12 23 -07 26 -04 27 -15 20 --15 27 -01 44 02 49 -03 45 07 45 12 36 02 20

    1886 - 1-4 8 02 13 12 24 05 39 1-4 28 12 43 01 41 02 48 00 63 03 45 H 47 1887 -06 32 05 26 15 23 19 14 17 20 12 23 03 40 08 49 08 51 17 51 09 44 1-9 55 1888 l-6 18 26 26 23 14 l-6 28 25 25 19 36 09 28 1-3 27 09 19 23 22 02 28 0-4 24 1889 19 17 1-4 28 19 16 l-0 8 08 12 -03 12 10 28 05 26 15 26 03 ll 1890 -01 25 l-0 9 -01 12 -04 6 -15 7 02 ll 09 2 1-4 14 03 24 H 30 -06 23 -02 33 ::r::

    10 19 -08 49 00 44 '< z

    1891 H ll 06 12 09 11 1-4 24 06 18 06 38 1-4 45 00 46 07 21 1f :E 1892 - - 05 26 05 17 10 19 05 22 00 47 07 46 06 56 08 50 14 82 H 56 J.6 35 ~ I 1893 13 37 12 6 09 22 l-4 24 05 18 05 31 06 58 05 47 12 58 06 7l l-8 44 08 66 ~ > 1894 H 43 02 22 01 20 -05 28 08 34 -03 30 -09 31 -08 38 -01 55 01 39 -08 47 -01 49 "' 1"'1 1895 0-4 42 06 28 02 21 00 31 -02 27 02 29 05 27 -01 68 -03 67 -0-4 61 01 80 Q"'('!) -01 69 '< ~

  • Table 2. Monthly Anomalies (L.l 0 C) and Numbers (n) of Observations of the Surface Temperature in the Area D (see Fig. 1) during the Years 1896-1939.

    January":.; February March April May June July August September October November December Ll n Ll 11 Ll n Ll 11 Ll 11 Ll 11 Ll 11 Ll 11 Ll 11 Ll 11 Ll 11 Ll 11

    1896 04 1 - - - - 08 37 02 26 02 78 -06 34 05 36 07 34 -02 25 05 7 -05 1 1897 17 l - - 02 12 02 22 -02 53 00 26 -01 83 -04 43 -02 46 -02 24 09 4 18 5 1898 - - - - - - 02 59 -0-4 13 07 78 06 23 -01 78 -05 70 -02 49 -H 6 05 1 1899 - - - 01 7 -01 55 06 52 00 40 -04 69 03 49 03 43 -02 45 -09 8 06 7 1900 - - - - 08 4 -03 24 0-4 47 03 91 07 23 00 94 01 33 -02 26 -05 29 00 13 1901 -08 1 - - 02 12 00 66 02 63 -02 83 13 29 -06 82 -06 45 -09 44 06 10 -05 1 1902 - - - - - 01 56 05 42 08 81 09 33 13 66 l-6 39 06 26 02 18 -(H 5 1903 09 1 06 I - - -01 49 -06 37 -01 74 -01 63 04 52 00 89 06 23 00 25 -1-l ').7 1904 02 6 -2-4 1 - - -06 66 -07 34 -06 7l 03 34 -01 40 -07 75 -1-4 23 -06 19 -Hi 8 1905 -03 4 -04 1 - -08 18 -09 35 -0-4 57 -06 27 -05 4.8 -10 32 -01 ll 03 4 -15 1

    1906 - - - - 00 13 -13 34 -06 84 -07 41 -06 82 -07 37 -H 44 -08 34 03 4 18 l 1907 04 2 - - - - -H 66 -08 31 -08 58 -D-7 51 -H 42 -06 40 -02 50 -21 1 1908 -06 1 - - - -03 44 -09 51 -12 54 -03 72 -10 52 -09 41 01 51 -01 5 1909 - - - -04 l7 -04 50 -02 28 04 42 00 58 -02 42 -01 31 -01 56 l-6 l 13 1 1910 - - - - - - -0-4 7l -o-7 87 01 47 -07 63 02 49 -04 43 -05 66 00 22 04 1 1911 1-l 2 - - 02 10 -07 55 -07 60 -05 25 -04 92 06 75 01 33 05 36 -06 5 1912 - 09 1 -01 12 00 72 -03 49 05 33 . -01 112 07 60 03 72 -09 55 01 32 1913 -0.5 1 - - -08 2 -08 163 -10 121 -10 69 -05 42 -08 90 -1-4 47 -05 72 -03 43 1914 - - - - -05 21 -09 104 -1-l 48 -1-4 55 -l-6 76 -15 79 -10 51 -09 57 -06 4 -OS 2 1915 - - 07 1 00 7 -06 133 -03 52 01 7l 13 78 13 54 08 85 07 45 03 33 0-4 1 t-:l t-:l 1916 06 2 - -04 8 -02 196 01 59 -08 31 00 29 -05 77 07 59 05 43 00 14 1917 01 2 - - -18 2 09 31 05 56 04 87 1-4 47 1-4 23 H 43 -1-4 l7 0.1 6 15 1 1918 - - - 00 16 09 28 03 55 -06 84 -l-3 44 -05 7l -1-4 80 -13 40 -06 27 1919 -02 2 H 1 - 00 19 05 50 -01 12 -05 20 -07 108 -06 22 -06 59 10 32 1920 - - - -09 9 -05 15 -02 7 02 6 -05 131 -08 58 -13 51 00 20 -10 41

    1921 04 I - - - -04 64 -06 19 -12 68 -10 38 -10 103 -1-l 51 -04 37 -09 45 1922 1.7 3 - - - -02 80 -08 56 -12 81 -1-6 65 -04 l7 -l-7 83 -07 29 -08 18 1923 - - - - -01 13 -04 95 01 26 -01 40 02 81 -02 '10 -09 59 -03 57 04 17 -04 2 1924 2-4 3 - - - 00 30 02 64 07 36 12 91 07 39 -01 59 00 38 -02 41 -07 4 1925 19 4 -19 1 -21 1 -08 235 -05 84 -05 70 -08 104 -12 55 -13 59 -04 58 0-4 36 12 2

    1926 2-4 3 H 1 -05 10 02 76 06 131 01 53 02 44 -06 72 -08 82 -08 55 00 79 05 14 1927 12 3 -03 2 -13 ll 06 12 0-4 9 0-4 64 07 53 12 35 06 36 02 53 06 19 09 16 1928 08 4 -15 3 -02 33 01 60 12 62 19 51 15 34 10 65 02 64 1-l 63 03 40 05 8 1929 19 5 - - 06 8 09 72 -03 25 03 33 08 50 1-l 64 02 55 01 55 -05 42 -10 ~0 1930 02 8 - - -05 1 03 105 05 51 00 54 -05 106 02 81 10 93 00 84 03 29 1931 20 8 -02 3 -06 29 -01 107 06 42 1-l 51 03 59 06 27 1-4 58 03 33 -1-l 14 l-6 4 1932 - - - - 10 16 05 59 12 25 I-6 26 l-1 30 l-1 23 05 55 02 25 01 23 1933 07 5 - 07 25 07 53 12 .31 06 20 07 31 01 20 00 31 0-4 38 03 41 ] 3 3 1934 07 2 - -04 12 01 65 -02 26 00 43 03 12 02 35 00 57 -01 27 06 27 08 2 1935 28 2 -0-4 1 02 15 05 29 08 ;24 05 20 -08 6 --02 18 07 13 -02 47 -12 11 -02 1

    1936 - - 06 1 09 16 09 50 07 56 05 29 13 26 07 7 09 27 15 32 01 26 1937 1-8 9 - - 12 7 01 80 01 42 02 60 -04 42 -05 24 -0-4 36 -02 39 01 47 17 7 1938 29 4 - - 02 4 03 59 01 48 -01 31 -05 38 -09 26 -07 21 -10 22 -06 52 08 3 1939 - - - - 02 ll 01 62 04 51 -03 10 1-l l7 06 15 04 26 07 31 10 1

  • Table 3~ Monthly Anomalies (6.. C) and Numbers (n) of Observations of Surface Temperature in the Area E (see Fig. 1) during the Years 1896-1939.

    January February March April l\Iay June July August September October November December

    6.. n 6.. n 6.. n 6.. n 6.. n 6.. n 6.. n 6.. n 6.. n 6.. n 6.. n 6.. n

    1896 06 61 08 43 05 47 08 23 05 22 -02 32 -02 82 08 61 09 67 07 83 13 68 07 59 1897 H 63 10 35 -03 31 -01 24 -02 31 04 29 02 46 -02 55 -02 75 02 88 08 41 -03 72 1898 05 24 05 17 05 27 -01 33 06 39 09 51 1-8 77 12 108 12 116 -04 87 --05 49 -05 56 1899 -01 28 -04 17 05 33 04 25 1:? 33 03 34 01 75 09 74 05 60 09 so 05 105 13 69 1900 03 5 H 17 22 32 12 42 07 44 -02 40 --10 48 -12 83 -02 109 -02 101 -02 104 01 86

    1901 00 52 06 38 03 54 01 48 -03 62 01 60 -07 64 -01 68 -04 98 -15 75 02 70 08 80 1902 06 73 15 27 H 26 06 55 1-S 44 08 64 1-4 56 1-6 54 13 84 02 72 -02 64 -07 75 1903 00 54 -01 56 --13 54 -05 26 -12 40 -06 66 -06 96 -08 85 -02 77 -0-4 106 -01 129 01 86 1904 -09 90 -10 64 -12 75 -10 34 -09 48 -1-4 58 -15 61 --10 88 -17 101 -17 143 -07 no -06 86 1905 -08 70 -07 44 -H 38 -04 41 00 42 -15 56 -15 49 -10 89 -08 63 02 76 -03 46 -03 31

    1906 -01 42 -04- 30 -01 27 02 39 00 69 06 56 -01 52 -l-1 124 -10 105 -09 118 -05 80 00 45 1907 00 15 -06 40 00 30 02 38 -05 65 -07 55 02 99 -05 100 -01 83 -01 105 -05 57 -07 37 1908 -01 12 03 46 -04 36 -04 39 10 43 -10 51 -06 45 02 64 00 74 -05 66 01 68 -0-4 37 1909 -05 10 02 31 10 38 00 42 05 37 08 69 07 23 08 69 08 56 02 79 1-8 40 1-4 44 1910 09 9 06 20 -07 37 08 30 05 28 04 55 04 24- 01 4-5 06 58 01 64- 07 76 09 36

    1911 06 30 00 36 -02 49 02 39 -07 49 02 41 07 36 05 92 01 84- 06 84 -07 84- -07 30 1912 -03 20 -04 50 -07 33 02 28 -02 8 -06 10 -1-8 31 -H 22 -08 58 -13 64 -03 63 -14- 32

    1913 -19 37 -12 42 -23 4-1 --1-7 4-5 -Hi 27 --1-8 30 --02 39 -09 4-8 01 69 -10 94- -20 64 -08 31 1914- 02 25 -21 33 -1-8 10 -13 29 -1-0 38 03 31 -09 63 -1-3 67 -07 70 -08 14-6 -1-7 47 -1-4- 26 1915 03 35 -09 27 09 69 07 36 H 28 H 48 09 4-8 01 4-3 01 68 -02 66 07 51 00 34- tv w 1916 06 17 --H 28 01 4-0 -04- 34 -06 39 02 91 13 44- 04- 139 07 80 06 95 --09 75 01 17

    1917 --03 4-7 0-4 13 -1-4 5 21 15 H 30 06 47 06 44 13 18 06 8 03 12 -28 3 1918 - - - -06 4 -04- 11 -05 6 -02 10 -15 9 -07 7 -04 16 -08 26 -06 24- -07 17 1919 -07 64 -01 23 -09 4-7 02 37 00 23 -07 23 - - l-1 27 -02 28 03 36 09 4-7 -08 26

    1920 -04- 37 -09 38 -H 24 -20 9 02 3 -10 11 -15 24 -05 31 -10 4-0 ----02 40 -13 49 -10 40

    1921 -04 9 -09 18 -12 21 -1"2 36 -09 21 04- 21t 07 26 -06 20 -1-l 38 -03 28 -01 53 05 22

    1922 -08 32 -05 18 -09 23 -21 8 -08 21 -12 16 -19 18 -21 24- -06 34- -07 32 12 26 13 ll

    1923 04 14- --10 20 -07 20 -15 17 07 20 09 19 -25 33 -13 28 -07 39 -02 54 08 47 1-4 26

    1924- -01 20 06 25 08 21 12 18 07 19 05 23 08 19 -03 18 0-4- 61 03 45 02 45 -01 30

    1925 -1-6 10 --06 28 03 26 02 31 -03 35 03 24 06 17 -07 35 07 38 04 63 0-4 39 07 20

    1926 07 16 -03 22 -08 18 --05 22 02 40 -08 14 -03 27 -10 34 -05 56 -02 47 -03 49 10 59

    1927 08 20 07 19 00 18 -04 15 H 21 07 35 08 33 03 69 02 79 -05 56 04 68 08 31

    1928 07 21 -09 24- -06 43 -08 30 09 23 06 37 0-4 49 01 65 -03 53 -03 tiO -03 50 -06 33

    1929 -03 42 --04 29 01 39 01 39 -04 20 -07 37 02 48 05 73 00 87 -03 110 -05 43 -1-0 66

    1930 -09 40 -15 56 -01 35 -02 36 -06 49 -08 83 07 72 02 81 0-4- 107 -04 108 03 67 -07 61

    1931 13 26 -03 6 10 4 -02 21 04 34 05 42 03 35 01 37 18 58 05 37 -05 19 05 20

    1932 - - 12 10 -06 13 --02 7 06 14 09 26 08 29 H 25 22 39 25 29 13 30 00 10

    1933 -02 22 H 7 -05 14 0-4 28 04 33 01 29 -03 17 02 19 06 40 09 40 00 33 05 16

    1934 -0-4- 8 12 14 -H 15 04 14 00 21 03 20 07 20 -01 27 03 37 01 31 10 22 05 10

    1935 02 8 -09 8 -09 7 01 9 0-4- 7 -15 9 -10 9 -01 19 -06 31 00 10 -03 12 15 9 ~z 1936 - - 06 4 07 14 06 13 01 24 -03 6 02 44 1-4 15 09 16 -01 22 03 21 - - 8~ 1937 -07 24 01 24 -02 19 02 ll -06 30 22 39 23 9 12 38 13 31 -02 31 12 35 1-8 23 1938 H 16 - - -01 () 06 8 03 26 13 30 07 15 - - - - - - - - -09 20 ~> 1939 - - -10 16 -H 11 - - - - - - - - - - - - - - - - -

    II> >"I - 'C (!)

    ~~

  • -21-

    Table 4. Monthly Anomalies (~ o C.) and Numbers (n) of Observations of the Surface Temperature in the Areas A, B, C, D and E (see Fig. 1)

    for the Period July 19!5-December 1946. Area A B c D E

    Month ~ n ~ 11 ~ n ~ n ~ n

    July 1945 00 34 -05 59 08 24 01 18 August

    " 08 40 -13 35 09 37

    September -06 72 01 21 01 1l 00 5 October 04 64. -05 44 01 21 -11 3 November 13 1 17 l 11 12 December -05 1 06 1

    January 1946 February March

    " April 02 7 07 59 02 33 06 43 May

    " l-1 48 05 78 12 40 00 29

    June 07 38 04 40 20 41 07 ll July 00 87 -07 86 -01 30 -02 14 August 00 18 -05 30 01 13 -07 21 -14 8 September

    " 04 73 -06 120 -02 70 -10 36 -03 16

    October "

    14 15 04 43 1-l 46 08 18 12 17 November

    " 02 18 00 36 12 5 14 14 -12 15

    December "

    -04 6 l-1 3 25 4, 09 25

    TH~E FISH.

    Lemon Sole. Faroes.

    During 1946 eight samples of lemon sole measurements and scales were obtained from Aber-deen trawlers fishing at Faroe. These, totalling 765 fish, exhibit the following size frequencies in 5-cm. groups.

    < 25 26-30

    0 /o 20

    26 168

    220

    31-35 36-40 41-45 46-50

    314 212 48 3 410 277 63 04

    Compared with similar figures for the previous year this shows a general reduction in the size of lemon soles now being caught at Faroe. Too much emphasis, however, should not be placed on this point since the 1946 samples include a number from north coast grounds between Myling Head and

    Locality Broods 1943 1942 1941 1940 1939 1938

    Year 3+ 4+ 5+ 6+ 7+ 8+

    Fugl, Bord No. 1 2 40 ll 57 20 Grounds Ofo 04 08 168 46 239 8-4 N.W. Mygge- No. 30 .::.o ll8 21 108 29 mes to N.E. o/o 57 38 224 40 205 55 Fugl

    Fugl which normally support a larger percentage of younger, and therefore smaller, fish than other Faroese grounds. On the other hand, the average size of 501 lemon soles from Fugl grounds in 1945 was 352 em., whereas the average for 238 fish from approximately the same grounds in 1946 is 341 em.

    The age composition of the 1946 samples is as given in the table below.

    Both sets of figures agree in confirming last year's results by emphasising the predominance of the 1937 and 1939 broods and also to a less extent that of 1936. Towards the end of 1946 the 194? brood began to appear in the catches in greater numbers with the result that from grounds lying off the north coast of the islands it exceeds all others numerically and already gives promise of being above average strength.

    1937 1936 1935 1934 19.33 1932 1931 1927 Total 9+ 10+ 11+ 12+ 13 +- 14+ 15+ 19+-

    43 29 14 13 3 2 2 1 238 181 122 59 55 13 08 08 0-4 1000

    103 53 28 11 4 1 526 196 101 53 21 08 02 1000

    Bennet B. Rae.

  • - 2.5 NW-Area Iceland . Herring

    Herring. Larval Herring. Iceland 1946 (10 minutes' hauls). Stat. No. 6451 6452 6453 6454 6455 6456 6457 6458 6460 6461 6462 6463 6464 Date 10/9 11!9 11/9 11!9 11/9 11/9 11!9 12;9 15/9 15/Y 16;9 16/9 16/9 I lour. 23 25' 5 00' 7 40' 11 05' 13 5.5' 19 31' 22 17' 4 30' 15 00' 21 00 0 20' 3 35' 7 35' N.Lat. 6425'5 6447' 6447' 65 11' 6526' 6600' 6616' 65

  • - 26-

    Iceland.

    / / I \ ) I

    26 20 18 16

    /? \

    I

    12

    J //'---, .--' i

    J /

    c::.::.:-;... v ... , (

    ('-.J /

    ./

    Herring. Larval stages. September 1946. e larvae present. Total catch per Y:: hour hauls and average size in mm. of larvae indicated.

    X larvae not present.

    Occurrence of Larval Stages. Autumn 1946. During the "Dana" cruise to Iceland in Septem-

    ber 1946, a survey of the pelagic stages of herrino-larvae off the west- and south-west coasts wa~ carried out. Unfortunately investio-ations could not be carried out along the north a~d the south-east ?oasts o~ing to lack of time etc.; consequently ~nform!l-tiOn from these parts of the Icelandic area IS lackmg. The material was collected with the 2-m. stramin net by 30-minute oblique hauls. The richest hauls were obtained off north-west Iceland where the maximum catch per haul was abou~ 1,500 specimens; the average size here being about 16 to

    18 mm. The prevailing currents in the area had obviously carried the larvae from the spawnino-places at the mouth of Faxa Bay to more norther!~ localities; and probably also to the north coast, from whiCh area no observations are available as already stated. The average size of larvae 'was greatest at the .southern stations, where spawning commences earher than further north. This year-class seems to b~ above the. average for the pre-war years for which observatiOns are available ( ef. Rapp. ~t Proc. Verb., Vol. XCIX, 1936, VI and Ann. Bwl. I, 1943, p. 86). Details are given in the accompanying table and on the above map.

    Taning.

  • - 27-

    Plateau Continental Atlantique.

    INTRODUCTION.

    L'activite reste toujours reduite dans le secteur du Plateau Continental Atlantique et, seules, sont parvenues aux Annales Biologiques, quelques con tributions de l'Eire et de la France.

    Elles resument, sous forme de tableaux, les observations biometriques faites sur les lieux de peche ou au debarquement sur les especes come stibles suivantes:

    Merlu (Merlucius merluccius Linne) Plie ( P leuronectes platessa Linne) Cardine (Lepidorhombus megastoma Donovan) Hareng (Clupea harengus Linne) Sardine (Sardinia pilchardus Walbaum) Anchois (Engraulis encrasicholus Cuvier) Argentine (Argentina sphyraena Linne) Maquereau (Scomber scombrus Linne) Grondin gris (Trigla gurnardus Linne)

    ]. le Gall.

  • - 28-

    THE FISH. Merlu.

    Mensurations. Les mensurations effectuees en 1946 par les

    Iaboratoires de Concarneau et de La Rochelle portent sur plus de 10,500 individus. Toutes furent effectuees a terre sauf celles du mois de Fevrier (Petite et Grande Sole) qui le furent en grande partie a Ia mer. Ces dernieres peuvent par suite etre considerees comme assez representatives de l'etat du stock pour ce mois et ce secteur. Elles montrent qu'entre 47 et 72 em. toutes les classes etaient egalement bien representees.

    Au cours du premier trimestre plusieurs classes apparaissent nettement autour de 17, 27 et 37-39 em. Une autre classe est egalement bien indi-

    quee entre 53 et 55 em. en Janvier-Fevrier puis entre 55 et 57 em. en Mars. En A vril-Mai les jeunes de 17 em. se retrouvent autour de 20 em.

    Au dela de 60 em. les diverses classes paraissent avoir des valeurs numeriques tres voisines et les sommets qui les representent sur le graphique sont vraisemblablement compliques par Ie fait que les differences de taille entre cJ et 9 s'amplifient a partir de 60 em. (cf. Hick I in g: Rapp. Atlant. 1930, Rapp. et Proc.-Verb. Vol. No. 77, p. 57).

    En Septembre Ies mensurations ne sont pas assez nombreuses et Ia courbe de population ne montre aucun sommet bien net si ce n'est a 37, 49 et 60 em.

    Tableau 1. Mensurations Effectuees en 1946.

    II III IV V Janvier Fevrier Mars Mars Mars

    VI Avril

    VII Mai

    VIII Mois

    Origin e. N. du Golfe pteetGde Sole N. du Golfe pte etGdeSo!e N. du Golfe N. du Golfe N. du Golfe

    Septembre Melville-Jones Bk. Letacon-Observateur. Letacon- Letacon-noux noux

    Nbre d'individus 878 2,167

    Tailles de 5 en 5 em.

    10-14 15-19 20-24-25-29 55 30-34 363 41 35-39 1116 326 40-44 1218 599 45-49 1127 1226 50-54 2881 1674 55-59 2391 1292 60-64 704 1224 65-69 112 1338 70-74 1025 75-79 11 558 80-84 11 308 85-89 11 216

    . 90-94 86 95-99 63

    100-104 12 105-109 08 110-ll4 04

    10000 10000

    Forest

    2,017

    Forest

    1,290

    Dizerbo

    659

    Dizerbo

    1,538

    Dizerbo

    1,474

    Frequence des tailles pour mille individus.

    273 1026 249 817 505 109 465

    1555 1048 1178 996 782 486 343 118 49 01

    47 380

    1301 2054 1386 800 620 845 888 697 309 270 225 139 31

    08

    10000 10000

    Taille moyenne:

    770 30 7025 4020 3325 1995 5520 6530 210 400 130

    30 15

    10000 10000 10000

    178 200 204 em.

    noux 548

    18 18

    366 784 604

    1077 1496 1769 1624 694 329 347 293 218 181 110 54

    18

    10000

  • - 29 Atl. Slope Hake

    Correlation Taille/Poids. La variation du poids par rapport a la taille L'etude du rapport entre la taille et le poids du

    peut etre representee par les formules suivantes (Forest):

    merlu repose sur l'examen de 845 individus vides. Merlus de moins de 32 em.: P = 00037 X3H. Les chiffres obtenus a Concarneau et La Rochelle

    ne concordent pas exactement, ceux de La Rochelle Merlus de plus de 32 em.: P = 0005 xso2. etant, pour les merlus entre 30 et 50 em., plus P etant le poids et X la taille. forts de 10 a 20 g. en moyenne. Cette difference Le poids du merlu est done, les jeunes individus provient des methodes de pesee utilisees: une pesee etant mis a part, sensiblement proportionnel a la par individu a La Rochelle, une pesee pour plu- puissance cubique de la taille. sieurs individus de meme taille a Concarneau. R. Letaconnoux.

    Tableau 2. Relation Taille/Poids. (Merlu vide.) Concarneau. La Rochelle.

    Etendue N.ll Concarneau. I La Rochelle.

    em. N. Poids Poids Limites de em. N. Poids I Poids Limites de Etendue N. moyen moyen Ia variation moyen moyen la variation 23 19 71 64 1,600 1,4,00-1,800 400 2 24 37 83 70 1 65 l 1,410 1,550 1,500-1,600 100 .1, 25 33 93

    66 l 1,570 1,953 1,820-2,020 200 3 26 41 105 67 l 1,470 1,733 1,600-2,000 400 3 27 39 118 68 1,832 1,600-2,200 600 5 28 39 135 69 1,700 1,400-2,170 770 6 29 46 146 167 160- 175 15 2 70 1,940 1,800-2,000 200 5 30 35 162 172 170- 175 5 2 71 2,220 2,100-2,380 280 4

    72 2,289 1,900-2,510 610 "' 31 27 178 200 185- 215 30 4 I 32 24. 197 216 200- 230 30 10 73 l 2,060 2,267 2,110-2,560 450 4 33 17 214 230 200- 260 60 21 74 2,363 2,000-2,560 560 6 34 8 235 249 215- 280 65 30 75 1 2,300 2,536 2,100-2,860 760 u 35 18 256 265 215- 310 95 32 76 l 2,560 2,511 2,300-2,800 500 9 36 9 282 287 260- 335 75 30 77 2,707 2,500-3,065 565 8 37 5 300 307 270- 345 75 22 78 2 2,460 2,771 2,500-3,115 615 4 38 4 315 336 285- 390 105 19 79 2,875 2,500-3,100 600 7 39 3 337 376 350- 390 40 8 80 2,683 2,600-2,835 235 4 40 3 373 378 330- 415 85 8 81 2,885 2,400-3,000 600 7 4.1 3 417 433 375- 510 135 8 82 3,200 l 83 3,040 2,700-3,300 600 9 4.2 454 425- 495 70 4 84. l 3,850 3,400 l 4.3 511 495- 530 35 4 4.4 5 520 538 500- 560 60 .-, 85 3,400 l J 45 2 550 570 510- 615 105 7 86 3,942 3,925-3,960 35 2 46 l 530 602 570- 640 70 5 87 3,525 3,300-3,700 400 4 47 8 620 614 580- 640 60 6 88 48 6 655 620 600- 660 60 4 89 4,000 3,700-4,300 600 6 49 5 670 701 640- 740 100 6 90 3,700 3,300--4

  • - 30

    Plie.

    Observations sur les Stades jeunes de Ia Plie.

    Des le debut de l'ete, la Baie de l'Aiguillon au Nord de La Rochelle est peuplee d'un grand nombre de jeunes plies. Le 18 Juin, en 37 minutes de dragage avec un chalut a crevettes sur des fonds de 4 a 5 metres, nous avons pu recueillir 123 individus dont 105 appartenaient au groupe 0 et dont la taille allait de 40 a 80 mm. (moyenne 57 mm.). Les 18 autres appartenaient au groupe I et mesuraient de US a 189 mm. (moyenne 162 mm.) 1)

    Le 29 Juillet, dans la Baie de Morlaix (plage de Penpoull), no us avons pu mesurer un autre lot de jeunes plies appartenant toutes au groupe 0 et qui faisaient de 45 a 100 mm (moyenne 73 mm). Cette seconde capture f ut f aite a la senne sur la greve; nous n'avons trouve aucun individu du groupe I.

    1) Age determine d'apres l'examen des otolithes.

    % JO

    25

    20

    15

    10

    6r. 0

    A

    ' '.._ ......

    -

    Gr. 0. mm. n Dfo ll o_,o

    40 1 09 45 13 125 2 2.2 50 19 181 3 33 55 23 219 4 45 60 21 200 3 33 65 15 143 19 21-l 70 7 66 15 167 75 5 48 14 156 80 1 09 10 ll1 85 8 89 90 5 55 95 3 33

    100 4 45 ---------- ----

    105 100 90 100 (A) (B)

    A. Echantillons du 1 () .Tuin.

    Gr I

    40 50 60 70 80 90 100 110 120 130 140 I 0 160 170 180

    Fig. l. Representation graphique des tailles en mm. pour les groupes 0 et I le 18 .Tuin (A) et Ie 29 Juillet (Bl.

    Cr. I. mm. ll 0/o

    llO 1 55 120 130 1 55 140 1 55 150 5 278 160 4 22;) 170 3 167 180 3 167

    -----

    18 100 (A)

    B. du 29 Juillct.

    R. Letaconnoux.

  • - 31 - Atl. Slope Plaice, Megrim

    Cardin e. Cardine (Zeugopferus megastoma). I. Repartition par Tailles.

    Date: F evrier 1946 Mars 1946 Septembre 46 S. E. Irlande

    Septembre 46

    Origine: 46N.320'W.G. Grande Sole Small's-Melville Grande Sole Jones Bank

    Nombre: 239 102 123 862 Tailles en em. frequence Ofo frequence Ofo frequence Ofo frequence O,'o

    15 100 16 05 17 05 100 105 18 25 405 19 63 195 58 20 585 39 465 21 500 1175 21 22 585 1175 23 23 835 78 07 24 96 88 1-4 25 5-45 88 07 26 335 295 325 l-15 27 42 685 325 125 28 29 49 65 265 29 375 195 49 545 30 29 100 57 57 31 08 39 165 695 32 08 405 555 33 42 195 975 86 34 500 195 405 5-45 35 5-45 195 73 685 36 165 1055 59 37 25 100 815 615 38 165 295 65 35 39 25 100 325 300 40 165 100 2-45 165 41 25 295 57 165 42 05 325 08 4:3 25 100 2-45 045 44 05 08 45 08 2-45 0-45 46 100 07 47 100 08 095 48 100 035 49 245 07 50 195 035 51 025 52 03 53 100 08

    10000 10000 10000 10000 Modes 19-24-27 21-22-24 28-30-33 19-22-24

    29-35-37 25-27-31 36-41-45 31-33-35 39-41-43 38-41 49 37-44-47

    49 Moyenne 279 em. 27-45 em. 338 em. 3115 em. Observateur Let a con Let a con Let a con Dizerbo

    noux noux noux et Forese

  • - 32-

    II. Croissance. (Etablie suivant la repartition precedente et les resultats obtenus par Furn estin).

    Origine Taille modale a: 3 ans 4 ans 5 ans 6 ans 7 ans 8 ans Golfe de Gascogne em.: 19 24 27-29 35-37 39--41 (Fevrier 46)

    Grande Sole em.: 19 22-24 31-33 35-37 4.1-44 4.7-49 (Septembre 46)

    Observations: La representation de chaque sexuel portant sur la taille: a age ega!, les femelles classe d'age par deux modes, a partir de 4 ou 5 sont un peu plus grandes que les males (F u r n e-ans, s'explique par I' existence d'un dimorphisme s tin. Rev. Trav. Office des Peches Marit., VIII, 2.

    III. Correlation Tailles et Poids (en centimetres et en grammes) - Poisson vide

    Observateur: Observateur: Letaconnoux Taille

    Forest Poids Nom- Po ids Limites de Nom-

    moyen bre moyen variation bre

    17 33 9 18 40 35 19 47 50 20 54 40 21 63 18 22 73 20 23 80 6 24 95 9 25 105 ') ' 26 128 5 135 115-150 4 27 176 3 157 145-170 4 28 172 4 170 155-185 8 29 182 13 187 170-205 6 30 194 22 200 170-230 7 31 204 26 222 215-230 2 32 233 22 252 230-265 5 33 250 30 262 230-295 12

    0 b s e r vat ions: Les resultats du tableau de gauche proviennent de pesees effectuees par groupes de tailles, tandis que ceux du tableau de droite sont dus a des pesees individuelles des poissons.

    Si l'on represente sur un graphique a coordon-

    Observatcur: Observateur: Let a conn o u x Taille

    Forest Po ids Nom- Poids Limites de Nom-moyen bre moyen variation bre

    34 283 22 265 250-280 5 35 314 25 297 255-340 9

    36 322 24 341 280-390 13 37 350 30 372 345-385 10 38 382 ll 384 320--425 8 39 425 12 406 360--435 4 40 450 ll 453 445--460 3

    41 478 8 511 425-575 7 42 550 6 483 440-550 4 43 590 4 551 520-580 3 44 625 5 45 647 3 670 595-770 3

    46 665 3 47 760 8 815 1 48 780 3 49 941 905-1000 3

    nees logarithmiques les poids a chaque taille, on obtient une droite dont la pente a est de 31: Le poids s'accro!t done plus vite que le cube de la taille.

    Dizerbo, Fa rest et Letaconnoux.

  • - 33 - Atl. Slope Herring, Sardine

    Hareng.

    Sizes and Age-Groups of Irish Herring Samples 1946.

    Locality Date Length in ems. expressed as Percentage of Sample

    22 23 2+ 25 26 27 28 29 :30

    Howth 26/6/46 16 40 97 195 325 195 113 16

    " 26/7/46 11 47 170 228 356 148 37

    " 8/8/46 07 1-4 28 142 250 321 192 42

    " 5/9/46 07 35 78 285 300 250 42

    Kinsale 16/10/46 H 29 11 122 187 233 222

    " 19/11/46 13 13 165 268 227 213

    2 3 Age-Groups as Percentage of Sample

    4 5 6 7 8 9

    Howth 26/ 6/46 162 444 76

    " 26/7/46 116 339 169

    " 8/8/46 71 396 95

    " 5/9/46 270 480 80

    Kinsale 16/10/46 41 59 65

    " 19/ll/46 21 108 122

    Sardine.

    Sardine entre Loire et Gironde. Les observations. effectwes de Juin a Octobre

    194-6 montrent que dans la region du Golfe de Gascogne comprise entre Loire et Gironde, la peche de la sardine portait sur deux groupes dis tincts: G r o u p e I. D'importance numerique decroissante de Juin a Octobre, sa taille modale passe durant la meme periode de 120 a 150 mm. Sa moyenne vertebrale est de 5222 -+- 0163. G r o u p e 0. Apparu en automne, il remplace peu a peu les sardines du groupe I par des sardines presentant deux modes distincts a 105 et 115 mm. et dont la moyenne vertebrale est de 5202 -+- 0177.

    196 42 34 25 09 178 89 71 26 285 47 79 07 07 160 10

    239 227 186 95 29 280 143 129 108 79

    %

    lo

    lo

    to

    IOO \\0 lf.O 1:5(1 JlfO liO fM\.

    % lo

    lo

    10

    09 08 07

    23

    Juin

    31

    157 82

    11

    29 07

    G. P.

    Les sardines du groupe I, issues de pontes d'hiver, ont une taille a L1 inferieure a celle du groupe 0 issu de pontes de fin d' ete ( 95 mm. contre 115 mm.). La moyenne vertebrale de l'en semble de ces sardines est de 5214-+- 0081.

    % ..._...._-7.::~=--~~---1.-~...%.,70 Septemb~e

    lo

    R. Letaconnoux. octobre

    Novembre..

    Fig. 2.

    32

    23 13

    Farran.

    c .... 1 Gr. 0

    98,Z% !,&%

    O'% lOO%

    Modifications de Ia taille de Ia Sardine selon le mois.

    Evolution du % de chaque groupe selon

    le mois.

  • 34-

    Frequence des Tailles en % selon Tailles a L1 des Sardines des Gr. I et 0. le mois en 1946. mm. Gr. I Gr. 0

    mm. Juin Sept. Oct. Nov. 70 10 90 10 17 75 05 95 29 83 80 28

    100 156 108 85 148 105 05 175 141 90 214 07 110 26 88 122 133 95 233 36 115 220 225 75 284 100 143 109 120 460 88 27 134 105 129 152 125 182 100 08 92 110 57 174

    130 55 125 02 08 115 1-4 232 135 26 50 17 120 19 138 140 50 44 125 94 145 21 37 103 130 44 150 05 100 ll-8 135 07 155 88 85 140 07 160 12 29 1000 1000 165 25

    N. 210 138 170 12 m. 95mm. 115 mm.

    1000 1000 1000 1000

    Frequence du Nombre de Vertebres en % selon les Groupes et pour la totalite des Sardines etudiees.

    Nombrede vertebrcs 50 51 52 53 54 Moy. Fl N.

    Anchois.

    Gr. I. Gr. 0.

    Total

    0 0

    01

    134 174

    147

    256 637

    57.1

    Anchois du Golfe de Gascogne.

    315 181

    269

    La moyenne vertebrale de l'anchois du Golfe de Gascogne a ete definie comme suit:

    F age: Arne: Furnestin:

    4722 + 0290 N=74 4785 + 034 N=70 4,7108 + 0096 N=509

    Ces chiffres sont valables pour des lots preleves dans la region de Saint Jean de Luz. Personnelle ment, en Septembre 1944, dans cette meme region, no us avons releve Ia moyenne de:

    4,726 + 0205 N=100

    En OctoLre-N ovembre 1946 now' avons repete

    25 08

    12

    5222 5202

    5214

    0163 0177

    0081

    210 138

    765

    Ia meme analyse sur des echantillons venant de Ia region entre La Rochelle et les Sables d'Olonne ce qui no us a donne Ia moyenne de:

    4690 + 0152 N=200

    Cette derniere moyenne est franchement diffe-rente des moyennes precedentes qui sont toutes tres voisines (Fig. 3). Les tailles des deux lots que nous avons examines etaient egalement dissemblab-les (Fig. 4).

    Sans affirmer que l'anchois du nord forme une race differente de celle du sud du Golfe de Gas-cogne, nous attirons !'attention sur cette question que nous nous proposons d'etudier dans les annees a venir.

    Letaconnoux.

  • - 35- Atl. Slope

    200

    100

    10

    Fig. 3. Triangles de fluctuation de la moyenne vertebrale.

    A - a St.Jean-de-Luz B a La Rochelle

    Fig. 4. Repartition des tailles. A -a St-Jean-de-Luz OX-194-!l B -- a La Rochelle (X-XI-1946)

    Maquereau.

    Maquereau du Golfe de Gascogne. Peu d'observations ont encore etc faites sur la

    biologie du maquereau dans le Golfe de Gascoane. De 1941 a 1943, les chalutiers travaillant e~tre

    4540 et 4710, par les fonds de 200 a 300 m. ramenerent de petites quantites de maquereaux en Mars principalement. Ces captures denotent dans cette re~ion la presen:e de concen~rations de pre-maturatiOn analogues a celles que l on voit debuter a la meme epoque sur les fonds de 120 a 150 m. de !'entree occidentale de la Manche.

    Sur les fonds chalutes, ces concentrations etaient

    ;j*

    Anchovy, Mackerel

    Frequence Nombre des Tailles. de Vertebres

    mm. 1944 1946 de 1' Anchois. 50 02 N. 1944 1946 55 45 05 60 09 46 8 230 65 17 47 59 635 70 7.7 48 32 125 75 105 49 1 80 149 50 05 85 ll-0 90 101 100 1000

    95 109 04 100 123 17 105 128 60 llO 53 120 ll5 12 231 120 05 261 125 132 130 ll2 135 25 140 25 145 13

    1000 1000

    N. 413 234

    relati~ement peu importantes, mais quelques coups donnes entre 120 et 150 m. montrerent la presence de banes plus considerables entre Fevrier et Mai.

    On releve encore en Octobre/Novembre la pre-sence de maquereaux pres des fonds ce qui complete l'analogie avec le comportement du maquereau de la Manche et de la Mer du Nord.

    Sur les fonds de 150m. on trouve en Mars des individus dont la taille est de 30 a 40 em. et qui sont proches de la ponte. On a eo-alement releve la presence de maquereaux de 21 a 27 em. (1944).

    Letaconnoux.

  • - 36-

    Apports Moyens de 1941 a 1943 par Mois et par Chalutier.

    Mois

    J. F. M. A M. J. J. A. S. 0. N. D. m.

    Kg.

    05 150

    2630 150 10

    40 30 30

    240

    Mensurations du 6 em. N.

    21 1 22 18 23 69 24 62 25 25 26 8 27 1 28 29 30 2 31 32 1 33 3 34 5 35 13 36 15 37 11 38 14 39 5 40 2 41 1

    t. 256

    Argentine.

    0/o Nombre de sorties

    007 120 008

    002 002 001

    012

    47 53 56 55 62 49 56 59 58 62 62 67

    686

    au 24 Mars 1944. 0/o

    040 704

    2700 2410

    977 313 040

    078

    040 1-17 195 508 587 430 548 195 078 040

    10000

    (Argentina sphyraena ). Au debut de l'annee 1946 nous avons rencontre

    des argentines en grand nombre au sud de l'lrlande. Par contre a la Grande Sole et a la Petite Sole elles etaient rares. 1. Sud de l'Irlande. 5018. 9 25. 100m. 1 Mars,

    14 h. Temperature de l'eau a 30m: 104. 2. Grande Sole. 5017. 1051. 340 m. 28 Fev-

    rier, 19 h. 30. Temperature de l'eau a 10 m: 112.

    % ,., 0

    06

    06

    01

    Fig. 5. Pourcentage de Maquereaux dans les apports au cours de l'annee.

    N% 30

    ~I 25 50

    Fig. 6. Mensurations de Maquereaux en Mars 1944.

    3. Petite Sole. 4822. 906. 170m. 5 Mars, 21 h. 15. Temperature de l'eau en surface 117.

    La plus grande abondance d'argentines se trou-vait done sur le plateau continental a des profon-deurs de 100 a 120m.

    Toutes ces argentines, dont les tailles se repar-tissaient entre 15 et 25 em., etaient a un etat de maturite sexuelle a vance ( stades V a VI), un seul individu au stade II mesurait 15 em. En leur compagnie nous avons trouve des jeunes immatures

  • - 37 -- Atl. Slope

    de 7 a 10 em. et allant vraisemblablement avou un an.

    Les tailles moyennes des lots l et 3 sont respec-tivement de 211 et 197 em. Ces deux lots doivent avoir le meme age et la difference de leur taille moyenne s'explique par le fait que le premier est surtout compose de 9 et le second de d', les 9 ayant une taille moyenne superieure a celle des d' (203 contre 197 em.).

    La moyenne vertebrale est de 5262 -+- 0304.

    em.

    15 16 17 18 19 20 21 22 23 24 25 26 27

    t.

    1

    1 3

    19 21 27 24 14 8 1

    1

    119

    N

    20

    10

    Letaconnoux.

    3 d' 9 2 2 1 1 2 1 2 4 4 2

    21 15 12 14 9 5 9 7 4 l 2 1 5 2 5 2 3 3

    1

    61 46 35

    \l \ \ \ . . . \ ,'\ \' ' v '..

    13 15 17 em

    Fig. 7. Graphique des tailles. Argentina sphyraena.

    N. vertebres Etat sexuel

    51 1 II l 52 23 III 53 26 IV 2 54 5 v ll

    VI 61 t. 55 t. 75

    Lesser Silver Smelt, Grondin Gris. Grey Gurnard

    (Trigla gurnardus).

    Repartition des tailles.

    Dates:

    Origine:

    Engin:

    (en pourcentage)

    Juin 1945 Mars 1946 Golfe de Gascogne (cote

    des Landes: 40 a 80 metres) entre Saint-Girons etMimizan

    Chalut

    47 L.N. 430' W.G.

    N ombre d' exemplaires: 138 Chalut

    573 Tailles en em.:

    ll 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38

    Moyennes

    Modes

    Observateur

    Frequence O/o

    o:75

    075 l-45 075

    1375 3695 3040 940 215 215 075 075

    Frequence Ofo

    070 050 105 105 300 210 400 540 855

    ll-70 1010 1080 1115 1140 765 o-45 230 175 035

    --------------

    10000

    1745 em.

    17

    Let a con noux

    10000

    30-45 em.

    24-29-33 em.

    Forest

  • 39-

    Northern North Sea.

    INVESTIGATIONS IN 1946. The Scottish research vessel "Explorer" was

    commissioned in May and thereafter till December carried out combined hydro-biological and fishery cruises chiefly within the western sector of the North Sea and to the west of the Orkneys and Shetlands. Investigations were centred largely on trawling in order to obtain evidence from experi-mental hauls as to the actual condition of the stocks of fish for comparison with pre-war data and for confirmation of the commercial observa-tions during the latter half of 1945. Mesh of net experiments were also carried out to test the effect on the haddock stock of the 80 mm. mesh which was laid down at the Overfishing Conference in March 1946 as the minimum for North Sea and adjacent waters.

    Hydro-biological cruises across the northern gateway to the North Sea were made also by Danish and Norwegian research vessels.

    Belgium, Denmark and Sweden sent out ob-servers on commercial vessels operating the herring trawl on the Fladen and Gut grounds, samples of herring being retained for detailed examination ashore.

    A. Environment. The hydrographical conditions during 1946 were

    abnormal. Atlantic water did not penetrate the northern area in any considerable volume until the second half of the year and then mainly in sub-surface layers. This resulted in a reversal of the usual south-going stream along the western sector, of the North Sea and an effective closure to in-coming water of the Orkney-Shetland passages. Bathythermograph readings on the Scottish summer herring grounds during the Asdic experiments established a sharp thermocline approximately at 30 metres depth over a wide area. Exotic oceanic plankton species were in abundance and widespread in the northern and central North Sea. The appearance in numbers of the jelly-fish Pelagia perla was most noticeable while doliolids were widespread and abundant. On the other hand, the medusa Aurelia aurita was conspicuous by its absence.

    B. Fish Species. 1. Haddock. Age analysis established two year-

    classes of good survival, namely 1944 and 1945. The 1946 brood, however, so far as has been ascertained, is one of the poorest on record. The numbers of older and larger fish were much less than in 1945, the percentage of haddock over four years of age in the catches being almost negligible. 'I1his feature bears out previous observations on

    the high rate of mortality of the spawning stock. The poverty of the 1946 brooci seems to have had some relation to the abnormal hydrographic condi tions.

    2. Lemon Soles. In comparison with pre-war catches, a higher percentage of large-sized fish was observed in the post-war period under review. Ten-year-old fish were predominant in commercial landings and seven-year-old fish in the experimental hauls. The brood of 1941 was fairly well repre-sented, but that of 1940 showed poor survival.

    3. Herring. In collaboration with the Ministry of Agriculture and Fisheries and through the courtesy of the Admiralty, experiments on the use of Asdic for spotting herring shoals were carried out during the year in the Clyde area and off the Scottish north-east coast. The results on the whole were encouraging and with further technical refine-ments, the apparatus should be a most useful com-mercial acquisition.

    Apart from the two papers on racial studies included herein, little or no new research work of a biological nature was done on the fish themselves. The fishery of the local community of herring in the Firth of Forth was poor during the winter of 194.5-6, while during the recent winter of 1946-7 it was a complete failure. The causes of the decline in this fishery are being investigated. The search for herring larvae on the east coast of Scotland was pursued energetically during the spring of 1947 but, so far, the results have been entirely negative. It is possible that abnormally cold water, as has been observed on the Norwegian coast, altered the migratory route of the adult spawning herring, but so far (May 194.7), no definite information has been obtained as to their location.

    As a sequel to the meeting of herring experts at Aberdeen, effect has been given to the preparation of twelve monthly charts showing the distribution of European herring, their spawning times and places, and the quality of the fish. Scale samples have also been interchanged between the various workers, while those workers who have not previ ously adopted racial methods are giving them a trial. C. Fishing Gear.

    Mesh of net experiments, especially the effect of an 80 mm. mesh on the stocks of fish, were carried out by the Scottish research vessels, and the haddock data have been prepared for presen-tation at the special meeting of the Council in October 1947, on the "Effect of the War on the Stocks of Fish."

    R. S. Clark.

  • - 40-

    ENVIRONMENT.

    Hydrographic Conditions at the Northern Entrance to the North Sea in August 1946.

    By

    Jens Smed.

    D DRING August 24th and 25th, 19. 46, the Danish research vessel "Dana" under the leadership of Dr. A.. V e de I Tan in g undertook hydrographic investigations along a line from Helliso (Norway) to Unst (Shetland islands) - see Fig. l. The data will be published in the Bulletin Hydrographique pour les annees 1940-1946. A section showing isotherms and isohalines is given in Fig. 2. The positions of the stations are marked by vertical lines. Above each such line is indicated the number of the station, its position and the date when it was worked.

    To find the current velocity perpendicular to the section as well as the water transport through the section dynamic calculations were carried out on the basis of the temperature and salinity data. In the diagram Fig. 3 the velocity values are re corded for the various intervals of depths between the stations. These values were based on the sup position that the zero-surface - i.e. the surface where the horizontal pressure gradient equals zero - for an interval between two stations is situated as indicated by the bottom line of the interval in the diagram. Positive values indicate current to the north.

    Just below the bottom line in Fig. 3 is for each interval recorded a value for the intensity of the water flow through each interval. This value is in accordance with the stated current velocities. It will be seen that in the western part of the section an inflow to the North Sea of a little less than l km.3/hour takes place. It should be emphasized that this is considerably more than the normal in-

    flow. From calculations carried out by the author, which are not yet published it will be seen that the normal inflow in the western part of the section amounts only to about 03 km.3/hour. In the middle part of the section there is no significant current. In the Norwegian channel, especially its eastern part, the northgoing current reaches high velocity values in the upper layers. The stated values for

    Fig. l. Location of stations.

    the intensity of flow through the channel indicate a flow to the north amounting to about ] km.3/ hour. This value should, however, be taken with much reserve as one is probably not justified in taking the bottom as the zero-surface in the Nor-wegian channel. On the other hand the values for the current velocities will not, however, be altered to any considerable degree by a reasonable shift of the zero-surface.

  • Meter

    J wo~ 150 ~

    '""~ 2501 300

    350 .

    50

    100

    150

    zoo

    250

    300

    350

    Da6412 Da6411 Da6410 25.VJII 25.VIII 25.VIII

    6043' N. 6048'5 N. 6048' N. 0035'W. 014'\V. 016'E.

    S~dlond

    Da6409 25.VIII

    60047'N. 046' E.

    Da6408 25.VIII

    60047'N. jOJ?'E.

    -41-

    Da6407 25.VIJI

    6047'N. 1046'E.

    Da6406 2.5.VIII

    6046'3N. 218'E.

    Da6405 Da6404. 25. VIII 25. Vlll

    60046' N. 6046'N. 2-!5' E. 308' E.

    Fig. 2. Section giving isotherms and isohalines.

    Da 6403 24.VIII

    6046'N. 338' E.

    N. North Sea Hydrography

    Da 6402 Da 6401 24. VIII 24.VIII

    60045'5 N. 6046'N. 4009'5E. 4o31'E.

    Norwoy

    Do6\12 Do 6\11 Da 6410 Do 6409 Da6408 Da 6407 Do6406 Do6405 Da6404 Da6403 Da 6402 Da 6401

    -1 ~~- 2fe1. o~:c o~;;.-_ o;;c 40Wc - 6 -1 -3 - 1 0 .. - 1 0 20 ..

    O - 4 -1 -2 - 1 0 .. -1 0 7 ..

    - 2 0 -1 0 .. 0" 0 00~ ~------~-------4~------~-------4---------L-------L------~---1 ____ ~ ___ 0 __ " __ -+ __ 1 __ -4 0 0 0 0 0.1~ 00~~ o.o~-;

    -o s;;;:; o.o~:~ -0.3~:; - 01~;

    - 1 - 1 .. - 2

    0. -2.

    o .. 0" -1 '

    - 01 ~:,~

    O.Q ~:v~r 1.0~:~

    Fig. 3. Current and intensity of flow through the various parts of the section. Positive values indicate current to the north.

  • - 42-

    Hydrography in Scottish Waters.

    Consequent upon restrictions due to war after-math, operations of the Scottish research vessel during 1946, from May to December, were confined to the nearer waters of the northern and central North Sea, the Faroe-Shetland Channel and off the west coast of Scotland. Temperatures and salinities from surface to bottom were recorded at 124 positions, and surface drift-bottles to the number of 590 were set adrift at selected points. 96 of these have been recovered to date and thanks are extended to Norwegian and Danish colleagues for their kind collaboration in these experiments.

    In the Moray Firth area during the last week of May, sea temperatures from surface to bottom were about 1 C. above normal and salinities some 025 Oj00 below average. There was no Atlantic water present even in the lowermost layers of the outer waters of the Firth where normally it is in evidence at this time of year.

    These anomalies of temperature and salinity had diminished somewhat by mid-June in the outer Moray Firth area where there was still no evidence of Atlantic water at that period. Likewise in the Orkney neighbourhood, both to the eastward and westward, there was entire absence of oceanic influence in mid-June. Drift-bottle recoveries point to an anticyclonic circulation enveloping the whole island group, and temperatures and salinities indi-cate this to have comprised west Scottish coast, mixed with North Sea waters.

    Some of this mixed water was traceable as far north as the Island of Foula, west of Shetland, where only the beginnings of oceanic influence were noted in sub-surface waters. Atlantic influence was more pronounced, though still sub-normal for the season, to the north-west and north of Shet-land. Drift-bottle results for June in this area show a northward drift in operation from at least the Fair Isle region in latitude 5930'N. to the western shores of Shetland. On the east side of Shetland oceanic characteristics were stronger than to the north and west of the group. There can be no question that Atlantic water entering the Northern North Sea at this period came by way of the north of Shetland; none can have had access through the openings between Shetland and the mainland of Scotland.

    There was still no trace of Atlantic water in the outer Moray Firth, east Orkney and Fair Isle regions at mid-July, although temperatures con-tinued above average. The Shetland area, on the other hand, from longitudes 4W. to 230'E. and north of latitude 5940'N. was flooded with high temperature but relatively low salinity Atlantic

    water down to between 300 and 400 metres. Evid-ence of admixture with fresher water was marked to the north-west of Shetland out to mid-Channel where the average salinity in the uppermost 300 metres scarcely exceeded 3520 Oj00 except at an isolated position where 3530 O / o0-3532 / oo was recorded.

    All 28 drift-bottles recovered from July liber-ations along latitude 61 N. stranded on the coast of Norway. Routes embracing the Northern North Sea can definitely be ascribed to only two of these

    drifters, but on the other hand, the remainder, along with both earlier and later liberations, stranded all about the same period, namely in October-November 1946. Some of these certainly came from the North Sea and the weight of evidence, short of a detailed cartographical analysis of the records, inclines towards the postulation of North-ern North Sea routes for practically all of them. The oceanic influx to the Northern North Sea, however, during the summer of 1946 appears both from drift-bottle records and temperature and salinity observations to have been a very poor one compared with most years.

    Relatively high temperatures were observed in August in the sea areas west of Orkney and the Outer Hebrides. Atlantic water much diluted was present in sub-surface layers west of Orkney. Dilu-tion had undoubtedly come from west Scottish coast waters where low salinities of 3460 Oj00 and below were registered. Even to the westward of the Flannan Islands, practically on the continental edge, the concentration of oceanic water was found to be low. At more southerly stations off the Outer Hebrides the sub-surface layers were more decidedly oceanic in character, but dilution by fresher waters was still much in evidence.

    In the Central North Sea in September, off the mid-east Scottish coast, only the outer sub-surface waters showed signs of oceanic influence, with a thermocline established at about 30 metres' depth. At certain positions which would appear to have been on the boundary of the mid-east Scottish Coast Eddy, slightly sub-normal temperatures were observed in the uppermost waters. Elsewhere tem-peratures were nearly 1 C. above the average for the season in this area.

    During the month of October oceanic water predominated at all depths in the north-western area of the North Sea from latitude 58N. north-ward, except in the Moray Firth area from which it was entirely absent. There was again evidence from drift-bottle records of an anticyclonic circula-tion round Orkney, and later recoveries on both

  • - 4~)- N. North Sea Hydrograph}', Plankton

    Orkney and east and west Shetland shores point unmistakably to the operation during the last quarter of the year of a large anticyclonic system embracing almost the entire north-western area. Towards the end of the year this system seems to have extended southward at least to the Firth of Forth area, resulting in a reversal of the normal southerly current all along the Scottish east coast.

    Salinities off the mid-cast Scottish coast in Novem-ber strongly suggest the indraught into that area. and into the Moray Firth in the following month of indigenous Central North Sea waters, the whole mass tending northward as far as Shetland instead of, as ordinarily, passing south towards the Dogger Bank. This effect endured apparently until the middle of February, 1947.

    John B. Tait.

    Plankton in Scottish Waters.

    Plankton samples were taken in Scottish waters from June to December 1946. Details of the macro-plankton have been worked out from horizontal collections with 1 metre stramin nets, and the micro-plankton from vertical hauls with Hensen, Hjort, Standard fine silk nets and from samples taken by the plankton pump.

    The most noteworthy feature of the year's plankton was the extraordinary degree of penetra-tion into the Northern North Sea of the oceanic species, Dolioletta gegenbauri, Rhincalanus, Euca-lanus, and Pelagia perla. These species reached as far south as a line extending NE. from the Scottish border, and conditions in this area in September were such that doliolids were breeding there.

    To the north-west, north and immediately east of Shetland in July there was a community of oceanic species, including deep water and cold water forms as well as those from warm Atlantic water - Sagitta maxima, S. lyra, S. serratodentata, Eukrohnia, Ihlea (Salpa) asymmetrica, Diphyes bipartita, Meganyctiphanes, etc. By October the fauna there had only slightly changed and the distribution of oceanic species was much the same as in early summer,' although some of the species were no longer present and others were reduced in numbers (e.g. doliolids, Diphyes). A patch of Meganyctiphanes was still present north-west of Shetland but numbers were much diminished east of Shetland. Sagitta maxima, S. lyra and Eukroh-nia were still present. Sagitta elegans, which had been scarce in that area during the summer, was present in abundance there in autumn.

    The presence of Pelagia perla in profusion throughout the whole area affected by oceanic water is unusual and was accompanied by the commensal Amphipod Hyperia galba. Aurelia aurita was almost entirely absent in the 1946 plankton in the area investigated. Off the east Scottish coast in September Sagitta elegans was dominant and was mixed with the oceanic fauna. S. setosa occurred in numbers only south of a line extending NE. from the Scottish border. There was some mixing of the fauna in the region where the incoming oceanic water abutted against the indigen-ous North Sea water, and in these places the North

    Sea fauna (S. setosa, Corycaeus anglicus, etc.) was generally near the surface and the oceanic fauna below.

    The usual abundance of Stage V Calanus fin-marchicus was found in early summer in the Faroe Channel and to the west of Shetland and Orkney and off the west coast of Scotland. Calanus was generally distributed over the North Sea area investigated but only in moderate numbers except in local areas. Pseudocalanus was common through-out the investigations. Candacia arTTULta was more than usually abundant in the northern North Sea where it was associated with Sagitta elegans.

    The main spring flowering of diatoms was largely past before sampling began, but a patch of mixed Chaetoceros spp. was found off Kinnaird Head in June. Rhizosolenia alata var. gracillima occurred to the north and east of Shetland in great abundance in July and with it were Ceratium tripos and the Radiolaria, Acanthochiasma and Aeantho-metron. Although the Rhizosolenia had become much reduced by September the Radiolaria persisted and could be traced into the North Sea where Ceratium macroceros was extremely common. Guinardia flaccida was extremely abundant, off the west and north coasts of Scotland, in August.

    The absence of data from the spring months of the year means that the major spring spawning of fish was unassessed in the 1946 plankton. The summer figures of larval fish (clupeoids excepted) were much below those of 1939, although they were not seriously different from those of 1938. Lemon sole and hake were the dominant commercial fish larvae present; larval hake were, in fact, more numerous in 1946 than in either 1939 or 1938.

    The earliest catch of autumn spawned larval elupeoids was at the Pentland Skerries in rect-angle B 16 c in July, and large numbers were taken in August immediately west and north-east of the Orkneys, in rectangles A 16 b and B 17 d - much earlier than the records for 1939 and 1938. The total average of autumn-spawned clupeoid larvae was not very much less in 1946 than in 1938, which was a relatively good brood year for autumn spawning herring. No total figures from 1939 are available for comparison.

    ]. H. Fraser.

  • - 44-

    THE FISH SPECIES. Lemon Soles.

    The 'Explorer' records include fish caught in the small mesh covering the cod-end. On grounds to the south of Rattray Head only four small lemon soles were taken in the small mesh and in the Moray Firth only eight fish were so taken. Even if these captures are ignored it is clear that the average sizes of lemon soles taken by the research ship in the Moray Firth and on grounds south of Rattray Head are much smaller than the correspond-ing averages for commercially caught fish. Simil-arly the age analysis of both sets of data show the commercial catches to be generally older than those of the 'Explorer'. The explanation of this seems to be that the 'Explorer' operates both in

    territorial as well as in extra-territorial waters and that the inshore grounds do not support the large numbers of older and larger fish which are found on offshore grounds owing to the inshore grounds having been fished throughout the war_

    The commercial catches emphasize the import-ance of the 1936 brood, particularly off the east coast of Scotland, with the 1939 brood as a close second. The 'Explorer' catches, on the other hand, show the 1939 brood as the outstanding one with that of 1941 at least up to the average strength. Both commercial and research vessel records agree with regard to the comparative poverty of the 1940 brood.

    Table 1. Size Frequencies of Samples from Commercial Trawlers. Locality

  • ----------------------------------------------

    - 45- N. North Sea Lemon Sole, Herring

    Table 3. Size Frequencies of 'Explorer' Catches. Locality

  • -46.-

    ment pour combien ces deux regions interviennent invariablement la regiOn du "Fladen" comme chacune dans le poids total debarque au cours de origine de leurs peches, alors que tout au plus le la saison. En effet, nos patrons pecheurs indiquent tiers de leurs apports y a ete capture.

    Table 5. Repartition mensuelle des apports.

    Nombre Nombre Journees Po ids Po ids C. V. Poids par

    Mois de de de total n;oyen,p. dev~lop-journee

    Wilv1res vovaoes peche de barque JOUrnee pes pourl C.V. ' tJ de peche developpe

    Juillet 1 1 7 55,220 7,888 3,360 16-43 Aout 23 46 208 2,618,266 12,588 82,145 3187 Sept. 44 113 587 5,197,860 8,855 197,840 2627 Oct. 35 72 427 2,725,083 6,382 174,980 1557 Nov. 14 21 187 291,238 1,557 97,270 299 Dec. 4 4 29 12,875 444 14,400 894 Total 47 257 1,445 10,900,542 7,544 569,995 1912

    B. Statistiques biologiques. Fladen: 8 echantillons en aout et 1 en septembre. Au Gut: les 5 echantillons en septembre.

    Le materiel analyse comprend 14 series d'echan-tillonnage qui comptent au total 643 harengs. 9 series, ou 398 individus, ont le Fladen pour ori-gine et 5 series, ou 245 individus, le Gut. Tout le materiel a ete preleve en a out et septembre: au

    Le materiel recueilli sur les deux lieux de peche est traite separement. Ce scindage doit permettre de verifier si nous avons a faire a une meme communaute de harengs sur le Fladen et le Gut.

    Tableau 6. Longueur (recommandation d"Aberdeen 1946): Repartition pour 100.

    em. 20 21 22 23 24 25 26 27 28 29 30

    Fladen 10 13 45 113 332 304 138 38 07 Gut 04 41 41 12 41 135 269 322 112 20 04 Fladen +Gut 01 22 16 12 43 12] 308 31-l 127 31 06

    Stades des Gonades (Signes de Hjort- Lowestoft 1930): Repartition pour 100. Stadcs observes I li III IV v VI VII Vlll-II Mode Fladen 13 18 93 229 580 4-3 10 15 v Gut 29 1-4 61 126 608 139 24 08 v Fladen +Gut 19 12 81 190 591 79 16 12 v

    Quantite de Graisse mesenterique (Signes de Hjort): Hepartition pour 100. Graisse observee 0 1 + M Mode Fladen 271 387 239 103 1 Gut 469 322 114 94 0 Fladen + Gut 347 362 191 99 l

    Age - FnSquence des Classes de Recrutement: Hepartition pour 100. Anneaux d"Hiver 1 2 3 4 .5 6 7 8 9 + Mode Age 2 3 4 5 6 7 8 9 10 + du Classes de 1944 1943 1942 1941 1940 1939 1938 1937 1936 Anter. J:ombre Recrutement d anneaux

    Fladen 21 67 ll-0 239 153 ll-6 132 95 52 5 Gut 17 88 146 123 240 123 88 76 35 41 5 Fladen +Gut 06 44 95 ll-5 239 143 107 ll-3 74 48 5

  • Tableau 6 (continue).

    -47-

    Age et Taille. Longueur moyenne. (en em.)

    N. North Sea Herring

    (a) Mensurations au mm. (b) au em. inferieur (correction + 05 em.)

    Moyenne des harengs

    Classe 1943

    " " "

    1942 1941 1940 1939

    Fladen Gut

    229 223 250 253 261 266 269 269 275 275

    Fladen +Gut Fladen Gut Fladen +Gut

    225 232 224 226 252 250 255 253 263 260 267 263 269 269 270 270 275 276 275 276

    (Recommandation d'Aberdeen, afin de comparer les moyennes calculees d'apres les deux methodes; l'ecart s'avere tres minime ou meme nul.)

    Longueur de la premiere Zone de Croissance ou Valeur de L1 (Methode Lea). Valeur moyenne de L1 pour chaque classe de recrutement en mm.

    Nombre d'anneau:x d'hiver Moyenne Nombre Orioine b 2 3 4 5 6 7 8 9 generale d'individus

    Fladen 119 118 122 120 129 114 113 107 118 322 Gut 112 119 123 119 130 119 108 103 119 166 Fladen +Gut 114 119 123 120 130 115 112 106 118 488

    Vertebres. Frequence de chaque nom bre de vertebres: Repartition pour 100. Nolllbre 54 55 56 57 58 Nombre Mode

    Moyenne de V ertebres d'individus vertebrale

    Fladen 07 60 435 447 50 398 57 56-4724 Gut 0-4 33 522 388 53 245 56 564531 Fladen + Gut 06 50 468 425 51 643 56 564650

    Vertebres cervicales ou hemaux a arc non clos.I) Frequence de chaque nombre de verte bres cervicales: Repartition pour 100.

    Nombre 22 23 24 'Y 26 Nombre Mode Moyenne -J d'individus Fladen 35 296 467 186 15 398 24 2385 Gut 37 339 478 110 37 245 24 2377 Fladen +Gut 36 313 471 157 23 643 24 2382

    1) Les risques de brisure de Ia piece transversale du premier arc hemal out pu etre ecartes. Apres le premier arc hemal completement clos out n'a pas trouve d'autre qui l'et