SEA LAMPREY

Co urtesy of Michigan Conservation D partment

UNITED STATES DEPART MENT OF THE INTERIOR

FISH AND WILDLIFE SERVICE

BUREAU OF COMMERC IAL FISHERIES

Fishery Leaflet 580

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tan l

FI H A

T PARTM IT ' T , I

daH,

' RVI E , la r n F . P a utzk, ommi.,sloner

B RE A OF OMMER IAL FI HERIES, D ona ld L . McK ernan. Director

Sea Lamprey

By

LOLA T . DEES

Fishery Leaflet 580

Washington, D.C . August 1965

CONTENTS

In roduc ion .....

Effec of lampre . a acks on he fishery

Coopera ve researc n 0 contro_ :he lampre

,a ra ory.

Spa '"Ding ..

Larva lampreys .

Adul lampreys .

'alue of lampreys . ,

Contr o of ampreys .

Re s oring he lake trout

Refe r ences ..

Pa e

2

3

4

4

Sea lamp rey

By

LOLA T. DEES , Edito r

Bureau of Commercial Fisheries , Branch of Reports Washington, D . C .

INTR ODUCTION

In 1829 when t he engmeers flnlshed the Welland Canal which connects Lake Ont ario wit h Lake Erie t hey t hought they we r e providing a passage for ships only . They could not know t hey were lett ing in a "monster " fro m t he Atlant ic Ocean , t he sea lamprey , which about a hundred years laterwastodestroythe 10-m lllion - pound lake tro ut f i s hery of t h Great Lakes .

The sea lamprey, Petromyzon marinus , is found in the North Atlantic Ocean from Iceland and northern Eu rope to northweste rn Africa and from the Grand Banks and Gulf of St. Lawrence to northern Florida . The adult lamprey, onc e found in marine wa t ers only, has becom e w e ll es tabli shed in the lakes of wes tern and northern New York and in the

I Great Lakes. No one knows when the lampreys, m embe rs

of the family Petromyzonidae, fir s t moved into the Finge r Lakes of New York S tate , whe r e they abound. They probably cam e from Lake Ontario t h rough the canals b e t ween Oswego and Buffalo . .

Sea lampreys move each spring from the Atlantic Ocean into the coastal streams of E urope and No rth Ame rica to bulld nests, d l' posit eggs, and die. Some, howe ver, deserted the Atlantic Ocean to live in the fres h wate r of Lake Ontario, feeding on it s fish, spawning, and dying in its tributary streams. l\"iaga r a Falls pr e v e nte d the l ampr eys from migrating i to the other Gr eat Lakes. Howeve r, i n 1 R29 the Canadian Gove r nment finishe d the Welland Ship Canal, which provided the lampreys a route a r ound Niagara Falls.

E ven after t he canal was completed, the lampreys se e m t o have been slow in estab­lishing the ms elves in Lake E rie . The first lamprey was caught the r e in 1921 . They did not thrive in Lake Erie as t he wate rs were too warm and the spawning conditions poor . By the 1930 ' s t l,ey reached Lakes Hu ron and Michigan, wh re the food supply, cold wa te r s, and clear, grav el- bottom ed tributary streams wer e id e al for growth and survival. Then they moved to a r d Lake Superior, but the dam and t he navigation locks at t he head of St . fary's

iv r slowed t he r ate of invasion into th u; la Ke .

Revis ion of Fl her ' 1 eaflt.'t -lQl, larch l QbO.

Howeve r, enough lampre ys arrive d In th lak to es t ablish a rapidly growing popul a ti o n . T h first specimens we r e taken off Isle Ro y al,' a n d Whitefish Po int in 1946 .

EFFECT OF LAMPREY ATTACKS ON THE FISHERY

The effect o f the lamp r y atta cks on t ill' lake trout, the most priz.e d food fi sh a nd t h.· backbone of the fishing industry o f t h t' Gr"a t Lakes, was devastating . For th .. I O- yea r p"r lOd of 1930 - 39 fishe rm e n too k a n nu, lly abo u 5 million pounds of la kE' trout fr o m l.ak ,· Hu r on and the same amount fro m Lak.· Ilchl!!au . By 1950 the total catch in bo t h lak!" s \~ aS onl y about 0 . 5 million pounds -- a dec li ne o f Q') pl' r­cent . By 19 6 0 t he catch am ount pd to I .. s" han 2 , 000 pounds . In La kp Su p, rio r ca t ch.·" d,· ­clined r apidly comm t' n c ing In I Q") 3. By I It u the catch am ou nte d t o only 10 p.· r et·n t f 1\1" ave rag e fo r t he 10 - yea r p" rlod I Q·il -

The hr pr e ys no t only b r ought h v th .. large, pl" ntiful la kp tr ou o f Lal<,·s Ihro'1. , Michigan, and Supe rio r, but t rwy p r "Y"n f •• ,..IV _

ily on the large r chu bs a n d wlu t ,·fl.,h . -; r.t· • species, like the la k!" tr ou t, Inhabit th.· det ! wate r environme nt which IS dlso t h .. IdlY I-'f< )',,'

domain . As a res u lt o f tr(' !amp r .·y In\'a.,lr",

comm e rcial f i s ht> r ml'n o f t n" I r e" i! t r • dq

lost an a nnual i ncom.~ o f rr Off' t haI. - k n , .I Jr • •

Loss e s t o othe r channels in t hO" rad.·..1 1 ~

sport fis he ri e s cannot Oc c"tlmd .. d .

COOPERATIVE HE ' EAHC.H 10 CONTROL THE LA~tPHFY

T he Gr e at La1q> " St :l t ." _ .:>rl< , I "n', -sylvani a , OhIO , ,lichlgan, Indl1nd , 1.11n 1 ,

Wisconsi n , and • finn" "o t a) , tr,t> rO\'ln<')( O ntar io and t he Fed~ r a~ C )V" :-nrr "'lt f Ca na da a n d t h.· CniteCl S .l t t' ttl\", n e ffo rt s t o save h.> 1al<(' t r out f:- ')fT r, . de struc t ion . In 1 -1 th L 111 Cl ') In Canada bf'gan coop(' r a 1 \ '('

t o find mpan" to cont:-o: Sept mbe r I , I ~5; , p,. ... Jo m actIOn and t hl' G r a L m j,," lon ~a,. t' 'il In 1 ')

Effective methods for controlling the lam­prey i n the Great Lakes co uld no t be d e v e l oped until scientists l ea rned more abo ut its life cycle. They thought that during ce rta in p e riod s of its life it might b e vulnerable to m e thods of control. From studies they found that lam­preys spend 12 to 20 months in the l akes and in l at e winter cong r egate in bays andes tuaries of rivers to mature the ir sex products. Prio r t o spawning, the sex glands g ro w e normously while the muscles, skin, and eyes degene r a t e . The digestive tract shrinks , and t he lampreys do not feed but live on their s t o r ed fats and body tissues.

NATURAL HISTORY

Spawning

After t he streams warm to about 40 0 Fahren­heit the lampreys ascend those that contain gravel, clea r wate r, and a moderately strong current. The spawning m i gration may last 20 week s.

When a satisfactory spawning site in the stream has b ee n chosen, a male lamprey star ts building a nest and is joined bya fema l e , who he lps in the c onstruction . They clea r a

small a r ea , picking up stones w ith the ir mouth s and piling th e m i n a cr e scent-shaped mound on the downstream side o f th e n e st .

A ft e r the nest is finish e d and the water is wa rm eno u gh (o ve r 50 0 ) spawni ng b egins . T he f e mal e , which l ays an average of 6 1,500 egg s , deposits a few eggs a t first, and the male at onc e fertilizes t hem . The curr e nt carries t he eggs t o t he rim of the nest , whe r e they l odge in the spaces among the stones. Then th e f emale l ays another batch of eggs and the process i s repeated . The pa ir continu e laying and f e rtiliz ­ing eggs u n til they a r e spent--spa wning may tak e from 1 t o 3 days - - and then both di e wi thin a few hours and decompos e rapidl y . The lam ­preys that have no oppor tunity to spawn die also .

Larval Lampreys

Less than 1 percent of t hese heavy, small eggs ha t ch . Depending on the water t e mpera ­ture, ha t ching occurs in 2 to 3 weeks.

The newly ha t ched la rvae r emain in the nest until about t he 20 t h day . Then, about a qua rte r of an inch long, they drift downstream to quiet waters. In the soft bottom each larva digs a bur r ow that will be its horne for about 5 years unless erosion washes i t away. Throughout the ir l arval life the young lampreys, termed am ­mocetes (fig . 1), are blind and ha rmless. They

Figure l.--Stages of developme nt in the sea la mprey of the Great Lakes . A. An eyeless la rva 1 3/ 4" lo ng and about 1 year old. B. A 3- yea r - old larva 4 1/ 2" long in the nonparasitic life history s tage. C. A juve nile parasitic lampre y wh ich recently meta morphosed fro m the nonparasitic form.

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suck food, mainly microscopic organisms, from th wat r passing the mouth of the bur ­r ow. A filt e ring apparatus in the throat keeps out debris and passes food organisms to the dig e stive tract.

After about 5 years each larva develops large prominent e yes, a round mouth lined with horny teeth, a filelike tongue, and en­larged and unpair ed fin s . Its slim body, with a soft skeleton of cartilage r ather than bone, becomes dark blue above and silvery white beneath . Now 4 to 7 inches long , it may emerg from its burrow when late fall rains

rai se the stream level , bu u,ually It until the spring ice br akup and hl h before migrating down tream 0 th It will fe ed there upon the blood , bod' and dissolved n sh of fish, its sol, food .

Adult Lampreys

This jawless predator, whlch does no chool , attaches its suckerlike mouth (Ii . 2) to almo t any part of a fish . Sometimes s v ral ldrr ­preys feed upon one fish at the sam t1m .

Fi ure 2. -- l ou[h of [he sea lamprey \\hlch is I1n~d \\\[h horn} ["erh. In Ihl Len r r [he mouth is [he raspin' lOnrue .

.3

The vict im t h ras he s a bout v iole ntly, but rar e ly s h akes off t he lamprey. The strong t ee th and the r as p ing tong u e soon p e n e trate the fish's scales and skin. L amphr edi n, a substance in the lampr e y ' s sa liva , d i ssolves t h e t o r n fl e s h and k e e p s the b l ood from clo tting . Feeding s t ops w h e n t he host fish die s o r t he l am pre y becom e s g lu tt e d . The lamp r ey may r e m a in a ttache d to a fish for w e eks , b ut some fish ma y die i n as few as 4 hou r s . If a fish esc a pes , it is scarre d s o badl y it is often u nma r ke t ab l e .

F ee ding upo n a succ e ss io n o f fi sh, the l am ­p r ey, which d e stroys no less t han 2 0 pounds o f fi sh i n i t s life , g row s r a pid l y, attaining a l e n g t h of 12 t o 2 4 i n c he s and a we ig h t o f abo u t 8 o unce s. A lam p r e y r a r ely we i gh s mo r e t han 1 pound.

VA LUE OF LAMPREYS

Efforts t o fi nd comme rcia l u ses for t he l amp r eys t o c ompens a t e f o r t he de struc tio n they ca u se were u n successful. They a r e n o t pa latable t o t he peopl e of t he Uni t ed Stat e s although they a r e ea t en i n many E uropean countries . Ana l yses i ndica t e t ha t vi tam i n A potency and o il y i e l d o f t he l a m prey are m uc h too low fo r c omme r c i a l expl o i ta t ion . B i o ­l o gical suppl y houses r equi re onl y a few as study specimens.

CONTROL OF LAMPR EYS

Knowledge about the l amp r ey , wh i ch ha s no known na t ural enemies , s u ggested seve r a l po s ­sibilities fo r control. The r esearche rs f o und that the most vul nerab l e pe r iod s in the l a m ­prey's life are when it i s in the s tr eam a s a larva or a young mig r ant and l a t e r when it e n­ters the stream as an adul t t o s pawn. Effo rts were made to prevent adult lampr eys f r om en ­tering str eams to spawn. Me c hanica l we irs , insta ll e d fo r thi s purpose a s physica l b a rri e rs to mig r a t ion , proved expens ive a nd und e p end ­ab l e and flash fl oods washed t he m o ut.

The r esearche r s the n d e v e loped a combi­nation of mecha n ical tr ap s and e l ectrical barriers. An e l e ctrica l fi e ld p r odu ced i n a stream by e l e ctr i c al barrie r s was found t o b lock t he u pstr e am m i g ration o f l amp r eys . These e l ec trical barr ie rs w e r e supe rio r to conventional we irs a s t he y we r e les s vul ­n erable to b e ing w as he d o ut by floods . They d i d not clog w ith d e bri s and the y we r e cheape r t o ins t all and main tain . Fish and s ome lam ­p r eys ent e r trap s plac e d at each e n d o f t he elec tr ica l barri e r w hile othe rs pene tr a t e t he elec trica l fi e l d and ar e k illed. A d iffe r e nt typ e o f barrie r , w hich i s e n e r gized b y p ul sed , dir e c t - c urre nt e l e ctric i ty, i s use d in streams whe r e move m e nts of i mpo r ta n t fo o d fi s he s c oinc ide w ith t h e lampr e y m i g ration. T h is

4

device guides the fish and most of the lam­preys into traps where they can be sorted and separated. The fish are passed upstream and the lampre ys destroyed . An e lectric barrier (we ir) is sho w n in figure 3.

A tte mpts we re made to stop the downstream m igration of juve nile lampreys. Mechanical, i n cline d- plane s c reens that strain all of the w ate r of a s tre am were installe d. These are e xtr e m ely vu l ne rable to flo ods and accumu­lat ions o f deb ris, which occur dur i ng the h e i ght o f t he down s tre am m igration of lam­p r eys .

R e placing t h i s t ype o f s truc t u r e wit h d e vices d e signe d t o elec trocute immediate ly all d own­s t r e am mig r a n ts is no t econom i c ally fe asible . Vo ltag e s t hat kill fish only s tun y ou ng l am p r e y s and e n o ugh e lec tricity to kill l ampr e ys at this stage would cos t an exo r b itan t am ount .

T he r e s e a r che r s next co n sid e r e d us ing s e ­l e ctive pois o ns to k ill juvenile lampr e ys. Aft e r 3 yea r s o f t e sting some 5 , 000 chemica ls (fig . 4 ), t he y found that h aloge na t e d ni tr ophe no l s succe ssfully k ill la r vae in s treams , bu t d o n o t h ar m fi sh .

O ne o f t he s e chem i cal l a mpr icide s, 3 -trifluo rm e t hyl- 4 - ni t rophe nol , was use d t o de stroy lampr ey larvae in s t r eams tr ibuta r y to L ake Supe rio r . Applica t ion o f t hi s chemical into lam p r e y i nfe ste d stream s r equi r e s great s k ill a n d p r e cision by r es e a r ch t e ams . T he p r o c e dur e first i nvolve s a s t r e am su r ve y with p o rtable e l e ctric s h ocking d e vic e s t h at d rive burie d lampr e y la r va e ou t o f t he bo ttom fo r captur e and counting . A t wo - ma n c r e w makes t he surve y, and a r e co r d is mad e of t he a bund­anc e and dis tr ibution of la r vae . If la r vae are p r e s e nt , o t he r b i olog i st s map t he s tr eam , m e asu r e w a t e r flo w s a t a n u mber o f si tes , r un ana l yses o f the chemic a l p r ope rt ies o f t he wat e r, and de t e r m i ne t he po ints whe r e t he c hem i cal should be intro duced t o p rov ide compl e t e cov e r a g e .

J u s t p r io r t o treat me nt, a t e st i s run in whic h l amp r e y lar v a e a n d gam e fis h ar e p lace d i n a s e rie s o f j ars cont a ining ae rate d stre am w ate r a t t he p r eva i ling t e m pe ratur e . Into t he jars va r y ing amou n ts o f l am pricide ar e adde d to de t e r m ine t he conc e ntration and tim e of exposur e t ha t should b e us e d to obtain a compl e t e ki ll of l a mpre y larvae and a m inimum l o s s o f game fish.

O n ce t hi s pre treat me nt information is col ­l e cted a n d a n a lyzed , l a mpricide is introduc e d by propo rt ioning pum p s into an infested stream a t a r a t e so t ha t t he d e sir e d concentration is a c hieved t h r oughout the w ate r course. C he mi ­cal t e st s are m a d e at numerous site s during t he pe riod of treat me nt to e nsure that the con ce ntration of l a mpric ide is ade quate.

Aft e r the tr e atm e nt, biologists traverse the stre am w ith e l ectric shockers to check on the pre s e n ce of live larvae . Seldom are live larvae

F igure 4. - - A bio­assay section of th labo ratory a t Ham mo n d S a y, M i c h., which is used to scr een se­lectiv chemi­ca ls for la m­pre contro l.

5

near 1 udin ton, left , the alternatln curr ,nt 1 trod s ar suspend d upstream to prevent thL passa e of fish and lampreys. [)ownStrlam on the rl ht Is a suspend ·d dlr ct current electrode arra} uSld to

guide fish and lamprq5 ml rat­Ing upstream Into the two trap .

fo nd bec aus p of h e c ar e ake n in tr e a ing ~ :-.p ,,~r p a m . If many live la rvae ar e found, tr.e 5 r ea m is re - r eated .

Chpmical c o n rol ope r a ion s by Canadian a n d 'm ed Sates r es e a r ch t e ams be gan on " r pa • " tr ib ta ry t o La ke Supe rior in 195 . Bv ~).,,, P!'.d o f 1 ,..0 , c he mical t r ea tm e nts we r e corrp.ptpc on ~2 "t r e ams . An additio nal 53 lam ­p r p',' lr:fp st pd 5 r f' ams we r e tr ea t e d, and some "t :- earn" wp r e r e - reat e d by 19 5. The result o f t'.:" (or.tr o: p ffo r "~'as fi s t evident in 1962 ,~rpr. t p SILe o f he adult lampr ey population r!('c::n"d -2 pe r c ent ove r the 195 7 - 61 l e v e l. :r. ." j ar.d I yEA t he abundance o f adult lam ­') , "y" lnc r pa s pd s li g h tl y , but r ema ined 77 pe r­Cf'n t \-)e:0 '. t na o f 19 57 - 1 .

GOOd p r og r es s has bee n made i n tr e ating ,Irrp rt"( lr.f e :; ed st r e ams t r i b u t a ry t o La ke .. :ir' I~lr •. By t he e nd o f I 6 -1 , 7 str e a m s had

L f Pr: ., lccP !:i!:ifull y tr e ate d . It is an ti cipated t 'It th.- r ema Ining Z I st r e ams w i ll be chem i -

I: y t r ed pd by t he l att e r pa r t of 1 Q66 . The r e ­If~"r ~o r '~ w i ll co mrr p nce in t he Lake Hu ron I p·a . I. a dd lt ior. , biologists will c he m ica lly '~"1' "lnY r P lnfe st e d streams t r ibu tary to

," ,>ww r io r and /l.1ic h igan be fo r e lam pr e y I:" If' l r e old p no ul:! h t o metamo r p hose a nd

,I', t)thela k f's.

REST ORING T HE LAKE TROUT

It l~h r educpd substant ially, it is no t ~. ~ '1P nf' r hp lam p r ey po p ulation is low 1': to pf' r ml com ple te r e cove r y o f t he

I'" tr"ll t popula t ion . Howeve r , s ince 1961 "" : .. ' t r out popu latio n h as r esponded f a vo r-1) h' ) r .·dele, d lam pr ey p r e dation . Old e r and d r ,:' r r ')ut a rt' mo r e a b undant, and a dec line

" lccu rp d In t hp inc idence of f r e s h la m ­'r(')" ~'ound" on tr ou t.

To ,lid In " · ,,to ring lake trout, 10 .7 mi lli o n It( h" r \' - r pa r f'd ypa rLng t r out, p r oduced in t It.- , f pd" r al , a nd P r o v i ncial h atche r ie s, IV,' ,-pn plant e d in Lake Supe r io r sin ce 19 5 8 ,

I' 1<; "!:itiml , 1 t ha t 3 .-! million t r ou t will b e .. ) t<t'd In . .1K.'S S u pe rio r and M ichi gan in t he

,1'1' of 1 S . The past plant i n gs in L a ke •• p'- rlor n1ve bee n !:iu c c e ssful , and t hese fis h

'10.' c.om!'rl,,!' t he b u lk o f the younge r fi sh in t , Pit(', •

R E F E R E CES

) r'il , (. \ \ ~.CH.D \ . -/.. . I'h p -p po r abl .. fee ders fo r mete r ing

c. \-,-mlcl1 int o s tr pams fo r cont rol o f ,-a. rrp rt·y . P r og r . FIsh - Cult . 24(4 ):

• -0 - I l~. I I l.E .• A • E,

''>lJ. \ r 1 hI sto ry o f t h sal mp r y, I , • r omyz.on m nnu s , in Michig n . l.J .5 . f- \ cli. Serv. , ~pec.. SCI. R p . F s . 'ie;. II. ~ ~ p .

6

APP LEGATE , ER 0 C ., JOH H . HO ELL, and MA"NI G A . SMITH.

195 . Use of mononit r ophenol s containing halogens as selective sea lamprey lar­vicides . Science 12 7 (3294) : 336 - 338 .

APPLEGATE , ER 0 C ., JOH H . HOWELL, J AMES W. MOFFETT, B . G. H . JOH SON , and MA l I:'\G A . S 11TH.

1961 . Use of 3- trifluo r methyl- 4 - nitr ophenol as a selective s ea lampr ey larvicide . Great Lakes Fish. Comm ., T ech . Rep . I , 35 p .

A PPLEGATE, VER 0 C ., and EVERET T L . KI:\'G , JR .

196 2 . Compa rative toxicity o f 3 - trifluor­methyl- 4 - nit rophenol (TFM) to larval lamp r eys and eleven species of fis hes . T ra ns . Ame r . Fish. Soc . 91(4 ): 342 - 345 .

A P P L E GATE, VERNO C ., and JAMES W . MOFFETT.

19 55 . The sea lamprey. Sci . A m e r. 192 (4): 36 - 41 .

B A LD WI " l\'ORMAN S . 1963 . Closing in on a silent kille r. Con­

s e rvationist (State of N . Y . Conse r v . De p.) 17(3): 30 - 32 .

196 4 . S e a lamprey in the G r eat Lakes . C anad . Audubon 26(5 ): 142 - 147 .

B RAEM, ROBERTA., and WESLE Y J . EBEL. 19 6 1 . A back- pack shocke r for collecting

lamprey ammoce t es . Prog r. Fish- Cult . 2 3(2): 87 - 91 .

D ANIELS, STACY L ., LLOYD L . KEMPE , THOMA S J . BILLY , and ALFRED M . BEETO •

196 5 . Detect ion and me asurement of o r ganic lampricide r esidues . Great Lakes Fish. Comm ., Tech . Rep . 9 , 18 p .

EBEL, WESLEY J . 196 2 . A photoelec tric amplifier as a dye

detector . Great Lakes Fis h . Comm ., Tech . Rep . 4: 19 - 26 .

ESCHMEYER , P A UL H . 1957 . The nea r extinc t ion of lake trou t in

Lake Michigan. Trans . Ame r . Fish . Soc. 85 (1 955): 102 - 119 .

HILE, R A LPH • 19 57. U .S . Fede ral fishery r esea rch on the

Great Lakes through 1956 . U .S. Fish Wildl. Serv ., Spec . Sci . Rep . Fish . 226 , iii + 46 p .

H O VE LL, JOH H ., EVERETT L . KING , JR., A LLE J. SMITH, and LEE H . HANSO •

1964 . Syne rgism of 5, 2 1 - dichlo ro- 4 1-nitro _ sa l i c y lanilid e and 3 - trifluor me thyl - 4 -nitroph enol in a selective lamprey lar ­vic ide . Great Lakes Fish . Comm ., Tech . Rep . 8 , 21 p .

KA A Y A M A , RICHARD K . 1963 . T he us e of alkalinity and conductivity

m ea sure m e nts to e stimate concentr a ­tio n s o f 3 - trifluorm e thyl-4-nitrophenol r e q ui r e d for tr e ating lampre y streams . G r ea t Lakes Fi sh . C omm . , T ch . Rep . 7, lOp. ~

)

)

McLAI , ALBER TO L. 1952. Dis as s and parasites of t he s a

lamprey, Petromyzon marinus, in the Lake Huron Basin. Trans. Am r . Fish . Soc . 81 : 94 - 100 .

McLAI , ALBERTO L . , and WILLIS L . NiELSEN.

1953 . Direc ting the movement of fish with electricity. U .S . Fish Wildl. Serv ., Spec . Sc i. Rep . Fish. 93 , iii + 24 p.

McLAIN , ALBERTO L . , BERNARD R . SMITH, and HARRY H . MOO RE .

1965. Expe rimental control of sea lampreys wit h electricity on the south sho r e of Lake Superior, 1953 - 60 . Great Lakes Fish. Comm ., Tech. Rep . 10 , 48 p .

McVEIGH , EDWARD J . 1958. Showdown in the Great Lakes . Dow

Diamond, J une, 6 p . MOFFE TT, JAMES W.

195 8a . Attack on t he sea lamprey. Mich . Conserv . 2 7( 3): 21 - 27 .

1958b . Lake trout and sea lamprey. Conserv . Volunteer 21 (1 26): 18 - 23 .

1960. At t ack on t he sea lamprey - a r epo rt of progress. Mich . Conserv . 29(5): 7-9 .

PIA VIS, GEORGE W. 1961 . Emb r yological stages in the sea lam­

prey and effects of tempe r ature on d e v e lopment. U . S . Fish Wild!. Se rv., Fish . Bull. 61 : 111-143.

1962 . Exposure of several developm ent al s t ages of the sea lamprey, Petromyzon marinus, t o selective larv icide s . Copela 1962 ( 3 ): 652 - 653 .

PYCHA, RICHARD L . 1963 . Great Lakes trout program showed

progress last year . Fish Boat 8 (9 ): 32- 35 .

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ac 1 mprc y . 'opel

1959b . Eff cts of c mucus - produc Ing marinu::. . Tran::. . Am 305 - 309 .

SCH EBERGER , ED \ ARD. 1965 . Lak trout COIT eback . 'I . Con rv .

Bull. 30(1): 21 - 22 . SMITH, BER . 'ARD R ., and J.IVE.R H. . F.l. -

LIOTT . I 53 . 10vem nt of para ItlC-P~

lampreys in Lake::. Huron T r ans . Amer . Fl::.h . Soc . 2: 12~ - 12

SMITH , BER. ARD R. , nd A LlH.R YO McLAI ' .

1962 . Estimation of t h' brook and" 'c1 1.1 prey ammocete population" o f hr .. stream::. . Great Lake::. 1:"1 h . Comm . , Tech . H.ep . 4: 1_ 1><.

SMITH, MA ' ' I 'G A. ., Vl:;R 0 C. API'Lr­GA TE, and B, G . H . JOH 'SO .

1960. ColorimetriC determm;)tlOn )f h, I -genatp.d nit r ophpno\::. add.'d to "tr(' 1m as sea lamprpy larvicide::. . Anal. ( h"m . 32(12): I 70-lf75 .

19 61 . Physical properti .. ::. o f "oml' n110-nit r ophenols . J . Chem. r.ng . Datd f (I)

607 - 608 . THOMPSO i': , PAL L E .

1955 . Dracula of the Great Lak.>s . An (·r.­cas 7(3): f - q.

WIGLEY , ROL \ 0 L . 1959 . Life r l~to ry of the ::.ea lamr r 'y of C -

yuga Llr", wYork. L.~. Fisn .'lId!. Serv ., Fi::.h . Bull . 5q : iv t p . ')1 I-I I • .

:::' . : II t

t • •

Created in 1849, the Department of the Interior--a depart­ment of conservation--is concerned with the management, conservation, and development of the Nation's water, fish, wildlife, mineral, forest, and park and recreational re ­sources. It also has major responsib1l1ties for Indian and Territorial affairs.

As the Nation's principal conservation agency, the De­partment works to assure that nonrenewable resources are developed and used wisely, that park and recreational re ­sources are conserved for the future, and that renewable resources make their full contribution to the progress, pros­perity, and security of the United States--now and in the future .

C~ITED TATE DEPART:'IEXT OF TH E I ·TERIOR

FISH A X D WILDLIF E SER YICE

BUREAU OF CO !\nlERC IAL FHUERIES

'YA SH IXGTOX , D.C. 20240

OFFICI.o.L eUSINESS

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