OLR (1987) 34 (12) E. Biological Oceanography 1069

87:6990 Lewbel, G.S., R.L. Howard and B.J. Gallaway, 1987.

Zouation of dominant fouling organisms on northern Gulf of Mexico petroleum platforms. Mar. environ. Res., 21(3):199-224.

Scraped samples were collected by divers at depths from 1-30 m. The main habitat-forming species were barnacles and pelecypods, which accounted for over 99% of the drained weight of the samples. Although the fauna of both near and offshore platforms included many cosmopolitan taxa, some tropical species more commonly found on coral reefs were collected on offshore platforms. Algal abundance was higher near the surface, especially at nearshore platforms, and higher offshore than nearshore at all depths. There was no evidence that a water discharge on one platform had any significant effect on community composition a few meters away although it was not possible to determine the chemical content of the discharge. LGL Ecol. Res. Assoc., Inc., 1410 Cavitt St., Bryan, TX 77801, USA.

El40. Birds 87:6991

Hobson, K.A., 1987. Use of stable-carlton isotope analysis to estimate marine and terrestrial protein content in gull diets. Can. J. Zool., 65(5): 1210- 1213. Dept. of Zool., Univ. of Manitoba, Winnipeg, MB R3T 2N2, Canada.

El50. Microbiology (communities, pro- cesses; also bacteria, fungi, yeasts, viruses, etc.)

87:6992 Albright, L.J. and S.K. McCrae, 1987. Annual

bacterioplankton biomasses and productivities in a temperate west coast Canadian fjord. AppL environ. Microbiol., 53(6): 1277-1285.

Results of an eighteen-month study of bacterio- and phytoplankton throughout a 250 m deep water column in Howe Sound reveal the importance of data comparison over an entire annual cycle because of the asynchronous peak and trough behavior of bacterial and primary production. Bacterial pro- duction represents 9-23% or 29-64% (depending on the bacterial C to biovolume ratio used) of the phytoplankton production in Howe Sound, on an annual basis. Dept. of Biol. Sci., Simon Fraser Univ., Burnaby, BC, V5A IS6, Canada. (gsb)

87:6993 Grant, Jonathan and U.V. Bathmann, 1987. Swept

away: resuspension of bacterial mats regulates benthic-pelagic exchange of sulfur. Science, 236(4807): 1472-1474.

Material from colorless sulfur bacteria (Beggiatoa spp.) forms extensive white sulfur mats on coastal, oceanic, and deep-sea surface sediments. These chemoautotrophic bacteria oxidize soluble reduced sulfur compounds and deposit elemental sulfur, enriching the surface sediment fivefold over deeper sediments. Laboratory flume experiments with Beg- giawa mats from an intertidal sandflat demonstrated that even slight erosion of sediment causes a flux of 160 mmol S m -2 h i, two orders of magnitude greater than the flux produced by benthic bacterial sulfate reduction or sulfide oxidation. These experiments indicate that resuspension of bacterial mats by waves and currents is a rapid mechanism by which sediment sulfur is recycled to the water column. @1987 by AAAS. Dept. of Oceanogr., Dalhousie Univ., Halifax, NS B3H 4J1, Canada.

87:6994 Kaysner, C.A., Carlos Abeyta Jr., M.M. Wekell,

Angelo DePaola Jr., R.F. Stott and J.M. Leitch, 1987. Incidence of Vibrio cholerae from estuaries of the United States west coast. Appl. environ. Microbiol., 53(6):1344-1348. Seafood Products Res. Center, Food and Drug Admin., Seattle, WA 98174, USA.

87:6995 Kaysner, C.A., Carlos Abeyta Jr., M.M. Wekell,

Angelo DePaola Jr., R.F. Stott and J.M. Leitch, 1987. Virulent strain~ of Vibrio vnlnirleUS igollted from estuaries of the United States west coast. Appl. environ. Microbiol, 53(6):1349-1351. Sea- food Products Res. Center, Food and Drug Admin., Seattle, WA 98174, USA.

87:6996 Knowles, Roger and D.R.S. Lean, 1987. Nitrifica-

tion: a significant cause of oxygen depletion under winter ice. Can. J. Fish. aquat. Sci., 44(1):743- 749.

Changes in concentrations of ammonium, nitrite, nitrate, and oxygen suggested significant nitrifica- tion throughout the water column of mesotrophic Lake St. George, Ontario, during the winter months of 1976-1984. Existence of nitrapyrin- and acety- lene-sensitive ~4C-bicarbonate incorporation con- firmed bacterial nitrification. Late January to early March nitrification occurred at an average rate of ~13/ tg N L -~ d -~. Numbers of detectable nitrifying bacteria appeared too low (by 2 to 4 orders of