Spatial and temporal changes in assemblage structure of zooplankton and pelagic fish in the eastern Bering Sea across varying climate conditions

Zooplankton and pelagic fish samples collected on the eastern Bering Sea shelf in late summer 2003-2010 were used to evaluate spatial and temporal changes in the plankton and nekton community structure. The zooplankton were sampled by vertical towing of a Juday net (168 μm mesh) and oblique towing of a Bongo net (505 μm mesh), and pelagic fish were caught by midwater rope trawl. The communities were compared across climate regimes (in relatively warm and cold years), by latitude (in the northern and southern parts of the shelf), and by water depth (in the inner, middle, and outer domains of the shelf). Zooplankton were dominated by the small copepod Oithona spp. in warm years but relatively larger copepods Pseudocalanus spp. and Acartia spp. in cold years. Notably, the large copepod Calanus spp., an important energy-rich prey for fish, were more abundant in cold years than warm years. Age-0 walleye pollock Gadus chalcogrammus were more abundant in warm years, while capelin Mallotus villosus were abundant within cold-year communities over the northern shelf. Latitudinal variations in communities were more prominent in the cold years, particularly in 2007 and 2010. Cross-shelf variations were evident, particularly for large zooplankton and fish, with communities corresponding to specific oceanographic domains. Outer shelf communities varied less than inner and middle shelf communities between warm and cold periods, suggesting that this region may be less impacted by climate variability. An understanding of the overlap of zooplankton (prey) and fish communities within specific shelf regions or climate regimes may provide information for ecosystem-based approaches to fisheries management.

eastern Bering Sea, zooplankton, pelagic fish, climate change, community structure, water temperature

1. Andrews A.G. III, Strasburger W.W., Farley E.V. Jr. et al. Effects of warm and cold climate conditions on capelin (Mallotus villosus) and Pacific herring (Clupea pallasii) in the eastern Bering Sea // Deep-Sea Res. II (in press).

2. Baier C.T. and Napp J.M. Climate-induced variability in Calanus marshallae populations // J. Plankton Res. - 2003. - Vol. 25. - P. 771-782.

3. Brander K.M., Blom G., Borges M.F. et al. Changes in fish distribution in the eastern North Atlantic: are we seeing a coherent response to changing temperature? // ICES Mar. Sci. Symp. - 2003. - Vol. 219. - P. 260-273.

4. Clarke K.R. and Gorley R.N. PRIMER v6: user manual/tutorial. - Plymouth : PRIMER-E, 2006.

5. Clarke K.R. and Warwick R.M. Change in marine communities: an approach to statistical analysis and interpretation. 2nd ed. - Plymouth : PRIMER-E, 2001.

6. Coachman L.K. Circulation, water masses, and fluxes on the southeastern Bering Sea shelf // Cont. Shelf Res. - 1986. - Vol. 5(1-2). - P. 23-108.

7. Coyle K., Eisner L., Mueter F. et al. Climate change in the southeastern Bering Sea: impacts on pollock stocks and implications for the Oscillating Control Hypothesis // Fish. Oceanogr. - 2011. - Vol. 20(2). - P. 139-156.

8. Coyle K.O. and Pinchuk A.I. Climate-related differences in zooplankton density and growth on the inner shelf of the southeastern Bering Sea // Prog. Oceanogr. - 2002. - Vol. 55. - P. 177-194.

9. Coyle K.O., Pinchuk A.I., Eisner L.B. and Napp J.M. Zooplankton species composition, abundance and biomass on the eastern Bering Sea shelf during summer: the potential role of water column stability and nutrients in structuring the zooplankton community // Deep-Sea Res. II. - 2008. - Vol. 55. - P. 1775-1791.

10. Danielson S., Eisner L., Weingartner T. and Aagaard K. Thermal and haline variability over the central Bering Sea shelf: Seasonal and interannual perspectives // Cont. Shelf Res. - 2011. - doi:10.1016/ j.csr.2010.12.010.

11. Danielson S., Weingartner T., Aagaard K. et al. Circulation on the central Bering Sea shelf, July 2008 to July 2010 // J. Geophys. Res. - 2012. - Vol. 117. - C10003, doi:10.1029/2012JC008303.

12. Duffy-Anderson J.T., Busby M.S., Mier K.L. et al. Spatial and temporal patterns in summer ichthyoplankton assemblages on the eastern Bering Sea shelf 1996-2000 // Fish. Oceanogr. - 2006. - Vol. 15. - P. 80-94.

13. Eisner L., Napp J., Mier K. et al. Climate-mediated changes in zooplankton community structure for the eastern Bering Sea // Deep-Sea Res. II. - 2014. - doi: 10.1016/j.dsr2.2014.03.004.

14. Farley E., Murphy J., Adkison M. and Eisner L. Juvenile sockeye salmon distribution, size, condition and diet during years with warm and cool spring sea temperatures along the eastern Bering Sea shelf // J. Fish Biol. - 2007. - Vol. 71(4). - P. 1145-1158.

15. Farley E.V. and Moss J.H. Growth rate potential of juvenile chum salmon on the eastern Bering Sea shelf: an assessment of salmon carrying capacity // North Pacific Anadr. Fish Comm. Bull. - 2009. - Vol. 5. - P. 265-277.

16. Farley E.V., Heintz R.A., Andrews A.G. and Hurst T.P. Size, diet, and condition of age-0 Pacific Cod (Gadus macrocephalus) during warm and cool climate states in the eastern Bering Sea // Deep-Sea Res. II. - 2014. - doi:10.1016/j.dsr2.2014.12.011.

17. Farley E.V. Jr., Murphy J.M., Wing B.W. et al. Distribution, migration pathways, and size of western Alaska juvenile salmon along the eastern Bering Sea shelf // Alsk. Fish. Res. Bull. - 2005. - Vol. 11(1). - P. 15-26.

18. Gibson G.A., Coyle K.O., Hedstrom K. and Curchitser E.N. A modeling study to explore on-shelf transport of oceanic zooplankton in the Eastern Bering Sea // J. Mar. Sys. - 2013. - Vol. 121. - P. 47-64.

19. Habicht C., Seeb L.W., Myers K.W. et al. Summer-fall distributions of stocks of immature sockeye salmon in the Bering Sea as revealed by single-nucleotide polymorphisms // Trans. Am. Fish. Soc. - 2010. - Vol. 139(4). - P. 1171-1191.

20. Heintz R.A., Siddon E.C., Farley E.V. Jr. and Napp J.M. Correlation between recruitment and fall condition of age-0 walleye pollock (Theragra chalcogramma) from the eastern Bering Sea under varying climate conditions // Deep-Sea Res. II. - 2013. - Vol. 94. - P. 150-156.

21. Hollowed A.B., Barbeaux S.J., Cokelet E.D. et al. Effects of climate variations on pelagic ocean habitats and their role in structuring forage fish distributions in the Bering Sea // Deep-Sea Res. II. - 2012. - Vol. 65-70. - P. 230-250.

22. Hunsicker M., Ciannelli L., Bailey K.M. et al. Functional responses and scaling in predator-prey interactions of marine fishes: contemporary issues and emerging concepts // Ecol. Lett. - 2011. - doi: 10.1111/j.1461-0248.2011.01696.x.

23. Hunt G.L. Jr. and Stabeno P.J. Climate change and the control of energy flow in the southeastern Bering Sea // Prog. Oceanogr. - 2002. - Vol. 55. - P. 5-22.

24. Hunt G.L. Jr., Coyle K.O., Eisner L. et al. Climate impacts on eastern Bering Sea foodwebs: A synthesis of new data and an assessment of the Oscillating Control Hypothesis // ICES J. Mar. Sci. - 2011. - doi:10.1093/icesjms/fsr036.

25. Hunt G.L. Jr., Stabeno P.J., Walters G. et al. Climate change and control of the southeastern Bering Sea pelagic ecosystem // Deep-Sea Res. II. - 2002. - Vol. 49. - P. 5821-5853.

26. Ianelli J.N., Hollowed A.B., Haynie A.C. et al. Evaluating management strategies for eastern Bering Sea walleye pollock (Theragra chalcogramma) in a changing environment // ICES J. Mar. Sci. - 2011. - Vol. 68(6). - P. 1297-1304.

27. Iverson R.L., Coachman L.K., Cooney R.T. et al. Ecological significance of fronts in the southeastern Bering Sea // Ecological Processes in Coastal and Marine Systems. - N.Y. : Plenum Press, 1979. - P. 437-466.

28. Levin P.S., Fogarty M.J., Murawski S.A. and Fluharty D. Integrated ecosystem assessments: developing the scientific basis for ecosystem-based management of the ocean // PLoS Biol. - 2009. - Vol. 7(1), e1000014. doi:10.1371/journal.pbio.1000014.

29. Link J., Bundy A., Overholtz W.J. et al. Ecosystem-based fisheries management in the Northwest Atlantic // Fish and Fish. - 2011. - Vol. 12. - P. 152-170.

30. Moss J.H., Farley E.V., Feldman A.M. and Ianelli J.N. Spatial distribution, energetic status, and food habits of eastern Bering Sea age-0 walleye pollock // Trans. Am. Fish. Soc. - 2009. - Vol. 138. - P. 497-505.

31. Mueter F.J. and Litzow M.A. Sea ice retreat alters the biogeography of the Bering Sea continental shelf // Ecol. Appl. - 2008. - Vol. 18(2). - P. 309-320.

32. Mueter F.J., Hunt G.L. Jr. and Litzow M.A. The Eastern Bering Sea shelf: a highly productive seasonally ice-covered sea // ICES CM2007/D:04. - 2007. - P. 1-10.

33. Mueter F.J., Ladd C., Palmer M.C. and Norcross B.L. Bottom-up and top-down controls of walleye pollock (Theragra chalcogramma) on the Eastern Bering Sea shelf // Prog. Oceanogr. - 2006. - Vol. 68. - P. 152-183.

34. Mueter F.J., Siddon E.C. and Hunt G.L. Jr. Climate change brings uncertain future for subarctic marine ecosystems and fisheries // North by 2020: Perspectives on Alaska’s Changing Social-Ecological Systems. - Fairbanks : Univ. of Alaska Press, AK, 2011. - P. 329-357.

35. Overland J.E. and Stabeno P.J. Is the climate of the Bering Sea warming and affecting the ecosystem? // EOS Trans. Am. Geophys. Union. - 2004. - Vol. 85(33). - P. 309-312.

36. Parker-Stetter S.L., Horne J.K., Farley E.V. et al. Summer distributions of forage fish in the eastern Bering Sea // Deep-Sea Res. II. - 2013. - Vol. 94. - P. 211-230.

37. Perry A.L., Low P.J., Ellis J.R. and Reynolds J.D. Climate change and distribution shifts in marine fishes // Science. - 2005. - Vol. 308. - P. 1912-1915.

38. Ressler P.H., De Robertis A., Warren J.D. et al. Developing an acoustic survey of euphausiids to understand trophic interactions in the Bering Sea ecosystem // Deep-Sea Res. II. - 2012. - Vol. 65-70. - P. 184-195.

39. Rose G.A. Capelin (Mallotus villosus) distribution and climate: a sea «canary» for marine ecosystem change // Ices J. Mar. Sci. - 2005. - Vol. 62. - P. 1524-1530.

40. Siddon E.C., Duffy-Anderson J.T. and Mueter F.J. Community-level response of larval fish to environmental variability in the southeastern Bering Sea // Mar. Ecol. Prog. Ser. - 2011. - Vol. 426. - P. 225-239.

41. Siddon E.C., Kristiansen T., Mueter F.J. et al. Spatial match-mismatch between juvenile fish and prey explains recruitment variability across contrasting climate conditions in the eastern Bering Sea // PLoS ONE. - 2013. - Vol. 8(12), e84526. doi:10.1371/journal.pone.0084526.

42. Sigler M.F., Stabeno P.J., Eisner L.B. et al. Spring and fall phytoplankton blooms in a productive subarctic ecosystem, the eastern Bering Sea, during 1995-2011 // Deep-Sea Res. II. - 2013. - doi: 10.1016/j.dsr2.2013.12.007.

43. Spencer P.D. Density-independent and density-dependent factors affecting temporal changes in spatial distributions of eastern Bering Sea flatfish // Fish. Oceanogr. - 2008. - Vol. 17. - P. 396-410.

44. Stabeno P., Napp J., Mordy C. and Whitledge T. Factors influencing physical structure and lower trophic levels of the eastern Bering Sea shelf in 2005: Sea ice, tides and winds // Prog. Oceanogr. - 2010. - Vol. 85. - P. 180-196.

45. Stabeno P.J., Farley E.V., Kachel N.B. et al. A comparison of the physics of the northern and southern shelves of the eastern Bering Sea and some implications for the ecosystem // Deep-Sea Res. II. - 2012a. - Vol. 65-70. - P. 14-30.

46. Stabeno P.J., Kachel N.B., Moore S.E. et al. Comparison of warm and cold years on the southeastern Bering Sea shelf and some implications for the ecosystem // Deep-Sea Res. II. - 2012b. - Vol. 65-70. - P. 31-45.

47. Urawa S., Sato S., Crane P.A. et al. Stock-specific ocean distribution and migration of chum salmon in the Bering Sea and north Pacific Ocean // North Pacific Anadr. Fish Comm. Bull. - 2009. - Vol. 5. - P. 131-146.

48. Volkov A.F. Recommendations for Expedited Zooplankton Sample Processing at Sea. - Vladivostok : TINRO, 1984. - 31 p (in Rus.).

49. Volkov A.F. The Results of Zooplankton Studies in the Bering Sea under the NPAFC Program (BASIS Expedition). Part 1. Eastern Areas // Russian J. Mar. Biol. - 2012. - Vol. 38(7). - P. 474-494.

50. Volkov A.F., Efimkin A.Y. and Kuznetsova N.A. Characteristics of the plankton community of the Bering Sea and several regions of the North Pacific in 2002-2006 // Izv. TINRO. - 2007. - Vol. 151. - P. 338-364 (in Rus.).

51. Walsh J.J. and McRoy C.P. Ecosystem analysis in the southeastern Bering Sea // Cont. Shelf Res. - 1986. - Vol. 5. - P. 259-288.