Record Details
Field | Value |
---|---|
Title | Diet variability of forage fishes in the Northern California Current System |
Names |
Hill, Andrew D.
(creator) Daly, Elizabeth A. (creator) Brodeur, Richard D. (creator) |
Date Issued | 2015-06 (iso8601) |
Note | To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/journal-of-marine-systems/. |
Abstract | As fisheries management shifts to an ecosystem-based approach, understanding energy pathways and trophic relationships in the Northern California Current (NCC) will become increasingly important for predictive modeling and understanding ecosystem response to changing ocean conditions. In the NCC, pelagic forage fishes are a critical link between seasonal and interannual variation in primary production and upper trophic groups. We compared diets among dominant forage fish (sardines, anchovies, herring, and smelts) in the NCC collected in May and June of 2011 and June 2012, and found high diet variability between and within species on seasonal and annual time scales, and also on decadal scales when compared to results of past studies conducted in the early 2000s. Copepoda were a large proportion by weight of several forage fish diets in 2011 and 2012, which differed from a preponderance of Euphausiidae found in previous studies, even though all years exhibited cool ocean conditions. We also examined diet overlap among these species and with co-occurring subyearling Chinook salmon and found that surf smelt diets overlapped more with subyearling Chinook diets than any other forage fish. Herring and sardine diets overlapped the most with each other in our interdecadal comparisons and some prey items were common to all forage fish diets. Forage fish that show plasticity in diet may be more adapted to ocean conditions of low productivity or anomalous prey fields. These findings highlight the variable and not well-understood connections between ocean conditions and energy pathways within the NCC. |
Genre | Article |
Topic | Pelagic nekton |
Identifier | Hill, A. D., Daly, E. A., & Brodeur, R. D. (2015). Diet variability of forage fishes in the Northern California Current System. Journal of Marine Systems, 146, 121-130. doi:10.1016/j.jmarsys.2014.08.006 |