TY - JOUR
T1 - Variation in foraging behavior facilitates resource partitioning in a polymorphic cichlid, Herichthys minckleyi
AU - Swanson, Brook O.
AU - Gibb, Alice C.
AU - Marks, Jane C.
AU - Hendrickson, Dean A.
N1 - Funding Information:
Acknowledgements We thank S. Skúlason and B. Kristjánsson for suggesting several of the analyses used here. F. García de León helped us obtain permits required to carry out our research (Secretaría de Agricultura, Ganadería, Desarrollo Rural, Pesca y Alimentación, Comisión Nacional de Acuacul-tura y Pesca, Dirección General de Ordenamiento Pesquero y Acuícola: 180202-613-03-050 and amendments, 041099-213-03 and 140102-613-03). K. Cummins, H. Kloeppel, C. Williamson, M. Hess, and A. Cohen assisted with our field studies. E. Dinger and H. Kloppel provided invertebrate abundance data and W.L. Montgomery provided equipment. D. Bolnick provided the program that determined levels of individual specialization and assisted with its use. L. Ferry-Graham and L. Drickamer provided helpful comments on early drafts of the manuscript. A NAU intramural grant and NSF IBN 0002301 to ACG, EPA Star Fellowship U-91591901 to BOS, and an Ecosystem Research Program grant from The Nature Conservancy to JCM and DAH, and NSF EB 0074876 POWRE to JCM supported this work.
PY - 2008/10
Y1 - 2008/10
N2 - We examined foraging behavior (microhabitat use and feeding behavior) in a trophically polymorphic cichlid fish, Herichthys minckleyi, to address several questions regarding resource partitioning in this threatened species. These include: (1) do morphotypes demonstrate different foraging behaviors? (2) do individuals within a morphotype vary in their foraging behavior (e.g. are some individuals specialists, only using a subset of available resources, while other are generalists)? (3) do foraging behaviors vary between isolated pools? (4) do foraging behaviors vary across seasons? We quantified microhabitat use and feeding behavior for over 100 individuals (of two morphotypes) feeding freely in two isolated pools (populations) and across two seasons (winter and summer). We found differences in foraging behavior between morphotypes and individual specializations within morphotypes; i.e. some individuals specialize on certain food resources by using a few feeding behaviors within a subset of microhabitats, whereas others employ a range feeding behaviors across many microhabitats. Foraging behavior also varied between pools and across seasons. This spatial and temporal variation in foraging behavior and resource use may serve to maintain this polymorphism, as the relative fitness of the each morph may vary over space and time.
AB - We examined foraging behavior (microhabitat use and feeding behavior) in a trophically polymorphic cichlid fish, Herichthys minckleyi, to address several questions regarding resource partitioning in this threatened species. These include: (1) do morphotypes demonstrate different foraging behaviors? (2) do individuals within a morphotype vary in their foraging behavior (e.g. are some individuals specialists, only using a subset of available resources, while other are generalists)? (3) do foraging behaviors vary between isolated pools? (4) do foraging behaviors vary across seasons? We quantified microhabitat use and feeding behavior for over 100 individuals (of two morphotypes) feeding freely in two isolated pools (populations) and across two seasons (winter and summer). We found differences in foraging behavior between morphotypes and individual specializations within morphotypes; i.e. some individuals specialize on certain food resources by using a few feeding behaviors within a subset of microhabitats, whereas others employ a range feeding behaviors across many microhabitats. Foraging behavior also varied between pools and across seasons. This spatial and temporal variation in foraging behavior and resource use may serve to maintain this polymorphism, as the relative fitness of the each morph may vary over space and time.
KW - Feeding ecology
KW - Individual specialization
KW - Intra-specific variation
KW - Trophic polymorphism
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U2 - 10.1007/s10641-007-9307-5
DO - 10.1007/s10641-007-9307-5
M3 - Article
AN - SCOPUS:56749132439
SN - 0378-1909
VL - 83
SP - 147
EP - 154
JO - Environmental Biology of Fishes
JF - Environmental Biology of Fishes
IS - 2
ER -