title: Temporal Uncoupling between Energy Acquisition and Allocation to Reproduction in a Herbivorous-Detritivorous Fish.
abstract: Although considerable knowledge has been gathered regarding the role of fish in cycling and translocation of nutrients across ecosystem boundaries, little information is available on how the energy obtained from different ecosystems is temporally allocated in fish bodies. Although in theory, limitations on energy budgets promote the existence of a trade-off between energy allocated to reproduction and somatic growth, this trade-off has rarely been found under natural conditions. Combining information on RNA:DNA ratios and carbon and nitrogen stable-isotope analyses we were able to achieve novel insights into the reproductive allocation of diamond mullet (Liza alata), a catadromous, widely distributed herbivorous-detritivorous fish. Although diamond mullet were in better condition during the wet season, most reproductive allocation occurred during the dry season when resources are limited and fish have poorer body condition. We found a strong trade-off between reproductive and somatic investment. Values of δ13C from reproductive and somatic tissues were correlated, probably because δ13C in food resources between dry and wet seasons do not differ markedly. On the other hand, data for δ15N showed that gonads are more correlated to muscle, a slow turnover tissue, suggesting long term synthesis of reproductive tissues. In combination, these lines of evidence suggest that L. alata is a capital breeder which shows temporal uncoupling of resource ingestion, energy storage and later allocation to reproduction.
authors.affiliation: Australian Rivers Institute - ARI, Griffith University, Brisbane, Australia.|Coordenação de Pesquisas em Biodiversidade, Instituto Nacional de Pesquisas da Amazônia - INPA, Manaus, Brazil.|Programa Ciência Sem Fronteiras, Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq, Brasilia, Brazil.
authors.forename: Francisco
authors.initials: F
authors.lastname: Villamarín
authors.affiliation: Coordenação de Pesquisas em Biodiversidade, Instituto Nacional de Pesquisas da Amazônia - INPA, Manaus, Brazil.
authors.forename: William E
authors.initials: WE
authors.lastname: Magnusson
authors.affiliation: School of Environment and Sustainability, University of Saskatchewan, Saskatoon, Canada.
authors.forename: Timothy D
authors.initials: TD
authors.lastname: Jardine
authors.affiliation: Australian Rivers Institute - ARI, Griffith University, Brisbane, Australia.
authors.forename: Dominic
authors.initials: D
authors.lastname: Valdez
authors.affiliation: Australian Rivers Institute - ARI, Griffith University, Brisbane, Australia.
authors.forename: Ryan
authors.initials: R
authors.lastname: Woods
authors.affiliation: Australian Rivers Institute - ARI, Griffith University, Brisbane, Australia.
authors.forename: Stuart E
authors.initials: SE
authors.lastname: Bunn
mesh_terms: D050154:Adiposity; D000818:Animals; D004734:Energy Metabolism; D005260:Female; D005399:Fishes / Q000502:physiology*; D060434:Herbivory; D050356:Lipid Metabolism; D008297:Male; D012098:Reproduction