Risky business for a juvenile marine predator? Testing the influence of foraging strategies on size and growth rate under natural conditions.
Proc Biol Sci
; 284(1852)2017 Apr 12.
Article
em En
| MEDLINE
| ID: mdl-28381626
ABSTRACT
Mechanisms driving selection of body size and growth rate in wild marine vertebrates are poorly understood, thus limiting knowledge of their fitness costs at ecological, physiological and genetic scales. Here, we indirectly tested whether selection for size-related traits of juvenile sharks that inhabit a nursery hosting two dichotomous habitats, protected mangroves (low predation risk) and exposed seagrass beds (high predation risk), is influenced by their foraging behaviour. Juvenile sharks displayed a continuum of foraging strategies between mangrove and seagrass areas, with some individuals preferentially feeding in one habitat over another. Foraging habitat was correlated with growth rate, whereby slower growing, smaller individuals fed predominantly in sheltered mangroves, whereas larger, faster growing animals fed over exposed seagrass. Concomitantly, tracked juveniles undertook variable movement behaviours across both the low and high predation risk habitat. These data provide supporting evidence for the hypothesis that directional selection favouring smaller size and slower growth rate, both heritable traits in this shark population, may be driven by variability in foraging behaviour and predation risk. Such evolutionary pathways may be critical to adaptation within predator-driven marine ecosystems.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Comportamento Apetitivo
/
Comportamento Predatório
/
Tubarões
Tipo de estudo:
Etiology_studies
/
Risk_factors_studies
Limite:
Animals
Idioma:
En
Revista:
Proc Biol Sci
Assunto da revista:
BIOLOGIA
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Canadá