Ecological Research

, Volume 24, Issue 1, pp 109–118

Effects of body size, age and maturity stage on diet in a large shark: ecological and applied implications


    • Department of BiologyDalhousie University
  • Verónica B. García
    • Department of BiologyDalhousie University
  • Roberto C. Menni
    • Departamento Científico Zoología VertebradosMuseo de La Plata
    • Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)
  • Alicia H. Escalante
    • Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)
    • Departamento de BiologíaUniversidad Nacional de Mar del Plata
  • Natalia M. Hozbor
    • Instituto Nacional de Investigación y Desarrollo Pesquero
Original Article

DOI: 10.1007/s11284-008-0487-z

Cite this article as:
Lucifora, L.O., García, V.B., Menni, R.C. et al. Ecol Res (2009) 24: 109. doi:10.1007/s11284-008-0487-z


Ontogenetic diet shifts are a widespread phenomenon among vertebrates, although their relationships with life history traits are poorly known. We analyzed the relative importance of body size, age and maturity stage as determinants of the diet of a marine top predator, the copper shark, Carcharhinus brachyurus, by examining stomach contents using a multiple-hypothesis modeling approach. Copper sharks shifted their diet as size and age increased and as they became sexually mature, incorporated larger prey as they grew, and had a discrete shift in diet with body size, with only individuals larger than ≈200 cm total length able to prey on chondrichthyans. Body size was the most important trait explaining the consumption of chondrichthyans, while age determined the consumption of pelagic teleosts. Pelagic teleosts were consumed mostly by medium-aged sharks, a result, probably, of a risk-reducing feeding strategy at young ages coupled with either a senescence-related decline in performance or a change in sensory capabilities as sharks age. Copper sharks of all sizes were able to cut prey in pieces, implying that gape limitation (i.e., the impossibility of eating prey larger than a predator’s mouth) did not play a role in producing the diet shift. Our results suggest that, contrary to the current practice of setting minimum but not maximum size limits in catches, any plan to conserve or restore the ecological function of sharks, through their predatory control of large prey, should aim to maintain the largest individuals.


PredationOntogenetic niche shiftLife historyShark fisheriesPatagonia

Copyright information

© The Ecological Society of Japan 2008