Do benthivory and piscivory result in similar growth in walleye?

• Published in: Journal of fish biology Vol. 69; no. 5; pp. 1317 - 1329
• Main Authors: Paradis, Y., Bertolo, A., Perot, A., Débas, S., Magnan, P.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.11.2006; Blackwell
• Subjects: Agnatha. Pisces; backcalculation; Biological and medical sciences; feeding flexibility; foraging behaviour; Fundamental and applied biological sciences. Psychology; growth models; linear mixed model; Marine; Sander vitreus; Vertebrates: general zoology, morphology, phylogeny, systematics, cytogenetics, geographical distribution; Growth; Biology; growth models; Foraging behavior; feeding flexibility; Feeding; Vertebrata; Pisces; Sander vitreus; foraging behaviour; Models; linear mixed model; backcalculation
• ISSN: 0022-1112; 1095-8649
• DOI: 10.1111/j.1095-8649.2006.01187.x

Growth and condition of piscivorous and non‐piscivorous walleye Sander vitreus classified on the basis of their stomach contents were compared to assess the consequences of their trophic flexibility. Piscivorous males showed a significantly higher growth trajectory than non‐piscivorous ones, while there was no difference in the growth of females. No differences were found in the condition of piscivorous and non‐piscivorous walleye for either sex. Trophic specialization of males, with some individuals foraging mainly on invertebrates and others including forage fishes in their diets, seems to be the most plausible explanation for the observed growth differences. The results also suggest that invertebrates are an important component in walleye diet throughout its ontogeny.