Biology of the New Zealand carpet shark Cephaloscyllium isabellum (Scyliorhinidae)

Abstract

The carpet shark Cephaloscyllium isabellum is abundant and widespread around the New Zealand coastal shelf from the tidal zone to about 500 m. Their overall depth distribution deepens with decreasing latitude, indicating a distribution moderated by water temperature. Cephaloscyllium isabellum is a generalist benthic carnivore and scavenger that uses both ambush and active searching hunting strategies. It has a broad diet (mainly fish, crustaceans, cephalopods, gastropods, and holothurians) and an apparent ability to manipulate prey to remove the shells of gastropods and pagurids before ingesting these animals. Length at maturity is about 60 cm for male and 76 cm for female C. isabellum. They may have an egg-laying peak around summer but probably reproduce throughout the year; the egg laying process is described. Females attain a larger size (c. 92 cm) than males (c. 80 cm). Growth and mortality rates are unknown, and constitute the main knowledge gap for C. isabellum and for Cephaloscyllium species in general.