Diet of subtropical herbivorous fishes in northeastern New Zealand

Abstract

Diet was examined in four species of marine herbivorous fishes in northeastern New Zealand, which for three species represents the southern end of their range. Aplodactylus etheridgii (Aplodactylidae) and Girella cyanea (Girellidae) are restricted to the subtropical southwest Pacific region, whereas Kyphosus bigibbus (Kyphosidae) is distributed antitropically in the Indian and Pacific oceans. The temperate Australasian herbivore A. arctidens was also examined for comparative purposes. Aplodactylus etheridgii and A. arctidens predominantly consumed rhodophytes (91.22% ± 4.12 SE and 72.50% ± 6.63 SE, respectively), with A. arctidens also consuming a significant proportion of chlorophytes (22.65% ± 6.91 SE), mainly Viva spp. Kyphosus bigibbus consumed predominantly phaeophytes (91.50% ± 2.69 SE), mainly Carpophyllum spp., with the remainder consisting of rhodophytes. Girella cyanea was omnivorous, consuming some animal material (12.45% ± 7.29 SE), mainly sponges and hydroids.

Keywords:

• marine
• algae
• Kyphosidae
• Girellidae
• Aplodactylidae