Patterns of abundance and population size structure of herbivorous fishes at the subtropical Kermadec Islands and in mainland New Zealand

Abstract

Patterns of abundance and population size structure for nominally herbivorous fishes were investigated at the subtropical Kermadec Islands in 1992 using both tape transect and timed-count techniques. Timed counts were subsequently used to sample six localities in mainland New Zealand, including coastal offshore islands. Herbivorous fishes of all genera were most abundant in shallow water. Kermadec Islands had slightly greater species richness of herbivorous fishes than north-eastern mainland New Zealand and abundances in timedtransects also showed a clear decline from north to south, with the southern localities having extremely low abundances. Offshore island groups in northeastern New Zealand had assemblages that were dominated by one pomacentrid, and size-frequency distributions that were dominated by one adult size class of that species, whereas size-frequency distributions at mainland New Zealand and Kermadec Islands locations were platykurtic. At Leigh, herbivorous fishes were observed throughout the depth range sampled (0-15 m) but were much more common in shallow macroalgal-dominated habitats. There were suggestive patterns of increasing size and decreasing abundance with increasing latitudes.

Benthic community structure and water column characteristics at two sites in the Kermadec Islands Marine Reserve, New Zealand

“…For the Kermadec group, McKnight (1968), Marshall (1979Marshall ( , 1981, Foster (1981), Nelson & Adams (1984), Schiel et al (1986), Francis et al (1987), Creese et al (1990), Cole et al (1992), Francis (1993), Brook (1998Brook ( , 1999, and Cole (2001) have all provided either species lists or descriptions of new species, or have described various aspects of the ecology of macroalgae, echinoderms, molluscs, cirripedes, scleractinian corals, and fish. However, work on subtidal benthic community structure is limited to only three studies.…”

Biogeographical and cross-shelf patterns of reef fish assemblages in a transition zone

“…Consequently, inshore habitats are also more temperate in the SIMP, with reef habitats generally dominated by macroalgae (Harriott et al 1994). Many of the temperate species that were recorded exclusively from inshore were from families that are known to strongly associate with kelps and other seaweed (Kuiter 2000;Cole 2001).…”

“…Again, this may relate to the overlap of currents and extensive reef area by providing suitable conditions for concentrations of zooplankton and phytoplankton (Fowler et al 2006), plus diverse and abundant reef invertebrates . The large schools of roving herbivorous/detritivorous fishes that graze further north on the Great Barrier Reef (GBR) (Choat et al 2004) are lacking in the SIMP, reflecting latitudinal differences in herbivorous fishes between tropical, subtropical and temperate areas (Meekan and Choat 1997;Cole 2001;Ferreira et al 2004). …”

Diet of subtropical herbivorous fishes in northeastern New Zealand

“…Second, demographic and life history parameters are important to determine whether populations are selfrecruiting on the one hand or are supplied by periodic larval immigration of long-lived species on the other. Aplodactylus etheridgii and G. cyanea occur in the southwest Pacific including Lord Howe, Norfolk and Kermadec islands, with the latter species also occurring on the mainland coast of Australia (Francis & Evans 1992;Francis 1993Francis , 1996Cole 2001). Since collections for this study began, the species K. bigibbus has been revised and divided into three species (Sakai & Nakabo 2004), only one of which (the true K. bigibbus) is recorded from New Zealand (Randall 2005).…”