The relationship between habitat structure and fish faunas on New Zealand reefs

Quantitative characterisation of reef fish diversity among nearshore habitats in a northeastern New Zealand marine reserve

“…agreement between the global pattern displayed in both the unconstrained and constrained ordination techniques suggests that the maximum variability calculated by the unconstrained ordination was owing to the influence of habitat type. The dominant role of habitat type in determining fish community structure revealed in this study is in agreement with other published studies (Choat & Ayling 1987;Syms 1995;Syms & Jones 1999;Anderson & Millar 2004;Valesini et al 2004;Brokovich et al 2006;Feary & Clements 2006;York et al 2006;Wellenreuther et al 2007) and is in opposition to the view of Robinson & Levings (1995) who suggested that fish are too mobile to allow the detection of significant differences in their community compositions among nearshore habitats. The present study also showed that subtle differences in reef fish community compositions can be detected with depth within a singularly defined nearshore habitat type, namely kelp.…”

“…Characterisation of fish assemblages between nearshore habitats is typically assessed by comparing differences between a few extreme habitat types, for example, kelp forests versus algal turf flats/urchin barrens (Choat & Ayling 1987;Anderson & Millar 2004), or by examining a subset of species such as the Tripterygiidae (Syms 1995;Feary & Clements 2006;Wellenreuther et al 2007). Quantitative examination of entire fish assemblages between more subtly different habitat types in nearshore regions is necessary to allow changes in species abundances and/or assemblage structure within these habitats to be detected and managed effectively.…”

Distributional expansion ofCarpophyllum flexuosumonto wave‐exposed reefs in north‐eastern New Zealand

“…In January-February 1991 we measured lengths of C. flexuosum at six sites along a short gradient of wave exposure at the offshore Mokohinau Islands (Fig. 1), which have clear water influenced by the East Auckland Current (Choat & Ayling 1987), and are unlikely to be affected by gradients of salinity or sedimentation because of their small catchment and their distance from the mainland (c. 50 km). Again, stipes were measured within 1-m 2 quadrats.…”

Spatial variation of reef fishes and the relative influence of biotic and abiotic habitat traits

“…Adding to the small-scale variation, previous investigations have detected a considerable proportion of variance in the distribution of reef fishes at scales comparable to that of the present sites. This was often explained with spatial changes of hydrodynamics [95], the relative availability of algae playing different functional roles [30,84,96,97], or a combination of biotic and abiotic processes [32,98,99]. Such differences, instead, were unlikely to occur in the present system, where all sampled reefs and sites were chosen as being comparable in terms of wave exposure and general occurrence of macroalgal beds and might have critically contributed to the smaller variation at these scales compared to the transect scale.…”