Bathymetric distributions of notothenioid fishes

Abstract

There has been no comprehensive study of the bathymetry of notothenioid fishes. Therefore, I analyzed minimum and maximum depths and depth ranges for 128 of 142 species that collectively range from 0 to ≈3000 m. Means (and medians) for maximum depths are 176 m (75 m) for non-Antarctic, 511 m (360 m) for sub-Antarctic, and 963 m (899 m) for Antarctic species; medians are significantly different. Means (and medians) for depth ranges for the three groups are 140 (55 m), 470 (345 m), and 727 m (714 m), respectively, with significantly different medians. The mean maximum depths for the Cryonotothenioidea are: Nototheniidae—525 m, Harpagiferidae—88 m, Artedidraconidae—906 m, Bathydraconidae—1165 m, and Channichthyidae—910 m. If five species of Bathydraco, with a mean of 2098 m are excluded, the mean for the Bathydraconidae is 741 m. With the exceptions of the harpagiferids and Bathydraco, there is overlap of the 95% confidence intervals for the means of other families. Thirteen Antarctic and sub-Antarctic species with maximum depths and/or depth ranges ≥1500 m are especially deep-living: four nototheniids, four species of Bathydraco, three species of Pogonophryne, and two channichthyids. The most common depth range is 0–50 m for non-Antarctic, 200–400 m for sub-Antarctic and 600–800 m for Antarctic species. Three species have depth ranges >2000 m. Species diversity peaks at 50 m for non-Antarctic, 100 m for sub-Antarctic, and 500 m for Antarctic species. Notothenioids are not eurybathic compared with older deep-sea taxa but are eurybathic relative to marine percomorphs.