Abstract
The epibenthic megafauna of the continental slope and abyssal plain of the northern Gulf of Mexico have been investigated using multi-shot bottom photography. A total of 10,388 photographs were analyzed from 100 sites encompassing a total area of 26,691 m². A total of 17,367 individual representatives of the epibenthic megafauna were observed constituting a total density of 6,507 individuals/hectare. However, dense patches of the small holothuroid Peniagone sp., representing 11,156 individuals, were observed in only one time period and only at mid-slope depths on the central transect. Excluding these organisms from the analysis, the mean density for the remaining megafauna was 2,327 individuals/hectare. Linear regression analyses failed to support significant relationships with depth. Analysis of variance was used to compare densities within and between different photographic methods, different topographic regimes and sediment types. Canyon and non-canyon sites shared many taxa and maintained similar megafaunal densities. Basin and non-basin sites, while maintaining similar densities, were comprised of different taxa. The occurrence of epibenthic megafauna in the Gulf of Mexico is significantly lower - up to two orders of magnitude - than what is observed at higher latitudes across equivalent depth intervals.
Ziegler, Matthew Peek (2002). The epibenthic megafauna of the northern Gulf of Mexico continental slope. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -2002 -THESIS -Z49.