I am pleased to announce the publication of the following
paper on habitat use in Blainville's beaked whale:
MacLeod, C.D. and Zuur, A.F. 2005. Habitat utilization by Blainvilles
beaked whales off Great Abaco, northern Bahamas, in relation to seabed
topography. Marine Biology. DOI: 10.1007/s00227-004-1546-9
We investigated habitat utilization in Blainvilles beaked whale,
Mesoplodon densirostris, in the northern Bahamas and, as such, this is the first
analysis of fine-scale habitat utilization of any member of the genus
Mesoplodon. We divided the area into 500×500 m grid squares and each square was
assigned a classification for presence or absence of Blainvilles beaked whales,
along with details of water depth, seabed gradient and seabed aspect. All
squares where Blainvilles beaked whales occurred had gradients from 68 to 296
m/km and depths from 136 to 1,319 m and most faced northeast compared with 0–526
m/km, 10–3,000 m and all aspects for the whole study area. Generalized additive
models and classification trees indicated that, in order of importance, aspect,
gradient and depth were related to occurrence of Blainvilles beaked whales
within the study area. We hypothesize that the relationships between habitat
utilization and these topographic variables relates to the effects of
interactions between a deepwater current and the seabed topography on preferred
prey. Locally, prey animals may be concentrated in areas with a northeast
aspect, intermediate gradients and depths between 200 and 1,000 m where the Deep
Western Boundary Current is forced towards the surface by the local topography.
These are the areas where Blainvilles beaked whales preferentially
occurred.
The full article is currently available online at the following
address:
http://www.springerlink.com/index/10.1007/s00227-004-1546-9
PDFs will be available in the near future from Colin MacLeod (email:
[log in to unmask])
All the best,
Colin