[MARMAM] New Publication On Prey Preferences In Toothed Whales

nhy038 at abdn.ac.uk nhy038 at abdn.ac.uk
Sun Nov 19 13:22:27 PST 2006


Dear Marmammers,

The following paper on prey preferences in toothed whales has recently
been published in Marine Ecology Progress Series.  If you would be
interested in a PDF, please email c.d.macleod at abdn.ac.uk.

All the best,

Colin

MacLeod, C.D., Santos, M.B., Lopez, A and Pierce, G.J. 2006.  Relative
prey size consumption in toothed whales: implications for prey selection
and level of specialisation.  Marine Ecology Progress Series, 326: 295-307


We investigated whether toothed whales consume prey in relation to their
availability in the local environment based on the fact that availability
of potential prey is likely to decrease exponentially with increasing
size, reflecting the usual size–abundance relationships found in marine
communities. We calculated relative prey size frequency spectra for 13
species of toothed whale from the northeast Atlantic. These differed
considerably from an exponential distribution, suggesting that toothed
whales preferentially consume larger, less abundant organisms over
smaller, more abundant ones. The prey size spectra of the various cetacean
species could be separated into 3 distinct groups based on the strength of
the mode, maximum value and inter-quartile range. Group 1 species, such as
the common dolphin, consume a wide range of relatively large organisms. In
contrast, Group 2 and 3 species, such as the northern bottlenose whale and
the sperm whale respectively, specialise on narrow ranges of relatively
small organisms. We hypothesise that these differences are related to the
mode of prey capture. Group 1 species can capture prey using pincer-like
movement of jaws containing a large number of small, homodont teeth, as
well as suction-feeding, allowing them to be relatively generalist in
terms of relative prey size. In contrast, Group 2 and 3 species have a
greatly
reduced dentition and specialise on using suction to capture prey. The
morphological adaptations that make suction-feeding more efficient
restrict the size of prey that can be ingested, so that suctionfeeders are
limited to relatively small prey.

=================================================================
Dr. Colin D. MacLeod,
Teaching/Research Fellow,
School of Biological Sciences (Zoology),
University of Aberdeen,
Tillydrone Avenue,
Aberdeen,
AB24 2TZ,
UK

Email: c.d.macleod at abdn.ac.uk

In order to save paper, please do not print this email unless it is
essential.
=================================================================






More information about the MARMAM mailing list