New publication
McSweeney, D.J., R.W. Baird, and S.D. Mahaffy. 2007. Site
fidelity, associations and movements of Cuvier’s (Ziphius cavirostris) and
Blainville’s (Mesoplodon densirostris) beaked whales off the island of Hawai‘i.
Marine Mammal Science 23: doi:10.1111/j.1748-7692.2007.00135.x
ABSTRACT
Although the Ziphiidae are the second-most speciose family of
cetaceans, information on beaked whale species and populations has been limited
by the difficulties in finding and approaching free-ranging individuals. Site
fidelity, patterns of association and movements of two species, Cuvier’s
(Ziphius cavirostris) and Blainville’s (Mesoplodon densirostris) beaked whales,
were assessed using a 21-year photographic dataset from the west coast of the
island of Hawai‘i. Re-sightings of individuals of both species spanned 15-years,
suggesting long-term site fidelity to the area. Long-term re-sightings were
documented primarily from adult females of both species. Group sizes for both
species were small and most groups had only a single adult male present. For
Blainville’s beaked whales, repeated associations between adult females and
adult males were documented for all re-sightings of adult males over periods
from 1-154 days. Among adult females, while repeated associations occurred up to
9 years apart, individuals were seen separately in intervening years.
Individuals of both species seen on multiple occasions were typically documented
in multiple months/seasons, suggesting they may use the study area throughout
the year. Such long-term site-fidelity has implications both for potential
population structure and for susceptibility of beaked whale populations to
anthropogenic impacts.