Dear colleagues,
We are pleased to announce the
following recent publication in Marine Mammal Science.
Rasmussen, K., Calambokidis,
J. and Steiger, G. H. 2011. Distribution and migratory destinations of humpback
whales off the Pacific coast of Central America during the boreal winters of
1996–2003. Marine Mammal Science.
doi: 10.1111/j.1748-7692.2011.00529.x
Abstract
Here, we examine the
distribution, habitat use, and migratory destinations of North Pacific humpback
whales wintering off Central America. Coastal boat surveys were conducted off
Costa Rica and Panama between 1996 and 2003. In 1999, a broader survey was
conducted along most of Central America. Over 23,000
km were surveyed, with
the greatest effort off southern Costa Rica. We made 191 sightings of 320
individual humpback whales. Whales were seen between 14◦N and 8◦N, making this
the most southerly of the North Pacific wintering areas. Encounters included
singles, adult pairs, singers, and mother/calf pairs. Mother/calf
pairs
accounted for 27% of all groups sighted, which is one of the highest sighting
rates reported among North Pacific wintering areas. Sixty percent of sightings
occurred in depths <50 m. Average sea surface temperature was 28.6◦C (±1.0
SD). Ninety percent of the 77 unique whales photo-identified were also seen in
the California–Oregon–Washington feeding aggregation. The 1999 survey showed
that humpback whales were widely distributed along the Central American coast at
relatively low densities. The extensive distribution of animals, the higher
proportion of calves, and the almost exclusive migration to a single feeding
area contrast with observations in other regions.
Thank you,
Kristin