The following paper has just been published:
Stafford, K.M., D.K. Mellinger, S.E. Moore, and C.G. Fox. 2007. Seasonal
variability and detection range modeling of baleen whale calls in the Gulf of
Alaska, 1999-2002. J. Acoust. Soc. Am. 122:3378-3390.
Five species of large whales, including the blue (Balaenoptera musculus), fin (B.
physalus), sei (B. borealis), humpback (Megaptera novaeangliae), and North Pacific
right (Eubalaena japonica), were the target of commercial harvests in the Gulf of
Alaska (GoA) during the 19th through mid-20th Centuries. Since this time, there have
been a few summertime visual surveys for these species, but no overview of year-round
use of these waters by endangered whales primarily because standard visual survey data
are difficult and costly. From October 1999-May 2002, moored hydrophones were deployed
in six locations in the GoA to record whale calls. Reception of calls from fin,
humpback, and blue whales and an unknown source, called Watkins’ whale, showed
seasonal and geographic variation. Calls were detected more often during the winter
than during the summer, suggesting that animals inhabit the GoA year-round. To
estimate the distance at which species-diagnostic calls could be heard, par
abolic equation propagation loss models for frequencies characteristic of each
of each call type were run. Maximum detection ranges in the subarctic North
Pacific ranged from 45 to 250 km among three species (fin, humpback, blue),
although modeled detection ranges varied greatly with input parameters and
choice of ambient noise level.
Reprints are available at
ftp://newportftp.pmel.noaa.gov/newport/mellinger/Stafford07-GoAWhalesAndDetectionRange.pdf
|