Composite Training Unit Exercises and Joint Task ... - Govsupport.us

COMPTUEX/JTFEX EA/OEA Final Chapter 3Historically, sei whales occurred in the California Current off central California (37ºN–39ºN), and theymay have ranged as far south as the area west of the Channel Islands (32º47’N) (Rice, 1977). A few earlysightings were made in May and June, but they were encountered there primarily during July–September,and had left California waters by mid-October.Three sightings were made north of the SOCAL Range Complex in the PMSR during the warm-watermonths (June–September); there were two sightings north of Point Conception and one sighting south ofthe western tip of Santa Cruz Island (U.S. Navy, 1998). Recently, only one confirmed sighting of seiwhales and five possible sightings (identified as either sei or Bryde’s whales) were made in Californiawaters during extensive ship and aerial surveys during 1991–1993 (Mangels and Gerrodette, 1994;Barlow, 1995; Forney et al., 1995). The confirmed sighting was more than 200 nm (370 km) off northernCalifornia. No sei whales were sighted during the recent NMFS/SWFSC surveys in 1998–1999 (Carrettaet al., 2000). Sei whales are found in the SOCAL OPAREA from May through October (U.S. Navy,1998).Acoustics—Sei whale vocalizations have been recorded only on a few occasions. They consist of pairedsequences (0.5 to 0.8 sec, separated by 0.4 to 1.0 sec) of 7 to 20 short (4 milliseconds [msec]) frequencymodulated sweeps between 1.5 and 3.5 kHz; source level is not known (Richardson et al., 1995). Whileno data on hearing ability for this species are available, Ketten (1997) hypothesized that mysticetes haveacute infrasonic hearing.Historically, sei whales occurred in the California Current off central California (37ºN–39ºN), and theymay have ranged as far south as the area west of the Channel Islands (32º47’N) (Rice, 1977). A few earlysightings were made in May and June, but they were encountered there primarily during July–September,and had left California waters by mid-October.3.3.2.6.2 Odontocete Cetaceans (Dolphins and Tooth Whales)Baird’s Beaked Whale (Berardius bairdii)Status—Baird’s beaked whale is not listed as endangered under the ESA, and theCalifornia/Oregon/Washington Stock is not considered strategic under the MMPA. The minimumpopulation estimate for the California/Oregon/Washington Stock is 152 (CV=0.51) individuals (Carrettaet al., 2005).Distribution—Baird’s beaked whales appear to occur mainly in deep waters over the continental slope,oceanic seamounts, and areas with submarine escarpments (Ohsumi, 1983; Kasuya and Ohsumi, 1984;Willis and Baird, 1998; Kasuya, 2002). They may be seen close to shore where deep water approachesthe coast (Jefferson et al., 1993) and in shallow waters in the central Okhotsk Sea (Kasuya, 2002).Baird’s beaked whales are infrequently encountered along the continental slope and throughout deepwaters of the eastern North Pacific (Forney et al., 1994; Barlow et al., 1997). No sightings were madeduring the 1998–1999 NMFS surveys of the SCIRC (Carretta et al., 2000). All Baird’s beaked whalesfound in the SOCAL Range Complex are expected to be found in non-territorial waters. There are fewsightings of Baird’s beaked whales in the SOCAL OPAREA, sightings occurred in both the cold andwarm seasons (U.S. Navy, 1998).Acoustics—MacLeod (1999) suggested that beaked whales use frequencies of between 300 Hz and 129kHz for echolocation, and between 2 and 10 kHz, and possibly up to 16 kHz, for social communication.Both whistles and clicks have been recorded from Baird’s beaked whales in the eastern North PacificOcean (Dawson et al., 1998). Whistles had fundamental frequencies between 4 and 8 kHz, with 2 to 33-41 February 2007