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

COMPTUEX/JTFEX EA/OEA Final Chapter 3column (Dolphin, 1987; Dietz et al., 2002). Humpback whales on the wintering grounds do dive deeply;Baird et al. (2000) recorded dives deeper than 100 m.Acoustics—Humpback whales are known to produce three classes of vocalizations: (1) “songs” in thelate fall, winter, and spring by solitary males; (2) sounds made within groups on the wintering (calving)grounds; and (3) social sounds made on the feeding grounds (Thomson and Richardson, 1995). The bestknowntypes of sounds produced by humpback whales are songs, which are thought to be breedingdisplays used only by adult males (Helweg et al., 1992). Singing is most common on breeding groundsduring the winter and spring months, but is occasionally heard outside breeding areas and out of season(Matilla et al., 1987; Clark and Clapham, 2004). There is geographical variation in humpback whalesong, with different populations singing different songs, and all members of a population using the samebasic song. However, the song evolves over the course of a breeding season, but remains nearlyunchanged from the end of one season to the start of the next (Payne et al., 1983). Social calls are from50 Hz to over 10 kHz, with the highest energy below 3 kHz (Silber, 1986).Female vocalizations appear to be simple; Simão and Moreira (2005) noted little complexity. The malesong, however, is complex and changes between seasons. Components of the song range from under 20Hz to 4 kHz and occasionally 8 kHz, with source levels of 144 to 174 dB re 1 μPa m, with a mean of 155dB re 1 μPa-m. Au et al. (2001) recorded high-frequency harmonics (out to 13.5 kHz) and source level(between 171 and 189 dB re 1 μPa-m) of humpback whale songs. Songs have also been recorded onfeeding grounds (Mattila et al., 1987; Clark and Clapham, 2004).The main energy lies between 0.2 and 3.0 kHz, with frequency peaks at 4.7 kHz. “Feeding” calls, unlikesong and social sounds, are highly stereotyped series of narrow-band trumpeting calls. They are 20 Hz to2 kHz, less than 1 sec in duration, and have source levels of 175 to 192 dB re 1 μPa-m. The fundamentalfrequency of feeding calls is approximately 500 Hz (D’Vincent et al., 1985).No tests on humpback whale hearing have been made. Houser et al. (2001) constructed a humpbackaudiogram using a mathematical model based on the internal structure of the ear. The predictedaudiogram indicates sensitivity to frequencies from 700 Hz to 10 kHz, with maximum relative sensitivitybetween 2 and 6 kHz.Minke Whale (Balaenoptera acutorostrata)Status—The minke whale is not listed as endangered under the ESA, and theCalifornia/Oregon/Washington Stock and is not considered depleted or strategic under the MMPA. In theNortheast Pacific Ocean, minke whales range from the Chukchi Sea south to Baja California(Leatherwood et al., 1987). They occur year-round off California (Dohl et al., 1983; Barlow, 1995;Forney et al., 1995). The minke whales found in waters off California, Oregon, and Washington appearto be resident in that area, and to have home ranges, whereas those farther north are migratory. Thepopulation abundance for offshore California, Oregon, and Washington as a whole was estimated to be585 (CV=0.73) individuals (Carretta et al., 2005).Distribution—The minke whale generally occupies waters over the continental shelf, including inshorebays and estuaries (Mitchell and Kozicki, 1975; Ivashin and Vitrogov, 1981; Murphy, 1995; Mignucci-Giannoni, 1998; Calambokidis et al., 2004). However, based on whaling catches and surveys worldwide,there is also a deep-ocean component to the minke whale’s distribution (Slijper et al., 1964; Horwood,1990; Mitchell, 1991; Mellinger et al., 2000; Roden and Mullin, 2000).Minke whale abundance in the Southern California Bight fluctuates dramatically through the year, withwarm-water months being the period of greatest abundance (Dohl et al., 1981). Because of the apparent3-37 February 2007