NMFS Biological Opinion on U.S. Navy training ... - Govsupport.us

FINAL PROGRAMMATIC BIOLOGICAL OPINION ON U.S. NAVY ACTIVITIES IN THE HAWAII RANGE COMPLEX 2008-2013
Table 4. Rates of exchange among humpback whales in different sub-areas in the Hawai'ian Islands based on data
presented in Calambokidis et al. (2008). Numbers along the diagonal represent the total number of individuals that were
identified in a sub-area (highlighted in bold), number in the sub-diagonals represent the number of individuals from one
sub-area that were identified in other areas (for example, of the 203 humpback whales that were identified off Kaua’i, one of
those individuals was also identified off O’ahu). Numbers in parentheses represent percentages; percentages in bold
represent percentage of the total number of individuals identified in the Hawai'ian Islands, non-bold percentages represent
the percentage of humpback whales from one sub-area that were also counted in other sub-areas.
Sub-Area Kaua’i Oahu
Kaua’i
O’ahu
Penguin Bank
Moloka’i
Maui
Hawai’i
203
(0.0793)
1
(0.0049)
89
(0.0348)
Penguin
1 Moloka’i Maui Hawai’i
Bank
0
(0.0000)
0
(0.0000)
34
(0.0133)
4
(0.0197)
5
(0.0562)
3
(0.0882)
201
(0.0785)
29
(0.1429)
20
(0.2247)
4
(0.1176)
61
(0.3035)
1526
(0.596`)
2
(0.0099)
9
(0.1011)
3
(0.0882)
12
(0.0597)
99
(0.0649)
507
(0.1980)
1. Penguin Bank is located off the southwest tip of the island of Molokai and is an important shallow, marine habitat that is part of
the Hawai’ian Islands Humpback Whale National Marine Sanctuary
contemporary breeding aggregations occur off the Greater Antilles where humpback whales from all of the North
Atlantic feeding areas have been identified from photographs (Katona and Beard 1990, Clapham et al. 1993b,
Mattila et al. 1994, Palsbøll et al. 1997, Smith et al. 1999, Stevick et al. 2003a). Historically, an important breeding
aggregation was located in the eastern Caribbean based on the important humpback whale fisheries this region
supported (Mitchell and Reeves 1983, Reeves et al. 2001, Smith and Reeves 2003). Although sightings persist in
those areas, modern humpback whale abundance appears to be low (Winn et al. 1975, Levenson and Leapley 1978,
Swartz et al. 2003). Winter aggregations also occur at the Cape Verde Islands in the Eastern North Atlantic (Reiner
et al. 1996, Reeves et al. 2002, Moore et al. 2003). In another example of the “open” structure of humpback whale
populations, an individual humpback whale migrated from the Indian Ocean to the South Atlantic Ocean and
demonstrated that individual whales may migrate from one ocean basin to another (Pomilla and Rosenbaum 2005).
INDIAN OCEAN. As discussed previously, a separate population of humpback whales appears to reside in the Arabian
Sea in the Indian Ocean off the coasts of Oman, Pakistan, and India (Mikhalev 1997).
Threats to the Species
NATURAL THREATS. There is limited information on natural phenomena that kill or injure humpback whales. We
know that humpback whales are killed by orcas (Dolphin 1989, Florez-González et al. 1984, Whitehead and Glass
1985) and are probably killed by false killer whales and sharks. Because 7 female and 7 male humpback whales
stranded on the beaches of Cape Cod and had died from toxin produced by dinoflagellates between November 1987
and January 1988, we also know that adult and juvenile humpback whales are killed by naturally-produced biotoxins
(Geraci et al. 1989).
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