Killer Whale
Orcinus orca
Killer Whale
Conservation
Ford et al. (2000) summarized three conservation issues for
killer whales in southern British Columbia and Washington
State as food shortages, industrial contaminants, and vessel
disturbance. Dwindling food supplies notably in Chinook salmon
stocks from overfishing, habitat degradation and changes in
the ocean environment are possible causes for low reproductive
success. Couple food shortages with contamination most notably
from PCB and dioxins in the tissues of the whales (Ross et al.
2000) and concerns for the whales’ ability to reproduce appear
justified. Finally, the sudden interest in whale watching has
brought a near constant bevy of boats around the whales.
Industry standards are in place so that the commercial whale
watching companies keep their distance from the whales but
recreational boaters are not always as responsible (Trites &
Bain 2000). For a vocal species like the killer whale,
underwater noise from the boats might be the bigger problem in
the end.
The southern resident killer whale were designated an
‘endangered’ species under Canada’s Species at Risk Act in
2004,
by the State of Washington in 2004, and by the U.S. National
Marine Fisheries in 2005. The Department of Fisheries and
Oceans Canada and the US national Marine Fisheries Service are
responsible for killer whales in Canada and the USA,
respectively and they are writing a plan for recovery. The
basis of the designation is a decline in abundance in recent
years.
The southern resident population was estimated to have about
110 whales in the mid1960’s of which about 34 individuals were
lost to aquaria between 1967 and 1972. The population rose
from 67 to 83 whales by 1980 but it was followed by a decline
to about 73 killer whales by 1984. by 1995, the population had
risen to 97 individuals and dropped by 2001 to 78 whales
(Center for Whale Research 2001).
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