90 
Table 1 
Fishery Bulletin 120(1) 
Observed mortalities of killer whales (Orcinus orca) recorded from 1991 through 2016 by observers 
aboard vessels in various Alaska Bering Sea and Aleutian Islands fisheries. 
No. of individuals (fishery) 
Year Killed by gear 
1991 
1992 
1993 
1994 
1995 
1996 
1997 
1998 
1999 
1 (pollock trawl) 
1 (pollock trawl) 
1 (flatfish trawl) 
1 (Pacific cod longline) 
1 (pollock trawl) 
1 (Greenland turbot longline; 
1 (pollock trawl) 
2000 
2001 
2002 
2003 
1 (pollock trawl) 
1 (pollock trawl); 
1 (Pacific cod longline) 
2004 
2005 
2006 
2007 1 (Greenland turbot longline) 
2008 
2009 
2010 
2011 
2012 
2013 
2014 
2015 
2016 
1 (Pacific cod longline) 
1 (Greenland turbot longline) 
1 (Pacific cod longline) 
Fishery type 
Trawl 
Longline 
Total 
is unknown. Resident killer whales are very social ani- 
mals that occur in distinct, stable pods. During periods of 
socialization and foraging, resident pods are known to join 
other resident pods temporarily (Bigg et al., 1990). During 
these multi-pod assemblages, individuals can share and 
subsequently learn certain behaviors (Whitehead, 2007). 
Over time, it is likely that more groups of killer whales 
will learn this behavior and begin targeting commercial 
fisheries where prey are easily located and available. 
Documented injuries to killer whales range from minor 
to severe. Although some injuries appear to be life threat- 
ening, it is difficult to determine if an injury would lead to 
mortality of a whale. For example, the killer whale with 
Killed by propeller 
1 (flatfish trawl) 
2 (flatfish trawl) 
2 (flatfish trawl) 
1 (flafish trawl) 
2 (Atka mackerel trawl) 
1 (rockfish trawl) 
Previously dead 
1 (flatfish trawl) 
1 (flatfish trawl) 
1 (flatfish trawl) 
1 (pollock trawl) 
1 (Pacific cod longline) 
1 (flatfish trawl) 
1 (pollock trawl) 
1 (flatfish trawl); 
1 (Pacific cod trawl) 
1 (flatfish trawl) 
1 (Atka mackerel trawl); 
1 (Pacific cod trawl) 
2 (Pacific cod trawl) 
1 (Pacific cod longline) 
1 (Pacfic cod longline) 
1 (flatfish trawl) 
No. of individuals 
the cut-off dorsal fin and severe head injury was seen feed- 
ing off discards. A killer whale in New Zealand that had 
its dorsal fin split into 2 parts reportedly lived for 2 years 
after the injury occurred (Visser and Fertl, 2000). It is 
unknown whether, but likely that, these severe injuries 
could be responsible for an early death. With all degrees 
and types of injuries, healing requires energy that could 
possibly lower a whale’s resistance to disease. The under- 
lying cause of a collapsed dorsal fin is unknown but could 
be attributable to either an injury or a whale’s overall 
health, including nutritional issues. 
Over half of the killer whales that were either killed 
by gear or killed by propellers and whose ecotype was 
