North Pacific right whale (Eubalaena japonica) COSEWIC assessment and status report: chapter 4

Distribution

Global range

E. japonica was once abundant in the North Pacific. Concentrations of right whales were found and exploited in the Gulf of Alaska, eastern Aleutian Islands, south-central Bering Sea, Sea of Okhotsk, and Sea of Japan and offshore waters across much of the North Pacific (Braham and Rice 1984, Scarff 1991, Clapham et al. 2004). Figure 2, replicated from Townsend (1935), shows historical whaling data for right whales in the eastern North Pacific from logbook records of American whaleships. Scarff (1991) notes that the apparently discrete populations of right whales in the eastern and western North Pacific reflected in the Townsend charts may be an artifact of the non-random distribution of whalers in the North Pacific and their concentration on the eastern (Gulf of Alaska “Northwest Ground”) and western (Kamchatka/Sea of Okhostk) areas.

Today the distribution and stock structure of North Pacific right whales is poorly understood (Brownell et al. 2001). There are very few data on the current summering and wintering grounds of the eastern North Pacific right whale. According to Gaskin (1987), whaling data assembled by Nemoto (1957, 1959, and 1962) and Gaskin (1976) suggests that most remaining eastern North Pacific right whales occur in summer on the southeastern shelf of the Bering Sea, around the eastern Aleutian Islands, and Kodiak Island. Further studies of historical concentrations and some recent summer sightings indicate that the Bering Sea and Gulf of Alaska may contain important feeding grounds (Scarff 1986, Scarff 1991, Goddard and Rugh 1998, Moore et al. 2000, Brownell et al. 2001, Clapham et al. 2004, Mellinger et al. 2004). The location of calving grounds is unknown.

Twentieth century sightings support a two stock hypothesis where there appear to be two populations in the North Pacific, at least with regard to concentrations on feeding grounds--one in the east and one in the west, with the possibility that the western group may occur in two separate sub-populations (Klumov 1962, Brownell et al. 2001). However, this division of populations is not conclusive, and remains open (IWC 2001a).

Post-whaling sightings have been reported as far south as central Baja California in the eastern North Pacific, as far south as Hawaii in the central North Pacific and as far north as the sub-Arctic waters of the Bering Sea and Sea of Okhotsk in the summer (Gilmore 1956, Herman et al. 1980, Berzin and Doroshenko 1982, Bruggeman et al. 1984, Scarff 1986, Gaskin 1987, NMFS 1991, Gendron et al. 1999, Salden and Mickelson 1999).

Figure 2. Map of historical right whale catches in the eastern North Pacific from logbook records of American whale ships (replicated from Townsend 1935). The dot colour represents month of catch.

Figure 2.  Map of historical right whale catches in the eastern North Pacific from logbook records of American whale ships (replicated from Townsend 1935). The dot colour represents month of catch.

Canadian range

Presently, there are not any known concentrations of eastern North Pacific right whales in Canadian waters. There has not however, been any significant sighting effort in recent decades. Historical distribution from offshore whaling data (1785-1913) show that right whales were present in British Columbia waters during the months of April to October (Townsend 1935, Clapham et al. 2004), possibly feeding or migrating to or from calving grounds (Figure 2).

20th Century British Columbia whalers (1900-1951) who operated mainly in coastal waters took only seven right whales (Figure 3 and Table 1). The last right whale sighting that may have been in British Columbia waters was in 1970 by S. Wada while on board a Japanese scoutboat west of the Queen Charlotte Islands (Table1). However, due to the range of coordinates given for this sighting, it is possible that this sighting took place outside British Columbia waters. Braham (1986) published a reference to an unconfirmed sighting of a right whale at Swiftsure Bank on the Canadian side near the mouth of the Strait of Juan de Fuca in 1983 (Reeves and Leatherwood 1985 in Braham 1986). However, further investigation indicates uncertainty about the species identification.

Figure 3. Right whale sightings/catches in British Columbia waters and in US water adjacent to the Canadian border, 1900-2002. Note that 1) coordinates were not found for the catches positioned at whaling stations, and 2) the range of coordinates for the 1970 Wada sighting are too broad to plot on this map.

Figure 3. Right whale sightings/catches in British Columbia waters and in US water adjacent to the Canadian border, 1900-2002. Note that 1) coordinates were not found for the catches positioned at whaling stations, and 2) the range of coordinates for the 1970 Wada sighting are too broad to plot on this map.

There have not been any confirmed sightings in Canadian waters for over five decades. However, between 1959 and 1992, three sightings of seven animals were recorded in US waters near the B.C./Washington border in close proximity to Canadian waters (Figure 3, Table 2). In the period 1958 and 1977, only seven offshore records exist (i.e. outside the 200 mile limit to 145° W) (Table 3).

Table 1. Right whale catches and sightings in British Columbia waters, 1900-2002
Date Location Type Number Reference
June, 1914 Naden Harbour (no coordinates) Catch
1
Nichol et al. 2002
June, 1918 Rose Harbour (no coordinates) Catch
1
Nichol et al. 2002
June 15, 1924 Naden Harbour (54°35 N, 133°55 W) Catch
1
Nichol et al. 2002
June 24, 1924 Naden Harbour (54°05 N, 133°40 W) Catch
1
Nichol et al. 2002
June 10, 1926 Naden Harbour (53°40 N, 133°45 W) Catch
1
Pike and MacAskie 1969
June 10, 1929 Rose Harbour (no coordinates) Catch
1
Nichol et al. 2002
July 18, 1951 Coal Harbour (50° N, 128° W) Catch
1
Pike and MacAskie 1969
1970 W of Queen Charlotte Islands (50-55° N, 130-140° W) Sighting
2
Wada 1975Footnotea
1983 Juan de Fuca Strait (48° 33 N, 124° 39 W) Sighting
2
Reeves and Leatherwood 1985 in Braham 1986Footnoteb

 

Table 2. Right whale sightings in waters adjacent to Canadian waters, 1900-2002
Date Location Number Reference
April 8, 1959 SW of Grays Harbour, Washington (45°55 N, 125°25 W)
3
Fiscus and Niggol 1965
January 17, 1967 W of Cape Flaherty, Washington (48°20 N, 125°06 W)
3
Rice and Fiscus 1968
May 24, 1992 NW of Grays Harbour, Washington (47°17 N, 125°11 W)
1
Rowlett et al. 1994

 

Table 3. Offshore right whale sightings, 1900-2002
Date Location Number Reference
1958-1967 50° N, 145° W
2
Pike and MacAskie 1969
1958-1967 54° N, 155° W
1
Pike and MacAskie 1969
1963 51° N, 145° W
200
Berzin and Doroshenko1982 (cited in Brownell et al. 2001)Footnotec
1973 45-50° N, 140-150° W
1
Wada 1975
1974 40-50° N, 140-160° W
1
Anonymous 1976
1975 40-45° N, 140-150° W
2
Wada 1977
1977 40-50° N, 140-145° W
1
Wada 1979
1977 45-50° N, 135-140° W
2
Wada 1979

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