Living Marine Legacy of Gwaii Haanas
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Data on these species are often grouped Glaucous-winged Gull together as it can be difficult to distinguish between them during boat-based or aerial Glaucous-winged Gulls tend to nest on surveys. These gulls are abundant in all treeless sections of small, low, offshore seasons in the marine waters around the islands or on rocky headlands (Campbell et archipelago (Campbell et al. 1990 b). In al. 1990 b). They build nests and lay up to spring, concentrations of 400 to 600 have three eggs. The chicks are fed during the been recorded in Hecate Strait, Dixon day, mainly on fish and invertebrates. The Entrance and west of Kunghit Island adults are surface feeders. Their (Campbell et al. 1990 b). Gaston and Jones reproductive success in Skidegate Inlet was (1991) noted that numbers near Reef Island studied by Vermeer et al. (1991 a). were quite variable between years. For example, numbers were low in April 1984, Approximately 2,800 pairs breed in small but 4,000 to 5,000 were counted in April colonies or solitarily on Haida Gwaii 1987. In the summer and fall, these species (Rodway 1988; Vermeer et al. 1991 a, 1997 c). were most abundant near or beyond the The locations of known breeding sites are shelf break off the west coast. Together the shown in Figure 11. The archipelago two species made up ~30% of the birds off supports ~11% of the British Columbia the west coast in September. However, population and <2% of the breeding Herring Gulls are also seen close to shore population of the northeastern Pacific during these seasons. Cannings (1975) (Campbell et al. 1990 b). reported ~250 adults and ~250 immatures feeding off the tip of Rose Spit in July 1974 The breeding population in Haida Gwaii and Reimchen (1992 c) observed appears to be stable or increasing. congregations at Bag Harbour during Although a complete resurvey of all sites salmon migration. In winter most Herring has never been done, Rodway (1988) and Thayers Gulls were observed in reported a 30% increase between 1977 and shallow waters of Hecate Strait and 1986 on the islands that he rechecked. The numbers were lower. Hearne and Goudie total breeding population on five islands in (cited in Morgan 1997) found that Herring Laskeek Bay remained relatively stable Gulls were much more common than between 1992 and 1997, at a level slightly Thayers Gulls at Sandspit in spring, but higher than that recorded in 1986 (Rodway noted that the ratio was reversed in winter. 1988; Smith 2000). Some shifting between Most CBCs have recorded more Thayers sites was noted (Gray 1999). A large Gulls than Herring Gulls. While CBC totals increase in the Laskeek Bay population in in Port Clements and Rose Spit are usually 1998 was followed by a large decrease in <10 for each species, totals at the Skidegate 1999, but the latter result is confounded by count varied up to 49 and 126 for Herring an incomplete survey (Gray 1999). In 1990, and Thayers Gulls, respectively. Evidence Vermeer et al. (1991 a) found 178 breeding from surveys off the west coast of pairs when they resurveyed 13 colonies in Vancouver Island suggests that Herring Skidegate Inlet where 116 pairs had been Gulls are more pelagic than Thayers Gulls recorded in 1986 (Rodway 1988). However, (Vermeer et al. 1989). the difference in the results of the two studies probably reflects more a difference Breeding Bird Survey (BBS) results indicate in methodologies than a large increase in a positive, but not significant, trend in the gull population (Vermeer et al. 1997 c). Herring Gull numbers in British Columbia The population along the entire coast of from 1966-2000 (BBS website: http:// British Columbia increased ~350% from www.mbr-pwrc.usgs.gov/bbs/bbs00.html). 1940-1990 (Campbell et al. 1990 b). 38 39 The Glaucous-winged Gull is abundant Sabines Gulls migrate in large flocks well year-round on all marine waters around offshore (Campbell et al. 1990 b) and most Haida Gwaii. Numbers offshore sightings in the waters around Haida Gwaii (maximum in April and May) decline as the occur >30 km offshore. When flocks are birds move to their nesting sites. Relatively observed in nearshore waters, they usually few birds are found beyond the continental number <100 birds (Campbell et al. 1990 b). shelf from the beginning of breeding Low numbers have been recorded from through the winter. Spring counts of 600, spring through fall in Queen Charlotte 400 and 800 were made at Burnaby Island, Sound and Hecate Strait and year-round in Sandspit and Rose Spit, respectively Dixon Entrance (Campbell et al. 1990 b). (Savard and Kaiser 1982; Campbell et al. The largest flock seen near Reef Island 1990 b). In spring of some years, large numbered 30 to 40 in May 1985 (Gaston and flocks of hundreds of immatures were Jones 1991); M. Hearne (cited in Morgan recorded near Reef Island where they were 1997) observed >200 in May 1991 off observed feeding with adults on Pacific Masset. No Sabines Gulls have been herring shoals (Gaston and Jones 1991). recorded during CBCs. These and additional roosting and feeding sites are shown on Figure 4 and listed in Black-legged Kittiwake Table 10. Glaucous-winged Gulls are seen on or around their colonies during the In North America, Black-legged Kittiwakes breeding season and tend to roost on breed on islands in Alaska, Quebec and unvegetated islands (Butler 2000). In fall, Newfoundland. They are piscivorous this species congregates in estuaries to feed surface feeders and winter in marine on salmon carcasses (Reimchen 1992 a, c, habitats. 1994 b). High numbers are frequently reported from sites around the archipelago Black-legged Kittiwakes are abundant in all in winter. Christmas Bird Count totals of offshore waters during spring and fall 3365 at Rose Spit in 1988 and 1150 at migration. Birds are also frequently Skidegate Inlet in 1991 were the highest observed in inshore waters and are recorded. Glaucous-winged Gulls made up abundant from March through October 9% of the marine bird population and were (Hamel and Hearne 2001). Extremely large the most abundant species in the winter of interannual variations in spring numbers in 1991-1992 in Skidegate Inlet (Blood and Hecate Strait are known (Vermeer and Bentley 1992). Rankin 1984; Gaston and Jones 1991). Gaston and Jones (1991) recorded up to These gulls use freshwater as well as 10,000 near Reef Island in May 1985 (Figure marine waters on Haida Gwaii. Reimchen 4), but observed none in 1984. They also and Douglas (1984 b) observed gulls noted that while the majority seen in March making daily migrations between the ocean and April were in adult plumage, >90% of and Drizzle Lake. Birds were primarily those seen in May and June were night residents on the lake and were never immatures. Hundreds are seen in Laskeek observed foraging. Bay in June and July of most years (A. Gaston, CWS, personal communication) and Sabines Gull summer records of hundreds of kittiwakes have been reported from other marine Sabines Gulls breed in the Arctic and waters around the region including Hippa spend the non-breeding season at sea. They Island, Naden Harbour and Rose Spit prey on fish from surface waters. (Campbell et al. 1990 b). By September, numbers were highest off the west coast where they were estimated to have the 40 second highest standing stock of marine Strait, but occurs significantly less birds (Vermeer and Rankin 1984). frequently, and in smaller numbers, off the Kittiwakes are encountered on ~50% of the west coast. Birds are generally found in Rose Spit counts and <50% of the Masset higher densities in waters <100 m depth. CBCs, but totals are usually <10. The Numbers in Queen Charlotte Sound, maximum count during the winter of 1991- Hecate Strait and Dixon Entrance peak in 1992 in Skidegate Inlet was two (Blood and spring and fall. Noteworthy records Bentley 1992). include flocks of 100 to 600 at Cape St. James, Langara Island and Rose Spit in the Common Murre spring, 900 in Hecate Strait in the summer and >500 in Skidegate Inlet in the fall Common Murres nest colonially on cliff (Campbell et al. 1990 b). During fall and ledges and surfaces of rocky islands. winter, Common Murres were the most Campbell et al. (1990 b) suggested that common alcid in inlets (Savard 1979). Common Murre breeding sites may be Large numbers are regularly found in limited by the lack of suitable habitat in Skidegate Inlet in winter (Robertson 1974; British Columbia. Adults forage by Hatler et al. 1977) where Blood and Bentley pursuing fish underwater and provision (1992) counted a maximum of 439 near their single chick during the day. The Sandspit in winter 1991-1992. The birds are species natural history from British also abundant from Masset to Rose Spit in Columbia to California was reviewed by winter (Savard 1979; Coastal Waterbird Manuwal and Carter (2001). The Pacific Inventory File 1980; B.C. Coastal Waterbird subspecies is on the COSEWIC Candidate Survey website: www.bsc-eoc.org/ List as defined in Appendix A. bcwaterbirds.html; K. Vermeer, CWS, unpublished data); a high of 7,492 were The Kerouard Islands are the only counted during the Masset CBC in 1993. confirmed breeding site of Common Murres in Haida Gwaii. The breeding population Pigeon Guillemot on the Kerouards exhibits significant annual variation: an estimate of 400 Pigeon Guillemots nest solitarily or breeding birds was based on a 1987 count colonially usually in burrows or crevices, or (Rodway et al. 1990; Rodway 1991), but in among large boulders; they also nest at 1977 only 90 breeding birds were recorded industrial sites along the shore such as (Campbell et al.