Hot Springs Cove, Colombie-Britannique
The Hesquiat Lake Area is in the central part of the west coast of Vancouver Island, British Columbia, and as defined here includes most of the piece of land between Hesquiat Lake, Hesquiat Harbour, Stewardson Inlet and the Sydney River. More precisely it covers the adjacent watersheds of the rivers leading into Hesquiat Lake and the Hesquiat Point Creek watershed.
Western Hemlock dominates the forest in the lowest vegetation zone, although Sitka Spruce forms a narrow belt adjacent to the ocean. Western Redcedar at lower elevations and Yellow Cedar at higher elevations are common tree species, while Amabilis Fir, Shore Pine and Red Alder also occur.
This and three other forested sites on Vancouver Island in British Columbia have been identified as IBAs for breeding Marbled Murrelets (a nationally threatened species) even though it is still uncertain whether these are the best Canadian sites for the species. Given the state of the information at this time (early 2001) it appears that these sites are probably amongst the highest quality sites, but others may be equally as good, or better. Since the species is very difficult to survey, the habitats and favoured breeding areas are poorly known. The IBA includes the whole watershed because Marbled Murrelets may breed in both low and high elevation areas, although most researchers believe that lower elevation forests are preferred.
In 1991, surveys were conducted at 140 sites throughout Vancouver Island. These surveys used visual and auditory detections to assess the use of an area by breeding season Marbled Murrelets. Although this method does not give population estimates and is a somewhat weak method it does give some idea of the comparative use of areas. Together the Hesquiat Lake station and the Hesquiat Creek Station had 250 detections in the 1991 survey - this was one of the highest detection rates.
Between 1996 and 1998, University of Victoria and BC Ministry of the Environment researchers conducted radar surveys of a large section of western Vancouver Island located between Hesquiat Peninsula and the Kennedy River. These radar surveys are thought to be more accurate than the detection surveys as they record all the birds flying into a watershed at dawn. There is still uncertainty over whether all birds detected are using the associated watershed, but most are thought to be. The average number (average within each three years averaged) of murrelets flying into these two watersheds in this survey was 336. This is a little under 1% of the estimated Canadian Marbled Murrelet population. The maximum recorded in a single day at Hesquiat Lake alone was 355 and at Hesquiat Point Creek was 284. One of the reasons that this site has been included is because a crude density estimate (number of birds/area of watershed) results in Hesquiat Point Creek watershed having the highest density of murrelets out of the twenty watersheds surveyed by the researchers. It should also be noted that it is not known what portion of murrelets recorded in the radar surveys are actively breeding birds.
Hesquiat Lake Park is a potential BC Ecological Reserve. Since these two watersheds are not in protected areas they are susceptible to logging, which seriously affects the breeding success of Marbled Murrelets by the removal of their nesting habitat.Catégories ZICO Habitats Usages Menaces Potencielles ou Existantes Status de Protection
|336 - 355||1997||Été|