insects

Vancouver Island is home to an abundance of wildlife and their related ecosystems. Some of these are now threatened due to urban advancement and habitat degradation. Some of the species at risk are as follows: MARBLED MURRELET (Brachyramphus marmoratus) The marbled murrelet, a small seabird which nests in the coastal, old-growth forests of the Pacific Northwest, is listed as a threatened species under the Endangered Species Act. In North America, the birds’ range stretches along the Pacific coast from the Bering Sea to central California with the largest populations occurring in southeastern Alaska and northern British Columbia. The murrelet’s dependence on old-growth nesting habitat and use of coastal marine feeding areas have brought it into frequent conflict with human economic interests, especially in the southern portion of its range where small, geographically concentrated populations are especially vulnerable to extirpation. However, both natural and human-related factors may be contributing to the species’ decline; potential causes include the loss of suitable nesting habitat, accidental death in gill-nets, oil pollution, increases in predator populations, and declines in food supplies due to recent El Nino events. The Marbled Murrelet could easily lay claim to the title “most mysterious bird on the Pacific coast of Canada.” It nests on the mainland in almost total obscurity, although people who fish and boat along the British Columbia coast during spring and summer (when the birds are nesting) often see Marbled Murrelets out on the water. Amazingly, in the 200 years that the species has been known to science, observers in British Columbia have seen only one occupied nest, in 1990. The story is the same over the whole of the murrelet’s North Pacific range (see map). To date, there are just over a dozen recorded sightings of occupied nests from Canada, Japan, Russia, and the United States. PURPLE MARTINS (Progne subis) The Purple Martin is a conspicuous bird in many populated areas of North America during spring and summer. Averaging 17 to 20 cm in length, it is Canada’s largest swallow. The Purple Martin resembles other swallows in having a slender body, long wings, and a wide beak. The tail is forked but not deeply as in some other swallows. Male martins, with their dark plumage, often appear to be black, but on bright sunny days their shiny blue-black coloration is clearly visible. Female martins are lighter in colour, with a pale grey throat and belly. By the time they have left the nest, young martins of both sexes resemble adult females. Young males only become dark at their second breeding season. The Purple Martin breeds throughout much of southern Canada, including Nova Scotia, the southern portions of New Brunswick, Quebec, Ontario, and Manitoba; southern and central Saskatchewan; and north-central Alberta. In British Columbia, martins are found in the Peace River region, southern Vancouver Island, and the extreme southwestern mainland. Martins are much less common in western Canada than in the eastern provinces. Martins arrive in Canada in early spring, usually in early April in Quebec and Ontario and from late April to early May in other areas. Martins have been banded, or tracked by placing a numbered aluminum band around the leg, for many years. Recoveries of banded martins have provided extensive information about the movement of these long-distance migrants. Of the adult birds banded and sighted again, most had returned to the breeding colonies where they were banded or to one near by. Banded nestlings have also typically returned to their home colonies to breed, although a few young bred hundreds of kilometers from their birthplace. Banding has also provided information on the lifespan of martins. Most martins live to four or five years. The oldest martin on record is an eight-year-old recaptured at its breeding colony. The ability of martins to find their colony is remarkable. In one experiment, adults that were transported several hundred kilometers from their nesting colonies returned in a matter of days. SHARP TAILED SNAKE (Contia tenuis) This is a small, slender snake 20-45 cm from snout to vent. It is coppery or reddish on the back, with darker sides. The belly is whitish with a half-moon shaped crossbar on each scale. The tail is tipped with a small spine. A variety of habitats are used by this snake ranging from Garry oak grasslands to forest. It is usually found near water or in clearings near forests. When the soil is damp it spends much of time under rocks or logs, but when the soil dries out it will retreat underground. Sharp-tailed snakes are rare, and seem to occur in widely scattered populations. They are most active on the surface in early spring and again in late fall. They eat primarily small slugs, and have special long teeth for biting them. It is a Red-listed species in BC and confirmed occurrences of sharp-railed snakes have been recorded at only seven locations in BC, all on southern Vancouver Island and the Gulf Islands. These snakes are very secretive and hard to find, making population sized difficult to estimate. In BC, sharp-tailed snakes are at the northern extremity of their range, and it is unlikely they were ever abundant. Conservation efforts have recommended private landowners avoid using pesticides and chemical slug-bait, and try to maintain natural area with protective cover in your yard. COMMON RINGLET (Coenonympha california insulana) The common ringlet’s wing colour ranges from dark orange-brown to pale cream with the underside of the forewing usually having a small eyespot near its tip. The underside of hindwing is gray-green with a wavy white median line and has a total wing span of 1 1/3 – 1 1/2 inches (3.4 – 3.8 cm) and they have a characteristic bouncing flight pattern. This butterfly is extremely variable geographically, with at least 4 subspecies. They may be found in suitable habitats in the Pacific Northwest from southwestern BC to Oregon, including the San Juan Islands and Garry oak ecosystems. In the 1950’s this subspecies was one of the most abundant butterflies on Vancouver