August 4, 2015 Biodiversity No Comments
endangered polar bear

Canada’s majestic mountains, plains and

oceans are filled with an equally impressive range of diverse species. However, despite a wealth of legislation designed to safeguard these animals, there are some who criticize the country for concentrating on mitigation rather than protection¹. And it is this lack of focus which has caused many of these species to walk along the path to extinction.

The most recognizable and charismatic of Canada’s species is the polar bear, which has become an icon for environmental awareness. Churchill in Manitoba is one of the few places where it is possible to see these majestic animals in the wild, with prime viewing times in October and November². Although some might dispute the fact that polar bears are in fact in decline, with populations claimed to be on the increase, they are still listed as vulnerable on the IUCN Red List³,. Their greatest threat is that of climate change, with melting ice forcing them ever northwards, restricting their habitat until there is nowhere left to go. This also impacts on their food supply. Reductions in ice-loving algae, which form the bottom of the polar bear’s food chain, will cause knock-on effects in their preferred diet of seals. As apex predators, they are also vulnerable to the effects of pollutants, such as organochlorines, which magnify the further up the food chain they go. Some areas of the Arctic have higher levels of pollutants, including those inhabited by polar bears, and it is thought this might also contribute to declining numbers.

At the other end of the scale, a number of tiny but important creatures are also under threat. The smallmouth salamander is currently stable across the US, but in Canada it is only found in Southern Ontario. It inhabits tall grass prairies, hardwood forests and farm land but has lost much of its breeding grounds, while decreases in water levels during its breeding and larval periods from March through June, also limit its numbers. Adding to its problems is a lack of specific legislation to protect it.

Despite its name, the cucumber tree does not produce cucumbers, but is again under threat in Canada. This attractive leafy plant, with its greenish-yellow flowers, is widespread in the US but restricted to south-western Ontario in Canada. The most recent studies of the cucumber tree reveal only 15 natural sites where it is found, with only around 200 individual specimens remaining, most of which are on private ground. They require rich, moist acidic soil and prefer forests with openings as they are shade intolerant. Unfortunately, much of this has been cleared for agricultural purposes and logging, restricting potential habitat while the species also possesses a naturally low reproductive ability, which together contribute to its threatened status.

The delightfully named mudpuppy mussel, or salamander mussel as it is also known, is a small freshwater species of mollusc that grows to around 50mm. Its shells varies from yellowish tan to dark brown and despite being protected under the federal Species at Risk Act (SARA) and the Fisheries Act, it is restricted to a 50km stretch of the East Sydenham River in south-western Ontario. It prefers sand or silt under large rocks, in areas which are shallow and which have a fast current but the most important factor is the presence of cover which needs the needs of its larval host, the mudpuppy salamander. The mussel is not well studied but threats to the species include siltation, pollution, channel modification and the presence of the predatory zebra mussel, which is an invasive species.

Canada’s waters are also home to such travelling giants as blue whales, great white sharks, beluga whales, and gray whales, while cougars, wolverines, bison and pine martens roam its lands, all of which are of concern to conservationists. However, with the news that blue whale populations are on the rise thanks to the moratorium on whaling gives hope to the possibility that other species, if offered suitable protection, might too recover and restore this great land to its natural state.



Written by Greentumble Editorial Team