BC and Species at Risk

Archived Topic Box from the 2005 Fifth Annual Benchmark Report

British Columbians are fortunate to live in a region of vast biological diversity, with a society, culture and economy that have all been heavily influenced by the richness of our natural surroundings. But the benefits of living in the country's most biologically diverse province bring with them a number of challenges in terms of balancing economic growth, population growth, and human development with the protection of our natural endowments.

In order to better understand, and thereby protect, the province's numerous species, a number of attempts have been made at both the provincial and federal levels to identify and track the state of our species and ecosystems, specifically those species that are designated "at risk" or in danger of disappearing. Under Canada's constitution wildlife regulation is not clearly allocated to either the federal or provincial governments. At the federal level the task of assessing and listing threatened species has fallen to the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), which currently has close to 500 species in various "at risk" categories on its list. The federal government then selects species from this list to be protected under the 2003 Species at Risk Act (SARA), which protects designated species on federal lands across the country (including national parks and First Nations reserves), as well as migratory birds and aquatic species, which are designated as "federal species" under the Act. While the Act does provide some protection for threatened species, the scope of this protection is limited only to a small percentage of BC's land mass and species, with the protection of the remainder up to the province.

There are more than 70,000 known species in Canada, and 70,000 unknown are estimated. The species currently covered in the COSEWIC list represent less than one percent of the total known species in Canada. COSEWIC investigates only those species suspected of being at risk because of the expense and time it takes to classify a species. This sensible policy can lead to invalid conclusions about species at risk because a high percentage of the species investigated (70.9 percent, or 487 of 687) end up classified as being at risk of extinction. COSEWIC stresses that increasing numbers of at risk or extinct species on their list over time does not signify an increase in the number of at risk or extinct species in Canada, but is due to an increase in the number of species that have been investigated.

In BC, the task of measuring and assessing species is the responsibility of the BC Conservation Data Centre (CDC), which lists and tracks species that may be at risk or require further investigation. The CDC, uses an objective set of criteria to categorize species into three lists: the "Red List" which lists those species in imminent danger of extirpation or extinction; the "Blue List" which lists those species that are "at risk" but not in immediate danger; and the "Yellow List" for all species not on the previous two lists and many that may require "watching" due to potential concerns.

In British Columbia there are 143 species of mammals, 454 birds, 20 amphibians, 19 reptiles, and 450 fish species known, and an estimated 50,000 to 70,000 invertebrates (including 35,000 insect species), 2,850 vascular plants, 1,000 mosses, 1,600 lichens, 522 attached algae and more than 10,000 fungi throughout the province. In total, there are between 67,000 and 87,000 species estimated in British Columbia.

It is difficult to estimate the proportion of total species at risk of extinction in Canada and BC because investigation is both time-consuming and costly and because we know very little about the majority of species. Of 1,600 species in Canada examined, an estimated 65 percent were assessed as secure (not at risk, sensitive to risk, or needing more investigation) five percent were deemed at risk, and another five percent may be at risk but require a scientific assessment to confirm their status. British Columbia was identified as having the highest number of species at risk of all the provinces. However, BC also has a highly diverse biological landscape with a large number of species, and lower numbers of species that may be at risk but need investigation. Therefore, this higher at risk figure may be due to a higher proportion of investigation and classification of species in BC compared to other large provinces.

The reasons a species might decline or become at risk are complex and interrelated with a species' ability to survive in a given environment being affected both by external changes in its habitat as well as its ability to adapt to change and its own unique biological requirements. Despite the complexity a number of prevalent environmental influences are agreed to be leading causes of species decline:

Habitat Loss and Degradation – the expansion of the human population and development that goes along with it is responsible for a large share of measured species decline. When natural habitats shrink or are impacted by population growth species are gradually squeezed out. Even where a habitat is not destroyed, the impact of human activity can be sufficient to disturb breeding patterns, restrict migration, isolate groups of species and thereby limit gene pools, and suppress natural events such as floods and forest fires that maintain ecological diversity. It is estimated that 60% of species on the COSEWIC list are there because of threats to their habitat.

Environmental Contamination – even in areas where human activity does not directly impact or destroy habitats the impacts are still felt. Air, water and ground pollution all release chemicals and toxins into the environment which have impacts on wildlife. Such contamination is the second most important factor in measured species decline.

Over Harvesting and Excessive Trade – wild species taken for food, pelts, sport, or medicinal purposes, as well as removed from their natural environments as pets or for domestic cultivation. While no longer having the single largest impact on species populations, as was the case in the earlier part of the century, the impact of such activities on species survival still exists.

Climate Change – environmental change as well as cyclical temperature change to an ecosystem or extreme weather can impact species survival.

Disease – while natural in any ecosystem, disease in a species population may be more frequent and have a larger impact if that population is already in decline, limited in its range, or suffering from reduced genetic diversity.

Invasive Species – the introduction of species that are not naturally occurring in an ecosystem, often as a result of human activity for sport or agriculture reasons, can have a significant detrimental impact on native species.

COSEWIC lists 13 species that have gone extinct in Canada, including three found only in BC – the Dawson Caribou, and the Hadley Lake Benthic and Hadley Lake Limnetic Stickleback (fishes). In addition, the BC Government lists the Dragon Lake Whitefish as a BC-only species that is now extinct. In addition, six species are listed as extirpated in BC, meaning they are no longer found in the province but aren't globally extinct.

Sources: COSEWIC (2005), Canadian Species at Risk, and 500 Species Now Considered to Be At Risk; Janice Walton (2004), Endangered Species Protection Escalates in British Columbia, Mondaq; BC Ministry of Environment (2002), Species Ranking In British Columbia; Habitat Acquisition Trust website FAQ; Environment Canada, Why Do Some Species Become at Risk in Canada?; The Canadian Biodiversity Website, Human Activities and Their Impacts and Conservation Priorities; BC Ministry of Environment, What are The Threats to Species at Risk?; BC Ministry of Environment, Environmental Trends in British Columbia 2002 and BC Species and Ecosystem Explorer; Canadian Endangered Species Conservation Council, Wild Species 2000: The General Status of Species in Canada.
Note: an updated report, Wild Species 2005 is expected in 2006.