Environmental Trends 2007

Species Conservation

Most of the 809 non-native species recorded in B.C. in 2007 are plants.

Species Group	Number of non-native species	Percentage of all species in the group
Vascular plants	730	23.7 %
Molluscs (non-marine)	32	18.6%
Birds	16	4.1%
Fish, freshwater	14	13.5%
Mammals, terrestrial	11	8.4%
Amphibians	2	9.1%
Butterflies	2	0.9%
Reptiles & turtles	2	10.5%
Total	809	19.1%

Non-native organisms (also known as ‘alien’ or ‘exotic’) live outside their natural range usually because they have been deliberately or accidentally introduced there by humans. About 10 per cent of non-native species become invasive, causing ecological damage and economic losses.
Provincial regions with the greatest increase in distribution of non-native species are those with the largest human population: Vancouver Island, Lower Mainland, Okanagan, and Kootenays.

The number of non-native plant species in B.C. has increased by 29 per cent since 1994.

Some of the 713 species of non-native plants established in B.C. have become a serious problem. About 65 per cent of these species appear to be widely distributed, likely because they were imported with livestock feed or introduced through nurseries. Many of the most invasive plants -- Scotch broom, purple loosestrife, baby’s breath, Japanese knotweed--have escaped from gardens.
The number of non-native freshwater fish went up from 7 species in 1950 to 18 in 2005. As of 2005, 860 water bodies in B.C. were known to be inhabited by at least one non-native species of freshwater fish.
The provincial tracking system records 45 species of non-native vertebrates and 34 species of invertebrates (including insects), but the actual number is very likely to be higher. Ballast water in cargo ships, for example, may contain thousands of tiny organisms.
Left uncontrolled, some non-native species degrade ecosystems and threaten commercial industries. Of particular concern are the Asian gypsy moth, which threatens forestry and nursery sectors, and, the fungus ‘sudden oak death’, which can infect many nursery and native plant species.
Since the 1950s the B.C. Ministry of Forests and Range has been releasing biological control organisms to feed on invasive plants. Over 70 species of biocontrol agents – mostly insects – have been released in the province to target 27 plants including St. John’s wort, spotted knapweed and diffuse knapweed, tansy ragwort, and leafy spurge.

For detailed information, including graph data, see In-Depth Report [pdf].