Invasive Species

Species Are Spreading Like Never Before

Plants and animals are expanding their ranges farther and faster these days than ever before in the planet's history.

What Makes a Successful Invader?

Only a handful of factors always influence whether a plant or animal successfully moves into territory outside its native range.

Global Trade Spreads Invasive Species

The biggest influence on how many destructive exotic species a country has acquired is the amount of international trade it's involved in.

Invasive Species For Sale at Local Stores

Gardeners and pet owners might inadvertently release new invasive species into the environment, an investigation of plant and pet stores discovers.

Animals

Islands Rescued From Invasive Rats

Huge gains have been made over the last twenty years in stopping invasive rats and mice from destroying island biodiversity.

An Intruder Among Rare Relicts

For the first time, seal salamanders were discovered in 2003 on the Ozark Plateau in northwest Arkansas.

European Lizard Firmly Established on Vancouver Island

Common wall lizards, native to Europe, now thrive abundantly on southern Vancouver Island after a few were let loose at west Sannich in 1970.

Eastern Squirrels Released into BC Suburbs

Since 1970, eastern grey squirrels have expanded their turf in British Columbia from a few hectares in Stanley Park to throughout the Lower Mainland, including Langley and Maple Ridge.

Plants

Deer Rapidly Spread Invasive Plants

A surprisingly large quantity and variety of plant seeds are getting carried substantial distances by white-tailed deer.

The Same Plants Are Showing Up Everywhere

North America's plant life is becoming increasingly uniform throughout the continent.

Chemical Arsenal Helps Plants Invade

Biologists probing the question of why some exotic plants can quickly populate a continent have uncovered another characteristic of successful invaders.

Invasive Tree Adapts to New Habitat

Chinese tallow trees, after being introduced to the southern United States, have evolved in North America to outgrow tallow trees in their native Asian habitat.

Unusually Flexible Super-Genes Discovered

Scientists have dubbed the DNA complement of fountain grass a "super-genotype" because the genes function like no others yet encountered.

Aquatic Species

Aquarium Fish Poised to Invade Lakes

People dumping their pet fish into local waterways could introduce yet another exotic species into the Great Lakes watershed.

Ships and Aquaculture Blamed For Spreading Species

Invasive marine organisms now inhabit nearly all coastal areas.

Rainbow Smelt Decimate Walleye Stocks

Data now confirm that walleye stocks plummet after rainbow smelt move into a lake.

Rare Alga Morphs Into Widespread Nuisance

A once rare and innocuous freshwater alga seems to have recently mutated into an amazing menace.

Escaped Fish Destroy Native Ecology

Out of the 3072 reported incidents of fish getting loose into a foreign ecosystem, 60% have founded wild populations.

Gluttonous Snails Threaten Farms and Ecosystems

Aquarium enthusiasts have often marvelled at the voracious and undiscriminating appetites of their pet apple snails.

Exotic Species Endanger Native Fish

Non-native fish are already implicated in the extinctions of five fish species in Canada and they threaten the continued existence of many others.

Ships Release New Species into the Great Lakes

Analysis of ballast water recently carried by ships into the Great Lakes indicates that more exotic species will likely invade the freshwater ecosystem.

Tenacious Sea Squirt Invades North American Waters

Scientists warn that an aggressive sea squirt could wreak ecological havoc to marine environments and economically harm the aquaculture and fishing industries.

Chinook Salmon Rapidly Colonize Rivers

It's taken less than thirty years for chinook salmon that were let loose in South America to establish spawning runs along 1500 kilometres of the South Pacific coast.

Insects

Abrupt Change in Mix of Ladybug Species

The assortment of ladybug species living in North America has shifted dramatically in the last 20 years.

Hemlocks Could Disappear From New England Forests

Eastern hemlock trees might be gone from New England forests by the end of the century, thanks to an introduced insect and warming climate.

An Invasive Species Helps Another Attack Hemlocks

Instead of one invasive insect out-competing the other, as researchers expected, hemlock woolly adelgid appears to be helping the elongate hemlock scale infest trees in the northeastern United States.

Invasion of Cutworm Moths Will Cause Economic Damage

Two cutworm moth species, recently introduced to British Columbia from Eurasia, are about to become economic pests throughout the province.

Diseases

Some Birds Highly Susceptible to West Nile Virus

West Nile Virus has decimated populations of some North American bird species, while sparing others.

Rocky Mountains Losing Whitebark Pine

A fungus introduced from Europe is well on its way to rendering whitebark pine trees extinct in some North American national parks, scientists warn.