The Canadian frog conundrum

Many of us might not think of Canada as a good place to live if you’re cold-blooded. Nonetheless, Canada is home to a wide variety of amphibian and reptile species. Figuring out how they can live their lives amongst cities and farms is a conundrum for conservation scientists.

Modern amphibians and reptiles are the oldest group of terrestrial vertebrates still walking the planet. They include creatures such as frogs and toads, snakes, lizards, turtles and crocodiles. Many of these are associated with wetlands and other aquatic environments.

However, the long reign of amphibians and reptiles is starting to look shaky. Across the world numbers are dropping and species are disappearing. Since 2000, 37 species were confirmed extinct*. In Canada the statistics even are worse than the international figures with more than 42% of amphibian and 77% of reptile species currently diagnosed as at-risk*.

The Wood frog (Rana clamitans melanota) doing its bit for survival of the species. Photo by: Cephas

The Wood frog (Rana clamitans melanota) doing its bit for survival of the species. Photo by: Cephas

So what’s causing these creatures to disappear? The most serious threat in northern Canada is habitat loss and fragmentation. Threats to habitat include “water management” for some species – in other words building dams, draining wetlands and the like. The key driving force here is not urban, but agricultural development.

In high latitude countries like Canada, many species are at the edge of their distribution. It is thought these peripheral populations may exhibit greater sensitivity to environmental changes because of reduced genetic variability. On the flipside of the coin Canada’s amphibians and reptiles are most diverse and abundant in the southern part of the country where the climate is warmest, but where most people live and grow their food.

Modified agricultural landscapes like this in Alberta Canada are contributing to the decline of amphibians and reptiles. Photo by: WinterE229 WinterforceMedia

Modified agricultural landscapes like this in Alberta Canada are contributing to the decline of amphibians and reptiles. Photo by: WinterE229 WinterforceMedia

One of the key tools available to protect endangered and threatened biota, like amphibians and reptiles are various pieces of legislation. Such legislation is typically complex and must represent a workable compromise between conserving wildlife and safeguarding the legitimate interests of landowners and other stakeholders.

Traditionally legislation has focused on rare species, based on the assumption that these are in greater jeopardy than common and widespread species. However common species contribute more to ecosystem function than do rare, spatially-confined species. One way scientists and managers are re-thinking conservation is to protect common or ‘‘keystone’’ species, thus simultaneously helping to protect ecosystems and other rare or at-risk species that depend on common species.

Canada has many parallels with Australia in how they are dealing with declining species. A focus on economic growth has contributed to diminished science funding, diluted protection of aquatic ecosystems, ‘‘streamlined’’ environmental impact assessment criteria, and increased uncertainty around the future of species-at-risk acts and regulations.

A snapping turtle searching for a place to lay eggs (Killarney National Park, Ontario). Photo by S. Linke.

A snapping turtle searching for a place to lay eggs (Killarney National Park, Ontario). Photo by S. Linke.

So the next time you hear governments celebrating “cutting green tape” its worth remembering why these regulations were set up in the first place and that we might be cutting more than we bargained for.

*The full article on which this post is based is:

Conservation of herpetofauna in northern landscapes: Threats and challenges from a Canadian perspective. By D. Lesbarrères, S.L. Ashpole,, C.A. Bishop, , G. Blouin-Demers, R.J. Brooks, P. Echaubard, P. Govindarajulu, D.M. Green, S.J. Hecnar, T,Herman, J. Houlahan, J.D. Litzgus, M.J. Mazerolle, C.A. Paszkowski, P. Rutherford, D.M. Schock, K.B. Storey, and S.C. Lougheed, Biological Conservation 2014, 170, 48–55.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

w

Connecting to %s