Snakebites: Canada will be dealing with more of them in the future.
A new study provides detailed projections on how snake populations in the Americas will be on the move over the next three decades, thanks to global warming, and forecasts the growing risks of snakebite in various regions of North, Central and South America.
“This study presents the first attempt to model current and future snakebite risk on a hemisphere basis,” say the study’s authors, researchers at the Biodiversity Institute at the University of Kansas. “According to our future projections, we forecast an expansion of snakebite risk areas northward in Canada and southward in Argentina and Chile.”
An estimated 300,000 snakebites occur annually in the Americas, resulting in somewhere between 650 and 3500 deaths. The vast majority (approximately 90 per cent) of the bites occur in the tropical regions of Latin America where snakebite is an occupational hazard for agricultural workers in rural areas.
In the United States an estimated 9000 people are treated for snakebite each year, with about five dying from their injuries.
In Canada the numbers are even lower, with an estimated 300 people getting bitten each year and none dying from the bite.
In 2007 the World Health Organization categorized snakebite as a “neglected tropical disease,” with an estimate of between 20,000 and 90,000 deaths worldwide each year, the highest concentrations being in South and Southeast Asia and Sub-Saharan Africa.
The study used geographic information systems (GIS) and incidence data to identify regions of high vulnerability to snakebite, along with modelings of regional climates in the Americas for the year 2050 based on current projections for temperature increases.
The researchers found that the regions in which snakebite risk is about to increase most prominently include Central America, the northern part of South America, Mexico and the southern U.S., whereas countries like Canada and Chile which currently do not have a great risk of snakebite will see new species entering their regions.
Researchers project that depending on the species of snake, the changing climatic conditions will either prove beneficial or harmful. Some such as the flat-nosed rattlesnake and the jararaca will see their territories expand northward and southward from Mexico and Central America while others such as the crossed pit viper and South American rattlesnake will find fewer areas with suitable habitat conditions.
In an interview with Torstar News Service, A. Townsend Peterson, professor of ecology and evolutionary biology at the University of Kansas and study co-author, sounded a word of caution for Canadians, saying that only a few new species will spread into Canada and those that do are classified as low risk, meaning that they’re less likely to be confronting and biting people.
Changes to snake populations and snake species are not just projections for the future but have in fact been already recorded across the Americas. Of the snake species whose populations are themselves at risk due to disruptions in their habitats,
Dr. Peterson says that some may fail to adapt and become extinct. “Will they be gone by 2050? We don’t know. It’s like being on death row.”
A recent study found that snakes are the top fear of both male and female Canadians, with 33 per cent of men and 46 per cent of women fearing them.
The research was published this month in the journal Climatic Change.