Hello! I’ve been working with Wildlife Preservation Canada to help recover one of Canada’s most endangered snakes – the blue racer.
The blue racer is one of Canada’s most endangered snakes. The species once occupied several locations in Ontario, ranging from Pinery Provincial Park down to Point Pelee National Park and Pelee Island. However, since the early 1980’s, these magnificent snakes may only be found on Pelee Island in the western basin of Lake Erie, where a single population remains. They were listed as endangered in 1991 and extirpated from the mainland. Supported by WPC and several partner organizations, including Nature Conservancy of Canada, Ontario Nature, Queen’s University, Scales Nature Park, Natural Resource Solutions Inc., I recently completed my Masters of Science (MSc) Degree at the University of Toronto studying the blue racer. My MSc is part of a large and highly collaborative three-year research and outreach project geared towards the conservation of the species.
One of the main goals of the project is to estimate how many blue racers are left in Canada, known as their abundance. Twenty years have passed since the last estimate of approximately 141 (95% confidence interval = 59.0–284.7) mature adults was produced for the species, and it was identified that this number was on the decline. With an extremely small and declining population, the blue racer continued to meet the criteria for being classified as an endangered species.
However, the current status of the population is completely unknown. Are they almost extirpated? Has their decline slowed? This is the information the project was designed to uncover.
From 2020 to 2022, every spring and fall, a dedicated team of 6-8 biologists head out to Pelee Island for up to 5 weeks at a time. They spend every sunny day visually searching for the elusive blue and grey snakes, diving into tall grasses, shrubs, and poison ivy to catch them. The capture of these snakes is critical to the production of an abundance estimate. Upon capture, a snake is scanned for a Passive Integrated Transponder (or “PIT”) tag. If the individual has one, it means that the snake has been captured before and will be recorded as a recapture. If the individual does not have a tag, it will be fitted with one and recorded as a new capture. The number of new captures and recaptures of blue racers throughout the project will be the data that is used to produce an estimate of abundance through capture-mark-recapture analyses.
As it stands today, the blue racer research team has completed over half of their surveys and have tagged more than 100 snakes! Though we do not presently have enough data to accurately estimate population size, there are some extrapolations that can be made from our capture numbers to date.
Most excitingly, the blue racer is doing better than anticipated!
From the previous estimate, indicating a population of approximately 141 snakes and declining, capturing over 100 individuals in the first two years of the project is a promising sign that the population may not have declined much further over the past two decades.
WPC and the survey team are excited for our final year of snake surveys in 2022, and for the analyses and results that follow. Attaining an understanding of how many blue racers are left in Canada will fill a crucial knowledge gap for the species and establish a baseline for their immediate and future conservation needs.