Without access to the surface, turtles' lungs aren't much use. (Parks Canada / Point Pelee National Park) The species is listed as of special concern in Canada. While adults can't survive subzero temperatures, hatchling use supercooling to prevent their bodies from freezing while overwintering in their nests. The northern map turtle can be found across southern Ontario, from Point Pelee National Park to Sudbury and Ottawa. The ultimate multi-tool, a turtle's cloaca has many functions, including excretion, urination, reproduction, egg laying and - in a pinch - oxygen uptake. "Essentially, in the winter time, they are breathing through their butts." This process is known as cloacal respiration.īut there's also a less scientific way to describe it, she added. Instead, they absorb oxygen from the water through several surfaces, including the cloaca - a specialized tissue located under their tails. Ontario's turtles spend the winter in frozen-over ponds, unable to surface for air, Charlton said. Six of those species can be found at Point Pelee National Park, including the endangered Blanding's turtle and spiny softshell turtle, said Julie Charlton, the resource conservation manager at Point Pelee in Essex County in southwestern Ontario. Ontario is home to eight freshwater turtle species. The species can be found across southern Ontario and as far north as Sudbury and Ottawa. Breeding and release programs in places like Point Pelee National Park are helping to restore populations. The Blanding's turtle is considered highly endangered in Canada. The sugar lowers the freezing point of the water in the blood and organs, and decreases the amount of water drawn out of the frog's cells, Storey explained.Īs a result, up to 70 per cent of the extracellular water in an overwintering wood frog can freeze without ice forming inside cells, leaving no trace of damage when they thaw in spring. They have way less ice than you would think at any given temperature because they have so much sugar." When temperatures drop to freezing, their organs start to shut down while the liver gets to work converting those stores into glucose. As a result, an overwintering wood frog's blood has 80 times more sugar in it than the average human's. So wood frogs spend the fall building up energy reserves. Similar to a deflating balloon, if too much water leaves the cell, the membrane starts to collapse inward.īut evolution has given wood frogs a way around this. You die of freezing by shrinking the cells down," Storey said. This starts a cycle where water keeps being pulled out of cells only to freeze, requiring more water to be drawn out. "Pure water freezes out as ice, leaving behind really concentrated blood, tries to balance itself by sucking the water out of your cells," Storey said. Yet every spring they come back to life again.įreezing every winter seems like an impossible life history - and for most animals it would be. WATCH | Check out this documentary on wood frogs from The Nature of Things:ĭuration 1:58 Featured VideoThese wood frogs are one of the only creatures that can be described as “the living dead”. Then they get dead during the winter - their life force seems to be going, and then they come back to life," said Ken Storey, a professor of biochemistry at Carleton University In Ottawa who has done extensive research on the wood frog. You'd think they were dead.īut then comes spring, and they start to thaw - from the inside out. They don't breathe and have no detectable brain activity. You've probably seen wood frogs in the summer, when they are a common sight across the country.īut when winter rolls around, they hide under leaf litter or just a few centimetres underground, where the temperature hovers a few degrees below zero. If you're fond of winter walks through forests in Ontario - and indeed most of Canada - odds are you've trod on a frozen frog. Monarchs and hummingbirds migrate thousands of kilometres, and bats and bears hibernate for months. But there are also animals that survive the winter in your own backyard, in ways you wouldn't expect. But Ontario wildlife have been enduring the cold for thousands of years. Surviving a Canadian winter can be a struggle - even with modern heating. Darius Mahdavi, a scientist with a degree in conservation biology and immunology and a minor in environmental biology from the University of Toronto, explains how issues related to climate change affect people across the province, and explores solutions, especially in smaller cities and communities. CBC's Great Lakes Climate Change Project is a joint initiative between CBC's Ontario stations to explore climate change from a provincial lens.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |