What happens to cold-blooded wildlife in cold climates?
The entire country is bracing for record low temperatures this week as the winter solstice has come and gone. While most northern states are over the worst of their conditions, some southern states are still waiting winter storm elliott beat. Temperatures in the Deep South are expected to dip into the teens Thursday night, which could spell disaster for fish, reptiles, and amphibians. In fact, such conditions are so bad for cold-blooded creatures that they actually pose a threat to the safety of humans, too: Miami National Weather Office issued a public warning for cold-stunned iguanas falling from trees in Florida in 2020 and 2021.
What are you supposed to do when an iguana falls out of your tree? Well, since the species are not native, the Florida Fish and Wildlife Commission Tell us this is actually a good time to remove the pesky creatures. But no matter what, the FWC warns, never bring them into your home, as they could cause a little chaos once they thaw.
Other cold-blooded species have managed to hone their survival skills in frigid climates over the years. alligators are known to bury themselves on the banks of rivers and ponds, where their body heat insulates the space around them. Sometimes they even stick their snouts out of the water and let ice form around them. This allows them to keep breathing while they wait for the weather.
Frogs hang out at the bottom of bodies of water to hibernate during the colder months. In especially cold cases, their bodies freeze and they will even stop breathing. In this state, they rely on their livers producing enough glucose to prevent their organs from filling up with ice crystals. Up to 70 percent of the water in a frog’s body can freeze without the frog dying.
Unfortunately, other wildlife species are not as well evolved or lucky when it comes to cold weather. As of March 2021, Texas Parks and Wildlife officials estimated that at least 3.8 million saltwater fish (mainly speckled trout and redfish) died during winter storm Uri. With inshore water temperatures dropping to the 40s in many of the shallow bays and back lakes, many of the fish were unable to reach deeper water fast enough.
sea turtles suffer a similar fate during inescapable cold snaps. They are dazed from the cold and cannot swim or fend for themselves against predators. They usually wash up on beaches, where they have a small chance of thawing or being rescued.
These low temperatures come shortly after the southern states endured record heat in early December. These large changes can interfere with migratory wildlife and aquatic species that time their departures to warmer regions based on climatic conditions. The late heat tricks them into staying longer in their summer range, putting them at risk of being in the wrong place when these snaps of extreme cold hit. Weather extremes are just one example of how climate change affects wildlife around the world.
The situation is not much better for some warm-blooded marine mammals. Although they are much better at regulating their temperature and adapting to their environment, some can still become hypothermic. In 2010, 244 endangered manatees died during a cold snap in Florida waters.