The Register Citizen (Torrington, CT)
Experts: Frogs emerging early a sign of climate change
About a week into March, University of Connecticut ecology professor Kurt Schwenk heard something disturbing at his home. The pond across the street had erupted in frog song. Wood frogs, who normally emerge at the end of the month, had awoken from dormancy roughly three weeks early.
“The feeling was a little like (the horror film) Poltergeist, you know — ‘they're here' — it's a scary thing, not a good thing,” Schwenk said.
He isn't alone. Scientists and naturalists have noted unseasonable behavior in many animals. Reptiles and frogs, because they are cold-blooded, happen to be particularly sensitive to these changes.
“Anyone who is in tune with aspects of nature starts to notice these things,” Schwenk said. “When they start going off (earlier than usual), I find it frightening because it implies a lot. It opens the door to a lot of questions we don't know the answers to.”
The early frog song is a hallmark of a year that has gotten off to an unseasonably warm start. While there have been record one-day snowfalls, the weather overall this winter has been warm enough to keep us brown and
muddy for much of the season.
Recently, the National Oceanographic and Atmospheric Administration announced that the nation had experienced the warmest winter on record. February of 2024 was the third warmest February ever recorded. This is just one of the many climate change superlatives that have come in cycles over the past 10 years. As the climate warms, headlines routinely announce the hottest, most extreme, or largest weather events now occurring. From wildfire smoke days to extreme rain, everyone is feeling the effects of climate change.
Despite this, many Connecticut
residents don't think climate change has affected them personally. Survey data collected by the Yale Program on Climate Change Communication indicates that while the majority of nutmeggers believe that climate change will happen, or is already happening, they haven't personally experienced it. According to Yale's latest survey, roughly 69 percent of the state thinks that climate change is affecting the weather but only 47 percent think they have personally felt the effects.
Last “summer was off the charts in so many ways beyond expectations,” said Jennifer Marlon, a research scientist at Yale who studies wildfire, climate
change and public perception. “As we were making these opinion maps it was shocking to see that it did not seem to be registering in Connecticut and beyond.”
Marlon said the reason people weren't linking climate change to their own lives is complicated. Most people tend to be biased toward optimism, assuming bad things won't necessarily happen to them, she said. As a result, information about climate change tends to be isolated from mainstream conversations.
“They're just not getting a lot of environmental news on a day-to-day basis,” said Marlon. “One event happens, people say ‘wow that's scary' but then they kind of forget about it and move on.”
But for people who closely track the natural world, climate change is here and it's already affecting animal behavior. Schwenk said he had been noting that reptiles and amphibians are coming out of dormancy earlier and earlier over the past decade. These animals bury themselves in burrows over-winter, he said. When the ground gets
warmer, they move closer to the surface to wait for the final transition to spring. If the weather turns spring-like, they awaken and emerge.
“Based on the behavior of reptiles and amphibians we're seeing that a lot of the emergence behavior must be ruled by temperature,” said Schwenk, adding that if they were cueing in to the length of the day, which hasn't changed, then reptile and amphibian behavior probably wouldn't be so erratic in warming winters.
Mark Lotterhand, a wildlife photographer and naturalist who has extensively documented the lifecycles of endangered reptiles in New England, said lack of snow cover on the ground is exacerbating the trend.
“If snow is hard-packed over them in the woods I've never witnessed them break through the snow,” Lotterhand said. Beyond the physical barrier the snow provides, it also keeps the ground colder longer, delaying spring awakenings.
Lotterhand has trail cameras set up at eastern timber rattlesnake nests and routinely goes into the forest during all seasons on photo expeditions. He said his cameras have captured rattlesnakes basking in the sun on Christmas and frogs popping their heads through thin, late-winter ice.
“One warm day, historically, it's not going to affect the overall microclimate. It's not like you have one warm day and the snakes come out,” said Lotterhand. “It takes weeks of the ground not being cold.”
Scientists say that it's not just about animals behaving strangely, but rather as the climate warms, it brings changes on an ecosystem-wide level. That affects everything from agriculture to when the wood frogs start singing. Schwenk said the overall future effect of these cascading changes is unclear, but the problem is much larger than just frogs. Frogs emerge when they do so they can time their next generation with the spring spike in insect population. Insects emerge when plants leaf and flower to eat and pollinate. It's all connected.
“The moment these things start getting out of sync, everybody's screwed, you've broken the food web,” Schwenk said. “The danger isn't just not to any one group; the danger is the whole system breaking down because of this lack of synchrony.”
Lotterhand said early frog song is really “another canary in the coal mine” for escalating and unstable changes in the climate that will, inevitably, affect everything and everyone.
Most people may not care about frogs, but it's a huge data point, Lotterhand said. “You connect all the data points, whether that's more hurricanes or fires … it's just another screaming example of climate change happening.”