Climate Change at Home: Climate stressors taking toll on New England wildlife 

  • Chet Hall of the Bitzer State Fish Hatchery in Montague holds a net with brook trout next to one of the holding ponds. Wildlife experts say brook trout are a cold-water native fish struggling with climate change.  STAFF PHOTO/PAUL FRANZ

  • Brook trout are seen at the state fish hatchery in Montague. Experts say these native cold-water fish are struggling with climate change. STAFF PHOTO/PAUL FRANZ

  • A moose near downtown Greenfield.  STAFF FILE PHOTO/PAUL FRANZ

  • A 2- to 3-year-old, 700-pound female moose moves about Hillside Park off Conway Street in Greenfield in April 2016. Warmer temperatures in New England resulting from climate change will push moose further north, experts say, at the same time that it’s being blamed for the profusion of winter tick, which can kill calves with sheer numbers. TAFF FILE PHOTO/PAUL FRANZ

  • A young female moose wanders around the East Yard of the Rodney Hunt Co. in Orange center in April 2002. STAFF FILE PHOTO/PAUL FRANZ

  • Tom Lautzenheiser is a senior conservation ecologist for Mass Audubon. STAFF PHOTO/CAROL LOLLIS

  • Tom Lautzenheiser, a senior conservation ecologist for Mass Audubon, stands at a vernal pool at Arcadia in Easthampton. This time of year the water is usually higher and in the spring can get up to 4 feet high, but is low right now because of the summer drought. It is vital as a breeding ground for frogs, salamanders and other animals that live in the habitat. STAFF PHOTO/CAROL LOLLIS

  • Tom Lautzenheiser, a senior conservation ecologist for Mass Audubon, explains that a simple tulip tree seedling is a sign of climate change since Arcadia Wildlife Sanctuary is at its northern limits and seedlings would have a harder time surviving colder winters. “This is how our forest are changing with warmers winters a different variety of seedlings grow,” explained Lautzenheiser. STAFF PHOTO/CAROL LOLLIS

  • Mass Audubon conservation ecologist Tom Lautzenheiser looks for migrating birds at the Mill River at the Arcadia Wildlife Sanctuary marsh in Easthampton. STAFF PHOTO/CAROL LOLLIS

  • Tom Lautzenheiser, an senior conservation ecologist for Mass Audubon, stands in a wildlife blind looking over the Mill River at the Arcadia Wildlife Sanctuary marsh near the Oxbow of the Connecticut River in Easthampton.  STAFF PHOTO/CAROL LOLLIS

  • Tom Lautzenheiser, a senior conservation ecologist for Mass Audubon, talks about important habitat for migrating birds at the Mill River at the Arcadia Wildlife Sanctuary marsh near the Connecticut River Oxbow. STAFF PHOTO/CAROL LOLLIS

For the Gazette
Monday, November 21, 2022

New England has long been known for its four distinct seasons, but as climate change grips the region at a faster pace than many other parts of the world, this seasonal portrait is being reconfigured, and a variety of wildlife species are experiencing the consequences.

“Climate is a fundamental ecosystem characteristic and there are all kinds of effects that it can have on our wildlife,” says Tom Lautzenheiser, senior conservation ecologist for Mass Audubon.

How a changing climate impacts a given species depends on a variety of factors. These factors can include biology, physical adaptations, diet, reproductive strategies, and interactions with other species, including pests and pathogens, as well as the availability, size and quality of appropriate habitat.

Lautzenheiser said that generalist species, those that can take advantage of a variety of food sources and ecosystems, will fare better than specialist species that are adapted to very specific areas, foods, temperatures and environments.

For example, species with physiological adaptations to living in snowy and or cold conditions, migratory species dependent on seasonal timing, and specialist species that rely on narrow food and habitat resources will likely be the most negatively affected by warming temperatures.

Species such as black bear, coyote, fox, raccoon and other highly adaptable animals will not feel the climate pinch as much as temperatures rise and habitats change, wildlife experts say.

According to research ecologist Toni Morelli of the Northeast Climate Adaptation Science Center at UMass Amherst, New England is highly susceptible to climate change and is warming at a significantly faster rate than global averages.

Morelli says that seasonal patterns are changing, with earlier springs and long stretches of drought, followed by later falls with intense, flooding rains.

“This is what climate change is going to look like in the Northeast,” she said. “On average, we are getting wetter. But we don’t live in averages, we will live in these extremes, and that goes for the wildlife, too.”

Climate projections show that by the end of the century, the region will not have snow through most of the year, Morelli notes. “That is a huge shift for animals that depend on snow,” she said.

Thermal stress, mismatches in seasonal synchronicity, and habitat destruction is affecting wildlife from the forests to the seacoast and ocean environment, as climate change forces wildlife species to adapt, shift their ranges, or eventually succumb to a warming environment that can no longer support their needs.

Some New England species are standout examples of the effects of climate change, and how they can interact with existing stressors.

“One of the most striking stories is what is happening with the moose in Maine and New Hampshire,” Morelli said.

Here, climate change has delivered a one-two punch to this large, long-legged, heavy coated boreal species by creating an inhospitably warm environment while giving rise to a parasite that is decimating its numbers.

“Moose are having a particularly hard time because of winter tick,” Morelli said, noting that infestations of over 80,000 ticks have been found on individual moose. These numbers can drain the blood out of calves over the winter. Surveys reveal that last year, there was a roughly 80% mortality rate of moose calves in Maine and New Hampshire.

Morelli says that moose in Massachusetts are not affected by winter tick, likely due to lower moose population densities, which deny the tick an abundant host.

Still, the climate-induced rise of parasitic pests is not the only problem. Moose have a physiological limit to temperature and begin to experience heat stress at summer temperatures above 57 degrees and winter temperatures above 23 degrees.

“Now with warmer temperatures, they are not going to be able to handle the weather we are anticipating we will have,” Lautzenheiser said. “They will eventually get pushed out, separate from the tick issue.”

Like the moose, snowshoe hare are well adapted to live in snowy environments. A master of seasonal camouflage, their summer brown coat molts to white during the winter. While the change is triggered by changes in day length, the color of the coat is genetically determined, leaving the hare mismatched in a snowless environment, making it an easy target for predators.

The Canada lynx also is uniquely adapted to living in cold, snowy environments with its long legs, large paws and thick coat. While a decrease in snow cover limits lynx habitat, its survival is also closely linked to the snowshoe hare, which comprises roughly 96% of its diet.

Morelli says a lack of snow also will affect some hibernating and ground burrowing animals as they will lose the snows’ insulating effect.

“Snowless winters actually mean really cold ground and these species experience much colder environments because of no snow,” she said.

Colder ground means that hibernating animals will have to use more of their fat stores to stay warm, further depleting them of insulation.

Some aquatic species are also struggling through warming and dry conditions.

“Brook trout are the poster child of cold-water native fish struggling with climate change,” Lautzenheiser said.

Brook trout generally cannot tolerate extended periods of water temperatures above 68 degrees. Because these fish depend on highly oxygenated cold water to survive, their populations have been greatly reduced due to rising temperatures and reduced stream flow.

Climate change is also taking a big toll on amphibians dependent on vernal pools, unique seasonal pools of water that provide habitat for distinctive plants and animals.

“Vernal pools host a number of frog and salamanders that are obligated to breed in those fishless environments,” he said.

However, warmer temperatures and changes in precipitation patterns can cause vernal pools to dry out too quickly for these species to complete their breeding cycles.

“This could really be a problem for a lot of specialist animals like spotted salamanders and marbled salamanders,” he said.

Like the moose with winter tick, amphibians also have an additional parasitic stressor.

“Herps are in trouble around the world,” Morelli said, referring to herptiles, or reptiles and amphibians. “We are worried about frogs and salamanders in the Northeast because of diseases like chytrid,” she said.

Chytrid is a fungus that ravages the skin of frogs, toads and other amphibians, eventually killing them.

On the coast, rising sea levels are inundating salt marshes and beaches, threatening species including the saltmarsh sparrow and piping plover.

Piping plovers build nests in the narrow section of land between the high tide line and the foot of coastal dunes, and saltmarsh sparrows nest exclusively in a narrow band of tidal marsh that extends from Maine to Virginia, with up to half of the global population breeding in southern New England.

“Oceans are also experiencing these major shifts and certainly wildlife is responding to that,” Lautzenheiser said. “We are seeing essentially wholesale shifts in fish and sea life ranges.”

According to the National Oceanic and Atmospheric Administration, the Northeast has warmed more than any other region in the Lower 48 states, passing the U.N. threshold of 2 degrees Celsius of warming. The general hypothesis for this is that warming waters in the Atlantic Ocean are contributing to warming in coastal and inland areas of the Northeast.

“When the global mean temperature is up 2 degrees, here in the Northeast we will be up 3 degrees,” Morelli said.

Land conservation efforts are one area that could provide some relief for species threatened by a warming climate.

As scientists study the current impact of climate change on wildlife, they say that climate change refugia, or the conservation of areas that might remain relatively buffered from contemporary climate change, may help some species over time.

“There has been a huge increase in the human population over the last century and a huge increase in concrete, invasive plants and insects, changes in temperature and changes in precipitation,” Morelli said. “If there are ways in which conservation can reduce some of those stressors, then species that have been around for millions of years and adapted and evolved to threats can potentially respond to current threats and manage to adapt.”