Scene Changes with Climate Change
Local plants and animals are changing with the climate, with new wildlife arriving while others move on, explains Josh Heath, Environmental Education Specialist
No travel needed to get a change of scene in the tri-state area. The scene here is changing both on the ground and in the air, says Josh Heath, Environmental Education Specialist at Pennsylvania Department of Conservation and Natural Resources. New birds populate the skies, as some find other places more habitable. Black Vultures, not seen here 15 years ago, now find the area appetizing, as road kill increases amid milder winters.
“They’re carrion eaters,” Heath said. “With less food available in winter, less pregnancies are completed, and fewer spring fawns are born. But when winters are warmer, there’s more browse, more food. And with suburban sprawl and human density, more deer and foxes adapt to it. They feed and sleep in small yards and parks with few natural predators around. The last decade of milder winters makes life easier for them too.”
Unfortunately for humans, ticks are also more likely to survive through warm winters, and with more large mammals nearby, travel is convenient for them.
“They use deer like a bus, They’re the largest warm-blooded animal in our ecosystem,” said Heath.
Plants that benefit from warmer winters include invasives such as the Japanese barberry and garlic mustard.
“They tolerate warmer winters better,” said Heath. “Garlic mustard likes roadsides and the margin between light and shade.”
Originally brought from Europe and Asia, garlic mustard germinates earlier than many native plants, interfering with their growth and the forest understory ecology, according to the Nature Conservancy.
Multi-flora rose, another invasive plant, was brought from Europe for medicinal purposes in the 1800’s, as it was used to cleanse the liver and kidneys, said Heath. But the plant can grow densely and displace native plants. Deer and rabbits lack the mouth structure to browse on it and also the invasive Japanese barberry, so those plants can grow unchallenged, Heath said. The Tree of Heaven, which grows fast in poor soil, also lacks predators.
Meanwhile, climate change has brought the emerald ash borer to the northeast, where it depletes ash trees. Following the loss of chestnut trees, the canopy is diminishing, allowing sun into the landscape, warming and drying it, said Heath. Consequently, the streams narrow, and as the ecology changes, amphibians and invertebrates need to find more suitable homes. Some birds are also inconvenienced.
“With ash seeds not there for turkey poults, partridges and ruffed grouse chicks, I don’t know what the long term effects will be,” said Heath. “Early seeds were big contributors to their diet before early grasses and berry bush fruit, though they eat grubs and insects.”
However, Canadian birds are newly appearing, like Yellow Bellied Sap Suckers and North Flickers.
“Maybe they’ll stay here all year, with climate change, if the temperature dips a half degree,” Heath said. “It depends on the insects they find when they probe the ground. They may compete with winter birds, who may then go further north.”
Meanwhile, geese migrate less, and half of their inhabitants in Promised Land State Park never left for the winter, he noted.
With milder winters, more rain and less snow and solid ice, Heath wonders whether evergreens will increase and whether natives or invasives will replace ash trees, as oaks tended to replace chestnut trees.
“Will red maples replace ash trees? I don’t know,” said Heath. “Emerald ash borer effects are just beginning to become clear, as are the effects of climate change.”