Wildlife and Climate Change

NPS Photo / Graphic by 4C

Climate change has produced a number of threats to wildlife throughout our parks. Rising temperatures lower many species survival rates due to changes that lead to less food, less successful reproduction, and interfering with the environment for native wildlife. These detrimental changes are already apparent in our National Capital Area parks.

Rising Temperatures and Invasive Species

Rising temperatures risk destabilizing the balance between wildlife and their ecosystem. As plants adapt to changing warming patterns, usually by blooming earlier or shifting to cooler locations, the wildlife that has adapted to them will be forced to face new environments.

Some species will struggle to find nutritious enough food to fit their existing gut biomes. Pollinators, for example, must feed from flowers that are blooming earlier in the year. Other animals may find their habitats are no longer able to support their biology.

However, it is also possible that some animals will do better in a warmer climate. Those species will outcompete others, expanding their own territory and food sources. But not all wildlife belong where they flourish. When species adapted to their environments lose their natural advantages, that leaves room for invasive species to multiply in the changing environment. Emerald Ash Borers and Gypsy Moths are examples of invasive species commonly found in the National Capital Region that have devastated native communities.

Big Hunting Creek at Catoctin Mountain Park

Photo by Kent Walters

Native Brook Trout at Risk

Brook trout in the Catoctin Mountain Park offer a clear example of how climate change effects interact with invasive species spread. The brook trout is a freshwater fish species native to eastern North America, and it requires cold, clear stream habitats. Competing with the brook trout are nonnative brown trout which can tolerate higher temperatures.

Increases in air temperature are warming aquatic habitats, leading to an overall decrease in brook trout and giving the survival advantage to the invasive brown trout. A 2017 study from the US Geological Survey found that brook trout are capable of adapting and foraging for food in warmer waters but not when they’re competing against brown trout.

Flooding and Loss of Habitats

Increased precipitation from climate change is contributing to more frequent and extreme weather events such as flooding. The higher frequency of flooding has detrimental effects on wildlife because they can destroy key pieces of ecosystems and habitats.

There is the obvious destructive effect that floods have on the environment—such as flooded land and burned forests—but they also have other lasting effects like severe water pollution. Speedy flood waters spend little time in a purification place (like in the ground or in a wetland) so the surface flow doesn’t lose the soil particulates pollutants it has picked up. Their speed also erodes streambanks and soil surface. New locations of standing water can drown tree roots, too.

Rock Creek Park provides critical nesting habitat for the wood thrush, DC's bird.

NPS Photo

Wood Thrush Migration

The wood thrush is the official bird of Washington, DC, and can be found in Rock Creek Park, but changes in climate may eliminate their regional population within the century. In addition to altering this songbird’s DC habitat and food sources, climate change negatively interferes with the wood thrush’s lengthy migration from Central America.

Wood thrushes fly up from the tropical forests of Central America every summer to their northern breeding grounds, anywhere from Florida to Maine. They need dependable ripe fruit and insect populations to fuel their journey, which may not be available as the climate warms. Furthermore, their usual breeding grounds are growing warmer, meaning they lose habitable areas and must fly farther north.

What Can You Do?

Though climate change has and will continue to hurt wildlife in many ways, there are multiple efforts to mitigate its effects. The National Park Service is taking steps to prepare for and reduce the detrimental effects of climate change, and everyone who visits can take meaningful steps to help.

NPS Photo / Graphic by 4C