Least Tern

Find More Birds

Each map is a visual guide to where a particular bird species may find the climate conditions it needs to survive in the future. We call this the bird’s “climatic range.”

The colors indicate the season in which the bird may find suitable conditions— blue for winter, yellow for summer (breeding), and green for where they overlap (indicating their presence year-round).

The darker the shaded area, the more likely it is the bird species will find suitable climate conditions to survive there.


The outline of the approximate current range for each season remains fixed in each frame, allowing you to compare how the range will expand, contract, or shift in the future.


The first frame of the animation shows where the bird can find a suitable climate today (based on data from 2000). The next three frames predict where this bird’s suitable climate may shift in the future—one frame each for 2020, 2050, and 2080.

You can play or pause the animation with the orange button in the lower left, or select an individual frame to study by clicking on its year.

Climate Endangered

Least Tern

The darker the color, the more favorable the climate conditions are for survival. The outlined areas represent approximate current range for each season. More on reading these maps.

The darker the color, the more favorable the climate conditions are for survival. The outlined areas represent approximate current range for each season.

More on reading these maps.

Winter Range
Summer Range
Both Seasons
Zoom InOut
Focal Species
Flickr Creative Commons

The aptly named Least Tern—it’s really small—has been bedeviled for decades by habitat degradation. The species nests in the open near water, both coastally and along major inland rivers. Changing water levels, direct disturbance by humans, and development have diminished breeding populations. A new threat is climate change, with Audubon's climate model forecasting an 82 percent loss of current summer range by 2080. A silver lining in the cloud may be this tiny tern’s adaptability; the model shows some potential expansion into new regions of climatically favorable conditions, and active intervention by wildlife managers may permit the species to colonize new sites.


Are the projected range maps different from the range maps in field guides? Find the answer here.

Species Range Change from 2000 to 2080

The size of the circles roughly indicates the species’ range size in 2000 (left) and 2080 (right).

The amount of overlap between the 2000 circle and the 2080 circle indicates how stable the range will be geographically. Lots of overlap means the bird’s range doesn’t shift much. No overlap means the species will leave its current range entirely.

Birds at Risk

Explore more birds threatened by climate change around the country.

Allen's Hummingbird
Baird's Sparrow
Bald Eagle
Brown Pelican
Burrowing Owl
Cerulean Warbler
Common Loon
Eastern Whip-poor-will
Golden Eagle
Greater Sage-Grouse
Hooded Oriole
Mississippi Kite
Northern Shoveler
Piping Plover
Ruffed Grouse
Rufous Hummingbird
Spotted Owl
Tundra Swan
White-throated Sparrow
Yellow-billed Magpie

You Can Help

It's easier than you think to make a difference. Become an Audubon member today to help birds facing climate change.

Share Your Pledge

Thank you for pledging to help save the birds most at risk from global warming. But we need everyone’s help–and soon.

Share this urgent message with your friends and family. Tell them why these at-risk birds are so important to you, and ask them to pledge to do their part, too.

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