Global Warming and the Chesapeake Bay
The Chesapeake Bay is a national treasure for hunters, anglers, and outdoor enthusiasts. But this could be a paradise lost due to global warming, which poses a very real threat for fish and wildlife in the Chesapeake Bay region.
Over the past quarter century, billions of dollars have been invested in restoring the Chesapeake
Bay watershed. These major investments could be lost due to global warming.
Fish and wildlife are being affected by climate changes:
Warmer air and water will alter the composition of species that can live in the bay, contribute to worsening dead zones and harmful algal blooms, enhance marine diseases, and encourage expansion of harmful invasive species such as nutria.
Rapidly rising sea levels will inundate coastal marshes and other important habitats that are important for fish and waterfowl and make coastal property more vulnerable.
More-extreme weather events, including floods, storms, droughts, and heat waves will lead to more polluted runoff into the Chesapeake Bay, hurt water quality, and make the outdoor experience increasingly unacceptable for people.
Changing climate across North America will affect breeding grounds and migration patterns for
waterfowl, such that fewer birds make their way to Chesapeake Bay each year.
Solutions Are Available
Leadership at the federal, state and local level needs to:
- Reduce global warming pollution
- Better fund conservation activities
- Manage the land better in the face of global warming, by following best practices for land, stormwater and coastal management
Read in detail about these solutions by downloading National Wildlife Federation's Chesapeake Bay and Global Warming Report PDF (1.7 Mb file size)
Impacts on Wildlife
Note: These probable effects were identified based on available information, but significant
changes in key parameters such as temperature and salinity are likely to have wide-ranging
unpredictable effects on life cycles and food webs.
Some Featured Species Affected by Global Warming in the Chesapeake Bay
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Blue Crab - Fifty percent of the nation’s annual blue crab harvest comes from the Chesapeake Bay. Warmer winters could actually extend the growing season and lead to population increases, but eelgrass, which provides juvenile blue crabs with important habitat, would face significant danger if water temperatures exceed its tolerance levels.
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Canvasback - While canvasback populations for the past 50 years have been stable, the number of wintering canvasbacks in the Chesapeake Bay has declined from a high of nearly a quarter million birds in
the mid-20th century to an average of just over 30,000 birds in the last five years. This trend is due to due to a loss of
submerged aquatic vegetation and some birds not migrating as far south to find winter habitat. |
Climate is changing in the Chesapeake Bay region:
Average air temperatures in the region have increased by 1.4 degrees Fahrenheit along the coastal margins of the Chesapeake Bay through Maine over the past century, and much of the region has seen about a 10 percent increase in average precipitation, with greater precipitation extremes.
Average sea levels in the Chesapeake Bay have been rising. Many places along the bay have seen a one-foot
increase in relative sea-level rise over the 20th century, six inches due to global warming and another six inches due to naturally subsiding coastal lands — a factor that places the Chesapeake Bay region at particular risk.
Already, at least 13 islands in the bay have disappeared entirely, and many more are at
risk of being lost soon.
By the end of the 21st
century, the region could see an 8 to 15 percent increase in average precipitation compared to 2000.
Sea-level rise in the Chesapeake Bay region could reach 17 to 28 inches above 1990 levels by 2095.
Blackwater National Wildlife Refuge: A Chesapeake Bay Treasure
Blackwater National Wildlife Refuge is a crown jewel of the Chesapeake Bay. Located on Maryland’s
Eastern Shore, the refuge is home to a diverse and abundant collection of fish
and wildlife. Thousands of migrating ducks, geese, and swans use the refuge as
stopover and wintering areas, making it popular for hunting waterfowl. The wetlands help to control flooding and maintain water quality.
Sea-level rise is a major threat to the future of the Blackwater National Wildlife
Refuge. Since the late 1930s, sea-level rise and overgrazing by nutria have contributed
to a loss of one-third of the refuge’s coastal marshes. We must help Blackwater by confronting global warming and planning for sea-level rise.
