Climate Corner: Bye-bye, birdies

May 18, 2024

Linda Eve Seth

editorial@newsandsentinel.com

“Birds tell us about the health of our natural environment — we ignore their messages at our peril.” — Patricia Zurita, BirdLife CEO

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Bird populations are declining around the world. While many factors contribute — from habitat loss to pesticides, threats posed by agricultural machinery and harmful chemicals used in farming, outdoor cats and window collisions — it is increasingly clear that climate change is an important factor behind this concerning trend.

A 2022 report found that worldwide 49% of bird species are in decline, and one in eight are at risk of extinction, while only 6% of bird species are increasing in numbers. Warblers, red-headed woodpeckers and certain owls are a few of the North American bird species projected to be threatened by climate change in the coming decades, according to recent research.

Climate change affects birds both directly and indirectly.

Warming temperatures are changing where birds live, the timing of their migration patterns and egg laying, and even the sizes and shapes of their bodies. Increased temperatures due to climate change may directly affect birds by forcing them to use more energy for thermoregulation.

Two-thirds of North American birds are in danger of extinction from climate change, according to a study cited by Audubon Magazine in 2020. It was found that the ranges of many resident (year-round) species in eastern North America are staying put, while migratory birds are breeding farther and farther north over time. Migratory species are also shifting the timing of their annual movements, arriving in North America in springtime about two days earlier each decade since the 1990s. It adds up.

Too much precipitation is an additional concern, Both the increasing amounts of rainfall that are predicted during the breeding season, and days of extreme heat threaten the reproductive success of songbirds.

If climatic conditions of their living environment become too hot or too cold, or too wet or too dry due to changes sparked by climate change, birds may have difficulty adapting quick enough to survive within their natural range. Distributions are changing. Bird populations are expected to shift poleward, or to higher elevations, to stay with their ideal temperatures as the climate changes. In mountainous areas, birds also have the option of moving uphill instead of north. But these species risk running out of elevational options eventually as temperatures continue to warm. Depending upon the climate change scenario, many North American birds simply won’t have enough suitable habitat left to move into in the decades to come.

In addition to the direct effects that living in a warming world have on their lives and bodies, birds also face a tangled web of indirect effects, as the ecosystems in which they live are increasingly disrupted. These include:

* DROUGHT AND FIRE: More intense droughts and increasingly frequent wildfires can alter and destroy nesting areas and habitat upon which vulnerable bird species rely. Intense storms and increased rainfall are also affecting avian ecosystems.

* SEA-LEVEL RISE: Along the U.S. East Coast, as sea levels move upward, the nests built in marsh grass are increasingly being drowned by high tides, the birds who nest in the narrow strip of wetlands between land and sea at risk of extinction.

* DISEASE: Drought and warmer temperatures are causing a spread in West Nile virus across more of the United States, threatening wild birds. Drought leads birds to congregate in large numbers around water sources and stresses their immune systems, making them more vulnerable to the mosquito-borne infection.

Climate patterns have shifted throughout Earth’s long history, and over time, the flora and fauna of Earth have mostly adapted, but the speed of climate change in recent decades is unprecedented, making it more difficult for birds to adapt.

It has been decades since a whippoorwill’s plaintive call has been heard in our hollow, and 10 years since we heard an evening chat sing its spirited tunes in the maple tree in our yard. But if we take action now, by stabilizing carbon emissions and holding warming to 1.5°C above pre-industrial levels, we can improve the chances for hundreds of bird species. Seventy-six percent of vulnerable species will be better off, and nearly 150 species would no longer be vulnerable to extinction from climate change.

Until next time, be kind to your Mother Earth.

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Linda Eve Seth, M.Ed. SLP, is a mother, grandmother, concerned citizen and member of Mid-Ohio Valley Climate Action.