It’s Hot! Extreme Heat and Our Birds

Summary: It is hot, hot, hot! How do birds deal with the increasing heat we’re currently experiencing? Join Cheryl and Kiersten as they talk about how birds keep cool in the summer heat.

 

For our hearing-impaired listeners, a transcript of this podcast follows the show notes on Podbean.

 

Show Notes:

www.audubon.org/news/how-to-help-birds-beat-the-heat/

www.audubon.org/news/the-many-ways-birds-beat-the-heat/

www.sciencedaily.com/releases/2020/11/201112144038.htm

www.birdlife.org/news/2023/08/02/what-ongoing-heatwaves-could-mean-for -bird-populations/

www.audubon.org/news/when-it-gets-too-hot-phoenixs-lovebirds-turn-air-conditioning/

 

Transcript

Cheryl: Intro:

         Extreme temperatures add stress to an already fragile existence yours, mine and our birds.

Heat extreme is threatening bird populations, with the hottest July on record here in Phoenix behind us let’s look at how birds handle the heat, wildfires, and how we may help.

Kiersten: The adaptions birds have to keep cool.

         Birds in general are well insulated and just like us they heat up when they exercise.  Imagine wearing a down jacket all the time, even when you exercise.  Yep! That’s a bird.  Wild birds are always, in a way, exercising, so birds have to be careful not to overheat.

• Anatomical adaptions: Shorebirds wade in cool water, this helps their bodies to release heat. Waterfowl also use water to regulate their body temperature. 
• Dark Plumage can actually be cooler than white or light-colored feathers. It may seem counterintuitive that so many birds in hot climates are black or darker colored, but studies have found that there are advantages to having these drabber colors.
• 1)Darker feathers do get hotter than white feathers, but because these feathers provide such good insulation very little heat reaches the bird’s skin.
• 2) Dark feathers absorb light and heat at the surface, where it can easily radiate back to the air.  Dark feathers are more resistant to wear and help block UV radiation, dark feathers also allow birds to be more inconspicuous when resting in the shade, but visible to their flock mates.
• Birds don’t sweat, they generally cool off by panting. Gular flutter
• Desert birds have evolved to avoid exertion during the hottest part of the day.
• Many desert bird species have long-term pair bonds and maintain year-round territories, reducing the need for energetic displays. Fighting is relatively rare.  And there are many mechanisms to shelter eggs and chicks from the heat and to provide water.

 

Cheryl: Heat and baby birds

         Extreme heat in the southwest can be devastating to young birds.  Baby birds will jump from nests to find relief from the heat.  Sometimes they find something soft to break their fall, other times not.  A nestling’s tiny body is still in development, and the tiny bird struggles to regulate its temperature-which is one reason why parents sit on their young, to help buffer the cold and the heat. Not only are baby birds less efficient at relieving heat stress, but they also have limited mobility, and this can lead to nestlings in open nests like hawks, some owls, even our curve-billed thrasher babies exposed to direct sunlight.  This sometimes, leads to these birds leaving the nest too early because they are too hot.

         Birds don’t sweat, they pant instead.  Unfortunately, panting is an active process that requires a lot of muscle movement.  So, it is a double-edged sword; to offload heat by panting, birds basically have no choice but to produce heat.  Scientists are concerned that chronic heat stress is going to lead to nest failures.  This could risk the future of 389 North American bird species.

 

Kiersten:  Wildfires

          Wildfires are becoming hotter, more numerous, and fiercer with the warming of the climate, we can see that with the most recent wildfire on Maui.  A wildfire refers to an unintentional, uncontrolled fire. 

How do wildfires impact wildlife and their habitats?  After a wildfire in Flagstaff, two porcupines were seen walking slow and funny, more so than they usually do.  They were picked up by wildlife rescuers.  It was discovered that these animals had burns on their feet from walking on the hot coals.  So, what is happening in the aftermath of fires -just animals having a hard time and being pushed into areas they are not traditionally in. 

Birds, if they can fly, will fly away from the fire, but young birds like nestlings cannot fly, and are left to perish.  Wildlife rehab centers are filled with birds that have had their feathers singed, or melted from the heat of wildfires when flying overhead to get out of the way. 

Scientists are studying the effects of climate change wildfires to better understand how birds and other wildlife manage once their homes have been burned.

 

 

Cheryl: Pros and Cons of the effects of fire on wilderness areas.

Cons:

• Burn and damage vegetation communities, such as rainforests and deserts that take up to hundreds of years to recover.
• Kill or injure individual plants and wildlife, including birds.
• Causes erosion and subsequent sedimentation of creek and wetlands.
• Open up areas to the impacts of weed, invasive plants, and feral animal invasion as well as human access and vandalism.

Pros:

• Heats the soil, cracking seed coats and triggering germination.
• Triggers woody seed pods held in the canopy to open, releasing seed onto a fresh and fertile ash bed.
• Clears thick understory reducing competition for seedlings.
• Encourages new growth that provides food for many animals.
• Creates hollows in logs and trees that can be used by animals for nesting and shelter.

Native animals can escape fire by fleeing to “unburnt islands” within a burn area or to surrounding unburnt vegetation.  Insects, reptiles, and small mammals may be unable to hide underground, and animals that live in trees can move to treetops and escape low to moderate intensity fires.  Birds are the least impacted by fire as they can fly away, but their babies and the eggs can be impacted depending upon the season of the fire or heatwave.  There have been “events” where a large mass of birds has suffered and been lost due to fire.  Several years ago, migratory birds were falling out of the sky over New Mexico due to smoke damage, and starvation.

Kiersten:  Lovebirds and the Phoenix heat.

         Rosy-faced lovebirds are pet trade escapee’s native to southwestern Africa that were first documented in the 1980’s in the Phoenix Valley.  They have flourished in the city where they nest in cavities of ornamental plants and cacti.  Their population is now estimated at more than 2000 individuals.  But the parrots haven’t ventured far outside the city’s urban areas.  This suggests that these birds relay on humans to survive in a desert hotter and drier than their home turf. 

         Phoenix lovebirds have figured out a creative way to beat the heat, by perching on buildings near air-conditioning vents, or swamp cooler vents taking advantage of the cool air that is leaking out through the cracks.  These parrots find their water sources at golf courses, bird baths, fountains and parks with ponds or lakes.  Phoenix’s lovebirds’ inventive adaptions to extreme heat are an example of how birds, and wildlife in general, is going to have to change their behavior to cool in the heat.

Cheryl:  How can we help birds to beat the heat?

• Offer water. The higher the air temperature is the more water they have to evaporate, and the more frequently they have to drink.  Birds cool down by bathing.  The water directly lowers their temperatures and absorbs heat energy as the liquid evaporates from their skin.
• Provide shade. In addition to panting and bathing birds beat the heat simply by avoiding it.  Many species will stop foraging during the hottest part of the day, choosing instead to shelter in cooler, shady spots.
• Supply food. Native plants provide plenty of seeds, berries, and fruit, as well as hosting insects-food resources that can become scarce during periods of extreme heat.
• Heat waves typically happen during breeding season, when 96 percent of native North American bird species depend on butterfly and moth caterpillars to feed their young. You can help those birds feed their babies when temperatures spike by cultivating native plants.
• For some species, bird feeders can also help supplement food resources.
• Take action. Advocating for native plants in parks, and municipal landscapes.  Work with in your community for change to lower temps in your city.

 

Closing:

Humans are impacted by extreme heat just as birds are.  If we make it more comfortable…more survivable for birds on Earth, then humans benefit too.