The Backyard Birder in today's OC Register

My column ran in today's paper. It's not yet posted on Register's Website, so here it is:

How birds beat the heat

             When temperatures skyrocket, even the birds have to find ways to keep their cool. 

             Birds possess both physiological and behavioral adaptations to help them beat the heat.  Scientists refer to this as thermoregulation.

 “Birds maintain a constant body temperature of 105 to 107 degrees,” said Trude Hurd, Education Project Director for Sea and Sage Audubon.  “So birds can easily overheat.”

Without sweat glands, they can’t perspire like humans, nor do they pant like dogs.  Instead, birds open their bills to expose their mucous membranes to the air, which sends cooler air into their air sacs, Hurd said.  They also flutter their throats in a form of avian panting called “gular fluttering.”

Birds sleek down their feathers to avoid trapping air next to their skin when the environment is too warm.   And like many other species, birds will become less active in the heat.  They will retreat to the shade where they can hide and cool off.  

It’s also common to see birds sitting with open wings, which circulates air next to their bodies.  Some species are known to spread their wings to shade their nestlings from the sun.  Female hummingbirds will beat their wings over their nests to cool their eggs or hatchlings.

Other species have more unusual behaviors such as vultures that cool off by excreting over their legs, Hurd said.

And of course, birds can cool off in water.  We can help our backyard birds by providing a clean water source for drinking and bathing, she said.  

Having a fountain or birdbath helps attract species that do not visit backyard birdfeeders.  All birds are attracted to moving water.  In the absence of a pump, small battery powered gadgets such as the Water Wiggler available at garden and nature stores help keep the water moving in a birdbath.  Stagnant water can play host to mosquito larvae, which is factor in the spread of West Nile Virus.  It’s also important to clean the birdbath every few days, especially in the heat.

Consider adding a mister or dripper to your birdbath for hummingbirds and other species that love to shower.  Watching birds fly through a mister is like watching children at a waterpark.  Large open rose blooms that collect overspray from misters and sprinklers act as nature’s bathtubs for hummers.

            This year, hummingbirds need special assistance in areas affected by drought and wildfires.  With fewer wildflowers, hummers are turning to nectar feeders.  Prepare nectar in a 4:1 ratio of water and sugar.  Use pure granulated sugar and skip the red dye, which is unnecessary and potentially harmful to the birds.  Boil your solution for three minutes to dissolve.  Boiling also helps retard spoiling of the nectar.

            “In this heat, it’s best to change it daily,” Hurd said.  A sugar solution can ferment in the sun in as little as one day.  Prepared nectar can be stored for two weeks in a glass container in the refrigerator.  

Happy Birding!

J.J.