White winged dove
It’s June in Phoenix – that time of year when you stand in front of the refrigerator with the door open, not because you’re hungry but because you’re wondering if you could fit inside. Riding in the car is a treat because you can set the air at 59 degrees…if you survive the first ten minutes after getting in. Just don’t touch that metal seatbelt buckle! Okay, enough.
What about the wildlife? The outdoor critters take the brunt of the summer inferno. How do they survive?
Doves seem especially immune, as I see them everywhere this time of year. They’re winging arrow-straight routes through the bright skies, humping fleetingly on the searing block walls and raising multiple broods of babies in flimsy twig nests.
Where do they find the gumption? Understanding what these birds are up to answers some of our questions. Summer is breeding season for white winged doves and for mourning doves, so they have important reproductive work to do. The desert provides plenty of nutrition in the way of seeds and cactus fruits during the hottest months, so doves have plenty to feed their young.
Doves are plump birds. (Hunters like them.) Their relatively large body mass offers some protection from heat. Their feathers also provide excellent insulation. Pinau Merlin in her book Bird Nests and Eggs, shares the story of ornithologist Steve Russell who measured the surface temperature on the back of a mourning dove sitting on a nest in midday in June. The thermometer read 160 degrees Fahrenheit. Yet, the bird’s internal temp was only 104.
Doves sitting on babies or eggs in a summertime nest absorb heat from their unfeathered young and dissipate that heat by panting. They also seek shade when possible. Even a thin covering of shade can lower ambient temperatures 15 degrees. I’ve seen doves on the ground with one wing raised like a sail against the sun.
The flimsy looking nests also protect eggs and young from the dangerous heat. The slightest movement of air passes easily through the loosely woven twigs, cooling the eggs and hatchings. Doves turn their eggs throughout the hottest days to keep them from cooking. Using these tools, doves thrive in the desert.
Doves are big drinkers. Unlike some native birds that get their moisture from their food, seed eating doves must drink water. For plump birds with little heads, they are surprisingly strong fliers. You’ve heard the vigorous clapping sound of a dove taking off. Doves easily fly ten miles to reach water.
They rehydrate quickly by sucking water directly into their mouths. Many birds have to raise their heads to let the water trickle down their throats. I see dove flights follow a straight line from the desert to the ponds at the golf course every morning and evening. Doves are also conveniently tolerant of brackish, salty water.
Because many doves may use a water source, a water borne disease called trichomoniasis or canker is a scourge to them. Once the disease takes hold it spreads as mothers feed their young and as raptors such as Cooper’s hawks and red-tailed hawks prey on the doves. If you offer water for birds, make sure to change it frequently, as this disease is very contagious and causes a slow death.
The last cool fact about doves that I’ll share with you? According to the Cornell Lab of Ornithology, the oldest known mourning dove was 31 years and four months old.