Wild Georgia: Fall is fattening-up time in nature

It’s hyperphagia season. Bears, birds and deer do it. Even ladybugs do it. Hyperphagia is the term for food-gorging among wild creatures at this time of year to quickly fatten up and prepare for winter survival.

For migratory birds, extra layers of fat also provide vital energy to fly long distances to Latin America and the Caribbean for the winter. Since late July, for instance, ruby-throated hummingbirds have been streaming to feeders and flower blooms to lap up nectar in what is called “pre-migration hyperphagia.”

During this period, ruby-throats may consume their entire body weight of 3 grams in nectar every day. The resulting fat supplies the fuel to propel them on their arduous journey to winter grounds in Mexico and Central America. Part of that trek takes them some 500 miles nonstop over the Gulf of Mexico to landfall in the Yucatan Peninsula. Most ruby-throats will be gone from Georgia by mid-October.

For white-tailed deer, both bucks and does push to add on weight during fall by gobbling up high-fat foods like acorns and other wild “mast,” which also includes hickory and beech nuts and fruits and berries. Bucks especially need extra fat because they can lose 25% of their body weight from chasing does during the mating season, which begins in October. A poor mast crop in fall and winter also can result in does producing fewer fawns in spring.

ExploreBear spotted roaming north metro Atlanta neighborhoods

In particular, black bears, whose mating season ended in late August, are in a power-eating frenzy now to prepare for winter slumber in dens (though not true hibernation in Georgia). During hyperphagia, bears may need to consume 10 times the calories that they need in spring and summer.

So intense is their appetite now that they may wander far and wide to find the extra rations they need. They’re also apt to take more risks, such as venturing near homes and campgrounds or crossing busy highways.

No surprise, then, that reports often pop up at this time of year of black bears roaming neighborhoods and backyards, leaving in their wake destroyed bird feeders and rummaged-through garbage cans.

IN THE SKY: From David Dundee, Tellus Science Museum astronomer: The moon will be new on Sunday. Rising in the east are Venus, shortly before sunrise; Mars, just before midnight; Jupiter, at sunset; and Saturn, just after dark. Mercury is not visible now.

Charles Seabrook can be reached at charles.seabrook@yahoo.com.