Most bird biologists go into forests to estimate the number of birds for major population counts. Last winter, associate professor of biology George Farnsworth tested whether birds can count for themselves.
Farnsworth, who earned his Ph.D. at North Carolina State University, spent the winter filming birds landing at his homemade feeder. Farnsworth had studied wood thrush populations in the Smoky Mountains before joining Xavier’s biology faculty in 2003 and spent his first year studying whether birds can distinguish between different amounts of food.
It’s a logical question, considering studies of monkeys, pigeons and even salamanders found that animals know the difference.
In Farnsworth’s tests, a wild mockingbird who visited his wooden feeder in January was offered roasted mealworms in two plastic tubes. Each tube had matchsticks inserted in the sides, preventing the worms from falling out. The bird would remove the matchsticks to get the worms.
Farnsworth varied the tests by changing the number of mealworms in each tube or the number of matchsticks that had to be removed. His theory was the bird would figure out the least effort necessary to obtain the most food. It didn’t work out quite that way. The bird he filmed went randomly from one tube to the next, regardless of the number of worms or matchsticks.
But the third test was the kicker: eight mealworms in one tube versus zero in the other, and one matchstick in each. Ten of 12 times, the bird went first for the tube stuffed with tasty mealworms.
“It means he understands there was no food in the other,” Farnsworth says.
But it still doesn’t prove that birds can count. Farnsworth plans to change his experiment, repeat the study this winter and hope for a flock of results. He, for one, is counting on it.