Spring is perhaps my favorite season of the year. I enjoying watching the trees and flowers come into bloom, the birds finding mates and building nests, and the pleasant temperatures. There are the side effects, such as the wind blowing pollen and other allergens into my face, Robins singing outside my window at 4:00am when I’m trying to sleep, and having to wash my car more often due to avian flyovers. One of the things I really enjoy, despite the annoying early birds, is the sound of birds singing in the morning.
From 2012-2014, I spent each spring + summer doing songbird point counts in southern Indiana. My mornings usually consisted of getting up before dawn and recording every bird I heard or saw at my points. Most of the time, you hear birds more than you see them, so knowing the songs and calls of the birds in the area was critical. Nature likes to be tricky, so there were several times where other creatures (chipmunks, frogs, insects) attempted to sound like birds. There were also occasions were the morning chorus of bird songs was almost deafening and picking out individuals was difficult. I usually responded by firing flares into the woods to quiet some of the birds down and make my job easier. Another good response was running around and whacking tree branches with a backpack to reduce the number of birds in the area.
While driving to point count sites early in the morning, I often almost ran over Indigo Buntings sitting in the middle of the road.
Have you ever thought about why birds sing so much in the spring and rarely sing in the winter? The reason for this is not just a response to the nicer weather. The early spring is a great time for birds to migrate to their home range and prepare for the breeding season. Males are the primary singers, though the females of some species (such as Northern Cardinals) may also sing as well. Birds primarily use their voices to claim territories, attract mates, and communicate with other birds. The complexity and length of a male’s song may signal his fitness as a parent to a potential mate. Most birds are believed to learn songs from their father or other members of the species.
The song of the cardinal often sounds like a whistled “birdie birdie birdie” or “sweet-chew sweet-chew sweet-chew”. Other times the song resembles the sounds from a space invaders arcade game.
One of my favorite things to hear in the morning was the song of a Wood Thrush. Many thrushes are capable of singing two different notes separately or at the same time, making it sound like two birds are singing. Wood Thrushes were the main study bird, which was good. If the focus bird had been something like a hoarse crow, listening to the calls would not have been as pleasant. Anyway, one of the experiments I was a part of involved using playback of thrush recordings and measuring the responses by Wood Thrushes. Apparently male thrushes don’t usually like intruders that encroach upon their territory. We were also testing to see if the playback affected nesting choices in the following years. Basically, my boss wanted to know if the presence of wood thrush draw in young males scouting for the following year (believing that the territory is good for raising young), or if the songs repel males and push them toward other territories.
If you’ve never gone for a walk out in nature on an early spring morning, I encourage you to do so. Listen to the symphony of bird songs and watch as the birds, forage for food, find mates, and build nests. Nature’s orchestra can be quite peaceful and beautiful, as long as the crows and jays aren’t yapping their heads off. Now if you’ll excuse me, I’m going to go head-bob while listening to bird calls.