Turkey Vultures

April 18, 2019 – As springtime advances and the migrants move north, Turkey vultures, those masters of the air currents, are once again gliding across the skies of Northern Illinois in large circling flocks that are sometimes referred to as a kettle. Even though a few of these large dark colored vultures are spotted in northern Illinois during the winter months, most migrate south in the fall after the nesting season. They spend the winter from Southern Illinois and across the southern United States, south through Cuba, Mexico, Central and South America and as far south as ‘the end of the world’ Tierra del Fuego in southern Chile.

North America has three of the six subspecies of Turkey vultures. Cathartes aura septentrionalis is found in the eastern United States.(Palmer, 1988) With a wingspan of around six feet these large slow flying birds are hard to miss as they fly off of the carcass of the unfortunate roadkill as a vehicle approaches. Those close encounters certainly gives the observer an appreciation for the impressive size of the Turkey vulture. They usually don’t go far when flushed from the carrion and soon return to their feeding when the threat is gone. They are often seen still on their roosts in dead trees, utility poles or buildings early in the morning. With their wings spread wide like a parabolic antenna while facing the warm morning sun they are warming their bodies and drying their feathers from a rain shower or the dampness of the night.

Nesting Turkey vultures will use the abandoned nest of other large avian species in secluded areas far from human traffic. They will also use old sheds, barns, and houses that are remote, grown-up, neglected and open to the elements. The Turkey vulture may choose to lay their clutch of 1 to 3 eggs in a nest on the ground that they scrap out in the leaf litter in a dense thicket or near a fallen tree or even in a hollow log. The vultures will have only one brood over a 60-84 day nesting period and may return to the same nest year-after-year according to The Cornell Lab of Ornithology, All About Birds. Palmer, R. 1988. Handbook of North American Birds, Volume 4. New Haven and London: Yale University Press.

Song sparrows

April 11, 2019 – An unrelenting and attention grabbing chase scene was on, as two small Song sparrows pursued each other in an amazing high speed aerial flight that took them zipping between small openings in the woods, over and under bushes, and around trees, a display that lasted well over ten minutes. Soon though, the two birds were on the ground in a small gassy area and appeared to be locked in a serious battle. The pair of male Song sparrows were having a territorial dispute that boiled over into a crescendo of a blurred feathery terror that played out in an opening at the edge of small woods this past week in Iroquois county.

It is not uncommon to see two or more birds having some sort of disagreement over a territory, mate, or reasons not fully understood, but most of the time it only lasts a few seconds with minimal to no physical contact at all. Less often though, one may witness an epic knock-down-drag-out fight at a level that raises a concern of a not so cheerful outcome. The fight which lasted a good four minutes looked at times to be quite violent. The little birds seemed to be going for each others head and face area with those long sharp claws normally used to scratch the earth for seeds and insects.

With the exception of an occasional pause during the fight when the birds had each other restrained, the struggle was much too quick for the human eye to comprehend. The details of the struggle could only be understood in the photos after the fact. Just as quickly as the ground battle started it was all over and they both disappeared from the battlefield. A few minutes later a single male Song sparrow was perched and singing on a small branch nearby as order seemed to have been restored and the intruder had fled the area.

A study that tested the hypothesis of song-matching, “Song Type Matching Is an Honest Early Threat Signal in a Hierarchical Animal Communication System”, was published online in Proceedings of the Royal Society B in 2013. Song matching is the matching of the song of the intruder, sung by the territorial male Song sparrow as an early warning signal to the intruder to stay away. The researchers found that song matching begins at low-level and then switches to higher-level that almost always predicts an attack on the intruder. The bird may also try other signals to send warnings to the intruder such as wing waving combined with song-matching as part of the early warning signals. .Akcay, C., M. E. Tom, S. E. Campbell, and M. D. Beecher. “Song Type Matching Is an Honest Early Threat Signal in a Hierarchical Animal Communication System.” Proceedings of the Royal Society B: Biological Sciences 280, no. 1756 (2013): 20122517. doi:10.1098/rspb.2012.2517.