Diario de bfchurch

March 21st, 2021
Time: 9:35 am
Weather: Clear, blue skies, S 8 mph wind.
Temperature: 32 F
Habitat: Lake waterfront of Burlington, VT. Along bike path and docks.

Species List:
Common Merganser
Mallard
Common Grackle
Merlin
Common Goldeneye
Northern Cardinal
European Starling
American Robin
Rock Pigeon
Turkey Vulture

On this week's bird outing we walked south along the Burlington bike path. I noticed that the majority of birds we saw were in groups or pairs, rarely on their own. There were a lot more songs and calls as well. I can't say specifically which calls belonged to who, or what they meant because I am not the best at identifying them, but the sheer volume of calls and sound indicated to me that the birds were all trying to call attention to themselves and organize. And of course they are, it's mating season! But how do they all go about it?
We watched a particular group of Goldeneyes out by the breakwater. There were a male, a female, and another female that flew down to the water a little later. As they bobbed in the water the male would rear his head back like a reverse bow. I learned that this is a form of courtship that the male displays to females. In fact, this is one of fourteen different displays according to All About Birds. It is typical to see this behavior in the Spring as the birds try to find mates. Regarding plumages, males are mostly white, with black wings having white windows, a white circle behind their bill, and an iridescent green head. Females are also mostly white, but have brown heads and wings, lacking the white spot behind the bill. The white body may be beneficial when resting on a body of water or flying, as it may blend in better with the sky (looking up from the ground or underneath the water).
This is kind of opposite to the Northern Cardinal, particularly the males, which are bright red pretty much all over. I can't imagine many scenarios in which this helps avoid predators except in large groups. I think that the vibrant color is largely a sexually dimorphic trait that helps attract mates.

Mini Activity: We tried pishing along the trail to get the attention of smaller birds like sparrows and chickadees. Mostly it just scared the birds away, though a group of twenty students would be sure to do that anyhow! It was interesting to note a noticeable decrease in chirps or songs immediately following pishing, as if we had raised the quiet-coyote hand-sign. I think the reason it works to attract attention so well is because the sound is common in the repertoire of a large number of birds that are found all over the world. I think it is used as an alarm or emote signal, so trying to mimic something that means "hey watch out" would certainly get the bird's attention. After doing a little searching, I found that Chickadees are found throughout North America, Europe, and a bit of Mexico. Given that it is a bird common to a large area, other birds and animals may be attuned to their distress or alarm calls. It follows that mimicking this pishing noise would get the attention of other species too!