Ornithology Journal 6

I went to Laplatte River Marsh Natural Area on April 19th from 12:30-1:30 pm for this field journal. It was a sunny day with blue skies and a couple of clouds. It was around 56 degrees with minimal wind gusts. The habitat was grass and shrubs surrounding the marsh with a few coniferous and deciduous trees surrounding the trail leading to the marsh.

When it came to mate selection I noticed that the Buffleheads were bobbing their heads which could be a form of a display to attract the female Buffleheads. The sexual dimorphism that exits between these birds also shows that the physical display of the male is at play when it comes to attracting a female. The iridescent colors on the Buffleheads which are absent in the females could have evolved due to the females selecting mates based on their appearances.

The Canada geese however stood out to me with their loud vocal behavior. There was a period where there was a pair that was just singing to one another and following one another for 20 minutes. Their use of sound is part of their mating display which shows protection and to get the female's attention. They could have been moving around for so long together to find a good nesting area as well. It was easiest to use the mini activity for the Canada Geese since their sounds are so loud however there were multiple geese around the marsh so the direction and distance from me was constantly changing depending on which geese I was trying to focus on.

When it came to nest selection for the double-crested cormorant and territory selection the cormorants were all flying and diving on the lake and by the marsh area. There was a Double-crested cormorant that didn’t leave the top of a tree the whole time I was observing that area which could indicate that is its nesting area. It would be wise for the Cormorant to have their nests on the trees nearing the water where they dive for various fish so that when they breed it will be near their feeding ground. Around the property, there were many nests surrounding the trees and the marsh that were closer to the top of the trees I would imagine for protection against predators as well as because it was close to materials best suited for nesting such as sticks and grass from the marsh however it is also common for other birds such as the Buffleheads to nest in tree cavities instead. It also is in an area where these water birds can get fish which is a common meal for water birds such as the Bufflehead, Doublecrested cormorant, and the Caspian Tern.

Posted on April 22, 2024 10:02 PM by jloyst