I have recently learned about irruptive birds. The definition of irruptive is– an influx of birds either of a species not normally observed in an area or in greater numbers than normally observed or in a different season than generally observed.
It amuses me when American Robins show up on the Audubon Society rare bird alert in winter months because most of them do in fact leave for the winter. While they are incredibly common in the spring and summer months here they are relatively rare in the winter. I experienced an afternoon last month when our cherry tree was full of robins they must have been migrating though in a flock since I have not seen any since. I am reminded that Robins are the first birds to sing around 4 AM in the spring with their “cherrio cherri up “ songs. It’s very quiet at that time in the winter…
Our most rare back yard bird was a single Tundra Swan who appeared in our wetlands in January. The folks who have lived next door for about 25 years had never seen a swan in the wetlands so this definitely qualifies as an irruptive species, at least for our little area.
The swan was lovely. It was banded and its neckband had a number indicating it was part of an avian flu study originating in Alaska. I was able to find out that this bird, a female, was banded in White Salmon Alaska when she was about 2 years old. Where she has traveled since that time I don’t know. Several of her banding cohorts are currently in the Ridgefield National Wildlife refuge in Washington. Why she became separated from the flock is a mystery. However this bird appeared to find a new flock of Canada and Cackling geese, which is great for socializing and protection from predators.
Other irruptive species are being found more and more in Oregon. This winter we have had unusual ducks including Ring Necked ducks, Common Mergansers as well as many Green Winged Teals and Hooded Mergansers. Who knows why we have so many of these “unusual” birds in our ponds. Of particular note are the sightings of Snowy Owls in the Northwest. I have not seen any in my back yard but am always hopeful…
So birding can be a treasure hunt for rare creatures but now I know the scientific term is “irruptive”. Keeps my brain active but mostly makes me look out the windows… have fun looking..