Autumn is upon us. It officially occurred last Thursday. Climatologically September 1st marks the beginning of Autumn. For us Dawn Chorus denizens the fall migration marks our start of Autumn.
The beginning of calendar Autumn marks the peak of migration, give or take a couple of weeks, depending on your location. As the more northern breeders pass through the species that breed in our locales start joining them on their way to more hospitable winter digs. This migration can be multidirectional depending on your location. Not only may it be just a north-south move. Migration can also be vertical in more mountainous areas and lateral in areas closer to the coasts as the birds move into more moderate winter climes.
Many of us do not just see the coming winter as a cold, rainy/icy/snowy season with reduced sunlight in strength and length. We also see it by the change of the more dominate species groups we can observe. For me this is Sparrow/Waterfowl/Raptor/Gull and vagrant season. I will be referring to valley locations in my area for these birds.
I’ll start with the vagrant part. I am close enough to the ocean at about 140 miles for winter storms to blow in species that are considered to be more marine species. We get Surf, White-winged and Black Scoters, Red-necked Grebes, Red-breasted Mergansers, Red-throated and Pacific Loons and some Greater Scaups. The Surf Scoters and Greater Scaups seem to be the most consistently found species with the others being seen every couple to few years. Storms that come in from the north and northeast can bring us species that tend to stay closer to the Rockies and to the north of us, most notably Trumpeter Swans. Storms that swing up from the south and southeast can transport some of the birds that overwinter in southern California and western Arizona.
The sparrows are White-crowned and Golden-crowned Sparrows mainly. We get some White-throated Sparrows mixed in every year. Dark-eyed Juncos migrate in and some come down from the mountains.
Gulls see the California and Ring-billed Gulls joined by Herring Gulls. We get a few Glaucous-winged and Iceland (Thayer’s) Gulls that seem to overwinter. Vagrants tend to be Short-billed Gulls, whose name may well change back to Mew Gull in the upcoming taxonomy/ common name update, and Glaucous Gulls.
Raptors see the return to a larger number of Red-tailed Hawks, with sightings of Golden and Bald Eagles increased. Peregrine Falcons are seen more and Merlins return to the area. Ferruginous and Rough-legged Hawks also return. A few Short-eared Owls make appearances.
Waterfowl seem to make the greatest changes. Not only are the ducks more visible back in their breeding colors, they are concentrated more by ice on ponds and lakes. Their flocks come back together, too. Buffleheads, Goldeneyes, Scaups, Ring-necked Ducks, Hooded Mergansers, a few Horned Grebes and Common Loons, various sub-species of Canada and Cackling Geese, plus Greater White-fronted Geese show up, Snow and a few Ross’s Geese make the rounds as well as Tundra Swans.
My favorites are all of the Raptors, Buffleheads, Hooded Mergansers and the Swans. The gaudy colors of the Drakes are always a welcome sight. The vagrants tend to truly make the season for me though. I think the chase and finding of a rare/unusual bird give a perfect adrenaline rush to warm the season.
What species do you look forward to in the post fall migration period?
Dawn Chorus is now open for your birdy observations of the week.