The bird migration season is underway, and throughout the month of April and into early May, various bird species will be coming to or through our area for summer breeding.
Understanding migration is a topic of great interest to biologists. The "why" seems obvious – food. There is a substantial benefit to having seasonal food abundance available for the feeding of young. It's the "how" that poses the greater research challenge, which we will review in another column. This week is all about shorebird migration.
Bird species like shorebirds that migrate great distances molt their feathers twice, once into breeding plumage before spring migration and later into winter plumage prior to fall migration. This results in us needing to learn two feather patterns if we want to identify these species. Usually, breeding plumage is more colorful, and most of this week's photographs from Liam show species in their spring colors.
It certainly makes sense from flying efficiency to have fresh feathers, but migrating twice annually places a significant demand on the birds' metabolism. Also, shorebirds typically migrate great distances, which requires tremendous energy reserves and the ability to replace these lost reserves at traditional stopping places along the migratory route.
The smaller shorebirds are migration superstars. These small birds are migrating through our area for the next six weeks or so, sometimes in small flocks but at times in much larger collections. And their assignment – eat, eat, eat!
Birders sometimes call these birds "peeps" because, as a group, they're small and seem to be constantly vocalizing with each other with peep-like sounds. The majority of their populations have been wintering on shorelines in the tropical Americas.
Some species, like the Least Sandpiper and the Western Sandpiper, range in winter as far south as coastal Peru. Others, like the Dunlin, winter in the warmer parts of North and Central America. These are small birds (the Least and Western weigh about 1 oz., the Dunlin weighs a bit more), yet they migrate from these distant areas to their breeding grounds in Arctic coastal areas. For example, the Western Sandpiper gets its common name because it breeds only on the extreme western coast of Alaska.
Other migrating shorebirds are somewhat larger. The Long-billed Dowitcher is robin-sized, about twice as large as the small peeps. It has a very long bill and, in the breeding season, a rusty red wash across its breast and neck. This bird winters widely in the warmer parts of North America, but they all migrate to extreme northern Alaska during breeding season. Another larger shorebird that stops by our area each April is the Red Knot. It is also robin-sized; it has a cinnamon color about its breast and neck and a much shorter bill than the dowitcher.
In the next five to six weeks, you will have an opportunity to see these and many other shorebirds. That's because we live next to one of the most important shorebird migration stopovers in North America – Grays Harbor. With a drive of about 65 miles, you can reach the Grays Harbor National Wildlife Refuge just west of Hoquiam and, with a little planning for tides (and some luck), you can witness huge shorebird flocks, one of the world's great bird migration spectacles.
The economic opportunity of this bird spectacular has not been lost on those supporting Grays Harbor tourism. In recent years, they have developed the Grays Harbor Shorebird Festival. This year's festival is May 5-7, the weekend with the best tides for shorebird viewing.
Shorebirds at Grays Harbor are likely to feed at any hour. Low tides present the birds with a banquet along a vast mudflat, a shorebird feeding bonanza. As the tide rises, the birds concentrate in smaller areas and, at extreme high tides, only a very few areas are exposed for feeding. Thus, the greatest concentrations are to be seen during daylight high tides at the few shore areas that remain uncovered. These areas are at Grays Harbor National Wildlife Refuge and, on the south shore of the harbor, Bottle Beach State Park. The best high tides this year are April 18-20 and May 5-7. Both websites have additional information and many great photographs.
Even if the shorebirds remain at a distance, at times they will fly in very large flocks that wheel left and right, creating amazing flashes of their wing and body colors. Flying in such a dense flock is a defense against the falcon avian predators that follow the migratory flocks on their journey. There are many YouTube videos showing these flights, such as the 18-second example shown at the top of this column.
It's time to plan ahead to visit during this migration; even if you're not a dedicated bird watcher, you will find the sight of these avian athletes inspiring.
George Walter is the environmental program manager at the Nisqually Indian Tribe's natural resources department; he also has a 40+ year interest in bird watching. He may be reached at george@theJOLTnews.com
Photos for this column are provided by Liam Hutcheson, a 15-year-old Olympia area birder and avid photographer.
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