Red Knots––Nome provides rare access to globetrotting red knots during the breeding season
In 2009 while doing short-eared owl research in the Nome area, U.S. Fish and Wildlife Service biologist Jim Johnson happened upon a red knot nesting area on a ridge along the Teller Road.
At the time little was known about the breeding biology of red knots, a shorebird that nests only in remote and inaccessible areas of the far north. And almost nothing was known about the roselaari subspecies that breeds in northwest Alaska.
Johnson recognized a unique opportunity to study the only known road-accessible breeding population of red knots. The next year he returned with biologists Luke DeCicco and Nick Hajdukovich, also from the Fish and Wildlife Service’s Migratory Bird Program, to begin what is now the longest running study of red knots on the breeding grounds anywhere.
Red knots are long-distance migrants that breed around the circumpolar north and make epic nonstop migrations of up to 9,000 miles to wintering areas far to the south.
There are six subspecies of red knots, all with slightly different physical features, foraging patterns and behaviors on the breeding ground, across vastly different ranges and migratory routes.
This article focuses on information that Johnson and his crew have learned about the subspecies roselaari that breeds here on the Seward Peninsula and in other parts of northwest Alaska, as well as on Wrangel Island in Russia.
In the latter half of May, red knots arrive at scattered nesting areas on sparsely vegetated tundra ridges and domes across the Seward Peninsula and the western Brooks Range. Ridges along the Teller Road are the southern extent of their breeding range.
Male knots typically arrive first, often returning year after year to the same patch of tundra to nest. However, tagging studies show that females tend not to return to previous breeding areas or mates.
Soon after arriving on the breeding ground, males launch into vigorous aerial displays to advertise their territory and attract a mate. The displays can be of remarkable duration and intensity. On one memorable visit to a breeding area in late May, I watched a male display continuously overhead for over an hour, alternating between climbs on quivering wings and shallow glides while broadcasting his far-reaching flight song across the tundra.
Males also make multiple nest scrapes (depressions in the tundra) and advertise them to newly arriving females with a tail-up display. If a female is enticed, she selects her preferred nest scrape and a monogamous pair bond is formed for the season. The female lines the scrape, often with a white lichen with hollow tubes that provides insulation from the cold ground.
Typical of most shorebirds, red knots lay four eggs. The pair shares incubation duty for three weeks. When not incubating, off-duty parents may be seen resting and feeding together in small flocks in the vicinity of their nesting areas.
It is astonishing how well the knot’s mottled rufous, black and gray coloration blends in with the identically colored, lichensplotched, rocky tundra where they often nest. Incubating birds will rely on their cryptic coloration to avoid detection and sometimes sit tight on the nest until they are nearly stepped upon.
Newly hatched chicks are covered in down with beautiful mottled markings for camouflage in the tundra. They are quickly mobile and leave the nest within hours of hatch. The female’s job is done when the eggs hatch, and she soon departs to feed on marine invertebrates on coastal shores, leaving her mate to care for their young alone.
The males are attentive parents, brooding young chicks to keep them warm and dry, and guarding them as they forage for insects on the breeding ground. If danger is present, the male sounds an alarm call and the chicks hunker motionless, virtually impossible to see. The male attempts to lure the threat away with displays of feigned injury or flies directly at a possible predator with loud alarm calls, sometimes giving chase.
The chicks develop a strong bond with each other and communicate with contact calls to stay together. Males watch over their brood even after the chicks begin to fly, defending them until they are about threeweeks-old. Typically, males leave their brood in the first half of July.
By mid-July juveniles usually head to the coast to feed before migration, but this year, due to the late spring, some were late leaving.
Red knots on the breeding ground feed primarily on insects, which provide crucial protein for growth and development of the young. This year chicks grew faster than in the previous ten years of the study.
It is thought that cold conditions this spring delayed the emergence of insects. This resulted in a better match between timing of insect abundance and red knot chick hatch than has occurred in recent years with earlier snowmelt.
Some red knot subspecies are in steep decline and all face varying impacts from climate change.
In 2016, to better understand the effects of climate change on the roselaari subspecies, Johnson began collaborating with Dutch researcher Jan van Gils of the Royal Netherlands Institute for Sea Research and the University of Groningen.
Van Gils has done groundbreaking research on red knot subspecies around the globe. He has documented physical effects of inadequate nutrition from insects on the growth of red knot chicks and the subsequent difficulties they face when attempting to feed on their wintering grounds. His fascinating work on the Seward Peninsula, and elsewhere, will be the subject of a future article.
Johnson has also been involved in research using geolocators and satellite tracking devices to reveal the wintering area, migratory routes and stopovers used by roselaari red knots.
During southward migration virtually all red knots from northwest Alaska and Wrangel Island stop in the Yukon-Kuskokwim Delta to fatten up on clams and other marine invertebrates. For two to four weeks they forage in the rich intertidal zone near river mouths before launching on 3,200-mile, 36-hour nonstop flights to their wintering areas on the Pacific coast of Mexico.
On their northward migration the knots fly shorter legs with more frequent refueling stops which include San Francisco Bay; Grays
Harbor, Washington; the Copper River Delta and the Yukon-Kuskokwim Delta.
Few people are fortunate enough to see red knots during the breeding season. Hike to an alpine ridgeline along the Teller Road in early June, and you may have the rare opportunity to experience this amazing shorebird.
Stay tuned for a future article on red knot research on the Seward Peninsula.