01 April 2008

Research Essential to Understanding Avifauna at Arctic Refuge

Ongoing research into the habits of notable birds is helping biologists better understand the value of diverse habitats of the Arctic coastal plain.

In Alaska, biologists with the Fish and Wildlife Service are cooperating with a variety of partners to conduct several important projects at the Arctic National Wildlife Refuge, which covers an expanse of 20 million acres. The area is similar in size to South Carolina, with five ecosystem types occurring within this vast land on the shore, and inland from the Beaufort Sea.

Two particular projects of importance during the past couple of years have investigated the biology of the Smith's Longspur and post-breeding activity for a variety of shorebirds, said Steve Kendall, a biologist and refuge ornithologist.

The Arctic NWR is the only federal refuge with significant breeding populations of Smith’s Longspurs, a species of conservation concern, he said. "Little is known about their abundance, distribution and habitat requirements." Two breeding seasons have been spent gathering baseline data, and better understanding their biology.

[Smith's Longspur at Atigun Gorge]

Smith's Longspur's at Atigun Gorge. Photographs courtesy of the Arctic NWR, U.S. Fish and Wildlife Service.

[Smith's Longspur]

These birds have quite an "unusual breeding biology," Kendall said. "They have a polyandrous breeding system, where males mate with several females and vice versa and clutches may have a mixed paternity. The males and females form loose 'neighborhood' groups, with the male longspurs cooperating in rearing the broods."

A graduate student will continue the research this season, trying to "build models to predict abundance and distribution in northern Alaska, while continuing to investigate Smith’s Longspurs’ natural history."

Manomet Center of Conservation Sciences and the University of Alaska, Fairbanks have partnered with the Arctic Refuge to investigate how shorebirds use the coastal areas following the breeding season.

[Breeding season Dunlin at Arctic NWR]

Breeding season Dunlin at Arctic NWR.

[Buff-breasted Sandpiper at Arctic NWR]

Breeding season Buff-breasted Sandpiper.

"Post-breeding shorebird studies thus far have shown considerable inter-annual and within-season variability in use of these habitats," Kendall said. "The mechanisms for this variability are unknown, but may include weather, wind, and water conditions, all of which likely affect food availability."

This habitat is an important place for shorebirds to gather and acquire fat reserves necessary for southward migration, Kendall explained. "Reduced habitat quality at preferred staging areas, through human-caused or natural events, or disturbance causing displacement of staging shorebirds, could impact populations. We have particular concern for the coastal resources of the refuge because these areas are vulnerable to effects of climate change and offshore oil exploration and development of the east Beaufort Sea."

[Capturing post-breeding shorebirds]

Capturing post-breeding shorebirds on mudflats of Beaufort Sea.

[Shorebirds at Jago Delta]

Post-breeding shorebirds at Jago Delta.

The Semipalmated Sandpiper, Red-necked Phalarope, Red Phalarope and Dunlin are more abundant and thus received more focus during this research. The Semipalmated Sandpipers especially have been noted to move from other regions of the coastal plain into the refuge area during the post-breeding period, Kendall said.

Results of additional research on the distribution of breeding shorebirds on the coastal plain of the refuge was published in 2007 in Condor, a prominent journal of ornithology.

[Red-necked Phalarope]

Red-necked Phalarope. Photograph courtesy of Brad Winn.

[Post-breeding Red-necked Phalarope]

Post breeding season Red-necked Phalarope.

Other bird study projects have been done in cooperation with non-governmental groups and corporate partners.

The Wildlife Conservation Society, British Petroleum, Conoco/Phillips and Manomet are partners in the study to evaluate "nest survival" in the vicinity of human infrastructure associated with oil development and villages. Kendall explained that predators can be attracted to land fills and food from people, which may result in differences in predation levels.

Results are currently being evaluated with plans to publish a research paper by the end of the year. The Canning River Delta was the study site on the refuge.

Habitat conditions are an integral part of the research efforts, with changes in sea conditions and land habitat two areas of particular interest.

[Captured Pectoral Sandpiper]

A captured Pectoral Sandpiper.

[Mist netting phalaropes]

Mist-netting post-breeding phalaropes.

Kendall noted that 2007 was an exceptional season on the arctic coast. There was an early ice-out date, with the ice pack far offshore early in the season. Without ice, there was a greater potential for flooding and erosion to change habitats, he said. The local barrier islands were also more prone to the effects of erosion since there was less of the ice cover that would typically limit the erosive impact of waves.

Weather conditions also were a big factor in conditions for local birds last season, Kendall said. Without the ice pack, wind had a greater influence on causing lower water levels. An unusual plankton bloom and an upwelling of aquatic food were readily utilized by foraging birds because of the predominant wind pattern.

Kendall has been the staff ornithologist at the refuge since 2002, when his position was created. He had previously studied birds since 1981 with state or federal positions at the Aleutian Islands, the Yukon River delta and in association with evaluating birds after the Exxon-Valdez oil spill.

He recalls an interesting story regarding the conditions and working with outside partners:

[Boating to Demarcation Bay]

Steve Kendall boating to Demarcation Bay.

"During the 2006 season two partners from Manomet and the Georgia Department of Natural Resources flew up to work with me on surveying all of the major deltas on the Refuge. This required traveling the entire length of the Refuge’s Beaufort Sea coast in a 16 foot inflatable Achilles boat. The east coast of the U.S. was experiencing a heat wave of 100+ degrees when they left. In early August we left Kaktovik for Demarcation Bay, 60 miles to the east on the Alaska/Canada border. It was an exceptional day, with glassy calm seas. Minutes into the trip we started chuckling as a few snow flakes started falling. By the time we reached Demarcation Bay, the chuckles were over as we were traveling in complete white-out conditions in several inches of heavy wet snow. When we arrived at Demarcation, I asked my traveling partners; ‘So how should we begin?’ They looked at me as if I was crazy and said; ‘By heading to shore, building a fire and thinking about camping.’"

Another interesting occurrence happened while working on the Smith’s Longspur project:

"One of the methods we use to survey Smith’s Longspurs is to conduct point counts, where you stand at a randomly selected point and identify species by listening to their calls. At Sunset Pass in 2006, we had several Bluethroats at the study site. This mostly Old World species extends its breeding range into Alaska. They also are accomplished mimics. This ability made surveying a challenge as we could never quite be sure what species we heard singing. Was that a Smith’s Longspur or a Bluethroat mimicking a Smith’s Longspur? At one point we sat and watched a very hyperactive male Bluethroat display. During these aerial displays, we counted him singing the calls of at least 12 species we recognized, plus multiple others we didn’t recognize. At one point he even did a parasitic jaegar call. Jaegers prey on songbirds, by cooperatively hunting them in the air and there were several jaegers in the area. When they heard the bluethroat/jaeger call they came over to investigate. The Bluethroat had to do a quick dive in to the bushes to save himself. We never heard him mimic a jaegar again for the rest of the season."

Kendall's experience with bird studies is an important facet to his knowledge of northland habitats for wild birds, helping his understanding of the role of the Arctic for a variety of birdlife.

"The Arctic Refuge in an incredible place important for a great diversity of species," Kendall said, "and is valuable for many species." The variety of bird research is important in helping to understand and "conserve this wonderful area."

Useful links

Summary of 2007 Activities at Arctic NWR
Smith’s Longspur journal entry
Manomet Bird Observatory

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