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Survey Design and Behavioral Ecology of Lapland Longspurs in Northern Alaska
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 Lapland longspurs are a common breeding passerine on the tundra of northern Alaska and throughout the holarctic. This study has two components: the design of an area census survey method for Lapland longspurs with applicability to other highly visible species in open habitats, and 2) the description and quantification of the Lapland longspur mating system.
Survey design. Survey principles and techniques that facilitate the rapid and efficient monitoring of tundra-breeding species over large areas will be useful to organizations, such as U.S. Fish and Wildlife Service, that are interested in bird abundance, spatial distribution, and population trends. Monitoring abundance of small tundra birds is a difficult and poorly studied topic. Visibility, typical species behaviors, and the compressed nature of the breeding season make monitoring small birds on the tundra different than monitoring in other habitats and in temperate regions. This study 1) incorporates data on the spatial stability of Lapland longspur pairs and the phenology of male behaviors into survey design, and 2) develops an area census method for estimating longspur density and determine its accuracy and applicability to other species.
Mating strategies. Male Lapland longspurs have been described as being primarily socially monogamous but attempting extra-pair copulations (EPCs) after their mate=s clutch is complete. Previous studies have not quantified male display rate, mate-guarding, or other mating behavior nor attempted to address their evolutionary costs and benefits. Lapland longspurs at our study site provide a rare opportunity to study these mating strategies in a habitat in which both males and females are nearly always visible. This study describes and quantifies the extent to which male longspurs combine strategies of mate-guarding, territoriality, and seeking EPCs in a manner that protects within-pair paternity and furthers extra-pair paternity.
In each of the 5 years during 1995-1998, time-budgets were conducted on the 10-15 pairs that establish territories on the permanent plots. Males and females were captured and banded soon after arrival and during early incubation. Blood samples were taken from all captured adults and from 9 complete families (small sample due to most nests being predated during incubation). The efficiency of the area census method was evaluated by comparing results from 6 observers on 4 plots to the actual number of territorial males present in 1997 and 1998.
Preliminary Results
Behavioral data clearly indicate that males follow a mixed reproductive strategy in which a male guards his mate from extra-pair copulations during the female's fertile period and seeks extra-pair copulations with neighboring females when his mate is not fertile (i.e., during incubation). Results suggest that the area census method is reasonably accurate for small study sites with relatively few territorial males (approximately 12) but more accurate for large sites (>50 males) or when sites are pooled. Survey principles applicable to Lapland longspurs are likely relevant to tundra-breeding shorebirds, and perhaps grassland-breeding songbirds (e.g., meadowlarks, bobolinks), that are highly visible during aerial displays or at song perches.
Dr. Jonathan Bart, also of the Snake River Field Station, collaborates on the survey design component of this study. This project is funded, in part, by the U.S. Fish and Wildlife Service, Region 7, Office of Migratory Birds, Nongame Bird Program, Anchorage, Alaska
Susan Earnst
Address: USGS Snake River Field Station
Address: 970 Lusk Street
Address: Boise, ID 83706
Phone: 208-426-5209
E-mail: susan_earnst@usgs.gov
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