Many marine organisms show significant levels of genetic heterogeneity on local spatial scales despite exhibiting limited genetic structure at large geographic scales which can be produced through a variety of mechanisms. The Arctic cod (Boreogadus saida) is a circumpolar species and is a vital species in Arctic food webs. To examine population genetic structure of Arctic cod at macro- and micro-geographic scales, we characterized variation at mitochondrial DNA (mtDNA) and microsatellite loci among Arctic cod located in the Chukchi and Beaufort seas in Alaska. We found two distinct mtDNA haplotype clusters, although there was no underlying geographic pattern (FST = −0.001). Congruent with this finding, microsatellite loci suggested a panmictic population (FST = 0.001) across northern Alaskan marine waters at a large spatial scale. However, we found slight but significant micro-geographic partitioning of genetic variation in the southern shelf of the Beaufort Sea that appeared to be associated with the western reaches of the Mackenzie River plume. This fine-scale spatial pattern was not associated with kin-associated groups, suggesting larvae cohorts are not remaining together throughout development. We hypothesize that this pattern reflects the intermixing of Pacific and Arctic origin lineages of Arctic cod.

Bird strikes to aircraft are a serious economic and safety problem in the United States, annually causing millions of dollars in damage to civilian and military aircraft and the occasional loss of human life. We observed movements of 1236 neckbanded lesser Canada geese (Bvanta canadensis parvipes) to determine efficacy of hazing as a means to reduce goose presence at Elmendorf Air Force Base (EAFB), Anchorage, Alaska from August to October 1997. Emphasis was on movements of geese onto EAFB with additional data collected at the other two major airports in the area, Anchorage International Airport (AIA) and Merrill Field Airport (MFA). Daily observations indicated the presence of 208 individual neckbanded geese on EAFB, and 20% returned more than once after being hazed from EAFB. We identified three staging areas, geese utilized prior to entering EAFB, and three post-hazing dispersal sites. Collared geese began moving onto EAFB 30-40 days post-molt with the largest proportions moving onto EAFB 70-90 days post-molt. We observed 75 neckbanded geese on AIA from seven molting sites, and 23% returned more than once after being hazed from AIA. We observed 141 neckbanded geese on MFA from 14 molting sites, and 21% returned more than once after being hazed from MFA. Our data indicated that as long as local goose populations increase, large numbers of Anchorage area geese are likely to enter one of the airports creating a variety of management problems. Hazed geese returning to airports multiple times present a special hazard to aircraft safety because they appear to have become habituated to non-lethal scare tactics. We recommend an integrated management approach to limit the Anchorage area goose population utilizing various control techniques which are acceptable to Anchorage residents while continuing the hazing program at area airports.

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We monitored radio-equipped (n = 50) and neck-collared (n = 205) lesser Canada geese (Branfa canadenszs parvzpes) during August through October 1996 i n Anchorage, Alaska, t o ascertain local patterns o f movement and post-molt dispersal; t o identify geese f r o m molting sites that frequent Elmendorf Air Force Base (EAFB); and t o evaluate the effectiveness o f hazing at EAFB. Telemetry data and visual observations o f collared geese indicated 59% o f geese observed at EAFB were from molting sites 5 1 0 k m from EAFB. W e observed 93 marked geese f r o m 11 molting sites 1 or more times i n the EAFB airdrome, and 63% o f geese observed >2 times o n EAFB were f r o m moltlng sites 5 1 0 k m from EAFB. A significant direct relationship was found between proportion o f geese invading the EAFB alrdrome and the distance molting sites were located f r o m EAFB. After attaining flight, geese from the northeast and northwest quadrants o f Anchorage initially moved greater distances from molt sites t o feeding sites than geese from other parts o f Anchorage. Intensive hazing proved effective i n preventing 67% o f marked geese f r o m returning t o the exclusion zone. However, hazed geese dispersed only 3.53 2 0.2 k m f r o m the exclusion zone. Most observations o f marked geese at EAFB occurred during afternoon from 1200 through 1759 hr. Although hazing efforts provided an increased measure of flying safety, w e suggest that managlng geese at the spatial level o f the entire city wlll b e more successful at reducing danger t o aircraft.

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