Timing of ore-related magmatism in the western Alaska Range, southwestern Alaska

Harlan's Hawk (Buteo jamaicensis harlani): A Valid Subspecies

The Auk ◽

10.1093/auk/100.1.161 ◽

1983 ◽

Vol 100 (1) ◽

pp. 161-169

Author(s):

David P. Mindell

Keyword(s):

Glacial Refugium ◽

Tree Line ◽

Alaska Range ◽

Alaska Peninsula ◽

Buteo Jamaicensis ◽

Breeding Range ◽

Southwestern Alaska

Abstract During surveys of 19 different rivers in central and southwestern Alaska, north of the Alaska Peninsula, all Red-tailed Hawks (Buteo jamaicensis) seen were either B. j. harlani or harlani intergrades, demonstrating that harlani does have a breeding range exclusive of other Red-tailed Hawk subspecies and is, therefore, a legitimate subspecies. The range of harlani intergrades was widespread and overlapped the harlani breeding range entirely. The findings presented suggest that the breeding range for harlani and its intergrade forms, exclusive of other Red-tailed Hawk subspecies, is: west to Norton Sound, east to the Alaska Range west slope, north to the tree line, and south to the Alaska Peninsula. Harlani may have diverged morphologically from other Red-tailed Hawks by isolation in a Pleistocene epoch glacial refugium, as has been suggested for other northern bird groups. The possibility of paripatric speciation, however, must also be considered. The characteristics of red in the tail (even small amounts) and white body plumage are discussed as likely intergrade traits.

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Montane-breeding Bird Distribution and Abundance Across National Parks of Southwestern Alaska

Journal of Fish and Wildlife Management ◽

10.3996/062017-jfwm-050 ◽

2018 ◽

Vol 9 (1) ◽

pp. 180-207 ◽

Cited By ~ 1

Author(s):

Courtney L. Amundson ◽

Colleen M. Handel ◽

Daniel R. Ruthrauff ◽

T. Lee Tibbitts ◽

Robert E. Gill

Keyword(s):

Species Richness ◽

Land Cover ◽

National Parks ◽

Detection Probability ◽

National Park ◽

Alaska Range ◽

Alaska Peninsula ◽

Land Cover Types ◽

Survey Effort ◽

Southwestern Alaska

Abstract Between 2004 and 2008, biologists conducted an inventory of breeding birds during May–June primarily in montane areas (>100 m above sea level) of Aniakchak National Monument and Preserve (Aniakchak NMP), Katmai National Park and Preserve (Katmai NPP), and Lake Clark National Park and Preserve (Lake Clark NPP) in southwestern Alaska. Observers conducted 1,021 point counts along 169 transects within 63 10-km × 10-km plots that were randomly selected and stratified by ecological subsection. We created hierarchical N-mixture models to estimate detection probability and abundance for 15 species, including 12 passerines, 2 galliforms, and 1 shorebird. We first modeled detection probability relative to observer, date within season, and proportion of dense vegetation cover around the point, then modeled abundance as a function of land cover composition (proportion of seven coarse-scale land cover types) within 300 m of the survey point. Land cover relationships varied widely among species but most showed selection for low to tall shrubs (0.2–5 m tall) and an avoidance of alpine and dwarf shrub–herbaceous cover types. After adjusting for species not observed, we estimated a minimum of 107 ± 9 species bred in the areas surveyed within the three parks combined. Species richness was negatively associated with elevation and associated land cover types. At comparable levels of survey effort (n = 721 birds detected), species richness was greatest in Lake Clark NPP (75 ± 12 species), lowest in Aniakchak NMP (45 ± 6 species), and intermediate at Katmai NPP (59 ± 10 species). Species richness was similar at equivalent survey effort (n = 973 birds detected) within the Lime Hills, Alaska Range, and Alaska Peninsula ecoregions (68 ± 8; 79 ± 11; 67 ± 11, respectively). Species composition was similar across all three parks and across the three major ecoregions (Alaska Range, Alaska Peninsula, Lime Hills) that encompass them. Our results provide baseline estimates of relative abundance and models of abundance and species richness relative to land cover that can be used to assess future changes in avian distribution. Additionally, these subarctic montane parks may serve as signals of landscape change and barometers for the assessment of population and distributional changes as a result of warming temperatures and changing precipitation patterns.

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