Date: 11/29/18 7:28 pm
From: Mike Patterson <celata...>
Subject: [obol] McKays Bunting - population status
Since I am probably the source to the 5000 figure (a ball-park guess
made without any real basis), I figure I' should probably set this one

From Birds of North America
Montgomerie, R. and B. Lyon (2011). McKay's Bunting (Plectrophenax
hyperboreus), version 2.0. In The Birds of North America (A. F. Poole,
Editor). Cornell Lab of Ornithology, Ithaca, NY, USA.

Population Status

Breeding populations restricted to Hall and St. Matthew islands (Fig. 3)
comprising 326 km2 total land area. Based on counts made from 46
regularly spaced transects (total length 202 km) across both islands
from 30 May to 29 Jun 2003 (Matsuoka and Johnson 2008), total breeding
population size was estimated at 31,200 birds (95%CI = 27,500 – 35,400).
Breeding population density was higher on Hall I. (154 birds/km2) than
on St. Matthew I. (93 birds/km2), probably owing to the greater
preponderance of tundra and rocky upland habitats (Matsuoka and Johnson
2008). Assuming all these birds were breeding, this translates into
breeding densities >5 times the median Snow Bunting densities in Nunavut
(see Snow Bunting account), possibly due to the greater availability of
nest sites or lower predation pressure (Matsuoka and Johnson 2008).

Adult sex ratio observed on transects in the breeding season was 1.33:1
(male:female, n = 2,011 birds) (Matsuoka and Johnson 2008); possibly
male-biased because some females were incubating or brooding and thus
not counted.

Mike Patterson
Astoria, OR
That question...
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