357. Notes on the vocalizations of Brewer's Sparrow (Spizella breweri)

AbstractBased on distributional, ecologic, morphologic, and vocal data, Klicka et al. (1999) argued in favor of species status for the form taverneri, long regarded as a subspecies of the Brewer's Sparrow (Spizella breweri). For several reasons we disagree with their conclusion: lack of evidence for the reproductive isolation of taverneri from breweri, loss of information on the close relationship and allopatric distribution of the two taxa that would accompany their elevation to species, and violation of the principle of taxonomic balance. Until the demonstration of vocal or display differences relevant to pair formation and maintenance, taverneri and breweri are best regarded as reproductively compatible subspecies.

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Snow Meltout Dates and Breeding Density in Brewer's Sparrows (Spizella Breweri)

The UW National Parks Service Research Station Annual Reports ◽

10.13001/uwnpsrc.2008.3691 ◽

2008 ◽

Vol 31 ◽

pp. 19-21

Author(s):

Martin Cody

Keyword(s):

Census Data ◽

Monitoring Program ◽

Bird Species ◽

Common Species ◽

Breeding Density ◽

Breeding Bird ◽

Data Set ◽

Bird Monitoring ◽

Fixed Area ◽

Spizella Breweri

We have conducted a breeding bird monitoring program in GTNP since the early 1990s, utilizing fixed-area census sites of around 5 ha in size. The sites are located throughout the park in all habitat types and elevations, and number 30 in all. Some have been censused each year in June, at the height of the breeding season, others have been censused repeatedly but more sporadically, and others less frequently. the power of these census data to interpret variation in bird species, composition and breeding densities, species to species, site to site and especially year to year, clearly increases with the longevity of the data set. With the data from some sites now covering 18 successive years (1991-2008), it is possible to attempt some interpretation of the bird species variables. One such is reported here. The influence of snow meltout date on breeding density of a common species of the sagebrush flats, Brewer's Sparrow Spizella breweri.

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Update on the Status and Breeding Phenology of the Timberline Sparrow (Spizella breweri taverneri) in Alaska

Western Birds ◽

10.21199/wb52.3.5 ◽

2021 ◽

Vol 52 (3) ◽

pp. 252-260

Author(s):

Claire M. Stuyck ◽

Paul B. Leonard ◽

Gerald V. Frost ◽

Michelle L. S. Lake ◽

Jeffrey D. Walters

Keyword(s):

Breeding Season ◽

Egg Laying ◽

Alpine Tundra ◽

Breeding Phenology ◽

Active Nest ◽

East Central ◽

The Third ◽

Betula Glandulosa ◽

The Status ◽

Spizella Breweri

In July 2020 we located 10 singing Timberline Sparrows [Spizella (breweri) taverneri] in the region of Gold Hill, Nutzotin Mountains, east-central Alaska. All birds were on southeast-facing slopes in the ecotone between subalpine scrub and alpine tundra, to which habitat breeding Timberline Sparrows seem narrowly confined. The population’s estimated density of 0.77 birds/km2 was similar to that at the time of its discovery in 1994. We located the first active nest of the Timberline Sparrow reported for Alaska, ~0.3 m above the ground in a shrubby resin birch (Betula glandulosa). An observation of young fledged on 11 or 12 July 2020 implies egg laying in the third week of June, later than the beginning of the breeding season of Spizella (breweri) breweri.

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Validation of a novel time-to-event nest density estimator on passerines: An example using Brewer’s sparrows (Spizella breweri)

PLoS ONE ◽

10.1371/journal.pone.0227092 ◽

2019 ◽

Vol 14 (12) ◽

pp. e0227092

Author(s):

Kaitlyn M. Reintsma ◽

Alan H. Harrington ◽

Victoria J. Dreitz

Keyword(s):

Nest Density ◽

Density Estimator ◽

Time To Event ◽

Spizella Breweri

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