Search

The American Kestrel (Falco sparverius), a small, cavity-nesting falcon that breeds across most of North America, is experiencing an apparent population decline across much of the United States that has yet to be sufficiently explained. With landscape change as a potential factor, the association of landscape composition with kestrel reproduction may assist not only in managing declines but also in improving the effectiveness and efficiency of nest box programs, which can bolster local populations and support monitoring and research efforts. We monitored 163 unique American Kestrel nest boxes over a 12-yr study period (2008–2019) in western Virginia to investigate the factors influencing kestrel reproductive success and we documented relatively high rates of both box occupancy (80%) and nest success (78.9%). In a study area dominated by both high- and low-intensity agriculture, we focused on identifying patterns in land cover composition that may limit reproductive success and associated each box with land cover composition metrics at four spatial scales. Generalized linear mixed models indicated nest boxes with a lower proportion of developed land within 500 m, and a higher proportion of crops and pasture/hay within 3 km were more likely to be occupied by kestrels. Although probability of kestrel nest success increased with reduced proportions of developed land within 100 m, the primary factors influencing success were clutch initiation date and the presence of European starlings (Sturnus vulgaris), with earlier nesting and the absence of starling activity resulting in higher nest success. Overall, cover-type associations with nest success and box occupancy were not strong and establishment of nest boxes in targeted kestrel habitat, while likely maximizing reproductive output, limits research opportunities to identify critical land cover thresholds for the species. [ABSTRACT FROM AUTHOR]

Parents should not object to the supposed racism in Mark Twain's 'Huckleberry Finn' since it can be taught to children as a denouncement of racism written in the 19th century. It also recounts the development of moral integrity in a boy who periodically encounters abuse, discrimination and hypocrisy., Reading these lists of the proscribed is a little like walking into a police station and seeing an unexpected lineup of suspects under glaring lights: The authors, who had seemed [...]

Previously, we thought that we could correctly age female American Kestrels (Falco sparverius) by the width of the dark subterminal band (wide for adults and narrow for juveniles), but others have reported that juvenile female kestrels may have either narrow or wide subterminal bands. Pyle (2008) identifies differences in tail tip shape as a character to distinguish between juvenile and adult female kestrels (wide and blunt on adults, narrow and pointed on juveniles). We show, based on the tails of 169 known-age females, that tail tip shape serves to determine age, but with some caveats. Tail tip shape serves for ageing males based on 79 known-age males. Kestrels that had been aged by molt, recapture, plumage, and fault bars have served to verify the accuracy of tail tip shape in ageing. We found a few cases in which, for various reasons, this technique did not work. We will discuss these herein. [ABSTRACT FROM AUTHOR]

Our research objective was to collect baseline reproductive data on American Kestrels (Falco sparverius) using nest boxes in the Shenandoah Valley Raptor Study Area (SVRSA) in Virginia. From 2008 through 2020, between 4 and 87 nest boxes were available each breeding season. During this 13-year period, 608 nest attempts were made, nest box occupancy by kestrels averaged 82%, and 75% of nest attempts were successful. Clutches were initiated from 7 March through 1 July, peaking around 6 April. Clutch size averaged 4.6 (n=608 nest attempts) and, of 2,791 eggs laid, 72% hatched with 94% of hatchlings surviving to banding age. A total of 1,900 kestrel nestlings were banded in SVRSA boxes, equaling 4.2 per successful box (alternately expressed as 3.1 per nest attempt). Reproductive parameters of kestrels in SVRSA are comparable with two other nest box programs in Virginia and 11 other programs in North America. We present evidence that kestrels in the study area are non-migratory and SVRSA nest boxes sustained high occupancy and success rates for over a decade. [ABSTRACT FROM AUTHOR]

TITAN: THE LIFE OF JOHN D. ROCKEFELLER, SR. BY RON CHERNOW RANDOM HOUSE 774 PAGES $30 Reviewers have discussed the merits of this splendid biography as personal and financial history. [...]

An extremely pale passerine was collected in northern Virginia and identified as a White-throated Sparrow (Zonotrichia albicollis) by the yellow lores and wing edges. Herein we describe the first White-throated Sparrow with dilute plumage termed “pastel”, a genetic condition in which both types of melanin pigments in the feathers are reduced. [ABSTRACT FROM AUTHOR]