and abandonment is causing considerable woodland expansion in many mountainous areas of Europe, with potential repercussions on conservation-sensitive species typical of open habitats. We examined the potential impact of such changes on an alpine golden eagle population, by estimating the ranges potentially used by the eagles for foraging through different techniques (concentric circles of diff...

Bald eagles and red-necked grebes were monitored from 2000 2002 on several lakes along the Pinchi fault, an area with a known source of geologic mercury and previous Hg mining (on Pinchi Lake), in an effort to discern whether increased Hg concentrations were affecting reproductive success and productivity. To determine whether or not Hg levels were elevated, fish tissues (rainbow trout and nort...

Polyhalogenated aromatic hydrocarbons are global contaminants that are often considered to be endocrine disruptors and include 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (p,p'-DDE), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs). The present study examined these compounds and their hydroxylated metabolites or analogues and relationships with circulating thyroid h...

In a recent number of this Journal, Bulmer, Eagles, and Hunter’ have published a study of the direct determination of uric acid in the blood as proposed by the present writer,2 in which the conclusion is reached that figures obtained by the direct method are “unreliable.” We feel that a few words of comment upon that paper may be of service in connection with the still unsettled question of the...

As urban and wild lands come into increasingly closer contact and as demands on wildlife and other natural resources increase, effective and sound ecological management of these resources becomes more critical. This is particularly true in Southeast Alaska where timber harvesting and coastal development continue to threaten Bald Eagle (Haliaeetus leucocephalus) populations. No longer can we sim...

Estimating species density and abundance is challenging but important for establishing conservation management strategies. Significant progress has been made toward estimating Golden Eagle (Aquila chrysaetos) in the conterminous United States of America (USA) much less known about eagle Alaska. Here, we paired migration count GPS-tracking data collected near Gunsight Mountain, Alaska, a Bayesia...

Spatio-temporal patterns of predator aggregations within their settlement areas (i.e. temporary settling zones used during dispersal or, more generally, foraging patches) were studied. By integrating the main behavioural rules of juveniles of Spanish imperial eagles Aquila adalberti during dispersal with the temporal availability of the eagles’ main prey, we have developed several individual-ba...

Habitat alteration is a widespread threat severely affecting large raptors because of their low density and the huge area they inhabit. In this study, we assessed whether human-driven habitat alterations mediated dietary shifts apex predators, focusing on Eastern imperial eagle (Aquila heliaca). Following bottom-up conception (before–after), evaluated effect grassland change eagle’s shift breed...