We have previously shown that diets enriched with (n-3) fatty acids reduced the delayed-type hypersensitivity (DTH) skin reaction to keyhole limpet haemocyanin (KLH) in geriatric-Beagles. Although the amount of α-tocopheryl acetate in diets of the previous study exceeded requirements, plasma α-tocopherol concentration was significantly lower in dogs fed the high...
In contrast with other Odocoileus species, Columbian black-tailed deer (Odocoileus hemionus columbianus) population dynamics are not well understood throughout the species’ range. Concerns over apparent long-term population declines have prompted efforts to fill basic knowledge gaps including estimates of vital rates (fecundity, recruitment and survival) and cause-specific mortality. The Oregon...
The ringtail (Bassariscus astutus) is a small, nocturnal, meso-carnivore that occupies mid-elevation forests in the southwest portion of Oregon. Ringtail are fully protected within Oregon, but a species of conservation concern as they may be vulnerable to habitat loss and fragmentation. Limited data exists regarding ringtail ecology in forested ecosystems,...
For over 100 years, National Parks have existed to preserve America’s natural and cultural heritage for current and future generations. As environmental pressures on wildlife and habitats have increased in recent decades, National Park lands have become important protected areas for many threatened and endangered species. Conservation and management of...
Understanding the factors that contribute to or limit reproductive success is a fundamental objective of the field of ecology, providing insight into the ways ecosystems function and facilitating better management of natural resources. Behaviors that benefit offspring often increase costs to parents, and thus parents must adjust their level of...
The assessment of habitat quality for wild populations requires evaluation of vital rates associated with the use of that habitat. Factors associated with bottom-up (forage) or top-down (predation) regulation and the relative contribution of these processes on ungulate populations are difficult to quantify, especially for a cryptic, but widely distributed...
It is critical for wildlife managers to understand the population dynamics of a harvested species, particularly for ungulates, which are a valuable wildlife resource. Due to concerns that mule deer (Odocoileus hemionus) populations in Oregon were declining, more comprehensive data on population vital rates and the factors potentially affecting them...
The Rusty Blackbird (Euphagus carolinus) has suffered significant population declines across its entire geographic range and the mechanisms associated with this decline are poorly understood. Although much of the Rusty Blackbird breeding habitat in Alaska has remained relatively unaltered by anthropogenic activities, this species continues to decline by an estimated...
The red tree vole (Arborimus longicaudus) is an arboreal Arvicoline rodent endemic to conifer dominated forests of western Oregon and northwestern California. While commonly associated with old forests, often inhabiting stands over 80 years old, tree voles have also been found in young forests between 20 and 80 years old....
Preservation of rare plant species often requires establishment of new populations. Survivorship surveys are the most common method of post-introduction monitoring. However, they provide an incomplete picture of establishment success. This study is an attempt to develop a model for determining establishment success by determining the factors affecting recruitment in...