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Abstract: We compared the effects of two contrasting silvicultural treatments and prescribed fire on bird occupancy at Blacks Mountain Experimental Forest. Each silvicultural treatment was applied to two approximately 100 [...]

We modeled the relationship between egg flotation and age of a developing embryo for 24 species of shorebirds. For 21 species, we used regression analyses to estimate hatching date by modeling egg angle and float height, measured as continuous variables, against embryo age. For eggs early in incubation, we used linear regression analyses to predict hatching date from logit-transformed egg angles only. For late incubation, we used multiple regression analyses to predict hatching date from both egg angles and float heights. In 30 of 36 cases, these equations estimated hatching date to within four days of the true hatching date for each species. After controlling for incubation duration and egg size, flotation patterns did not differ between shorebirds grouped by mass ([greater than or equal to] 100 g or Key words: Charadriidae, embryo age, hatching date, Scolopacidae. Modelamos la relacion entre la flotacion del huevo y la edad de un embrion en desarrollo para 24 especies de aves playeras. Para 21 especies, usamos analisis de regresion para estimar la fecha de eclosion modelando el angulo del huevo y la altura de flotacion, medidos como variables continuas, contra la edad del embrion. Para huevos al inicio del periodo de incubacion, usamos analisis de regresion lineal para predecir la fecha de eclosion solo a partir de la transformacion logit de los angulos de los huevos. Para la parte final del periodo de incubacion, usamos analisis de regresion multiple para predecir la fecha de eclosion a partir de los angulos de los huevos y de la altura de flotacion. En 30 de los 36 casos, estas ecuaciones estimaron la fecha de eclosion con una exactitud de cuatro dias alrededor de la verdadera fecha de eclosion para cada una de las especies consideradas. Luego de ajustar los modelos considerando la duracion de la incubacion y el tamano del huevo, los patrones de flotacion no difirieron entre las aves playeras agrupadas por peso ([greater than or equal to] 100 g 6

Pacific West is poised for a conservation challenge 200 years after Meriwether Lewis and William Clark explored unchartered lands and river discovering 178 plant species and 122 animals. The Wildlife Conservation Society has learned that the key to wildlife conservation is to restore and work with the natural life cycles of streams and forests.

The Argentine workshop organizers had discussed and planned about the real possibility that the Highly Pathogenic Avian Influenza (HPAI) outbreak in the new world. HPAI virus has began spreading from human to human due to handling infected poultry. Details of the HPAI virus infection research are discussed.

We examined the short-term response of the bark-foraging bird community to mechanical thinning, prescribed fire, and thinning/prescribed fire combination treatments designed to reduce fuel loads at study sites throughout the continental United States as part of the national Fire and Fire Surrogate (FFS) project. We modeled the effects of study site, treatment, treatment category, and time since treatment on the foraging encounter rate of four individual species (red-breasted nuthatch [Sitta canadensis], mountain chickadee [Poecile gambeli], hairy woodpecker [Picoides villosus], and brown creeper [Certhia americana]) and assessed the relative importance of several tree and snag characteristics in the selection of foraging trees by these same species. The foraging encounter rate of all four species responded inconsistently across both treatment categories and study sites. Substrate diameter was the strongest and most consistent characteristic positively influencing the selection of foraging habitat structures for all species across all treatment categories. Other influential variables included the presence of bark beetles for red-breasted nuthatches, hairy woodpeckers, and brown creepers in control and burn-only treatment areas and tree species for brown creepers in burn-only and thin-only treatment areas. Although this study did not detect any major negative treatment response by any species, our results suggest that there is substantial variability in the reaction of this particular bird community to fuel reduction treatments and that managers may need to evaluate the effects of these treatments on a site-by-site and species-by-species basis. [ABSTRACT FROM AUTHOR]

Abstract An accumulated body of theory and empirical evidence suggests that habitat selection by animals is a scale-dependent, hierarchical process. Hierarchy theory predicts that habitat suitability is influenced by the interaction of factors at multiple spatial scales from the microsite to the landscape and that higher-order factors impose constraints at lower levels. For instance, large-scale factors such as landscape context may make a site unsuitable for a species even if the vegetation structure and composition are appropriate. In addition, the spatial arrangement of habitat elements at all scales must be considered when planning restoration efforts. For example, the presence of snags does not ensure that the site will be suitable for snag-dependent species. The size, age, and spacing of snags and their juxtaposition to other habitat elements must also be considered. Finally, all habitats are dynamic, and therefore the ecological processes that contribute to those dynamics must be maintained or suitable substitutes included in the recovery plan. When considering restoring habitat for wildlife, we recommend that managers: (1) identify the wildlife species they want to target for restoration efforts, (2) consider the size and landscape context of the restoration site and whether it is appropriate for the target species, (3) identify the habitat elements that are necessary for the target species, (4) develop a strategy for restoring those elements and the ecological processes that maintain them, and (5) implement a long-term monitoring program to gauge the success of the restoration efforts. [ABSTRACT FROM AUTHOR]

The article offers the authors' insights on abundance of species and the collapse of American chestnut Castanea dentate. The authors say that collapses of species abundance have been occurring around the world, citing Astrochelys radiate, which is considered one of the abundant tortoises in the world and is almost extinct. They mention an evidence which showed the variation of individuals within populations which has behavioural and ecological import.

A personal narrative is presented which explores the author's experience of attending the avian flu workshop.

Focuses on the efforts of the author on range conservation on small streams in pine forests in California and Oregon. Status of the Sacramento Valley in California; Riparian habitat in California; Restoration efforts in Oregon.

We compared abundance, daily survival rate, nest site characteristics, food availability, nest activity, and nestling size of Dark-eyed Juncos (Junco hymenulis) between burned and unburned mechanically-thinned ponderosa pine (Pinus ponderosa) forest units, Dark-eyed Junco territory density, number of detections in point counts, and daily nest survival were similar between treatments. Average bare ground was 4.8 times higher and litter cover was 2.6 times lower at nest sites in burned units compared to unburned nest sites. However, there was 28% less burned area around nests compared to random points in burned units, indicating that juncos placed nests in unburned portions of burned units, They also selected non-traditional nesting sites in burned units such as root holes and in trees. Arthropod abundance was higher in burned units 1-year post burn although numbers were similar in the second-year post burn. Nest attentiveness and feeding rates were three times higher in burned units, possibly in response to increased food availability. The potentially negative effect of prescribed burning through reduction of litter and increase in bare ground was offset by novel nesting strategies and increased food availability. [ABSTRACT FROM AUTHOR]