Treesearch

Using a new computer grading program (UGRS), 1 and 2A Common lumber was sorted based on the percentage of board surface measure found in the maximum allowable number of grading cuttings. For 1 Common, 46.0 percent of 921 boards had percentages in the FAS range (83-1/3% and above). For 2A Common, 54.7 percent of 825 boards had percentages in the 1 Common range. When gang-ripped first, these quality sorts produced important differences in the number of rips, crosscuts, and parts produced for primary and salvage operations when processed to easy and difficult cutting bills. In addition,...

The Asian exotic Amur honeysuckle (Lonicera maackii [Rupr.] Herder) has become the dominant shrub in many forests in southwestern Ohio and in some other locations in the eastern United States. Our research focused on the invasibility of forest communities and relationships of L. maackii to the abundance of tree seedlings and herbs. We surveyed 93 forest stands near Oxford, Ohio (USA) to determine L. maackii cover, time since invasion, tree canopy cover, tree basal area, and a shade tolerance index. Stepwise multiple regression indicated that greater than one-half of the variation (r2 =...

The goal of this workshop was to discuss the development of a strategy to determine the status and assess trends of nocturnal raptor species (i.e., nocturnal owls) in Canada and the USA. A strategy for diurnal raptor species was initiated at a workshop in Boise, Idaho in August 1996. The results of these workshops will form the basis for developing the North American Raptor Monitoring Strategy. This owl workshop focused on nocturnal survey techniques for inventorying and monitoring owls.

A panel of four experts in the fields of environmental education, rehabilitation and research assembled for a 1-3/4 hour workshop chaired by a moderator. Each panelist reflected upon their experiences using live owls in their own environmental education and/or research programs. Permanently disabled or imprinted owls can live long, useful lives as ambassadors from the world of wildlife. Given proper handling, training and care, these owls provide a compelling connection to the natural world for both children and adults. Likewise, an up-close and personal encounter with a wild owl can open...

If low reproductive output plays an important role in the population decline of the Burrowing Owl (Speotyto cunicularia,) in Canada, we predicted the decline would slow or stop in our study population after consecutive years of productivity enhancement via food supplementation and predator exclusion. In the portion of our study site for which historical data existed, the yearly rate of decline averaged 24.7 percent per year before, and 11.8 percent per year after, productivity enhancement. Our overall study population showed no decline after the first year of treatment, but declined 17...

Our multi-scale analysis of Flammulated Owl (Otus flammeolus) habitat use in the northern Rocky Mountains indicates some landscapes may be unsuitable for this species. As a result, there may be less habitat available for Flammulated Owls than thought based on the results of microhabitat studies. Thus, we suggest Flammulated Owl habitat conservation measures be based on the results of landscape-level, as well as microhabitat studies. Habitat conservation and restoration efforts in the ponderosa pine ecosystem should retain large trees, large snags, understory tree thickets, and grassland...

Flammulated Owl (Otus flammeolus) ecology at the northern limit of its range (southern interior of British Columbia) necessitates that inventory data include replicated sampling throughout and between breeding seasons for accurate population and habitat assessment. Auditory census and nest surveys must be linked to assess habitat suitability; census alone can only indicate habitat capability through documentation of presence or absence of Flammulated Owls. Standardization of comprehensive census and nest surveys can provide multi-year population data for landscape management plans. Trend...

The first recorded nesting of a Northern Saw-whet Owl (Aegolius acadicus) in the Snake River Birds of Prey Area in southwestern Idaho occurred in a nest box in 1986. Occupancy of nest boxes by Northern Saw-whet Owls varied considerably (0 to 8 nests per year) over the next 10 years. Numbers of rodents fluctuated during this same period, and the number of nesting Saw-whets was positively correlated with an index of rodent abundance. In contrast, the number of nesting Western Screech-owls (Otus kennicottii) in the boxes was not significantly correlated with the rodent index. Moreover,...

The relationship between landscape (125,664 ha circular plots) fragmentation patterns and the spatial distribution of Burrowing Owls (Speotyto cunicularia) was investigated in the heavily fragmented grasslands of Saskatchewan. Data were collected from 152 Burrowing Owl sites and 250 random sites located on 1990 LANDSAT-TM satellite images and 1:250,000 scale topographic maps. Habitat continuity, patch dimensions and isolation of sites were characterized by 15 variables. The stepwise discriminant function analyses showed that owls were not nesting randomly across the landscape. Habitat...

Building sophisticated habitat models for conservation of owls must stem from an understanding of the relative quality of habitats at a variety of geographic and temporal scales. Developing these models requires knowing the relationship between habitat conditions and owl performance. What measure should be used to compare the quality of habitats? Matrix population models represent a powerful tool to aid in designing habitat research. Through sensitivity and elasticity analysis we can identify the demographic transitions most important in determining population growth. Matrix methods also...