Browsing by Subject "Bid monitoring"

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    Conservation Assessment for Bay-breasted Warbler (Dendroica castanea)
    (University of Minnesota Duluth, 2003) Mayasich, Joseph M; Niemi, Gerald J
    This is a draft conservation assessment designed to provide a synopsis of the life history, ecology, and management and conservation concerns of the Bay-breasted Warbler (Dendroica castanea). The primary focus of this conservation assessment is on information relevant to Region 9 of the United States Department of Agriculture Forest Service. The Bay-breasted Warbler is a neotropical migrant that inhabits boreal coniferous forests in a broad band, primarily, across central and eastern Canada. It breeds in northern spruce-fir forests, feeding and nesting in the dense foliage of these conifers. It winters in Panama and northern South America. Males and females are fairly large relative to other members of the genus Dendroica, being 13 to 14 cm long and weighing about 13 g. Bay-breasted Warbler numbers have been reported to dramatically increase and decrease in synchrony with outbreaks and declines of the spruce budworm (Choristoneura fumiferana), a key food item. Its North American breeding distribution is closely correlated with that of spruce and fir in the boreal forest. The greatest threat to the breeding range of the Bay-breasted Warbler is the reduction in the area of old-growth spruce and fir of the boreal forest. Both nesting habitat and food supply (spruce budworm) are at risk when reductions or alterations of these forest areas occurs. Spraying insecticides to control spruce budworm can have direct toxic affect on this Warbler (inhibition of brain acetylcholinesterase activity). Winter habitat degradation and loss is also a threat, as commercial and residential development activity continues to reduce the forested habitats in the tropics. No specific or dedicated management activities have been attempted for the Bay-breasted Warbler in Region 9. If management activities are developed and implemented, they should address ecological sustainability. No past or current conservation activities in Region 9 are known to be relevant to the Bay-breasted Warbler. However, the adoption of an ecosystemcentered forest management perspective within Region 9 would likely help conserve inconspicuous boreal birds such as the Bay-breasted Warbler. No surveying, monitoring or research specific to the Bay-breasted Warbler has occurred or is occurring within the national forests of Region 9, although some generalized bird monitoring is occurring. Modifications to a point-count survey protocol could improve the monitoring of Bay-breasted Warblers in national forests. Considering the limited extent of its habitat within these forests, its migratory behavior and inconspicuous nature, declines in the abundance of Bay-breasted Warblers in Region 9 forests could easily be overlooked.
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    Wildlife species: responses to forest harvesting and management in riparian stands and landscapes
    (University of Minnesota Duluth, 2001) Hanowski, JoAnn M; Danz, Nicholas P; Lind, Jim; Niemi, Gerald J; Wolter, Peter T.
    Breeding birds were surveyed in five watersheds in northern Minnesota for four years. In three watersheds (Knife, Pokegama, Cloquet) 12, 6 to I 0 acre plots were established. In two watersheds (Knife, Gooseberry) one large(> 40 acre) plot was established. Plots were established to assess breeding bird response to harvest type and J:iarvest method in riparian forests. Treatments in the Pokegama watershed included removal of basal area to 25-35 ft within 100 ft of either side of the stream with two different harvest methods (grapple skidding and cut-to-length systems). Uplands adjacent to riparian buffers were clearcut and three total (no harvest) plots were maintained in the watershed as well as three uncut riparian control plots. Before harvest data were collected in 1997, harvest was completed in the fall of 1997, and after harvest data collected in 1998, 1999 and 2000. Treatments in the Knife watershed ranged from clearcut in the riparian area to 25-35 ft residual basal area within 100 feet on one side of the stream. Uplands adjacent to riparian buffers were clearcut and three total (no harvest) plots were maintained in the watershed as well as three uncut riparian control plots. Harvests were not completed on all sites because of poor winter harvest conditions in 1997, 1998 and 1999. Breeding bird data have been collected in all years and will be collected in 200 I if all sites are harvested within this time frame. Treatments on sites in the Cloquet watershed were designed to examine bird response to harvest in the riparian area by leaving residual basal area ( 40 ft2) in either a scattered or clumped pattern. Uplands adjacent to riparian buffers were clearcut and three total (no harvest) plots were maintained in the watershed as well as three uncut riparian control plots. Harvests were not completed on all sites because of poor winter harvest conditions in 1997, 1998 and 1999. Breeding bird data have been collected in all years and will be collected in 2001 if all sites are harvested within this time frame. Bird surveys were also completed on two large sites in Lake County. One site, the Gooseberry was harvested, but the Knife River site was not. No statistical analyses were completed on these data and no additional studies are planned. In addition to breeding bird surveys, two additional tasks were completed and results were presented in the previous biennial report (Louisiana Waterthrush and riparian landscape statistics for the forested regions of Minnesota. No new information is presented in this report on those tasks.