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R.L. Schroeder

Publications and source records attributed to R.L. Schroeder.

4 recordsLinked to original sources
USGS2004

Managing National Wildlife Refuges for historic or non-historic conditions: Determining the role of the refuge in the ecosystem

The 1997 Refuge Improvement Act mandates that National Wildlife Refuges (NWR) develop Comprehensive Conservation Plans and that the Refuge System be administered in a manner that ensures the biological integrity, diversity, and environmental health of the System are maintained. Refuges must determine their role in the landscape and decide if refuge lands will be managed for historic or non-historic conditions. This decision should be based on an understanding of the Refuge Purpose and supported by available science. Case studies for Sherburne NWR and Bosque del Apache NWR illustrate two possible approaches to determining future management.

Natural Resources Journal↗
USGS1997

Tests of wildlife habitat models to evaluate oak-mast production

We measured oak-mast production and forest structure and composition in the Ozark Mountains of Missouri and tested the accuracy of oak-mast prediction variables from 5 Habitat Suitability Index (HSI) species models. Acorn production was positively associated with several measures of abundance and canopy cover of oak trees, and with an index of mast production for all 5 HSI models. We developed 2 modified oak-mast models, based on inputs related to either oak tree density or oak canopy cover and diversity of oak tree species. The revised models accounted for 22-32% of the variance associated with acorn abundance. Future tests of HSI models should consider: (1) the concept of upper limits imposed by habitat and the effects of nonhabitat factors; (2) the benefits of a top-down approach to model development; and (3) testing models across broad geographic regions.

Wildlife Society Bulletin↗
USGS1992

Summer bird use of Kansas windbreaks

Twenty-four windbreaks in Stafford and Pawnee counties in Kansas were censused for birds during the nesting seasons of 1988-1990. Eighty-nine species of birds were found in the windbreaks with 60 species believed to be nesting. Fifteen species used the windbreaks for feeding or as singing perches but did not nest, and 14 species were spring migrants. Species representing 20 taxonomic families and 15 foraging guilds nested in the windbreaks. Fifteen species were members of the omnivore/ground forager guild. Five species considered forest interior or area sensitive were found nesting in the windbreaks. Windbreak area was important in determining which species were present. Windbreaks provide habitat for a large component of the Great Plains' avifauna, including some species whose populations are decreasing in the region.

Kansas↗