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S.A. Wolfe

Publications and source records attributed to S.A. Wolfe.

3 recordsLinked to original sources

Spatial use and habitat associations of Columbian white-tailed deer fawns in southwestern Oregon

Fawns represent a critical life history stage in the dynamics of deer populations, yet little recent information is available on the ecology of neonatal Columbian white-tailed deer (CWTD), a geographically isolated and federally endangered sub-species. We described home ranges, areas of concentrated use, and habitat associations of CWTD fawns in southwestern Oregon during the summers of 1997 and 1998. Spatial use patterns and habitat use within areas of concentrated use were described for 11 radio-marked fawns. Pooled habitat use was described for 24 radio-marked fawns. Areas of concentrated use averaged 2.4 ha, which was 13.3% of mean 95% home range size (18.0 ha). Frequent use of oak-madrone woodland and riparian cover types characterized fawn habitat use patterns. Cover types containing conifers were rarely used and usually not available within home ranges. Although we found no detectable patterns of habitat selection or avoidance among fawns, areas of concentrated use were composed mostly of oak-madrone woodland (35%) and riparian (26%) cover types. Moreover, 74% of concentrated use area was within 200 m of streams. Our results provide useful information on habitat characteristics used frequently by CWTD fawns.

Northwest Science

Chronology and geochemistry of late Holocene eolian deposits in the Brandon Sand Hills, Manitoba, Canada

Accelerator mass spectrometry and conventional radiocarbon age determinations of organic matter from paleosols indicate that the Brandon Sand Hills area of southern Manitoba has been subjected to recurrent intervals of eolian activity in the past 5000 years. Although precise regional correlations are precluded by dating uncertainties, periods of most notable paleosol development occurred around 2300 to 2000, 1400 to 1000, and 600 to 500 cal yr BP with eolian activity occurring before and after each of these periods. Episodes of eolian activity may correspond to periods of regional drought, whereas paleosols mark periods of increased moisture availability and stabilization by vegetation. The geochemistry of the eolian sands, paleosols and source sediments indicates that partial leaching of carbonates occurs from pedogenesis during humid climatic phases, and that this is probably the primary mechanism of carbonate depletion of eolian sands in this area. Recent trends in sand dune activity from historic aerial photography and early explorers' accounts indicate that the few active dunes that presently exist have stabilized at a rate of 10-20% per decade, despite several severe droughts in the 20th century. This may be attributed to pre-settlement droughts that were more severe than those in historic times although regional dune stabilization may also be related, in part, to the spread of forest cover in the past few hundred years. Crown copyright (C) 2000 Published by Elsevier Science Ltd. All rights reserved.

Quaternary International