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At least 1,117 records · Page 62Linked to original sources
USGS1986

Activity of radio-tagged black-footed ferrets

Activity of two radio-tagged black-footed ferrets ( Mustela nigripes ) was investigated during October-November 1981 (an adult male monitored for 16 days), and during August-November 1982 (a young female monitored for 101 days). Aboveground activity of the male averaged 2.95 hr/night, 15% of the total time monitored. From 22 September to 5 November, aboveground activity of the female averaged 1.9 hours; 26% of the time she was stationary and 74% of the time she was moving. During August the juvenile female emerged at least once on 93% of the nights. She was least active in November. Both animals were primarily nocturnal (although daylight activity was not uncommon), and timing of nightly activity was similar, peaking from 0100 to 0359.

Great Basin Naturalist Memoirs↗
USGS1986

Fecal bile acids of black-footed ferrets

Fecal bile acid characteristics have been used to identify scats to species of origin. Fecal bile acids in scats from 20 known black-footed ferrets ( Mustela nigripes ), 7 other known small carnivores, and 72 of unknown origin were analyzed to determine if this procedure could be used as a tool to verify ferret presence in an area. Seventeen ferret scats were suitable for analysis and had a mean fecal bile acid index of 156 ± 9. This was significantly different from mean indices for the other carnivores; however, substantial overlap among confidence intervals occurred for badgers, kit foxes, and especially long-tailed weasels. We conclude this method is not useful for making positive identifications if individual ferret scats and suggest that we may be able to definitively identify individual scats with reasonable confidence by using gas-liquid chromatography.

Great Basin Naturalist Memoirs↗
USGS1986

Comparison of capture-recapture and visual count indices of prairie dog densities in black-footed ferret habitat

Black-footed ferrets ( Mustela nigripes ) are dependent on prairie dogs ( Cynomys spp.) for food and on their burrows for shelter and rearing young. A stable prairie dog population may therefore be the most important factor determining the survival of ferrets. A rapid method of determining prairie dog density would be useful for assessing prairie dog density in colonies currently occupied by ferrets and for selecting prairie dog colonies in other areas for ferret translocation. This study showed that visual counts can provide a rapid density estimate. Visual counts of white-tailed prairie dogs ( Cynomys leucurus ) were significantly correlated ( r = 0.95) with mark-recapture population density estimates on two study areas near Meeteetse, Wyoming. Suggestions are given for use of visual counts.

Great Basin Naturalist Memoirs↗
USGS2013

The contributions of Donald Lee Johnson to understanding the Quaternary geologic and biogeographic history of the California Channel Islands

Over a span of 50 years, native Californian Donald Lee Johnson made a number of memorable contributions to our understanding of the California Channel Islands. Among these are (1) recognizing that carbonate dunes, often cemented into eolianite and derived from offshore shelf sediments during lowered sea level, are markers of glacial periods on the Channel Islands; (2) identifying beach rock on the Channel Islands as the northernmost occurrence of this feature on the Pacific Coast of North America; (3) recognizing of the role of human activities in historic landscape modification; (4) identifying both the biogenic and pedogenic origins of caliche “ghost forests” and laminar calcrete forms on the Channel Islands; (5) providing the first soil maps of several of the islands, showing diverse pathways of pedogenesis; (6) pointing out the importance of fire in Quaternary landscape history on the Channel Islands, based on detailed stratigraphic studies; and (7), perhaps his greatest contribution, clarifying the origin of Pleistocene pygmy mammoths on the Channel Islands, due not to imagined ancient land bridges, but rather the superb swimming abilities of proboscideans combined with lowered sea level, favorable paleowinds, and an attractive paleovegetation on the Channel Islands. Don was a classic natural historian in the great tradition of Charles Darwin and George Gaylord Simpson, his role models. Don’s work will remain important and useful for many years and is an inspiration to those researching the California Channel Islands today.

California↗
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↗
USGS1993

Recovery rates of cryptobiotic crusts: inoculant use and assessment methods

Recovery rates of cyanobacterial-lichen soil crusts from disturbance were examined. Plots were either undisturbed or scalped, and scalped plots were either inoculated with surrounding biological crust material or left to recover naturally. Natural recovery rates were found to be very slow. Inoculation significantly hastened recovery for the cyanobacterial/green algal component, lichen cover, lichen species richness, and moss cover. Even with inoculation, however, lichen and moss recovery was minimal. Traditional techniques of assessing recovery visually were found to underestimate time for total recovery. Other techniques, such as extraction of chlorophyll a from surface soil and measurement of sheath material accumulation, were used and are discussed.

Great Basin Naturalist↗
USGS1994

Predation by odonate nymphs on larval razorback suckers (Xyrauchen texanus) under laboratory conditions

High larval mortality has plagued efforts to raise razorback suckers ( Xyrauchen texanus ) in a Lake Mohave, Arizona-Nevada backwater. Observations indicate odonate nymph densities may be high enough to impact larval survival. In laboratory tests conducted in aquaria, damselfly (Coenagrionidae: Enallagma sp.) and dragonfly (Libellulidae: Tramea sp.) nymphs consumed 81% and 76% respectively of 11.8 ± 0.7 mm total length larval razorbacks in 7 days compared to 12% mortality in controls. Larger razorback larvae (14 to 15 mm TL) were less susceptible than smaller fish, showing 53% mortality versus 18% in controls. Extensive growth of sago pondweed ( Potamogeton pectinatus ) may exacerbate predation effects in the backwater, by allowing odonates access to more of the water column.

Southwestern Naturalist↗