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Factors affecting within-season and between-season breeding dispersal of burrowing owls in California /Catlin, Daniel H. January 2004 (has links)
Thesis (M.S.)--Oregon State University, 2004. / Includes bibliographical references (p. 94-97). Also available via the World Wide Web.
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Behavioral and morphological adaptations to burrowing of two species of Dactyloscopid fishes from the northern Gulf of CaliforniaPetti, John Carmine, 1942- January 1969 (has links)
No description available.
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Mechanics of burrowing in muddy sediments /Dorgan, Kelly M., January 2007 (has links)
Thesis (Ph.D.) in Oceanography--University of Maine, 2007. / Includes vita. Includes bibliographical references (leaves 185-195).
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Nest habitat selection of burrowing owls in relation to soils, burrow availability, and burrow temperatureLarson, Kyle Blake, January 2009 (has links) (PDF)
Thesis (M.S. in environmental science)--Washington State University, August 2009. / Title from PDF title page (viewed on Sept. 17, 2009). "School of Earth and Environmental Sciences." Includes bibliographical references (p. 35-42).
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The role of aardvarks (Orycteropus afer) as ecosystem engineers in arid and semi-arid landscapes of South Africa /Whittington-Jones, Gareth Morgan. January 2006 (has links)
Thesis (M.Sc. (Zoology & Entomology)) - Rhodes University, 2007.
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Influence of local and landscape characteristics of Prairie Dog colonies on Burrowing Owl nest ecology in South DakotaBly, Kristy Lee Sydney. January 2008 (has links) (PDF)
Thesis (M.S.)--Montana State University--Bozeman, 2008. / Typescript. Chairperson, Graduate Committee: Mark Taper. Includes bibliographical references.
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Effects of burrowing by mountain beaver (Aplodontia rufa) on soil in a young forest in the Oregon Coast Range /Russell, William Ogburn, January 1997 (has links)
Thesis (M.S.)--Oregon State University, 1998. / Typescript (photocopy). Includes bibliographical references (leaves 44-50). Also available on the World Wide Web.
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Mechanics of Burrowing in Muddy SedimentsDorgan, Kelly M. January 2007 (has links) (PDF)
No description available.
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Habitat selection, reproductive success, and site fidelity of burrowing owls in a grassland ecosystemRonan, Noelle A. 21 February 2002 (has links)
I used a comparative and experimental approach to examine nest habitat
selection, reproductive success, and nest site fidelity of burrowing owls (Athene
cunicularia) in a large, non-fragmented grassland in southwest California. In 1999,
I compared habitat characteristics between nest sites (n = 31) and randomly
selected, unoccupied burrows (n = 31) in the local vicinity of the nest (paired
burrows). In 2000, I compared habitat characteristics between nest sites (n = 33)
and randomly selected, unoccupied burrows (n 32) within the study area
(unpaired burrows). I examined reproductive success and variation in nest habitat
characteristics, diet quality, and intraspecific competition using data from 1998,
1999, and 2000. I experimentally (n = 11 control and 11 treatment nests) assessed
the effect of satellite burrow (multiple auxiliary burrows near the nest) use on
productivity and behavior.
I found little variation in habitat between nest sites and unoccupied burrows.
Habitat selection was not strong when nests and unoccupied burrows were spatially
correlated (paired burrows). However, nest sites had a larger number of large
diameter burrows, satellite burrows, and perches than the unpaired burrows.
Nest success ( I young fledged) and productivity (the number of young
alive at 14 -21 days) varied substantially among some years, though the habitat
variables I tested did not explain reproductive success when both failed and
successful nests were evaluated. When nests were successful, productivity was
influenced by rodent consumption. Nest fidelity within the breeding season was
highly correlated with nest success. Nest abandonment occurred at 83% (n = 15 of
18), 92% (n = 12 of 13), and 83% (n = 20 of 24) of the failed nests in 1998, 1999,
and 2000, respectively.
Results of the experimental manipulation of satellite burrow access showed
that productivity did not differ between groups but demonstrated that burrowing
owls will adjust their behavior to use satellites. Owls in the treatment group (71%;
n = 5 of 7) responded by moving their families to areas with access to satellite
burrows but none of the control group owl families moved.
This study illustrates the importance of identifying critical factors affecting
reproductive success of burrowing owls in large grasslands. Maintenance of
burrowing mammal populations to provide nest and satellite burrows will be
important for protecting burrowing owls. Also, temporal dynamics influenced
reproductive success. Habitat characteristics that enhance foraging ability may
benefit productivity, especially in years of low rodent numbers. Furthermore,
temporal variation in nest success may lead to low nest site fidelity. / Graduation date: 2002
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Evaluating space use and pesticide exposure risk for burrowing owls in an agricultural environmentGervais, Jennifer A. 22 April 2002 (has links)
Large burrowing owl (Aihene cunicularia) populations exist in areas of
intensive agriculture in California, and pesticide exposure has been identified as a
potential threat to population persistence. I evaluated breeding season use of
agricultural fields by adult male owls using radio telemetry, and examined egg
contaminant residues to estimate population-level effects on reproduction and
survival. Reproduction and survival were estimated annually, and an index of diet
was inferred from pellet samples. A total of 11 adult males in 1998 and 22 in 1999
were successfully radio-tracked. Mean fixed kernel home range sizes were 172 ha
(SE=68) in 1998 and 98 ha (SE=16) in 1999. Pellet analyses indicated a
substantial increase in the numbers of rodents consumed in 1999, associated with an
observed population explosion of California voles (Microtus calfornicus). Distance
to the nest was the most important factor in differentiating between foraging and
random locations, and there was no tendency to select or avoid any cover type.
Owls did forage in agricultural fields, but I failed to find evidence of selection or
avoidance of fields recently treated with pesticides. A total of 92 eggs were
collected over 5 years. Egg contaminants were generally limited to the presence of
p,p'DDE, which fluctuated by 4 orders of magnitude among years, from 0.05 ug/g
to 33 ug/g fresh weight p,p'DDE. There was a general pattern of decline in egg
residues over time for individual birds. The levels of p,p'DDE I documented did not
appear to have any effect on either productivity or survival of adult females, nor
were they clearly related to diet. I modeled the effects of various pesticide exposure
impacts on demographic rates and determined that exposure rates based on field
data would lead to relatively minor declines in population growth rate. An elasticity
analysis of burrowing owl demographic parameters revealed a variable pattern, but
generally indicated that factors influencing anyone of the demographic parameters
of burrowing owls can have a substantial impact on population growth rate. / Graduation date: 2002
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