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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Ruffed grouse nutrition and foraging in the southern Appalachians

Hewitt, David Glenn 07 June 2006 (has links)
Feeding trials.showed that ruffed grouse (Bonasa umbellus) performed well on diets containing 20% Christmas hollyfem (Polystichum acrostichoides) or mountain laurel (Kalmia latifolia), but diets containing 40% of these forages resulted in lower protein and energy intake and the Christmas hollyfem diet caused a loss of body mass. Grouse were not able to maintain themselves solely on evergreen leaves. Glucuronide excretion was greatest for the 40% mountain laurel diet. Ornithine conjugate excretion was greatest for a diet with 40% deciduous leaves. Sulfate excretion did not vary among diets. Intake rate of leaves was an asymptotic function of bite size when the density of bites did not limit intake. Intake rate of leaves decreased at plants densities < 322 plants/m2. The maximum intake rate of leaves was 25% of the intake rate of aspen buds observed in wild grouse (Huempfuer and Tester 1988). Intake rate of raisins was an asymptotic function of bite size and was 20 times greater than the intake rate of leaves. Ruffed grouse in the Southeast must forage for> 100 min/day under ideal conditions to satisfy energy requirements. / Ph. D.
22

Relationship of Ruffed Grouse Home Range Size and Movement to Landscape Characteristics in Southwestern Virginia

Fearer, Todd Matthew 11 June 1999 (has links)
I addressed the effects of landscape characteristics on ruffed grouse (Bonasa umbellus) home range size and movement, and examined grouse selection for specific landscape characteristics and cover types. Grouse home ranges and movement patterns derived from telemetry data gathered from fall 1996 through fall 1998 were overlaid onto a GIS database of Clinch Mtn. Wildlife Management Area, VA. This database was developed from GPS data and LANDSAT thematic mapping imagery (30 m pixel scale) and was composed of 22 cover types. Landscape metrics were calculated using FRAGSTATS/ARC, and multiple regression was used to relate changes in home range size and movement to these metrics. I used Wilcoxon signed-rank tests to compare the values of landscape metrics calculated for each home range to those calculated for the area encompassed by the home range plus a surrounding 300 m buffer. I used Wilcoxon rank-sum tests to compare the values of landscape metrics for the home ranges to the metrics calculated for 50 33 ha random plots. I used compositional analysis to test for preferential use of cover types. I developed 2 regression models (P < 0.01) relating changes in home range size to landscape characteristics, 1 model (P = 0.09) relating the distance between seasonal home range centers to landscape characteristics, and 1 model (P = 0.03) relating average daily movement to landscape characteristics. Grouse home range size increased as patch shape became more irregular and patch size and the number of different cover types per hectare increased, and decreased as the amount of high contrast edge in the landscape increased. The distance between seasonal home range centers increased as Shannon's diversity index and the average distance between patches of similar cover types increased, and decreased as the amount of high contrast edge increased. Average daily movement increased as the average distance between patches of the same cover type increased and as the percent cover of a full (~75%) rhododendron and/or laurel understory within a grouse's home range increased, and decreased as the amount of high contrast edge in a bird's home range increased. Ruffed grouse were selecting areas with high densities of smaller than average patches that were of uniform size and regular shape and contained higher than average amounts of high contrast edge. Areas containing a greater diversity of cover types than what was available in the study area also were preferred. Within these areas, clearcuts and mesic deciduous stands with a rhododendron/laurel understory were the most preferred cover types. Creating and maintaining a landscape with high densities of small patches that are of uniform size and regular (square) shape would provide the highest quality ruffed grouse habitat in this region. Several of these patches should be early successional cover to provide an abundance of high contrast edge. Rhododendron and/or laurel thickets also may be beneficial as supplemental winter cover, and mesic stands of mature hardwoods should be well interspersed with these cover types to provide supplemental food sources. / Master of Science
23

Ruffed grouse natality, chick survival, and brood micro-habitat selection in the southern Appalachians

Haulton, G. Scott 30 June 1999 (has links)
Natality characteristics were calculated for 3 regions in the southern Appalachians (Ridge and Valley, Alleghany Plateau, and Ohio River Valley). I report data collected in the first 2 years of a long term (> 6 years) study conducted by the Appalachian Cooperative Grouse Research Project (ACGRP). Nesting rate, pooled over all regions, was 83.6% in 1997 and 79.7% in 1998. In the 2-year period, the Alleghany Plateau reported the highest nesting rate (97.6%) while the Ohio River Valley reported the lowest rate (54.2%). Overall hen success rates were 81.5% in 1997 and 56.9% in 1998. Yearling hen success rates were as high or higher than adults. Adult hen success was 85.7% in 1997 and 48.5% in 1998; yearling hen success was 86.7% in 1997 and 82.3% in 1998. Additionally, I found a lower renest rate (8% over 2 years) in the southern Appalachians than previous studies have reported. The mean first-nest clutch size in the southern Appalachian region was considerably lower (9.5, years and regions pooled) than that reported for other portions of ruffed grouse range. Recommendations are given on how ACGRP natality data collection may be improved in upcoming years. Ruffed grouse chick survival estimates were calculated from data collected in the first 2 years of a long term ACGRP study as well as data collected separate from ACGRP protocol. First-week chick survival estimates ranged from 0.18 to 0.32 in 1997 and 0.45 to 0.48 in 1998. Late brood season survivorship values (0.11-0.13 at week 5, 0.07 at week 10) were considerably lower in the southern Appalachians than those reported from more northern portions of ruffed grouse range. Additionally, the mean number of chicks per brood in July was lower in the southern Appalachians than that reported in the Great Lakes region during July and August. Recommendations are given on how ACGRP chick count data collection may be improved in upcoming years. I compared micro-habitat characteristics at known brood locations with randomly selected locations to determine which characteristics are selected by ruffed grouse hens and broods in the southern Appalachians. In the first half of the brood season (weeks 1-6) hens and broods selected sites with tall, complete, vegetative ground cover. Additionally, broods selected forested sites with a well-developed canopy, rather than areas affected by large canopy gaps or openings. Higher ground cover at brood sites may have been due to a lack of midstory structure. The abundance of arthropods, fruit, and forage at brood flush sites was higher during the first few weeks of the brood season; this was possibly due to flush sites being located in open, mid-age or mature forest. Several authors have speculated that as the chicks' diet shifts from primarily arthropods to fruit and forage at approximately 3 weeks of age, the habitat selected by hens and their broods may change to accommodate this dietary shift. In my study, a change in habitat selection did not occur between weeks 3 and 4 as expected but after week 6 and may indicate the chicks' dietary shift occurs later than some have predicted. / Master of Science
24

Ruffed grouse dispersal: relationships with landscape and consequences for survival

Yoder, James M. 12 October 2004 (has links)
No description available.
25

Population ecology of and the effects of hunting on ruffed grouse (Bonasa umbellus) in the southern and central Appalachians

Devers, Patrick Kevin 18 February 2005 (has links)
I investigated ruffed grouse (Bonasa umbellus) population ecology in the southern and central Appalachians as part of the Appalachian Cooperative Grouse Research Project (ACGRP). Several hypotheses have been offered to explain the low abundance of ruffed grouse in the region including inadequate quantity of early-successional forests due to changes in land use, additive harvest mortality, low productivity and recruitment, and nutritional stress. Through the cooperative nature of the ACGRP, researchers tracked >3,000 ruffed grouse between October 1996 and September 2002 and gathered data on reproduction, recruitment, survival, and mortality factors. As part of the ACGRP My objectives were (1) estimate reproductive rates, (2) estimate survival and cause-specific mortality rates, (3) determine if ruffed grouse harvest in the Appalachian region is compensatory, and (4) estimate ruffed grouse finite population growth. Ruffed grouse population dynamics in the Appalachian region differed greatly from the core of ruffed grouse range. In general, ruffed grouse in the Appalachian region had lower productivity and recruitment, but higher survival than reported for populations in the Great Lakes and southern Canada. However, within the southern and central Appalachian region, ruffed grouse population dynamics differed between oak-hickory and mixed-mesophytic forest associations. Productivity and recruitment were lower in oak-hickory forests, but adult survival was higher than in mixed-mesophytic forests. Furthermore, ruffed grouse productivity and recruitment were more strongly related to hard mast (i.e., acorn) production in oak-hickory forests than in mixed-mesophytic forests. The leading cause of ruffed grouse mortality was avian predation (44% of known mortalities). Harvest mortality accounted for only 12% of all known mortalities and appeared to be compensatory. Population models indicate ruffed grouse populations in the Appalachian region are declining, but estimates vary greatly stressing the need for improved understanding of annual productivity and recruitment. We posit ruffed grouse in the Appalachian region exhibit a clinal population structure and changes in life-history strategies due to gradual changes in the quality of food resources, changes in snow fall and accumulation patterns, and predator communities. Recommendations are presented for habitat and harvest management and future research and management needs. / Ph. D.
26

Ruffed grouse (Bonasa umbellus) habitat ecology in the central and southern Appalachians

Whitaker, Darroch M. 15 January 2004 (has links)
Ruffed grouse populations are low in Appalachian forests, possibly because low habitat quality negatively affects survival, condition, and reproduction. Through the Appalachian Cooperative Grouse Research Project (ACGRP) researchers tracked >1500 radioed grouse at 10 study sites (1996__2002). To improve our understanding of Appalachian grouse habitat ecology, I carried out two primary analyses of this database. First, grouse should be under selective pressure to minimize movements, so I studied factors associated with variation in home range size. Second, importance of a habitat is affected by an individual's resource needs, and I investigated factors associated with variation in selection of "preferred" habitats. Both approaches yielded important insights into the species' regional habitat ecology. As elsewhere, clearcuts, which afford escape cover, formed the cornerstone of grouse habitat in the region. However, a number of other factors were also important. At the root of this was a divergence in habitat ecology between grouse inhabiting the two major forest types in the region. In oak-hickory forests nutritional constraint strongly influenced habitat use. Grouse home ranges increased 2.5x following poor hard mast crops, and at these times grouse increased use of alternate foraging habitats. Grouse, especially females and broods, made extensive use of mesic bottomlands and forest edges, which in oak-hickory forests support relatively abundant soft mast and herbaceous forages. In contrast, grouse inhabiting mixed mesophytic forests were insensitive to hard mast, did not select bottomlands, reduced use of forest edges, and increased use of clearcuts. I feel that greater abundance of birch, cherry, and aspen, buds of which are a high quality winter food, relieves nutritional stress on grouse inhabiting mesophytic forests. A general inference was that grouse attempted to balance competing strategies of maximizing either survival or condition, and the expression of this tradeoff was mediated by forest composition. Also presented here were studies of radiotelemetry error, roost site selection, and suitability of prescribed burning as a habitat improvement technique. In the closing chapter I make recommendations for managing Appalachian forests for grouse, which focus on improving winter foraging habitat, brood habitat, and escape cover, all of which are limiting in Appalachian forests. / Ph. D.

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