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