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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.
1

Survival, Habitat Use, And Nest-Site Characteristics Of Wild Turkeys In Central Mississippi

Holder, Brad Douglas 13 May 2006 (has links)
Wild Turkey (Meleagris gallopavo) survival, habitat use, and nest-site characteristics were studied on Malmaison Wildlife Management Area, Mississippi, 2003-2004. Survival rates were 0.55, 0.0004, 0.26, and 0.30 for jakes, adult gobblers, juvenile hens, and adult hens, respectively for the entire study. Spring survival for all groups was 0.51 (95% CI 0.36, 0.65) and was least among seasons. Predation (65%) and harvest (21%) were major causes of mortality. Brood hens used bottomland hardwood stands, pine plantations, and old fields more than expected during the post-nesting period. Non-brood hens used bottomland hardwood stands more than expected during the pre- and post-nesting periods. Forbs were the predominant vegetation type at nests. Vegetation height was 0.3-0.6 m for all nest sites. Vertical screening cover for all nests was in the 21-40% obscurity category at 1 m and 41-60% category at 3 and 5 meters. Vine composition differed between successful (2%) and unsuccessful (20%) nests (P = 0.03).
2

Nest-site Selection and Hatching Success of Three Tern Species Breeding in Baisha Islet, Penghu Island, Taiwan

Lin, Yu-kai 03 September 2007 (has links)
Three tern species, Roseate Tern (Sterna dougalli), Bridled Tern (Sterna anaethetus) and Crested Tern (Sterna bergii) co-bred at Baisha islet, east-north of Penghu, in the summer of 2006. Each species favored different kind of environment for nesting. All Crested Terns nested in the flat plane with vegetation; Roseate Terns in the cliff near the vegetation, and Bridled Tern primarily nested near the vertical rock or under a rocky roof. The Crested Tern had the highest nesting density, and Bridled Tern nested loosely. The hatching success of Roseate (75%) and Crested Tern (73%) were significantly higher than that of Bridled Tern (30%). Roseate and Crested Tern laid eggs synchronously and had apparently two wave of egg laying and the breeding performances between early- and late-laying period were quite different. The relationship between hatching success and nest-site characteristics of the three species was investigated. The results revealed that hatching success of Roseate Tern increased with the number of walls and neighbors. Early-laying nests (79%) and central nests (72%) were more successful than late (11%) and edge nests (45%) of Roseate Terns. The laying-period was also important factors affecting hatching success of Crested Tern. Overall, the low hatching success of the late-laying nests may be due to the change of environmental conditions and the losing advantage of group breeding in the late season. The low hatching success of Bridled Tern was considered owing to the asynchronous laying pattern, loosely built nesting and weak parental behaviors.

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