Date of Award

12-2001

Level of Access

Open-Access Thesis

Degree Name

Master of Science (MS)

Department

Wildlife Ecology and Wildlife Conservation

Advisor

Daniel J. Harrison

Second Committee Member

Frederick A. Servello

Third Committee Member

Jerry R. Longcore

Abstract

Nest success is the most important demographic parameter influencing rates of population change of eastern wild turkeys (Meleagris gallopavo si1vestris) and many variables operating at multiple spatial and temporal scales may influence whether a nest is successful. Most studies of nest success and survival of turkeys have occurred in forested or agricultural landscapes; variables influencing nest success have not been studied in suburban landscapes. My objectives were to: 1 ) quantify survival and reproductive parameters of eastern wild turkey hens in the suburban environment of southeastern Connecticut and compare results to studies conducted in other northeastern states; 2) determine which within patch- and within home range-scale variables were most important in determining the success of turkey nests; and 3) quantify nest attentiveness of hens. Fifty-nine hens were equipped with back-pack transmitters during 1996 and 1997. Survival rate of hens during the reproductive period (0.60) and success rate of nests (0.35) were lower in Connecticut than rates reported in most neighboring states. Predation during the reproductive period appeared to be greater on my study sites than on more forested study sites elsewhere in the eastern U.S., possibly due to increased densities of nest predators in suburban environments. I Landscape and cover variables were measured at 38 nests (14 successful, 16 destroyed by predators, 8 abandoned). Multiple linear regression modeling was used to determine relationships between home range-scale fragmentation and cover variables and the number of days each nest survived, and logistic regression modeling was used to compare home range-scale fragmentation and cover characteristics of successful and destroyed nests. The most parsimonious logistic regression model included number of trees and height of ground vegetation as significant descriptor variables. Variables that significantly influenced duration of nest success were number of trees within 10 m of the nest, number of nonwoody stems per 10 m2, and amount of forest within 225 m of nests. These variables probably had indirect influences on wild turkey nest success by influencing detection and encounter rates of predators. Attentiveness data were obtained for 15 nesting hens. Mean values of attentiveness variables did not differ between hens of successful and destroyed nests; however, small sample sizes resulted in high probability of type 11 error. Hens whose nests were destroyed were more likely to leave nests from 1200-1459 hr and successful birds were more Likely to leave nests from 1500-2100 hr. Although it is reported that turkeys have 2 distinct daily periods of intense feeding activity - mid-morning and mid-afternoon, I found that 1200 - 1459 hr was the most frequent time for hens to leave their nests. Predation may be the proximate factor influencing nest success of turkey hens, but the ultimate cause may be habitat related. Despite the ability of hens to decrease the I probability of nest predation by placing nests in forested areas with dense herbaceous or woody understories, fragmentation may have contributed to higher predator densities and subsequent nest predation in this suburban landscape. Thus, long-term studies will be necessary to determine whether incremental increases in forest fragmentation will decrease productivity of turkeys in increasingly suburban environments.

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