David T. Cobb

Integrating Early-successional Wildlife and Habitats into North Carolina's 21st Century Landscape

Small game populations, including northern bobwhite, have shown precipitous declines in North Carolina. To address these declines and trends in habitat loss, the North Carolina Wildlife Resources Commission implemented the Cooperative Upland habitat Restoration and Enhancement (CURE) program in August 2000. The CURE program has 6 objectives related directly to habitat enhancement. This is a cooperative, multi-phase project, the success of which depends upon collaboration with numerous private landowners and other agencies and organizations. The CURE program has been designed to minimize...

Research Priorities for Monitoring Wild Turkeys Using Cameras and Infrared Sensors

A persistent shortcoming of wild turkey (Meleagris gallopavo) management programs is the inconsistency in survey techniques. One approach to standardize turkey population monitoring is to use cameras and infrared sensors. The 7 primary assumptions associated with using cameras and infrared sensors to monitor turkey populations can be grouped into those pertaining to baiting and those associated with sampling design. Because none of these assumptions have been tested, our objective is to outline an experimental design appropriate for determining which theoretical assumptions are practically...

Statistical Power in Analyses of Population Trend Data

Non-game Wildlife Outstanding Technical Paper

We developed a Monte Carlo simulation approach to examine statistical power in analysis of population trend data. Our stepwise approach was to perform a regression analysis to test the null hypothesis that the slope of the time series regression line was equal to 0 (i.e., Ho:b = 0 for population count data collected over i years), to use Monte Carlo simulations to calculate the statistical power of the test of H0:b = 0 when Ho was not rejected, and to estimate sample size requirements within and across years to detect a population trend at a specified power, Type I error, and coefficient...

Inter-observer Variability in Wading Bird Survey Data

Evaluating the contribution of wading bird populations to avian biodiversity and wildlife managers' ability to maintain viable wading bird populations requires accurate information on population levels and trends. Wading bird population surveys often use multiple observers in single or over multiple years, but inter-observer variability is seldom evaluated. We conducted a study to test for significant inter-observer variability among experienced biologists and to determine the impact of variability on biologists' ability to accurately survey colonies and to monitor statewide trends in...

Habitat Use and Demography of a Wild Turkey Population Subjected to Human-induced Flooding

From 1986 to 1988, we studied the demography and habitat use of an eastern wild turkey (Meleagris gallopavo silvestris) population subjected to humaninduced flooding along the Roanoke River, North Carolina. A six-month flood from 22 December 1986 to 22 June 1987 resulted in significant shifts in habitat use. Female home ranges during flooding were significantly larger than those recorded during non-flood periods. During non-flood periods, females used bottomland hardwoods more than other available habitats. Habitat use during flooding reflected availability instead of overall resource...

Predicting Wild Turkey Harvest Levels

Reliable pre-season predictions for wild turkey harvests can be an important component of management plans where hunter and/or harvest quotas are used. Data collected in Florida from 1983-1989 included 9 demographic and 4 meteorological variables. Using regression analyses we identified those variables which were associated with spring turkey harvest and produced a "best" regression model for making preseason, spring harvest predictions from data collected during the previous year. Variables identified as most important included: harvest, total number of turkeys observed in late summer...

Population Simulation for Red Fox Management in Kentucky

A stochastic computer model was written to simulate the dynamics of red fox (Vulpes vulpes) populations in Kentucky. The model consists of the main module equations and 2 submodules: ASMOSU and BIRTH. Main module equations calculate the number and density of individuals in each age class and the total population. ASMOSU calculates all total and age specific mortality rates. BIRTH calculates the number of individuals recruited into the 0.5-year age class. The model is useful for evaluating scenarios for red fox management in Kentucky because, except for minor exceptions, it validly...