Jeffrey Hatfield, Ph.D.
Dr. Jeff Hatfield's duties include field and statistical research on U.S. wildlife and habitats, review of study plans and manuscripts, experimental design, statistical consulting with wildlife biologists, and data analysis. Current research consists of monitoring growth and survival of Hawaiian trees, monitoring regeneration and restoration of vegetation in Texas, monitoring herbivory in National Parks of the National Capital Region, and studies of maternal-effects and Medea genes in snails and mammals.
- Ph.D. 1986. Biostatistics (focus: theoretical ecology & genetics). The Ohio State University, Columbus, Ohio.
- M.A.S. 1982. Applied Statistics (focus: frequentist statistics). The Ohio State University, Columbus, Ohio.
- M.S. 1981. Zoology (focus: aquatic ecology & genetics). Miami University, Oxford, Ohio.
- B.A. 1979. Zoology and Mathematics & Statistics (double major). Miami University, Oxford, Ohio.
Science and Products
The Challenge: The Laysan Teal is an endangered, endemic, Hawaiian dabbling duck that has been pushed to the brink of extinction numerous times. The previous range includes the Main and Northwestern Hawaiian Islands, and its current range is less than 10 sq. km within the National Wildlife Refuges of Papahānaumokuākea Marine National Monument. This non-migratory waterfowl was eliminated from all the Hawaiian Islands except for Laysan by the 1860’s through anthropogenic effects (i.e., introduced rats, shipwrecked mariners, etc.). The Laysan Island population was threatened when guano miners inhabited the island, hunted the duck, and introduced rabbits, devastating the native habitat until they were removed in 1923. Presently, extreme events (e.g., tsunamis, hurricanes, drought, or flooding), disease (e.g., Avian Botulism), sea-level rise, accidental predator or competitor introductions, are ongoing threats to this duck’s survival.
How many Laysan Teal Anas laysanensis are on Midway Atoll? Methods for monitoring abundance after reintroduction
Wildlife managers often request a simple approach to monitor the status of species of concern. In response to that need, we used eight years of monitoring data to estimate population size and test the validity of an index for monitoring accurately the abundance of reintroduced, endangered Laysan Teal Anas laysanensis. The population was...Reynolds, Michelle H.; Courtot, Karen; Hatfield, Jeffrey
Estimating golden-cheeked warbler immigration: Implications for the spatial scale of conservation
Understanding the factors that drive population dynamics is fundamental to species conservation and management. Since the golden-cheeked warbler Setophaga chrysoparia was first listed as endangered, much effort has taken place to monitor warbler abundance, occupancy, reproduction and survival. Yet, despite being directly related to local...Duarte, A.; Weckerly, F.W.; Schaub, M.; Hatfield, Jeffrey S.
Simulating range-wide population and breeding habitat dynamics for an endangered woodland warbler in the face of uncertainty
Population viability analyses provide a quantitative approach that seeks to predict the possible future status of a species of interest under different scenarios and, therefore, can be important components of large-scale species’ conservation programs. We created a model and simulated range-wide population and breeding habitat dynamics for...Adam Duarte; Hatfield, Jeffrey; Todd M. Swannack; Michael R. J. Forstner; M. Clay Green; Floyd W. Weckerly
Long-term monitoring of endangered Laysan ducks: Index validation and population estimates 1998–2012
Monitoring endangered wildlife is essential to assessing management or recovery objectives and learning about population status. We tested assumptions of a population index for endangered Laysan duck (or teal; Anas laysanensis) monitored using mark–resight methods on Laysan Island, Hawai’i. We marked 723 Laysan ducks between 1998 and...Reynolds, Michelle H.; Courtot, Karen; Brinck, Kevin W.; Rehkemper, Cynthia; Hatfield, Jeffrey
Medea genes, handedness and other traits
Medea factors or genes are maternal-effects mechanisms, found in many species, in which the mother's body selectively kills embryos of a certain genotype.Humans have a similar genetic mechanism, the gene RHD which produces Rh-factor involved in blood type.Recently I proposed that RHD acts as a maternal-effects gene that determines handedness (i.e...Hatfield, Jeffrey
Age-specific survival of male golden-cheeked warblers on the Fort Hood Military Reservation, Texas
Population models are essential components of large-scale conservation and management plans for the federally endangered Golden-cheeked Warbler (Setophaga chrysoparia; hereafter GCWA). However, existing models are based on vital rate estimates calculated using relatively small data sets that are now more than a decade old. We estimated more...Duarte, Adam; Hines, James E.; Nichols, James D.; Hatfield, Jeffrey S.; Weckerly, Floyd W.
Spatiotemporal variation in range-wide Golden-cheeked Warbler habitat
Habitat availability ultimately limits the distribution and abundance of wildlife species. Consequently, it is paramount to identify where wildlife habitat is and understand how it changes over time in order to implement large scale wildlife conservation plans. Yet, no work has quantified the degree of change in range-wide breeding habitat for the...Duarte, Adam; Jensen, Jennifer; Hatfield, Jeffrey S.; Weckerly, Floyd
Demographic variation, reintroduction, and persistence of an island duck (Anas laysanensis)
Population variation in life history can be important for predicting successful establishment and persistence of reintroduced populations of endangered species. The Laysan duck (Anas laysanensis) is an endangered bird native to the Hawaiian Archipelago that was extirpated from most islands after the introduction of mammalian predators. Laysan...Reynolds, Michelle H.; Weiser, Emily; Jamieson, Ian; Hatfield, Jeffrey S.
Vascular plant and vertebrate species richness in national parks of the eastern United States
Given the estimates that species diversity is diminishing at 50-100 times the normal rate, it is critical that we be able to evaluate changes in species richness in order to make informed decisions for conserving species diversity. In this study, we examined the potential of vascular plant species richness to be used as a surrogate for vertebrate...Hatfield, Jeffrey S.; Myrick, Kaci E.; Huston, Michael A.; Weckerly, Floyd W.; Green, M. Clay
Dynamics of seabird colonies vulnerable to sea-level rise at French Frigate Shoals, Hawai`i
Globally, seabirds are vulnerable to anthropogenic threats both at sea and on land. Seabirds typically nest colonially and show strong site fidelity; therefore, conservation strategies could benefit from an understanding of the population dynamics and vulnerability of breeding colonies to climate change. More than 350 atolls exist across the...Reynolds, Michelle H.; Courtot, Karen N.; Krause, Crystal M.; Seavy, Nathaniel E.; Hartzell, Paula; Hatfield, Jeff S.
Effects of Canada goose herbivory on the tidal freshwater wetlands in Anacostia Park, 2009-2011
Herbivory has played a major role in dictating vegetation abundance and species composition at Kingman Marsh in Anacostia Park, Washington, D.C., since restoration of this tidal freshwater wetland was initiated in 2000. The diverse and robust vegetative cover that developed in the first year post-reconstruction experienced significant decimation...Krafft, Cairn C.; Hatfield, Jeffrey S.; Hammerschlag, Richard S.
Influence of space use on fitness and the reintroduction success of the Laysan teal
Translocation is an important tool for wildlife conservation and biodiversity restoration, but an inefficient one because of the unpredictability of success. Predictors of success such as habitat quality of the release site and number of individuals released have been identified, but the dynamics of successful translocations remain poorly...Reynolds, M.H.; Hatfield, J.S.; Laniawe, L.P.; Vekasy, M.S.; Klavitter, J.L.; Berkowitz, P.; Crampton, L.H.; Walters, J.R.