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.
Recent Accomplishments
Education
- 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.
Professional Studies/Experience
Mentorship/Outreach
Professional societies/affiliations/committees/editorial boards
Honors, awards, recognition, elected offices
Scientific/Oral Presentations, Abstracts
Science and Products
Filter Total Items: 54
Temporal variation in bird counts within a Hawaiian rainforest Temporal variation in bird counts within a Hawaiian rainforest
We studied monthly and annual variation in density estimates of nine forest bird species along an elevational gradient in an east Maui rainforest. We conducted monthly variable circular-plot counts for 36 consecutive months along transects running downhill from timberline. Density estimates were compared by month, year, and station for all resident bird species with sizeable populations
Authors
John C. Simon, T.K. Pratt, Kim E. Berlin, James R. Kowalsky, S.G. Fancy, Jeff S. Hatfield
Behavioral effects of environmental enrichment on harbor seals (Phoca vitulina concolor) and gray seals (Halichoerus grypus) Behavioral effects of environmental enrichment on harbor seals (Phoca vitulina concolor) and gray seals (Halichoerus grypus)
Zoos and aquariums have been incorporating environmental enrichment into their animal care programs for the past 30 years to increase mental stimulation and promote natural behaviors. However, most attempts to document the effects of enrichment on animal behavior have focused on terrestrial mammals. Staff at the National Aquarium in Baltimore conducted an investigation of the behavioral...
Authors
S. A. Hunter, M. S. Bay, M. L. Martin, Jeffrey S. Hatfield
`Akohekohe response to flower availability: seasonal abundance, foraging, breeding, and molt `Akohekohe response to flower availability: seasonal abundance, foraging, breeding, and molt
We studied the relationship of flower availability to the seasonality of life history events of the `Akohekohe (Palmeria dolei), a primarily nectarivorous and endangered Hawaiian honeycreeper from montane rain forests on Maui, Hawai`i. For comparison, we also investigated temporal bird density and foraging behavior of three other competing Hawaiian honeycreepers: `Apapane (Himatione...
Authors
Kim E. Berlin, John C. Simon, T.K. Pratt, James R. Kowalsky, Jeff S. Hatfield
Water conditioning and whooping crane survival after release in Florida Water conditioning and whooping crane survival after release in Florida
About 50% of the whooping cranes (Grus americana) released in Florida die within the first year of release. Most of these deaths and those in subsequent years result from bobcat (Lynx rufus) predation. Choosing release sites in open marshes away from bobcat habitat has improved survival. We hypothesized that exposure to ponds (water conditioning) at the rearing site would encourage birds...
Authors
G.F. Gee, Jane M. Nicolich, S.A. Nesbitt, Jeff S. Hatfield, D. H. Ellis, Glenn H. Olsen
Failure of tetracycline as a biomarker in batch-marking juvenile frogs Failure of tetracycline as a biomarker in batch-marking juvenile frogs
Recent widespread amphibian declines call for better techniques to assess population dynamics. Tetracycline as a biomarker in capture-recapture studies is one technique used successfully in fish, reptiles, and mammals. A two-phase experimental study was conducted to evaluate tetracycline as a biomarker in green frogs (Rana clamitans) and pickerel frogs (Rana palustris). In the first...
Authors
Jeffrey S. Hatfield, Paula F.P. Henry, Glenn H. Olsen, M.M. Paul, Richard S. Hammerschlag
Organochlorine contaminant exposure and reproductive success of Black-Crowned Night Herons (Nycticorax nycticorax) nesting in Baltimore Harbor, Maryland Organochlorine contaminant exposure and reproductive success of Black-Crowned Night Herons (Nycticorax nycticorax) nesting in Baltimore Harbor, Maryland
The declining size of the Baltimore Harbor black-crowned night-heron (Nycticorax nycticorax) colony has been hypothesized to be linked to polychlorinated biphenyl (PCB) exposure. In 1998, a “sample egg” was collected from 65 black-crowned night-heron nests (each containing ≥ three eggs) for contaminant analysis, and the remaining eggs in these 65 nests, plus four two-egg nests, were...
Authors
Barnett A. Rattner, P. C. McGowan, Jeff S. Hatfield, Chia-Swee Hong, S. G. Chu
Science and Products
Filter Total Items: 54
Temporal variation in bird counts within a Hawaiian rainforest Temporal variation in bird counts within a Hawaiian rainforest
We studied monthly and annual variation in density estimates of nine forest bird species along an elevational gradient in an east Maui rainforest. We conducted monthly variable circular-plot counts for 36 consecutive months along transects running downhill from timberline. Density estimates were compared by month, year, and station for all resident bird species with sizeable populations
Authors
John C. Simon, T.K. Pratt, Kim E. Berlin, James R. Kowalsky, S.G. Fancy, Jeff S. Hatfield
Behavioral effects of environmental enrichment on harbor seals (Phoca vitulina concolor) and gray seals (Halichoerus grypus) Behavioral effects of environmental enrichment on harbor seals (Phoca vitulina concolor) and gray seals (Halichoerus grypus)
Zoos and aquariums have been incorporating environmental enrichment into their animal care programs for the past 30 years to increase mental stimulation and promote natural behaviors. However, most attempts to document the effects of enrichment on animal behavior have focused on terrestrial mammals. Staff at the National Aquarium in Baltimore conducted an investigation of the behavioral...
Authors
S. A. Hunter, M. S. Bay, M. L. Martin, Jeffrey S. Hatfield
`Akohekohe response to flower availability: seasonal abundance, foraging, breeding, and molt `Akohekohe response to flower availability: seasonal abundance, foraging, breeding, and molt
We studied the relationship of flower availability to the seasonality of life history events of the `Akohekohe (Palmeria dolei), a primarily nectarivorous and endangered Hawaiian honeycreeper from montane rain forests on Maui, Hawai`i. For comparison, we also investigated temporal bird density and foraging behavior of three other competing Hawaiian honeycreepers: `Apapane (Himatione...
Authors
Kim E. Berlin, John C. Simon, T.K. Pratt, James R. Kowalsky, Jeff S. Hatfield
Water conditioning and whooping crane survival after release in Florida Water conditioning and whooping crane survival after release in Florida
About 50% of the whooping cranes (Grus americana) released in Florida die within the first year of release. Most of these deaths and those in subsequent years result from bobcat (Lynx rufus) predation. Choosing release sites in open marshes away from bobcat habitat has improved survival. We hypothesized that exposure to ponds (water conditioning) at the rearing site would encourage birds...
Authors
G.F. Gee, Jane M. Nicolich, S.A. Nesbitt, Jeff S. Hatfield, D. H. Ellis, Glenn H. Olsen
Failure of tetracycline as a biomarker in batch-marking juvenile frogs Failure of tetracycline as a biomarker in batch-marking juvenile frogs
Recent widespread amphibian declines call for better techniques to assess population dynamics. Tetracycline as a biomarker in capture-recapture studies is one technique used successfully in fish, reptiles, and mammals. A two-phase experimental study was conducted to evaluate tetracycline as a biomarker in green frogs (Rana clamitans) and pickerel frogs (Rana palustris). In the first...
Authors
Jeffrey S. Hatfield, Paula F.P. Henry, Glenn H. Olsen, M.M. Paul, Richard S. Hammerschlag
Organochlorine contaminant exposure and reproductive success of Black-Crowned Night Herons (Nycticorax nycticorax) nesting in Baltimore Harbor, Maryland Organochlorine contaminant exposure and reproductive success of Black-Crowned Night Herons (Nycticorax nycticorax) nesting in Baltimore Harbor, Maryland
The declining size of the Baltimore Harbor black-crowned night-heron (Nycticorax nycticorax) colony has been hypothesized to be linked to polychlorinated biphenyl (PCB) exposure. In 1998, a “sample egg” was collected from 65 black-crowned night-heron nests (each containing ≥ three eggs) for contaminant analysis, and the remaining eggs in these 65 nests, plus four two-egg nests, were...
Authors
Barnett A. Rattner, P. C. McGowan, Jeff S. Hatfield, Chia-Swee Hong, S. G. Chu