Daniel Twedt, Ph.D.
Biography
Daniel J. Twedt received graduate degrees from Western Kentucky and North Dakota State University for his work on starling and yellow-headed blackbird ecology, respectively. For the past 20+ years, Dr. Twedt has been a research wildlife biologist with the USGS Patuxent Wildlife Research Center, stationed in Vicksburg, MS and Memphis, TN. During this time, his research has focused on avian ecology within bottomland hardwood forests, including bird response to forest restoration and silvicultural management, and assessment of alternative restoration and management techniques. Ongoing projects address forest structure and bird response to silvicultural prescriptions targeting wildlife in bottomland hardwoods, survival and productivity of birds in bottomland forests, and landscape scale integration of national land cover and forest inventory databases for assessment of bird distribution and abundance.
My published papers and PDF copies of poster presentations are available at: https://www.researchgate.net/profile/Daniel_Twedt
Science and Products
Bird Habitat Needs in the Mississippi Alluvial Valley
Historically the Mississippi Alluvial Valley (MAV) was predominantly bottomland hardwood forest and most birds of conservation concern depend on bottomland hardwood forest. Past conservation planning has focused on habitat objectives with presumption that bird population goals would be met by habitat provision.
Monitoring Birds in National Parks of the Gulf Coast Network
The Challenge: Avian monitoring within the Gulf Coast Network of the National Park Service is challenged to provide valid quantitative data on bird populations within park boundaries with limited financial input. Thus, citizen science (volunteer) bird monitoring has been proposed to achieve reliable estimates of bird populations and to assess the effects of habitat change and temporal dynamics...
Forest Structure Resulting from ‘Wildlife Forestry Silviculture’
Wildlife forestry is management of forest resources, within sites and across landscapes, to provide sustainable, desirable habitat conditions for all forest-dependent (silvicolous) fauna while concurrently yielding economically viable, quality timber products. In practice, however, management decisions associated with wildlife forestry often reflect a desire to provide suitable habitat for...
Mammals
Our science portfolio includes the study and management of mammal populations, which can require the use of methods and analysis that incorporate the difficulty in detecting them – picture how hard it is to count and identify bats at dusk or estimate the number of mountain lions in an area.
Forests
Our nation’s forests serve many purposes including source of timber, habitat for wildlife, and a place for people to recreate. Our scientists seek to understand how forests can serve all these functions by answering such questions as, “How do forests managed for timber harvest and bird habitat affect the bat populations of the forest?” and “How can hiking trails be designed to minimize impacts...
Breeding Birds
Patuxent science expands our understanding of the ecological relationships between breeding bird communities and their habitats. For example, Patuxent scientists follow structured decision-making principles to optimize the management of fresh-water and salt-marsh habitats to benefit wetland bird communities. Following pioneering studies documenting the effects of forest fragmentation on...
Bats in Forests Managed for Wildlife
The Challenge: Within the Mississippi Alluvial Valley (MAV), forest managers may prescribe variable retention silvicultural treatments within bottomland hardwood forests on public lands to improve forest conditions (i.e., structural heterogeneity, species composition, and senescence) for priority wildlife species. This is referred to as wildlife-forestry silviculture. However, concerns have...
Conservation–Protection of forests for wildlife in the Mississippi Alluvial Valley
The nearly ubiquitous bottomland hardwood forests that historically dominated the Mississippi Alluvial Valley have been greatly reduced in area. In addition, changes in hydrology and forest management have altered the structure and composition of the remaining forests. To ameliorate the detrimental impact of these changes on wildlife, conservation...
Elliott, A. Blaine; Mini, Anne E.; McKnight, S. Keith; Twedt, Daniel J. Influence of forest harvest severity and time since perturbation on conservation of North American birds
I calculated avian conservation scores, based on published quantitative assessment of bird presence (typically relative abundance) and regional Partners in Flight conservation concern score of each species. I related these avian conservation scores to severity of forest perturbation (i.e., % retention) and number of years since perturbation for...
Twedt, Daniel J. Rapid adoption of nestboxes by Prothonotary Warblers (Protonotaria citrea) in mesic deciduous forest
Breeding territory selection in Prothonotary Warblers (Protonotaria citrea (Boddaert, 1783)) is thought to hinge on standing water, with a strong preference for low-lying areas prone to seasonal flooding. However, we have observed this species nesting in much drier areas than previously reported. We recently initiated a study of the Carolina...
Mueller, Alexander J; Twedt, Daniel J.; Bowers, E Keith Consistency counts: Modeling the effects of a change in protocol on Breeding Bird Survey counts
Analysis of North American Breeding Bird Survey (BBS) data requires controls for factors that influence detectability of birds along survey routes. Identifying factors that influence the counting process and incorporating them into analyses is a primary means of limiting bias in estimates of population change. Twedt (2015) implemented an...
Sauer, John R.; Link, William A.; Ziolkowski, David; Pardieck, Keith L.; Twedt, Daniel J. Bat community response to silvicultural treatments in bottomland hardwood forests managed for wildlife in the Mississippi Alluvial Valley
Silvicultural treatments (e.g., selective timber harvests) that are prescribed to promote wildlife habitat are intended to alter the physical structure of forests to achieve conditions deemed beneficial for wildlife. Such treatments have been advocated for management of bottomland hardwood forests on public conservation lands in the Mississippi...
Ketzler, Loraine P.; Comer, Christopher E.; Twedt, Daniel J. North American Breeding Bird Survey in Mississippi
Does it seem like you are hearing fewer Northern Bobwhite (Colinus virginianus) calls in recent years than you remember when you were younger? Conversely, have you also noticed hearing more “cooing” of Eurasian Collared-Doves (Streptopelia decaocto)? Do such experiences reflect changes in bird populations or are they false impressions? Well,...
Twedt, Daniel J.; Pardieck, Keith L. Nocturnal insect availability in bottomland hardwood forests managed for wildlife in the Mississippi Alluvial Valley
Silviculture used to alter forest structure and thereby enhance wildlife habitat has been advocated for bottomland hardwood forest management on public conservation lands in the Mississippi Alluvial Valley. Although some songbirds respond positively to these management actions to attain desired forest conditions for wildlife, the response of other...
Ketzler, Loraine P.; Christopher Comer; Twedt, Daniel J. Breeding birds in managed forests on public conservation lands in the Mississippi Alluvial Valley
Managers of public conservation lands in the Mississippi Alluvial Valley have implemented forest management strategies to improve bottomland hardwood habitat for target wildlife species. Through implementation of various silvicultural practices, forest managers have sought to attain forest structural conditions (e.g., canopy cover, basal area...
Twedt, Daniel J.; Wilson, R. Randy Object-based forest classification to facilitate landscape-scale conservation in the Mississippi Alluvial Valley
The Mississippi Alluvial Valley is a floodplain along the southern extent of the Mississippi River extending from southern Missouri to the Gulf of Mexico. This area once encompassed nearly 10 million ha of floodplain forests, most of which has been converted to agriculture over the past two centuries. Conservation programs in this region revolve...
Mitchell, Michael; Wilson, R. Randy; Twedt, Daniel J.; Mini, Anne E.; James, J. Dale Forest structure of oak plantations after silvicultural treatment to enhance habitat for wildlife
During the past 30 years, thousands of hectares of oak-dominated bottomland hardwood plantations have been planted on agricultural fields in the Mississippi Alluvial Valley. Many of these plantations now have closed canopies and sparse understories. Silvicultural treatments could create a more heterogeneous forest structure, with canopy gaps and...
Schweitzer, Callie Jo; Clatterbuck, Wayne K.; Oswalt, Christopher M.; Twedt, Daniel J.; Phillip, Cherrie-Lee P.; Guilfoyle, Michael P.; Wilson, R. Randy Flight feather molt in Yellow-headed Blackbirds (Xanthocephalus xanthocephalus) in North Dakota
Yellow-headed Blackbirds (Xanthocephalus xanthocephalus) in central North Dakota undergo prebasic molt or prejuvenile molt during late summer. Nestling Yellow-headed Blackbirds initiate a complete prejuvenile molt, grow their primary and secondary regimes in about 40 days, completing molt after they leave the nest by the first week in August....
Twedt, Daniel J.; Linz, George M. Estimating regional landbird populations from enhanced North American Breeding Bird Surveys
Estimating the size of bird populations is central to effective conservation planning and prudent management. I updated estimated regional bird populations for the East Gulf Coastal Plain of Mississippi using data from 275 North American Breeding Bird Surveys from 2009 to 2013. However, regional bird populations estimated from count surveys of...
Twedt, Daniel J.