Sam Droege
Sam is a Wildlife Biologist at the Eastern Ecological Science Center in Laurel, MD.
Sam has coordinated the North American Breeding Bird Survey Program, developed the North American Amphibian Monitoring Program, the BioBlitz, Cricket Crawl, and FrogwatchUSA programs and worked on the design and evaluation of monitoring programs. Currently he is developing an inventory and monitoring program for native bees, online identification guides for North American bees at discoverlife.org, and reviving the North American Bird Phenology Program.
Education and Certifications
M.S. from State University of New York – Syracuse
B.S. from University of Maryland
Science and Products
Filter Total Items: 71
A unified strategy for monitoring changes in abundance of birds associated with North American tidal marshes
An effective approach to species conservation involves efforts to prevent species from becoming threatened with extinction before they become listed as endangered. Standardized monitoring efforts provide the data necessary to estimate population trajectories of many species so that management agencies can identify declining species before they reach the point of endangerment. Species...
Authors
C.J. Conway, Sam Droege
Tidal marshes: A global perspective on the evolution and conservation of their terrestrial vertebrates
Globally, tidal marshes are found in small pockets or narrow bands totaling only approximately 45,000 square kilometers. The combination of salinity, low floristic and structural complexity, and regular tidal inundation, as well as unpredictable catastrophic flooding, provides a unique selective environment that shapes local adaptations, including those that are morphological...
Authors
Russell Greenberg, Jesus Maldonado, Sam Droege, M.V. McDonald
Adventive Hylaeus (Spatulariella Popov) in the New World (Hymenoptera : Apoidea : Colletidae)
No abstract available.
Authors
J.S. Ascher, P. Ganibino, Sam Droege
The potential conservation value of unmowed powerline strips for native bees
The land area covered by powerline easements in the United States exceeds the area of almost all national parks, including Yellowstone. In parts of Europe and the US, electric companies have altered their land management practices from periodic mowing to extraction of tall vegetation combined with the use of selective herbicides. To investigate whether this alternate management practice...
Authors
K.N. Russell, H. Ikerd, Sam Droege
Large-scale habitat associations of four desert anurans in Big Bend National Park, Texas
We used night driving to examine large scale habitat associations of four common desert anurans in Big Bend National Park, Texas. We examined association of soil types and vegetation communities with abundance of Couch's Spadefoots (Scaphiopus couchii), Red-spotted Toads (Bufo punctatus), Texas Toads (Bufo speciosus), and Western Green Toads (Bufo debilis). All four species were...
Authors
Gage H. Dayton, R.E. Jung, Sam Droege
Distribution, abundance, and habitat affinities of the Coastal Plain Swamp Sparrow
We examined the distribution and abundance of the Coastal Plain Swamp Sparrow (Melospiza georgiana nigrescens) at previously occupied sites and points within potential habitat. We found Swamp Sparrows throughout their formerly documented range except in southern Chesapeake Bay. Swamp Sparrows were most common in the Mullica River region of New Jersey where we detected individuals at 78%...
Authors
J.S. Beadell, R. Greenberg, Sam Droege, Andy Royle
Estimating site occupancy rates when detection probabilities are less than one
Nondetection of a species at a site does not imply that the species is absent unless the probability of detection is 1. We propose a model and likelihood-based method for estimating site occupancy rates when detection probabilities are 1. The model provides a flexible framework enabling covariate information to be included and allowing for missing observations. Via computer simulation...
Authors
D.I. MacKenzie, James D. Nichols, G.B. Lachman, Sam Droege, Andy Royle, Catherine A. Langtimm
FrogwatchUSA
full text: Frogs and toads are perhaps the most approachable and available of all our wildlife. In many, if not most places, they are abundant. In wetter parts of the East, almost anyone outside on a warm rainy night in spring will hear their dream-like calls, bellows, trills and snores. Even in the deserts of the Southwest, a nocturnal trip after a summer monsoon will yield toads moving...
Authors
Sam Droege
An evaluation of population index and estimation techniques for tadpoles in desert pools
Using visual (VI) and dip net indices (DI) and double-observer (DOE), removal (RE), and neutral red dye capture-recapture (CRE) estimates, we counted, estimated, and censused Couch's spadefoot (Scaphiopus couchii) and canyon treefrog (Hyla arenicolor) tadpole populations in Big Bend National Park, Texas. Initial dye experiments helped us determine appropriate dye concentrations and...
Authors
Robin E. Jung, Gage H. Dayton, Stephen J. Williamson, John R. Sauer, Sam Droege
Evaluation of canoe surveys for anurans along the Rio Grande in Big Bend National Park, Texas
Surveys for amphibians along large rivers pose monitoring and sampling problems. We used canoes at night to spotlight and listen for anurans along four stretches of the Rio Grande in Big Bend National Park, Texas, in 1998 and 1999. We explored temporal and spatial variation in amphibian counts and species richness and assessed relationships between amphibian counts and environmental...
Authors
Robin E. Jung, K. E. Bonine, M. L. Rosenshield, A. de la Reza, Sandy Raimondo, Sam Droege
Science and Products
Filter Total Items: 71
A unified strategy for monitoring changes in abundance of birds associated with North American tidal marshes
An effective approach to species conservation involves efforts to prevent species from becoming threatened with extinction before they become listed as endangered. Standardized monitoring efforts provide the data necessary to estimate population trajectories of many species so that management agencies can identify declining species before they reach the point of endangerment. Species...
Authors
C.J. Conway, Sam Droege
Tidal marshes: A global perspective on the evolution and conservation of their terrestrial vertebrates
Globally, tidal marshes are found in small pockets or narrow bands totaling only approximately 45,000 square kilometers. The combination of salinity, low floristic and structural complexity, and regular tidal inundation, as well as unpredictable catastrophic flooding, provides a unique selective environment that shapes local adaptations, including those that are morphological...
Authors
Russell Greenberg, Jesus Maldonado, Sam Droege, M.V. McDonald
Adventive Hylaeus (Spatulariella Popov) in the New World (Hymenoptera : Apoidea : Colletidae)
No abstract available.
Authors
J.S. Ascher, P. Ganibino, Sam Droege
The potential conservation value of unmowed powerline strips for native bees
The land area covered by powerline easements in the United States exceeds the area of almost all national parks, including Yellowstone. In parts of Europe and the US, electric companies have altered their land management practices from periodic mowing to extraction of tall vegetation combined with the use of selective herbicides. To investigate whether this alternate management practice...
Authors
K.N. Russell, H. Ikerd, Sam Droege
Large-scale habitat associations of four desert anurans in Big Bend National Park, Texas
We used night driving to examine large scale habitat associations of four common desert anurans in Big Bend National Park, Texas. We examined association of soil types and vegetation communities with abundance of Couch's Spadefoots (Scaphiopus couchii), Red-spotted Toads (Bufo punctatus), Texas Toads (Bufo speciosus), and Western Green Toads (Bufo debilis). All four species were...
Authors
Gage H. Dayton, R.E. Jung, Sam Droege
Distribution, abundance, and habitat affinities of the Coastal Plain Swamp Sparrow
We examined the distribution and abundance of the Coastal Plain Swamp Sparrow (Melospiza georgiana nigrescens) at previously occupied sites and points within potential habitat. We found Swamp Sparrows throughout their formerly documented range except in southern Chesapeake Bay. Swamp Sparrows were most common in the Mullica River region of New Jersey where we detected individuals at 78%...
Authors
J.S. Beadell, R. Greenberg, Sam Droege, Andy Royle
Estimating site occupancy rates when detection probabilities are less than one
Nondetection of a species at a site does not imply that the species is absent unless the probability of detection is 1. We propose a model and likelihood-based method for estimating site occupancy rates when detection probabilities are 1. The model provides a flexible framework enabling covariate information to be included and allowing for missing observations. Via computer simulation...
Authors
D.I. MacKenzie, James D. Nichols, G.B. Lachman, Sam Droege, Andy Royle, Catherine A. Langtimm
FrogwatchUSA
full text: Frogs and toads are perhaps the most approachable and available of all our wildlife. In many, if not most places, they are abundant. In wetter parts of the East, almost anyone outside on a warm rainy night in spring will hear their dream-like calls, bellows, trills and snores. Even in the deserts of the Southwest, a nocturnal trip after a summer monsoon will yield toads moving...
Authors
Sam Droege
An evaluation of population index and estimation techniques for tadpoles in desert pools
Using visual (VI) and dip net indices (DI) and double-observer (DOE), removal (RE), and neutral red dye capture-recapture (CRE) estimates, we counted, estimated, and censused Couch's spadefoot (Scaphiopus couchii) and canyon treefrog (Hyla arenicolor) tadpole populations in Big Bend National Park, Texas. Initial dye experiments helped us determine appropriate dye concentrations and...
Authors
Robin E. Jung, Gage H. Dayton, Stephen J. Williamson, John R. Sauer, Sam Droege
Evaluation of canoe surveys for anurans along the Rio Grande in Big Bend National Park, Texas
Surveys for amphibians along large rivers pose monitoring and sampling problems. We used canoes at night to spotlight and listen for anurans along four stretches of the Rio Grande in Big Bend National Park, Texas, in 1998 and 1999. We explored temporal and spatial variation in amphibian counts and species richness and assessed relationships between amphibian counts and environmental...
Authors
Robin E. Jung, K. E. Bonine, M. L. Rosenshield, A. de la Reza, Sandy Raimondo, Sam Droege