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: 72
Long-term decline and short-term crash of the once abundant Rusty Blackbird Long-term decline and short-term crash of the once abundant Rusty Blackbird
The Rusty Blackbird (Euphagus carolinus), a formerly common breeding species of boreal wetlands, has exhibited the most marked decline of any North American landbird. North American Breeding Bird Survey (BBS) trends in abundance are estimated to be -12.5% / yr over the last 40 years, which is tantamount to a >95% cumulative decline. Trends in abundance calculated from Christmas Bird...
Authors
R. Greenberg, P. Blancher, D. Niven, Sam Droege
A unified strategy for monitoring changes in abundance of birds associated with North American tidal marshes 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 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) Adventive Hylaeus (Spatulariella Popov) in the New World (Hymenoptera : Apoidea : Colletidae)
No abstract available.
Authors
J.S. Ascher, P. Ganibino, Sam Droege
Evaluating calling surveys Evaluating calling surveys
No abstract available.
Authors
Sam Droege, P. Eagle
The potential conservation value of unmowed powerline strips for native bees 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 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 Dayton, R.E. Jung, Sam Droege
Distribution, abundance, and habitat affinities of the Coastal Plain Swamp Sparrow 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. Beadell, R. Greenberg, Sam Droege, J. Andrew Royle
Leaf litter bags as an index to populations of northern two-lined salamanders (Eurycea bislineata) Leaf litter bags as an index to populations of northern two-lined salamanders (Eurycea bislineata)
Concern about recent amphibian declines has led to research on amphibian populations, but few statistically tested, standardized methods of counting amphibians exist. We tested whether counts of northern two-lined salamander larvae (Eurycea bislineata) sheltered in leaf litter bags--a relatively new, easily replicable survey technique--had a linear correlation to total number of larvae...
Authors
R.J. Chalmers, Sam Droege
Estimating site occupancy rates when detection probabilities are less than one 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, J.D. Nichols, G.B. Lachman, Sam Droege, J. Andrew Royle, C.A. Langtimm
An evaluation of population index and estimation techniques for tadpoles in desert pools 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 Jung, Gage Dayton, Stephen Williamson, John R. Sauer, Sam Droege
Science and Products
Filter Total Items: 72
Long-term decline and short-term crash of the once abundant Rusty Blackbird Long-term decline and short-term crash of the once abundant Rusty Blackbird
The Rusty Blackbird (Euphagus carolinus), a formerly common breeding species of boreal wetlands, has exhibited the most marked decline of any North American landbird. North American Breeding Bird Survey (BBS) trends in abundance are estimated to be -12.5% / yr over the last 40 years, which is tantamount to a >95% cumulative decline. Trends in abundance calculated from Christmas Bird...
Authors
R. Greenberg, P. Blancher, D. Niven, Sam Droege
A unified strategy for monitoring changes in abundance of birds associated with North American tidal marshes 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 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) Adventive Hylaeus (Spatulariella Popov) in the New World (Hymenoptera : Apoidea : Colletidae)
No abstract available.
Authors
J.S. Ascher, P. Ganibino, Sam Droege
Evaluating calling surveys Evaluating calling surveys
No abstract available.
Authors
Sam Droege, P. Eagle
The potential conservation value of unmowed powerline strips for native bees 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 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 Dayton, R.E. Jung, Sam Droege
Distribution, abundance, and habitat affinities of the Coastal Plain Swamp Sparrow 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. Beadell, R. Greenberg, Sam Droege, J. Andrew Royle
Leaf litter bags as an index to populations of northern two-lined salamanders (Eurycea bislineata) Leaf litter bags as an index to populations of northern two-lined salamanders (Eurycea bislineata)
Concern about recent amphibian declines has led to research on amphibian populations, but few statistically tested, standardized methods of counting amphibians exist. We tested whether counts of northern two-lined salamander larvae (Eurycea bislineata) sheltered in leaf litter bags--a relatively new, easily replicable survey technique--had a linear correlation to total number of larvae...
Authors
R.J. Chalmers, Sam Droege
Estimating site occupancy rates when detection probabilities are less than one 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, J.D. Nichols, G.B. Lachman, Sam Droege, J. Andrew Royle, C.A. Langtimm
An evaluation of population index and estimation techniques for tadpoles in desert pools 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 Jung, Gage Dayton, Stephen Williamson, John R. Sauer, Sam Droege