Thomas Custer (Former Employee)
Science and Products
Filter Total Items: 185
Migration chronology and distribution of redheads on the lower Laguna Madre, Texas
An estimated 80% of redheads (Aythya americana) winter on the Laguna Madre of southern Texas and Mexico. Because there have been profound changes in the Laguna Madre over the past three decades and the area is facing increasing industrial and recreational development, we studied the winter distribution and habitat requirements of redheads during two winters (1987-1988 and 1988-1989) on the Lower L
Authors
Christine M. Custer, T. W. Custer, P.J. Zwank
Contaminant concentrations and biomarker response in great blue heron eggs from 10 colonies on the upper Mississippi River, USA
In 1993, great blue heron (Ardea herodias; GBH) eggs were collected from 10 colonies on the upper Mississippi River (UMR). They were then artificially incubated until pipping and analyzed for mercury, selenium, and organochlorines. Livers of embryos were analyzed for hepatic microsomal ethoxyresorufin-O-dealkylase (EROD) activity and four measures of oxidative stress. Brains were measured for asym
Authors
T. W. Custer, R. K. Hines, M. J. Melancon, D. J. Hoffman, J.K. Wickliffe, J. W. Bickham, J.W. Martin, D.S. Henshel
Distribution of organochlorine contaminants in double-crested cormorant eggs and sibling embryos
Double-crested cormorant (Phalacrocorax auritus) fresh eggs and sibling embryos at pipping were collected from a polychlorinated biphenyl (PCB)-contaminated colony in Green Bay, Wisconsin, USA. Egg contents were analyzed for organochlorine (OC) contaminants, including 15 arylhydrocarbon-active PCB congeners. In order to determine the significance of tissue removal on the subsequent estimate of con
Authors
T. W. Custer, Christine M. Custer, K. L. Stromborg
Occurrence of zebra mussels in near-shore areas of western Lake Erie
Zebra mussels (Dreissena polymorpha) invaded the Great Lakes in the mid-1980s and quickly reached high densities. The objective of this study was to determine current consumption of zebra mussels by waterfowl in the Great Lakes region. Feeding Lesser Scaups (Aythya affinis), Greater Scaups (A. marila), Canvasbacks (A. valisineria), Redheads (A. americana), Buffleheads (Bucephala albeola) and Commo
Authors
Christine M. Custer, T. W. Custer
Organochlorine accumulation by sentinel mallards at the Winston-Thomas sewage treatment plant, Bloomington, Indiana
Farm-raised 12-month-old female mallards (Anas platyrhynchos) were released at the Winston-Thomas sewage treatment plant, Bloomington, Indiana. Five mallards were sacrificed at the start of the study and at approximately 10-day intervals through day 100. Concentrations of polychlorinated biphenyls (PCBs) in carcasses increased linearly with time of exposure and exceeded 16 μg/g wet weight by day 1
Authors
T. W. Custer, D. W. Sparks, S. A. Sobiech, R. K. Hines, M. J. Melancon
Cytochrome P450 and contaminant concentrations in nestling black-crowned night-herons and their interrelation with sibling embryos
Hepatic cytochrome P450-associated monooxygenase activities were measured in 11-d-old nestling black-crowned night-herons (Nycticorax nycticorax) collected from a reference site (next to Chincoteague National Wildlife Refuge, VA, USA) and three contaminated sites (Cat Island, Green Bay, WI, USA; Bair Island, San Francisco Bay, CA, USA; and West Marin Island, San Francisco Bay, CA, USA). Arylhydroc
Authors
Barnett A. Rattner, Mark J. Melancon, Thomas W. Custer, Roger L. Hothem
Radio telemetry documents 24-hour feeding activity of wintering lesser scaup
We used radio telemetry to record 198 h of feeding behavior of five Lesser Scaup (Aythya affinis) on the Indiana Harbor Canal in northwestern Indiana during January and February 1994. Lesser Scaup fed for short periods of time intermittently during each 24-h period. Lesser Scaup fed a total of 96 min during the day and 226 min during the night. They fed more between sunset and midnight (31.9% of t
Authors
Christine M. Custer, T. W. Custer, D. W. Sparks
Organochlorine accumulation by Sentinel Mallards at the Winston-Thomas sewage treatment plant, Bloomington, Indiana
Farm-raised l2-month-old female mallards (Anas platyrhynchos) were released at the Winston-Thomas sewage treatment plant, Bloomington, Indiana. Five mallards were sacrificed at the start of the study and at approximately 10-day intervals through day 100. Concentrations of polychlorinated biphenyls (PCBs) in carcasses increased linearly with time of exposure and exceeded 16 mcg/g wet weight by day
Authors
T. W. Custer, D.W. Sparks, S.A. Sobiech, R. K. Hines, M. J. Melancon
Movement patterns of wintering lesser scaup in Grand Calumet River - Indiana Harbor Canal, Indiana
Lesser scaup (Aythya affinis) winter in the Grand Calumet River-Indiana Harbor Canal (GCR-IHC) drainage into southern Lake Michigan, a polluted oasis in the highly urban and industrial corridor of northern Illinois and Indiana. The GCR-IHC is an important wintering area for lesser scaup in northwestern Indiana, especially after Lake Michigan freezes, because of the lack of other wildlife habita
Authors
Christine M. Custer, T. W. Custer, D. W. Sparks, Randy K. Hines, C.O. Kochanny
Nest initiation and clutch size of great blue herons on the Mississippi River in relation to the 1993 flood
Great Blue Heron (Ardea herodias) eggs were collected from ten colonies between Clinton, Iowa and Royalton, Minnesota on the Mississippi River in 1993, a year of record floods in the midwestern United States. In the live southernmost colonies where record flooding occurred, Great Blue Herons initiated nesting two weeks later than herons nesting in the five northernmost colonies that were less affe
Authors
T. W. Custer, R. K. Hines, Christine M. Custer
Food habits of diving ducks in the Great Lakes after the zebra mussel invasion
Zebra mussels (Dreissena polymorpha) invaded the Great Lakes in the mid-1980s and quickly reached high densities. The objective of this study was to determine current consumption of zebra mussels by waterfowl in the Great Lakes region. Feeding Lesser Scaups (Aythya affinis), Greater Scaups (A. marila), Canvasbacks (A. valisineria), Redheads (A. americana), Buffleheads (Bucephala albeola) and Commo
Authors
Christine M. Custer, T. W. Custer
Evaluation of an extendable pole-net to collect heron eggs in the canopy of tall trees
A pole, extendable from 2 to 8 m, with a nylon-mesh collecting net, was used to retrieve eggs from nests of Great Blue Herons (Ardea herodias) in the canopy of floodplain forests. A total of 200 eggs was collected for contaminant analysis from ten colonies along the upper Mississippi River during the spring of 1993. Low egg breakage (1%) and acceptable survival of embryos in an incubator to pipp
Authors
R. K. Hines, T. W. Custer
Science and Products
Filter Total Items: 185
Migration chronology and distribution of redheads on the lower Laguna Madre, Texas
An estimated 80% of redheads (Aythya americana) winter on the Laguna Madre of southern Texas and Mexico. Because there have been profound changes in the Laguna Madre over the past three decades and the area is facing increasing industrial and recreational development, we studied the winter distribution and habitat requirements of redheads during two winters (1987-1988 and 1988-1989) on the Lower L
Authors
Christine M. Custer, T. W. Custer, P.J. Zwank
Contaminant concentrations and biomarker response in great blue heron eggs from 10 colonies on the upper Mississippi River, USA
In 1993, great blue heron (Ardea herodias; GBH) eggs were collected from 10 colonies on the upper Mississippi River (UMR). They were then artificially incubated until pipping and analyzed for mercury, selenium, and organochlorines. Livers of embryos were analyzed for hepatic microsomal ethoxyresorufin-O-dealkylase (EROD) activity and four measures of oxidative stress. Brains were measured for asym
Authors
T. W. Custer, R. K. Hines, M. J. Melancon, D. J. Hoffman, J.K. Wickliffe, J. W. Bickham, J.W. Martin, D.S. Henshel
Distribution of organochlorine contaminants in double-crested cormorant eggs and sibling embryos
Double-crested cormorant (Phalacrocorax auritus) fresh eggs and sibling embryos at pipping were collected from a polychlorinated biphenyl (PCB)-contaminated colony in Green Bay, Wisconsin, USA. Egg contents were analyzed for organochlorine (OC) contaminants, including 15 arylhydrocarbon-active PCB congeners. In order to determine the significance of tissue removal on the subsequent estimate of con
Authors
T. W. Custer, Christine M. Custer, K. L. Stromborg
Occurrence of zebra mussels in near-shore areas of western Lake Erie
Zebra mussels (Dreissena polymorpha) invaded the Great Lakes in the mid-1980s and quickly reached high densities. The objective of this study was to determine current consumption of zebra mussels by waterfowl in the Great Lakes region. Feeding Lesser Scaups (Aythya affinis), Greater Scaups (A. marila), Canvasbacks (A. valisineria), Redheads (A. americana), Buffleheads (Bucephala albeola) and Commo
Authors
Christine M. Custer, T. W. Custer
Organochlorine accumulation by sentinel mallards at the Winston-Thomas sewage treatment plant, Bloomington, Indiana
Farm-raised 12-month-old female mallards (Anas platyrhynchos) were released at the Winston-Thomas sewage treatment plant, Bloomington, Indiana. Five mallards were sacrificed at the start of the study and at approximately 10-day intervals through day 100. Concentrations of polychlorinated biphenyls (PCBs) in carcasses increased linearly with time of exposure and exceeded 16 μg/g wet weight by day 1
Authors
T. W. Custer, D. W. Sparks, S. A. Sobiech, R. K. Hines, M. J. Melancon
Cytochrome P450 and contaminant concentrations in nestling black-crowned night-herons and their interrelation with sibling embryos
Hepatic cytochrome P450-associated monooxygenase activities were measured in 11-d-old nestling black-crowned night-herons (Nycticorax nycticorax) collected from a reference site (next to Chincoteague National Wildlife Refuge, VA, USA) and three contaminated sites (Cat Island, Green Bay, WI, USA; Bair Island, San Francisco Bay, CA, USA; and West Marin Island, San Francisco Bay, CA, USA). Arylhydroc
Authors
Barnett A. Rattner, Mark J. Melancon, Thomas W. Custer, Roger L. Hothem
Radio telemetry documents 24-hour feeding activity of wintering lesser scaup
We used radio telemetry to record 198 h of feeding behavior of five Lesser Scaup (Aythya affinis) on the Indiana Harbor Canal in northwestern Indiana during January and February 1994. Lesser Scaup fed for short periods of time intermittently during each 24-h period. Lesser Scaup fed a total of 96 min during the day and 226 min during the night. They fed more between sunset and midnight (31.9% of t
Authors
Christine M. Custer, T. W. Custer, D. W. Sparks
Organochlorine accumulation by Sentinel Mallards at the Winston-Thomas sewage treatment plant, Bloomington, Indiana
Farm-raised l2-month-old female mallards (Anas platyrhynchos) were released at the Winston-Thomas sewage treatment plant, Bloomington, Indiana. Five mallards were sacrificed at the start of the study and at approximately 10-day intervals through day 100. Concentrations of polychlorinated biphenyls (PCBs) in carcasses increased linearly with time of exposure and exceeded 16 mcg/g wet weight by day
Authors
T. W. Custer, D.W. Sparks, S.A. Sobiech, R. K. Hines, M. J. Melancon
Movement patterns of wintering lesser scaup in Grand Calumet River - Indiana Harbor Canal, Indiana
Lesser scaup (Aythya affinis) winter in the Grand Calumet River-Indiana Harbor Canal (GCR-IHC) drainage into southern Lake Michigan, a polluted oasis in the highly urban and industrial corridor of northern Illinois and Indiana. The GCR-IHC is an important wintering area for lesser scaup in northwestern Indiana, especially after Lake Michigan freezes, because of the lack of other wildlife habita
Authors
Christine M. Custer, T. W. Custer, D. W. Sparks, Randy K. Hines, C.O. Kochanny
Nest initiation and clutch size of great blue herons on the Mississippi River in relation to the 1993 flood
Great Blue Heron (Ardea herodias) eggs were collected from ten colonies between Clinton, Iowa and Royalton, Minnesota on the Mississippi River in 1993, a year of record floods in the midwestern United States. In the live southernmost colonies where record flooding occurred, Great Blue Herons initiated nesting two weeks later than herons nesting in the five northernmost colonies that were less affe
Authors
T. W. Custer, R. K. Hines, Christine M. Custer
Food habits of diving ducks in the Great Lakes after the zebra mussel invasion
Zebra mussels (Dreissena polymorpha) invaded the Great Lakes in the mid-1980s and quickly reached high densities. The objective of this study was to determine current consumption of zebra mussels by waterfowl in the Great Lakes region. Feeding Lesser Scaups (Aythya affinis), Greater Scaups (A. marila), Canvasbacks (A. valisineria), Redheads (A. americana), Buffleheads (Bucephala albeola) and Commo
Authors
Christine M. Custer, T. W. Custer
Evaluation of an extendable pole-net to collect heron eggs in the canopy of tall trees
A pole, extendable from 2 to 8 m, with a nylon-mesh collecting net, was used to retrieve eggs from nests of Great Blue Herons (Ardea herodias) in the canopy of floodplain forests. A total of 200 eggs was collected for contaminant analysis from ten colonies along the upper Mississippi River during the spring of 1993. Low egg breakage (1%) and acceptable survival of embryos in an incubator to pipp
Authors
R. K. Hines, T. W. Custer