Thomas Custer (Former Employee)
Science and Products
Filter Total Items: 185
Exposure to insecticides of brushland wildlife within the lower Rio Grande valley Texas USA
Brushland wildlife within the Lower Rio Grande Valley of south Texas were studied following applications of eleven insecticides to nearby sugarcane or cotton fields. During the study no wildlife were found dead. Mean brain acetycholinesterase (AChE) activity of great-tailed grackles (Quiscalus mexicanus) and mourning doves (Zenaida microura) was significantly lower than controls following applicat
Authors
T. W. Custer, C. A. Mitchell
Exposure to insecticides of brushland wildlife within the Lower Rio Grande Valley, Texas, USA
Brushland wildlife within the Lower Rio Grande Valley of south Texas were studied following applications of eleven insecticides to nearby sugarcane or cotton fields. During the study no wildlife were found dead. Mean brain acetylcholinesterase (AChE) activity of great-tailed grackles (Quiscalus mexicanus) and mourning doves (Zenaida macroura) was significantly lower than controls following applica
Authors
T. W. Custer, C. A. Mitchell
Energy budget and prey requirements of breeding lapland longspurs Calcarius lapponicus near Barrow Alaska, U.S.A.
Breeding Lapland longspurs, Calcarius lapponicus, near Barrow, Alaska, have relatively constant energy demands throughout the summer; the average estimated daily energy budgets (DEBs) were 132 and 118 kJ for the male and female. Thermoregulation accounted consistently for one-quarter to one-third of the total DEB. Flight in the male and incubation in the female were major components of the DEB ear
Authors
T. W. Custer, R. G. Osborn, F.A. Pitelka, J.A. Gessaman
Hatching success of Caspian terns nesting in the lower Laguna Madre, Texas, USA
The average clutch size of Caspian Terns nesting in a colony in the Lower Laguna Madre near Laguna Vista, Texas, USA in 1984 was 1.9 eggs per nest. Using the Mayfield method for calculating success, one egg hatched in 84.1% of the nests and 69.8% of the eggs laid hatched. These hatching estimates are as high or higher than estimates from colonies in other areas.
Authors
C. A. Mitchell, T. W. Custer
Reproductive success and heavy metal contamination in Rhode Island common terns
Common tern cIutch size, reproductive success and growth of young recorded from an abandoned barge on the Providence River, an area of heavy metal contamination, were equal to, or greater than, .from less contaminated areas. Concentrations of copper and zinc were higher in livers of nestling terns from the Providence River than from other, less contaminated, areas. However, concentrations of magne
Authors
T. W. Custer, J. C. Franson, John F. Moore, J.E. Myers
Organochlorine concentrations in prefledging common terns Sterna hirundo at three Rhode Island USA colonies
Concentrations of DDE, polychlorinated biphenyls (PCBs), and polychlorinated diphenyl ethers (PCDPEs) in carcasses of prefledging Common Terns (Sterna hirundo) at three Rhode Island colonies support the hypothesis that local contamination is responsible for among-colony differences observed in eggs in an earlier study. The highest concentrations of DDE and PCBs (mean=0.24 and 2.8 ppm wet weight) w
Authors
T. W. Custer, C. M. Bunck, C.L. Stafford
Effects of wildlife of ethyl and methyl parathion applied to California USA rice fields
Selected rice fields on the Sacramento National Wildlife Refuge Complex were aerially sprayed one time during May or June 1982 with either ethyl (0.11 kg Al/ha) or methyl (0.84 kg AI/ha) parathion for control of tadpole shrimp, Triops longicaudatus. No sick or dead vertebrate wildlife were found or adjacent to the treated rice fields after spraying. Specimens of the following birds and mammals wer
Authors
T. W. Custer, E. F. Hill, H. M. Ohlendorf
Reproduction and organochlorine contaminants in terns at San Diego Bay
In 1981, we studied Caspian Terns (Sterna caspia) and Elegant Terns (S. elegans) nesting at the south end of San Diego Bay, California. Randomly collected Caspian Tern eggs contained signficantly (P < 0.05) higher mean concentrations of DDE (9.30 ppm) than did Elegant Tern eggs (3.79 ppm). DDE may have had an adverse effect on Caspian Tern reproduction but the relationship between hatching success
Authors
H. M. Ohlendorf, F.C. Schaffner, T. W. Custer, C. J. Stafford
Organochlorines and mercury in California coastal terns and herons
No abstract available.
Authors
H. M. Ohlendorf, T. W. Custer, Roy W. Lowe, E. Cromartie
Organochlorine concentrations in prefledging common terns at three Rhode Island colonies
Concentrations of DDE, polychlorinated biphenyls (PCBs), and polychlorinated diphenyl ethers (PCDPEs) in carcasses of prefledging Common Terns (Sterna hirundo) at three Rhode Island colonies support the hypothesis that local contamination is responsible for among-colony differences observed in eggs in an earlier study. The highest concentrations of DDE and PCBs (mean = 0.24 and 2.8 ppm wet weight)
Authors
T. W. Custer, C. M. Bunck, C. J. Stafford
Effects on wildlife of ethyl and methyl parathion applied to California rice fields
Selected rice fields on the Sacramento National Wildlife Refuge Complex were aerially sprayed one time during May or June 1982 with either ethyl (0.11 kg Al/ha) or methyl (0.84 kg AI/ha) parathion for control of tadpole shrimp, Triops longicaudatus. No sick or dead vertebrate wildlife were found or adjacent to the treated rice fields after spraying. Specimens of the following birds and mammals wer
Authors
Thomas W. Custer, Elwood F. Hill, Harry M. Ohlendorf
Tissue lead distribution and hematologic effects in American kestrels (Falco sparverius) fed biologically incorporated lead
American kestrels were fed a diet containing 0.5, 120, 212, and 448 ppm (dry wt) biologically incorporated lead (Pb) for 60 days. The diet consisted of homogenized 4-wk-old cockerels raised on feed mixed with and without lead. No kestrels died and weights did not differ among treatment groups. The control group (0.5 ppm Pb) had the lowest mean concentration of lead and the high dietary group had t
Authors
T. W. Custer, J. C. Franson, O. H. Pattee
Science and Products
Filter Total Items: 185
Exposure to insecticides of brushland wildlife within the lower Rio Grande valley Texas USA
Brushland wildlife within the Lower Rio Grande Valley of south Texas were studied following applications of eleven insecticides to nearby sugarcane or cotton fields. During the study no wildlife were found dead. Mean brain acetycholinesterase (AChE) activity of great-tailed grackles (Quiscalus mexicanus) and mourning doves (Zenaida microura) was significantly lower than controls following applicat
Authors
T. W. Custer, C. A. Mitchell
Exposure to insecticides of brushland wildlife within the Lower Rio Grande Valley, Texas, USA
Brushland wildlife within the Lower Rio Grande Valley of south Texas were studied following applications of eleven insecticides to nearby sugarcane or cotton fields. During the study no wildlife were found dead. Mean brain acetylcholinesterase (AChE) activity of great-tailed grackles (Quiscalus mexicanus) and mourning doves (Zenaida macroura) was significantly lower than controls following applica
Authors
T. W. Custer, C. A. Mitchell
Energy budget and prey requirements of breeding lapland longspurs Calcarius lapponicus near Barrow Alaska, U.S.A.
Breeding Lapland longspurs, Calcarius lapponicus, near Barrow, Alaska, have relatively constant energy demands throughout the summer; the average estimated daily energy budgets (DEBs) were 132 and 118 kJ for the male and female. Thermoregulation accounted consistently for one-quarter to one-third of the total DEB. Flight in the male and incubation in the female were major components of the DEB ear
Authors
T. W. Custer, R. G. Osborn, F.A. Pitelka, J.A. Gessaman
Hatching success of Caspian terns nesting in the lower Laguna Madre, Texas, USA
The average clutch size of Caspian Terns nesting in a colony in the Lower Laguna Madre near Laguna Vista, Texas, USA in 1984 was 1.9 eggs per nest. Using the Mayfield method for calculating success, one egg hatched in 84.1% of the nests and 69.8% of the eggs laid hatched. These hatching estimates are as high or higher than estimates from colonies in other areas.
Authors
C. A. Mitchell, T. W. Custer
Reproductive success and heavy metal contamination in Rhode Island common terns
Common tern cIutch size, reproductive success and growth of young recorded from an abandoned barge on the Providence River, an area of heavy metal contamination, were equal to, or greater than, .from less contaminated areas. Concentrations of copper and zinc were higher in livers of nestling terns from the Providence River than from other, less contaminated, areas. However, concentrations of magne
Authors
T. W. Custer, J. C. Franson, John F. Moore, J.E. Myers
Organochlorine concentrations in prefledging common terns Sterna hirundo at three Rhode Island USA colonies
Concentrations of DDE, polychlorinated biphenyls (PCBs), and polychlorinated diphenyl ethers (PCDPEs) in carcasses of prefledging Common Terns (Sterna hirundo) at three Rhode Island colonies support the hypothesis that local contamination is responsible for among-colony differences observed in eggs in an earlier study. The highest concentrations of DDE and PCBs (mean=0.24 and 2.8 ppm wet weight) w
Authors
T. W. Custer, C. M. Bunck, C.L. Stafford
Effects of wildlife of ethyl and methyl parathion applied to California USA rice fields
Selected rice fields on the Sacramento National Wildlife Refuge Complex were aerially sprayed one time during May or June 1982 with either ethyl (0.11 kg Al/ha) or methyl (0.84 kg AI/ha) parathion for control of tadpole shrimp, Triops longicaudatus. No sick or dead vertebrate wildlife were found or adjacent to the treated rice fields after spraying. Specimens of the following birds and mammals wer
Authors
T. W. Custer, E. F. Hill, H. M. Ohlendorf
Reproduction and organochlorine contaminants in terns at San Diego Bay
In 1981, we studied Caspian Terns (Sterna caspia) and Elegant Terns (S. elegans) nesting at the south end of San Diego Bay, California. Randomly collected Caspian Tern eggs contained signficantly (P < 0.05) higher mean concentrations of DDE (9.30 ppm) than did Elegant Tern eggs (3.79 ppm). DDE may have had an adverse effect on Caspian Tern reproduction but the relationship between hatching success
Authors
H. M. Ohlendorf, F.C. Schaffner, T. W. Custer, C. J. Stafford
Organochlorines and mercury in California coastal terns and herons
No abstract available.
Authors
H. M. Ohlendorf, T. W. Custer, Roy W. Lowe, E. Cromartie
Organochlorine concentrations in prefledging common terns at three Rhode Island colonies
Concentrations of DDE, polychlorinated biphenyls (PCBs), and polychlorinated diphenyl ethers (PCDPEs) in carcasses of prefledging Common Terns (Sterna hirundo) at three Rhode Island colonies support the hypothesis that local contamination is responsible for among-colony differences observed in eggs in an earlier study. The highest concentrations of DDE and PCBs (mean = 0.24 and 2.8 ppm wet weight)
Authors
T. W. Custer, C. M. Bunck, C. J. Stafford
Effects on wildlife of ethyl and methyl parathion applied to California rice fields
Selected rice fields on the Sacramento National Wildlife Refuge Complex were aerially sprayed one time during May or June 1982 with either ethyl (0.11 kg Al/ha) or methyl (0.84 kg AI/ha) parathion for control of tadpole shrimp, Triops longicaudatus. No sick or dead vertebrate wildlife were found or adjacent to the treated rice fields after spraying. Specimens of the following birds and mammals wer
Authors
Thomas W. Custer, Elwood F. Hill, Harry M. Ohlendorf
Tissue lead distribution and hematologic effects in American kestrels (Falco sparverius) fed biologically incorporated lead
American kestrels were fed a diet containing 0.5, 120, 212, and 448 ppm (dry wt) biologically incorporated lead (Pb) for 60 days. The diet consisted of homogenized 4-wk-old cockerels raised on feed mixed with and without lead. No kestrels died and weights did not differ among treatment groups. The control group (0.5 ppm Pb) had the lowest mean concentration of lead and the high dietary group had t
Authors
T. W. Custer, J. C. Franson, O. H. Pattee