The effects of estrogen on the reproductive tract involve cell proliferation, migration, and diff... more The effects of estrogen on the reproductive tract involve cell proliferation, migration, and differentiation, which need to be well coordinated. Polypeptide growth factors are believed to play a vital role in a number of these cellular processes. Among the growth factors now documented to be associated with estrogen action are epidermal growth factor, transforming growth factor-alpha (TGF alpha), transforming growth factor-beta 1 (TGF beta 1), TGF beta 2, TGF beta 3, and insulin-like growth factor-I (IGF-I). Platelet-derived growth factors (PDGFs) are also potent mitogens, which consist of two peptide chains, denoted A and B, that dimerize to isoforms (PDGF-AA, -AB, and -BB) which differ in their functional properties, secretory behavior, receptor binding, and physiological effects. To study the role of the PDGF-A and -B chains and the PDGF receptor subunits, alpha and beta, during estrogen action in the mouse reproductive tract, time-dependent changes in the expression of these genes were examined by Northern and in situ RNA analyses and by immunohistochemistry after a single treatment of immature CD-1 (17- to 19-day-old) mice with the synthetic estrogen, diethylstilbestrol (DES). Our results demonstrate estrogen modulation of the expression of messenger RNA (mRNA) and protein for the PDGF ligands and receptors in both the uterus and vagina of the mouse. Northern and in situ RNA analyses demonstrate time-dependent estrogen induction of the mRNA levels for these genes in both tissues within 3 h after treatment. However, distinctive mRNA expression profiles for the PDGF ligand and receptor genes are exhibited by the uterus and vagina in response to DES, especially in that the induction of transcripts for PDGF-A and both receptor subunits is more transient in the vagina than in the uterus. Steroid specificity studies demonstrate predominant estrogen-specific regulation of mRNA induction for these genes. Analysis of cell-specific RNA expression by in situ hybridization reveals prominent induction of transcripts for the PDGF chains and receptor subunits in the uterine and vaginal epithelium after estrogen treatment, although enhanced expression of mRNA is also noted in the stroma, particularly for the PDGF receptor subunit genes. Cellular localization of the PDGF ligand and receptor protein molecules by immunohistochemistry detected significant immunostaining for all of these proteins in both the uterus and vagina of control animals. After DES treatment, the uterus exhibits a significant decrease in the level of PDGF ligand and receptor proteins immunostained within 6 h, whereas less dramatic effects ar observed in the vagina.(ABSTRACT TRUNCATED AT 400 WORDS)
The expansion of human infrastructure has contributed to novel risks and disturbance regimes in m... more The expansion of human infrastructure has contributed to novel risks and disturbance regimes in most ecosystems, leading to considerable uncertainty about how species will respond to altered landscapes. A recent assessment revealed that whooping cranes (Grus americana), an endangered migratory waterbird species, avoid wind-energy infrastructure during migration. However, uncertainties regarding collective impacts of other types of human infrastructure, such as power lines, variable drought conditions, and continued construction of wind energy infrastructure may compromise ongoing recovery efforts for whooping cranes. Droughts are increasing in frequency and severity throughout the whooping crane migration corridor, and the impacts of drought on stopover habitat use are largely unknown. Moreover, decision-based analyses are increasingly advocated to guide recovery planning for endangered species, yet applications remain rare. Using GPS locations from 57 whooping cranes from 2010 thro...
Electricity generation from renewable‐energy sources has increased dramatically worldwide in rece... more Electricity generation from renewable‐energy sources has increased dramatically worldwide in recent decades. Risks associated with wind‐energy infrastructure are not well understood for endangered Whooping Cranes (Grus americana) or other vulnerable Crane populations. From 2010 to 2016, we monitored 57 Whooping Cranes with remote‐telemetry devices in the United States Great Plains to determine potential changes in migration distribution (i.e., avoidance) caused by presence of wind‐energy infrastructure. During our study, the number of wind towers tripled in the Whooping Crane migration corridor and quadrupled in the corridor’s center. Median distance of Whooping Crane locations from nearest wind tower was 52.1 km, and 99% of locations were >4.3 km from wind towers. A habitat selection analysis revealed that Whooping Cranes used areas ≤5.0 km (95% confidence interval [CI] 4.8–5.4) from towers less than expected (i.e., zone of influence) and that Whooping Cranes were 20 times (95% ...
These data were developed to support an effort to understand how whooping cranes select stopover ... more These data were developed to support an effort to understand how whooping cranes select stopover habitat in the presence of wind-energy infrastructure. Location and associated data came from whooping cranes from the Aransas-Wood Buffalo Population, 2010-2016. We marked a sample of 57 whooping cranes with leg-mounted transmitters that acquired locations via the global positioning system (GPS) network and transmitted those data through the Argos satellite system. Cranes were captured either at their natal areas in and adjacent to Wood Buffalo National Park in Canada or at their winter terminus along the Texas Gulf Coast. Data herein include 9,347 ground locations used by whooping cranes during migration coupled with 19 potentially available locations for each used location (see processing steps for more information). Predictor variables hypothesized to explain variation in space use were included for all locations (used and available).
The whooping crane (Grus americana) is a bird species in North America currently protected under ... more The whooping crane (Grus americana) is a bird species in North America currently protected under federal endangered species legislation in the United States and Canada. The only self-sustaining and wild population of whooping cranes nests in and around Wood Buffalo National Park near the provincial border of Northwest Territories and Alberta, Canada. Cranes from this population migrate through the Great Plains of North America and winter along the Gulf Coast of Texas at Aransas National Wildlife Refuge and surrounding lands. These data support efforts to delineate a migration corridor for this population that can be used for conservation planning activities, including targeting conservation, mitigation, and recovery actions and assessing threats.
The whooping crane (Grus americana) is a listed endangered species in North America, protected un... more The whooping crane (Grus americana) is a listed endangered species in North America, protected under federal legislation in the United States and Canada. The only self-sustaining and wild population of Whooping Cranes nests at and near Wood Buffalo National Park near the provincial border of Northwest Territories and Alberta, Canada. Birds from this population migrate through the Great Plains of North America and winter along the Gulf Coast of Texas at Aransas National Wildlife Refuge and surrounding lands. These data represent migration corridors and precision estimates for this population that can be used for conservation planning activities, including targeting conservation, mitigation, and recovery actions and assessing threats.
Migratory birds use numerous strategies to successfully complete twice-annual movements between b... more Migratory birds use numerous strategies to successfully complete twice-annual movements between breeding and wintering sites. Context for conservation and management can be provided by characterizing these strategies. Variations in strategy among and within individuals support population persistence in response to changes in land use and climate. We used location data from 58 marked Whooping Cranes (Grus americana) from 2010 to 2016 to characterize migration strategies in the U.S. Great Plains and Canadian Prairies and southern boreal region, and to explore sources of heterogeneity in their migration strategy, including space use, timing, and performance. Whooping Cranes completed ~3,900-km migrations that averaged 29 days during spring and 45 days during autumn, while making 11–12 nighttime stops. At the scale of our analysis, individual Whooping Cranes showed little consistency in stopover sites used among migration seasons (i.e. low site fidelity). In contrast, individuals expres...
The effects of estrogen on the reproductive tract involve cell proliferation, migration, and diff... more The effects of estrogen on the reproductive tract involve cell proliferation, migration, and differentiation, which need to be well coordinated. Polypeptide growth factors are believed to play a vital role in a number of these cellular processes. Among the growth factors now documented to be associated with estrogen action are epidermal growth factor, transforming growth factor-alpha (TGF alpha), transforming growth factor-beta 1 (TGF beta 1), TGF beta 2, TGF beta 3, and insulin-like growth factor-I (IGF-I). Platelet-derived growth factors (PDGFs) are also potent mitogens, which consist of two peptide chains, denoted A and B, that dimerize to isoforms (PDGF-AA, -AB, and -BB) which differ in their functional properties, secretory behavior, receptor binding, and physiological effects. To study the role of the PDGF-A and -B chains and the PDGF receptor subunits, alpha and beta, during estrogen action in the mouse reproductive tract, time-dependent changes in the expression of these genes were examined by Northern and in situ RNA analyses and by immunohistochemistry after a single treatment of immature CD-1 (17- to 19-day-old) mice with the synthetic estrogen, diethylstilbestrol (DES). Our results demonstrate estrogen modulation of the expression of messenger RNA (mRNA) and protein for the PDGF ligands and receptors in both the uterus and vagina of the mouse. Northern and in situ RNA analyses demonstrate time-dependent estrogen induction of the mRNA levels for these genes in both tissues within 3 h after treatment. However, distinctive mRNA expression profiles for the PDGF ligand and receptor genes are exhibited by the uterus and vagina in response to DES, especially in that the induction of transcripts for PDGF-A and both receptor subunits is more transient in the vagina than in the uterus. Steroid specificity studies demonstrate predominant estrogen-specific regulation of mRNA induction for these genes. Analysis of cell-specific RNA expression by in situ hybridization reveals prominent induction of transcripts for the PDGF chains and receptor subunits in the uterine and vaginal epithelium after estrogen treatment, although enhanced expression of mRNA is also noted in the stroma, particularly for the PDGF receptor subunit genes. Cellular localization of the PDGF ligand and receptor protein molecules by immunohistochemistry detected significant immunostaining for all of these proteins in both the uterus and vagina of control animals. After DES treatment, the uterus exhibits a significant decrease in the level of PDGF ligand and receptor proteins immunostained within 6 h, whereas less dramatic effects ar observed in the vagina.(ABSTRACT TRUNCATED AT 400 WORDS)
The expansion of human infrastructure has contributed to novel risks and disturbance regimes in m... more The expansion of human infrastructure has contributed to novel risks and disturbance regimes in most ecosystems, leading to considerable uncertainty about how species will respond to altered landscapes. A recent assessment revealed that whooping cranes (Grus americana), an endangered migratory waterbird species, avoid wind-energy infrastructure during migration. However, uncertainties regarding collective impacts of other types of human infrastructure, such as power lines, variable drought conditions, and continued construction of wind energy infrastructure may compromise ongoing recovery efforts for whooping cranes. Droughts are increasing in frequency and severity throughout the whooping crane migration corridor, and the impacts of drought on stopover habitat use are largely unknown. Moreover, decision-based analyses are increasingly advocated to guide recovery planning for endangered species, yet applications remain rare. Using GPS locations from 57 whooping cranes from 2010 thro...
Electricity generation from renewable‐energy sources has increased dramatically worldwide in rece... more Electricity generation from renewable‐energy sources has increased dramatically worldwide in recent decades. Risks associated with wind‐energy infrastructure are not well understood for endangered Whooping Cranes (Grus americana) or other vulnerable Crane populations. From 2010 to 2016, we monitored 57 Whooping Cranes with remote‐telemetry devices in the United States Great Plains to determine potential changes in migration distribution (i.e., avoidance) caused by presence of wind‐energy infrastructure. During our study, the number of wind towers tripled in the Whooping Crane migration corridor and quadrupled in the corridor’s center. Median distance of Whooping Crane locations from nearest wind tower was 52.1 km, and 99% of locations were >4.3 km from wind towers. A habitat selection analysis revealed that Whooping Cranes used areas ≤5.0 km (95% confidence interval [CI] 4.8–5.4) from towers less than expected (i.e., zone of influence) and that Whooping Cranes were 20 times (95% ...
These data were developed to support an effort to understand how whooping cranes select stopover ... more These data were developed to support an effort to understand how whooping cranes select stopover habitat in the presence of wind-energy infrastructure. Location and associated data came from whooping cranes from the Aransas-Wood Buffalo Population, 2010-2016. We marked a sample of 57 whooping cranes with leg-mounted transmitters that acquired locations via the global positioning system (GPS) network and transmitted those data through the Argos satellite system. Cranes were captured either at their natal areas in and adjacent to Wood Buffalo National Park in Canada or at their winter terminus along the Texas Gulf Coast. Data herein include 9,347 ground locations used by whooping cranes during migration coupled with 19 potentially available locations for each used location (see processing steps for more information). Predictor variables hypothesized to explain variation in space use were included for all locations (used and available).
The whooping crane (Grus americana) is a bird species in North America currently protected under ... more The whooping crane (Grus americana) is a bird species in North America currently protected under federal endangered species legislation in the United States and Canada. The only self-sustaining and wild population of whooping cranes nests in and around Wood Buffalo National Park near the provincial border of Northwest Territories and Alberta, Canada. Cranes from this population migrate through the Great Plains of North America and winter along the Gulf Coast of Texas at Aransas National Wildlife Refuge and surrounding lands. These data support efforts to delineate a migration corridor for this population that can be used for conservation planning activities, including targeting conservation, mitigation, and recovery actions and assessing threats.
The whooping crane (Grus americana) is a listed endangered species in North America, protected un... more The whooping crane (Grus americana) is a listed endangered species in North America, protected under federal legislation in the United States and Canada. The only self-sustaining and wild population of Whooping Cranes nests at and near Wood Buffalo National Park near the provincial border of Northwest Territories and Alberta, Canada. Birds from this population migrate through the Great Plains of North America and winter along the Gulf Coast of Texas at Aransas National Wildlife Refuge and surrounding lands. These data represent migration corridors and precision estimates for this population that can be used for conservation planning activities, including targeting conservation, mitigation, and recovery actions and assessing threats.
Migratory birds use numerous strategies to successfully complete twice-annual movements between b... more Migratory birds use numerous strategies to successfully complete twice-annual movements between breeding and wintering sites. Context for conservation and management can be provided by characterizing these strategies. Variations in strategy among and within individuals support population persistence in response to changes in land use and climate. We used location data from 58 marked Whooping Cranes (Grus americana) from 2010 to 2016 to characterize migration strategies in the U.S. Great Plains and Canadian Prairies and southern boreal region, and to explore sources of heterogeneity in their migration strategy, including space use, timing, and performance. Whooping Cranes completed ~3,900-km migrations that averaged 29 days during spring and 45 days during autumn, while making 11–12 nighttime stops. At the scale of our analysis, individual Whooping Cranes showed little consistency in stopover sites used among migration seasons (i.e. low site fidelity). In contrast, individuals expres...
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