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Necedah, WI, United States

King R.S.,Necedah National Wildlife Refuge | Adler P.H.,Clemson University
Journal of Vector Ecology | Year: 2012

Hematophagous insects can negatively affect the reproductive success of their vertebrate hosts. To determine the influence of hematophagous insects on endangered vertebrates requires specially designed programs that minimize disturbance to the hosts and address problems associated with their small populations. We developed and evaluated a surveillance program for black flies potentially affecting a population of whooping cranes (Grus americana) introduced to central Wisconsin, U.S.A. In one of the few studies to survey host-seeking female black flies and their immature stages concurrently, we processed nearly 346,000 specimens and documented 26 species, of which only two, Simulium annulus and Simulium johannseni, were attracted to nesting whooping cranes. Attempts to assess black fly populations with artificial nests and real crane eggs were unsuccessful. Carbon-dioxide traps performed well in describing black fly taxa on the landscape. However, the number of black flies at whooping crane nests was consistently higher than the number captured in carbon-dioxide traps. The carbon-dioxide traps poorly described the presence/absence, population fluctuations, and periodicity of black flies at whooping crane nests. The weak performance of the carbon-dioxide traps might have resulted from microhabitat differences between trap locations and nests or from Simulium annulus and Simulium johannseni using sensory cues in addition to carbon dioxide to find hosts. Choice of trapping techniques, therefore, depends on the information required for the particular study objectives. © 2012 The Society for Vector Ecology.

King R.S.,Necedah National Wildlife Refuge | Trutwin J.J.,Necedah National Wildlife Refuge | Hunter T.S.,Necedah National Wildlife Refuge | Varner D.M.,Southern Illinois University Carbondale
Journal of Wildlife Management | Year: 2013

Understanding the influence of environmental stressors on daily nest survival of introduced birds is important because it can affect introduction success as well as the ability to evaluate introduction programs. For long-lived birds with low annual production, adjustment to local breeding conditions can take many years. We examined nest success rates of 2 introduced bird species, whooping crane (Grus americana) and trumpeter swan (Cygnus buccinator), in Wisconsin. Both species are long-lived with low annual reproductive rates. Trumpeter swans were established in our study area approximately 10 years before whooping cranes. We predicted that trumpeter swans would show less sensitivity to environmental stressors. We used daily nest survival rates (DNSRs) as our response variable to model several environmental parameters including weather, phenology, and ornithophilic black flies (Diptera: Simuliidae). Additionally, we examined the influence of captive history, age, release method, energetics, and nesting experience on whooping crane DNSRs. Daily nest survival of whooping cranes was the most sensitive to stressors. Trumpeter swan daily nest survival showed less sensitivity to the same stressors. Daily nest survival for both species peaked later in the nesting season, after 30 April and before 30 May. We also found that the daily nest survival rate (DNSR) for whooping cranes was potentially affected by captive exposure (measured by generations removed from the wild). Our results highlight the difficulties associated with conservation of long-lived birds with low annual productivity as they adjust to local breeding conditions and that nest phenology at the source location can determine how these conditions are interfaced. We recommend that the juxtaposition of source and introduction location nest phenology be considered prior to introduction site selection. Additionally, strategically selecting offspring from captive pairs with nest phenology similar to that of sympatric species at the introduction location should be considered. Published 2013. This article is a U.S. Government work and is in the public domain in the USA. Copyright © The Wildlife Society, 2013. This article is a U.S. Government work and is in the public domain in the USA.

King R.S.,Necedah National Wildlife Refuge | Boysen J.R.,Necedah National Wildlife Refuge | Brenneman J.M.,Necedah National Wildlife Refuge | Cong R.M.,University of Wisconsin - Madison | Hunter T.S.,Necedah National Wildlife Refuge
Ecosphere | Year: 2015

Hybridization or the breakdown of reproductive barriers has perplexed conservationists for centuries. Hybridization between the golden-winged warbler ( Vermivora chrysoptera) and blue-winged warbler ( Vermivora cyanoptera) has received extensive study across North America for more than a century and indicates widespread, bi-directional genetic introgression. We found evidence fire is creating habitat conditions leading to isolation between nesting golden-winged warblers and blue-winged warblers. This effect is likely the result of fire's ability to promote grass cover and suppress woody plants, leading to habitat use partitioning between golden-winged warblers and blue-winged warblers. In addition to minimizing contact between the species, fire is creating habitat conditions on mixed sites that greatly favors golden-winged warblers over blue-winged warblers. Fire provides a plausible explanation for the original split in these sister species and its near elimination from eastern North America provides at least a partial explanation for the golden-winged warbler's extensive range-wide decline. Fire also provides a potential conservation tool by isolating golden-winged warbler and blue-winged warbler nesting populations. If nesting populations can be isolated, relatively rapid phenotypic sorting can be achieved, which could lead to a clearer distinction between the taxa as well as species preservation. © 2015 King et al.

King R.S.,Necedah National Wildlife Refuge | Espenshade J.L.,Necedah National Wildlife Refuge | Kirkpatrick-Wahl S.K.,Necedah National Wildlife Refuge | Lapinski M.K.,Necedah National Wildlife Refuge | And 2 more authors.
Wildlife Biology | Year: 2013

Translocation of captive-reared animals is widely used as a tool for endangered species recovery. Frequently, translocated populations have relatively low initial productivity, requiring management intervention. A translocated population of whooping cranes Grus americana in central Wisconsin is such a case. We examined chick mortality for this population and used daily chick survival rates as our response variable to model several parameters including phenology, chick age, energetics and parent age and experience. We also developed and evaluated adoption techniques using sandhill cranes Grus canadensis to mitigate the effects of high chick mortality and increase the probability of fledging. Our results illustrate the challenges that translocated populations can face as they encounter novel breeding conditions. We found that whooping crane daily chick survival was relatively low and most mortality events occurred within the first 20 days. Our results indicated that variables related to age of the parents as well as the pair's previous chick rearing experience were useful for predicting daily chick survival. We found that sandhill crane foster parents readily accepted replacement chicks. We also demonstrated adopted chicks acceptance of foster parents and that the chicks' source (captive-born vs wild-born) did not affect success of the adoption. Chick adoption provides several management options that could be used to bypass the period when chicks experience the greatest mortality. Reducing chick mortality and developing techniques to increase the number of fledged chicks is paramount for whooping crane recovery as well as the recovery of other endangered bird species. © Wildlife Biology, NKV.

King R.S.,Necedah National Wildlife Refuge | Espenshade J.L.,Necedah National Wildlife Refuge | Kirkpatrick-Wahl S.,Necedah National Wildlife Refuge | Lapinski M.K.,Necedah National Wildlife Refuge | And 2 more authors.
Waterbirds | Year: 2013

Recovery of endangered birds often involves population establishment through introduction of captive-reared individuals. Growth of a captive-reared Whooping Crane (Grus americana) population introduced into central Wisconsin is currently limited by a high rate of nest desertion, which is thought to possibly be related to poor general nest attentiveness. Whooping Crane nest attentiveness and associated covariates were studied. Egg infertility and embryonic death rates were assessed as well as their effects on daily nest survival estimates. Techniques to minimize predation exposure of unattended eggs were developed and evaluated. Most Whooping Crane pairs deserted their eggs and all left them unattended. Nest desertion was associated with poor nest attentiveness. Variables related to age of the nesting pair were useful for modeling nest attentiveness. Daily nest survival estimates based solely on adult presence potentially produced inflated measures. Results suggest management interventions can minimize predation exposure of unattended eggs. Bypassing a portion of incubation has the additional advantage of simultaneously addressing nest failure and maximizing productivity.

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