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Caven A.J.,Platte River Whooping Crane Maintenance Trust Inc. | King K.C.,Platte River Whooping Crane Maintenance Trust Inc. | Wiese J.D.,Platte River Whooping Crane Maintenance Trust Inc. | Brinley Buckley E.M.,University of Nebraska - Lincoln
Journal of Insect Conservation | Year: 2017

Speyeria idalia populations have declined as much as 95 percent over the last three decades. Here we critically evaluate prairie habitat components along the Platte River in central Nebraska that S. idalia populations require in an effort to better inform conservation efforts. We utilized S. idalia count data from biological monitoring transects where vegetation, soils, land management, and flooding frequency data were also collected to describe the habitat constituents associated with S. idalia presence. We utilize comparative statistics, Pearson’s correlation analysis, and random forest analysis to model S. idalia habitat on land owned and managed by a small conservation NGO. Our findings suggest that S. idalia occupies specific habitat niches with a preference for well-drained soils (Inavale series) dominated by facultative upland plants, most prominently Andropogon gerardii. S. idalia is positively associated with large connected tracts of relict prairie containing Viola sororia and very moderate management regimes that remove shrubby cover (negatively associated) and promote forb cover (positively associated), while providing ample recovery time on burned and grazed patches for litter development (positively associated). Random forest analysis describes the presence of V. sororia, percent forb cover, and habitat isolation as the top three habitat variables of importance in predicting the presence/absence of S. idalia. Our finding that habitat isolation is a major predictor of S. idalia absence suggests many populations may be both spatially and genetically isolated. S. idalia’s future demands the preservation of tallgrass prairie fragments under management regimes that promote healthy populations and habitat connectivity. © 2017 The Author(s)


Chaez-RamA-Rez F.,Platte River Whooping Crane Maintenance Trust Inc. | Rodri-Guez-Estrella R.,CSIC - Doñana Biological Station
Waterbirds | Year: 2011

Although Sandhill Cranes (Gras canadensis) are considered as threatened in Mexico, there are no details on either their present winter distribution or descriptions of wetlands where cranes have been recorded. The objective here was to update the location of their wintering areas in Mexico and characterize the wetlands where they roost in winter. The wetlands were surveyed by ground and air, covering the Chihuahuan Desert in the states of Chihuahua, Coahuila, Nuevo LeÃn, Durango, San Luis PotosÃ-, Zacatecas and Guanajuato. Sandhill Cranes were recorded in 31 wetlands, of which 13 were new locations and extended the present distribution 237 km south. Three possible hypotheses, acting either individually or in combination, are proposed to explain the new locations. The main threats to the wetlands are their proximity to urban centers, disturbances to roosting areas due to human activity and land-use change. Some wetlands where cranes have been recorded had not been considered as priorities for waterfowl but would have importance for cranes and other species during migration and winter. Further studies of crane migration and wintering are important for conservation and management of the wetlands.


Jahn A.E.,University of Florida | Jahn A.E.,University of Buenos Aires | Cueto V.R.,University of Buenos Aires | Fox J.W.,Natural Environment Research Council | And 10 more authors.
Auk | Year: 2013

Descriptions of intra- and interspecific variation in migratory patterns of closely related species are rare yet valuable because they can help assess how differences in ecology and life-history strategies drive the evolution of migration. We report data on timing and location of migration routes and wintering areas, and on migratory speed and phenology, of Eastern Kingbirds (Tyrannus tyrannus) from Nebraska and Oklahoma and of Western Kingbirds (T. verticalis) and Scissor-tailed Flycatchers (T. forficatus) from Oklahoma. Eastern Kingbirds primarily departed the breeding site in September, migrating to the Amazon Basin (Bolivia and Brazil), >6,400 km from their breeding site, then used a second wintering site in northwestern South America (Colombia, Ecuador, and Peru) before returning to the breeding site in April. Western Kingbirds left Oklahoma in late July, migrating >1,400 km to northwestern Mexico, then to central Mexico and finally to Central America before returning to Oklahoma in April. Scissor-tailed Flycatchers departed Oklahoma mainly in mid-October, migrating to Central America (El Salvador, Guatemala, Honduras, and Nicaragua), ∼2,600 km from the breeding site, remaining there until early April before returning to Oklahoma. Timing of migration appears to be tightly linked to molt. Early departure of Western Kingbirds from the breeding site appears to be timed so that they molt in the Sonoran Desert region during the monsoon, whereas Scissor-tailed Flycatchers remain at their breeding site to complete molt in late summer, when insect prey are abundant. Eastern Kingbirds delay molt until reaching South America where, possibly, abundant fruit supports molt. © 2013 by The American Ornithologists' Union. All rights reserved.


Levin I.I.,University of Missouri-St. Louis | Levin I.I.,WildCare Institute | Zwiers P.,University of Missouri-St. Louis | Zwiers P.,Francis Marion University | And 16 more authors.
Conservation Biology | Year: 2013

Haemosporidian parasites in the genus Plasmodium were recently detected through molecular screening in the Galapagos Penguin (Spheniscus mendiculus). We summarized results of an archipelago-wide screen of 3726 endemic birds representing 22 species for Plasmodium spp. through a combination of molecular and microscopy techniques. Three additional Plasmodium lineages were present in Galapagos. Lineage A-infected penguins, Yellow Warblers (Setophaga petechia aureola), and one Medium Ground Finch (Geospiza fortis) was detected at multiple sites in multiple years. The other 3 lineages were each detected at one site and at one time; apparently, they were transient infections of parasites not established on the archipelago. No gametocytes were found in blood smears of infected individuals; thus, endemic Galapagos birds may be dead-end hosts for these Plasmodium lineages. Determining when and how parasites and pathogens arrive in Galapagos is key to developing conservation strategies to prevent and mitigate the effects of introduced diseases. To assess the potential for Plasmodium parasites to arrive via migratory birds, we analyzed blood samples from 438 North American breeding Bobolinks (Dolichonyx oryzivorus), the only songbird that regularly migrates through Galapagos. Two of the ephemeral Plasmodium lineages (B and C) found in Galapagos birds matched parasite sequences from Bobolinks. Although this is not confirmation that Bobolinks are responsible for introducing these lineages, evidence points to higher potential arrival rates of avian pathogens than previously thought. © 2013 Society for Conservation Biology.


Geluso K.,University of Nebraska at Kearney | Harner M.J.,University of Nebraska at Kearney | Harner M.J.,Platte River Whooping Crane Maintenance Trust Inc. | Vivian L.A.,University of Nebraska at Kearney | Vivian L.A.,U.S. Fish and Wildlife Service
Annals of the Entomological Society of America | Year: 2011

Ironoquia plattensis Alexander & Whiles (Trichoptera: Limnephilidae) was discovered along the Platte River in central Nebraska in the late 1990s, and basic information about its life history is not well understood. Here, we describe previously undocumented life-history traits that demonstrate strategies used by I. plattensis for surviving in fluctuating wetland environments in a landscape formally shaped by flooding. In an off-channel aquatic habitat along the Platte River, we observed 1) larvae residing in a slough that did not dry completely, 2) larvae emigrating from aquatic to terrestrial habitats 1 mo earlier than reported previously, 3) larvae moving above ground during the summer aestivation period, 4) larvae residing underground in soil during summer aestivation, and 5) mass emergence and swarming of adults after daybreak in autumn. Underground larval aestivation represents a previously undocumented behavior for this species. It is unclear whether aestivating underground represents an unreported common behavior or an infrequent response to local disturbances. At our site, insects may have been responding to a prescribed burn in April and introduction of cattle in mid-May that yielded the site unsuitable for aboveground aestivation. Additional studies on the life history for I. plattensis are warranted to help manage, locate, and protect the few sites where it occurs. © 2011 Entomological Society of America.


Galvez Aguilera X.,Empresa Nacional Para la Proteccion de Flora y Fauna | Chavez-Ramirez F.,Platte River Whooping Crane Maintenance Trust Inc.
Wilson Journal of Ornithology | Year: 2010

We conducted the first country-wide survey between 1994 and 2002 to examine the distribution, abundance, and conservation status of Sandhill Crane (Grus canadensis nesiotes) populations throughout Cuba. Ground or air surveys or both were conducted at all identified potential areas and locations previously reported in the literature. We define the current distribution as 10 separate localities in six provinces and the estimated total number of cranes at 526 individuals for the country. Two populations reported in the literature were no longer present and two localities not previously reported were discovered. The actual number of cranes at two localities was not possible to evaluate due to their rarity. Only four areas (Isle of Youth, Matanzas, Ciego de Avila, and Sancti Spiritus) each support more than 70 cranes. The remaining locations each have less than 25 individuals. Sandhill Cranes appear to be declining and have almost disappeared in Pinar del Rio and Granma provinces, and in northern Matanzas Province. Identified threats to the remaining populations include habitat modification (woody plant encroachment, agricultural expansion, and fire suppression), predation due to wild hogs (Sus scrofa), dogs (Canis lupus familiaris), mongoose (Crossarchus spp.), and poaching. © 2010 by the Wilson Ornithological Society.


Anthony D.J.,University of Nebraska - Lincoln | Bennett W.P.,University of Nebraska - Lincoln | Vuran M.C.,University of Nebraska - Lincoln | Dwyer M.B.,University of Nebraska - Lincoln | And 2 more authors.
MSWiM'10 - Proceedings of the 13th ACM International Conference on Modeling, Analysis, and Simulation of Wireless and Mobile Systems | Year: 2010

Developing applications for wireless sensor networks (WSNs) can provide many challenges. Environmental conditions have a large impact on the behavior of an application, but it may not be feasible to replicate the conditions of the deployment environment while creating the application. Furthermore, long-term deployment of monitoring applications require extensive pre-deployment analysis of such applications since the sensors cannot be accessed after their deployment. Through a combination of simulation and software engineering practices, it is possible to rigorously test and validate the software for WSNs. In this paper, several methods for simulating distributed mobile WSNs and testing the software are provided. These methods are used in the development of a WSN that was deployed to track Whooping Cranes during their year long migration. © 2010 ACM.


PubMed | University of Missouri-St. Louis, Platte River Whooping Crane Maintenance Trust Inc., University of New England at Biddeford and Vermont Center for Ecostudies Box 420 Norwich Vermont 05055
Type: Journal Article | Journal: Ecology and evolution | Year: 2016

Oceanic archipelagos are vulnerable to natural introduction of parasites via migratory birds. Our aim was to characterize the geographic origins of two Plasmodium parasite lineages detected in the Galapagos Islands and in North American breeding bobolinks (Dolichonyx oryzivorus) that regularly stop in Galapagos during migration to their South American overwintering sites. We used samples from a grassland breeding bird assemblage in Nebraska, United States, and parasite DNA sequences from the Galapagos Islands, Ecuador, to compare to global data in a DNA sequence registry. Homologous DNA sequences from parasites detected in bobolinks and more sedentary birds (e.g., brown-headed cowbirds Molothrus ater, and other co-occurring bird species resident on the North American breeding grounds) were compared to those recovered in previous studies from global sites. One parasite lineage that matched between Galapagos birds and the migratory bobolink, Plasmodium lineage B, was the most common lineage detected in the global MalAvi database, matching 49 sequences from unique host/site combinations, 41 of which were of South American origin. We did not detect lineage B in brown-headed cowbirds. The other Galapagos-bobolink match, Plasmodium lineage C, was identical to two other sequences from birds sampled in California. We detected a close variant of lineage C in brown-headed cowbirds. Taken together, this pattern suggests that bobolinks became infected with lineage B on the South American end of their migratory range, and with lineage C on the North American breeding grounds. Overall, we detected more parasite lineages in bobolinks than in cowbirds. Galapagos Plasmodium had similar host breadth compared to the non-Galapagos haemosporidian lineages detected in bobolinks, brown-headed cowbirds, and other grassland species. This study highlights the utility of global haemosporidian data in the context of migratory bird-parasite connectivity. It is possible that migratory bobolinks bring parasites to the Galapagos and that these parasites originate from different biogeographic regions representing both their breeding and overwintering sites.


Renfrew R.B.,Vermont Center for Ecostudies | Kim D.,Platte River Whooping Crane Maintenance Trust Inc. | Perlut N.,University of New England at Biddeford | Smith J.,The Nature Conservancy | And 2 more authors.
Diversity and Distributions | Year: 2013

Aim: In the Northern Hemisphere, bird migration from the tropic to the temperate zone in spring is thought to proceed at a rate determined in large part by local phenology. In contrast, little is understood about where birds go or the factors that determine why they move or where they stop during the post-breeding period. Location: Study sites were in Oregon, Nebraska and Vermont, and location data we collected extend south to Argentina. Methods: We deployed light-level geolocators on individual Bobolinks from three populations across the breeding range and compare their southbound movement phenology to austral greening as indicated by the Normalized Difference Vegetation Index. Results: Bobolinks from all breeding populations synchronously arrived and remained for up to several weeks in two sequential, small non-breeding areas that were separated by thousands of kilometres, before staging for pre-alternate moult. Similar to the migration patterns of birds to northern breeding areas, movements into the Southern Hemisphere corresponded to increasing primary productivity. Main conclusions: Our findings suggest that the Bobolink's southbound migration is broadly constrained by resource availability, and its non-breeding distribution has been shaped by the seasonal phenology of grasslands in both time and space. This is the first documentation of individual birds from across a continental breeding range exhibiting phenological matching during their post-breeding southward migration. Known conservation threats overlap temporally and spatially with large concentrations of Bobolinks, and should be closely examined. We emphasize the need to consider how individuals move and interact with their environment throughout their annual cycle and over hemispheric scales. © 2013 John Wiley & Sons Ltd.


Harner M.J.,Platte River Whooping Crane Maintenance Trust Inc. | Geluso K.,University of Nebraska at Kearney
Freshwater Science | Year: 2012

The Platte River caddisfly (Ironoquia plattensis) is a semiterrestrial limnephilid that inhabits sloughs along the Platte River in central Nebraska (USA). The species was discovered in 1997, and little is known about what controls its limited distribution or threatens its existence. We investigated effects of grazing by cattle (Bos taurus) on caddisfly abundance in a grassland slough. In April 2010, we established exclosures to isolate cattle from areas with caddisflies. We measured aquatic larval densities in April 2010 and 2011. We estimated grazing intensity from the normalized difference vegetation index (NDVI) values extracted from aerial images made in autumn 2010. Grazing intensity varied among plots, but ungrazed plots had more vegetation (higher NDVI values) than grazed plots. In April 2011, larval densities were greater in ungrazed than in grazed plots. Larval densities and NDVI values were strongly positively correlated, a result suggesting that reduction in vegetative cover from grazing was associated with decreased densities of caddisflies. Increased vegetative cover may have provided structure needed for adult courtship and inputs of organic matter to support larval feeding. Repeated, season-long grazing may have long-term negative consequences for the Platte River caddisfly in grassland sloughs when vegetation does not recover and other effects of cattle persist year after year. Resting pastures from grazing to permit vegetation to rebound appears to allow cattle and Platte River caddisflies to coexist in sloughs along the Platte River. © 2012 The Society for Freshwater Science.

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