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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.

Levin I.I.,University of Missouri-St. Louis | Levin I.I.,WildCare Institute | Levin I.I.,University of Colorado at Boulder | Colborn R.E.,University of Missouri-St. Louis | And 5 more authors.
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. We characterized 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. © 2016 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.

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.

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.

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.

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