Havens K.,Chicago Botanic Garden |
Jolls C.L.,Chicago Botanic Garden |
Jolls C.L.,East Carolina University |
Jolls C.L.,University of Michigan |
And 4 more authors.
Biological Conservation | Year: 2012
Larinus planus Frabicius (Curculionidae), is a seed-eating weevil that was inadvertently introduced into the US and was subsequently distributed in the US and Canada for the control of noxious thistle species of rangelands. It has been detected recently in the federally threatened Pitcher's thistle (. Cirsium pitcheri). We assayed weevil damage in a natural population of Pitcher's thistle at Whitefish Dunes State Park, Door County, WI and quantified the impact on fecundity. We then estimated the impact of this introduced weevil and other emerging threats on two natural, uninvaded populations of Pitcher's thistle for which we have long-term demographic data for 16. yr (Wilderness State Park, Emmet County, MI) and 23. yr (Miller High Dunes, Indiana Dunes National Lakeshore, Porter County, IN). We used transition matrices to determine growth rates and project the potential effects of weevil damage, inbreeding, goldfinch predation, and vegetative succession on Pitcher's thistle population viability. Based on our models, weevil seed predation reduced population growth rate by 10-12%, but this reduction was enough to reduce time to extinction from 24. yr to 13. yr and 8. yr to 5. yr in the MI and IN population, respectively. This impact is particularly severe, given most populations of Pitcher's thistle throughout its range hover near or below replacement. This is the first report of unanticipated ecological impacts from a biocontrol agent on natural populations of . Cirsium pitcheri. © 2012 Elsevier Ltd.
Kapfer J.M.,Elon University |
Pekar C.W.,Natural Resources Consulting Inc. |
Reineke D.M.,University of Wisconsin-La Crosse |
Coggins J.R.,University of Wisconsin - Milwaukee |
Hay R.,Bureau of Endangered Resources
Journal of Zoology | Year: 2010
Effective wildlife conservation plans should consider both the habitat needs and spatial requirements of the species in question. Studies that focus on the correlation between the habitat preferences and movement patterns of wildlife, particularly snakes, are uncommon. We attempted to determine how habitat preferences or quality influenced movement patterns of snakes. To answer this question, we created a case model that incorporated habitat preference or avoidance information rigorously obtained for bullsnakes Pituophis catenifer sayi from 2003 to 2005 at a site in the upper Midwestern US and compared it with minimum convex polygon estimates of home-range size. We employed geographical information systems to model the amount of preferred (open bluff faces) and avoided (agricultural fields and closed canopy forests) habitats within each estimated home range and compared them via multiple linear regression. We also tested the influence of gender, length and weight on home-range size. Our results indicate that home-range size increased primarily as a function of the amount of avoided habitat. This supports the hypothesis that habitat quality has an impact on wildlife movement patterns, and the relationship between habitat needs and spatial requirements should be considered when conserving or managing species. © 2010 The Authors. Journal compilation © 2010 The Zoological Society of London.
Matteson S.W.,Bureau of Endangered Resources |
Mossman M.J.,United Road Services |
Shealer D.A.,Loras College
Waterbirds | Year: 2012
Point-count surveys of Black Terns (Chlidonias niger surinamensis) were conducted in Wisconsin from 1980 to 2011 to assess statewide population trends of this declining species. The survey program consisted of 19 roadside transects, each with 15 stops (N = 285 stops total), spread across 15 counties throughout the state. Surveys were conducted at the same sites each year during three periods (19801982, 19951997, 20092011) by observers who visited each site once during the breeding season (25 May to 24 June) and counted the number of Black Terns seen during a 5-min interval. Over the three survey periods, statistically significant changes in abundance occurred on 14 of the 19 transects, most of which either were linear or exponential declines; no significant increases were evident. Survey-wide, the population declined in abundance by nearly 70% over the past 30 years and site occupancy declined by a similar percentage. Complete extirpation was recorded on four transects. Nest counts in two intensive study areas were consistent with the declining trend indicated by the point-count surveys. Likely causes of the decline include continued loss and degradation of breeding habitat and low annual adult survival probability, the latter for which reasons currently are unknown. Protection of remaining breeding colonies and restoration of degraded wetlands are recommended conservation measures for this species in Wisconsin and elsewhere.
Sloss B.L.,University of Wisconsin - Stevens Point |
Schuurman G.W.,Bureau of Endangered Resources |
Paloski R.A.,Bureau of Endangered Resources |
Boyle O.D.,Bureau of Endangered Resources |
Kapfer J.M.,University of Wisconsin - Whitewater
Conservation Genetics Resources | Year: 2012
Butler's Gartersnakes (BGS; Thamnophis butleri) are confined to open and semi-open canopy wetlands and adjacent uplands, habitats under threat of development in Wisconsin. To address issues of species identity and putative hybridization with congeneric snakes, a suite of 18 microsatellite loci capable of cross-species amplification of Plains Gartersnakes (T. radix) and Common Gartersnakes (T. sirtalis) was developed. All loci were polymorphic in BGS with mean number of alleles per locus of 16.11 (range = 3-41) and mean observed heterozygosity of 0.659 (range = 0.311-0.978). Loci amplified efficiently in the congeneric species with high levels of intra- and inter-specific variation. These loci will aid ongoing efforts to effectively identify and manage BGS in Wisconsin. © 2011 Springer Science+Business Media B.V. (outside the USA).
Woodford J.E.,Bureau of Endangered Resources |
Macfarland D.M.,Bureau of Endangered Resources |
Worland M.,Bureau of Science Services
Wildlife Society Bulletin | Year: 2013
We translocated and released a total of 90 (55 F and 35 M) wild American martens (Martes americana) from Minnesota to northern Wisconsin, USA, during 2008-2010. Our objective was to evaluate the short-term results of this translocation project by comparing marten dispersal, time to residency, and survival by release method, sex, and age categories. On average, translocated martens took 18 days (range = 1-64 days) and traveled 4.6 km (range = 0.4-45.7 km) from release sites before establishing residency. Although survival probabilities for adults and males were 0.84 and 0.79 and juveniles and females were 0.66 and 0.71, respectively, they were not statistically different. Translocated adult and juvenile survival was similar to resident adult and juvenile survival reported in Wisconsin and elsewhere. Predation (primarily by other carnivores) was the main cause (85%) of observed mortality for translocated animals, but it did not appear to be a major limiting factor for adults or juveniles. Contrary to some studies, we found no significant difference between release methods for any analyzed parameter, but we observed increased injuries to slowreleased individuals.We concluded there was no benefit resulting from slow-release or an acclimation period for translocation of American martens and that long-termmonitoring of the population is needed to evaluate species recovery in Wisconsin. © 2013 The Wildlife Society.