82 research outputs found

    Habitat Preferences and Censusing of Waterfowl Broods On Stock Ponds In South Central South Dakota

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    Waterfowl broods on stock ponds in south central South Dakota were surveyed in 1977 and 1978 to compare flush and observation techniques for censusing broods and to determine waterfowl brood habitat preferences. Results indicated that 72-8% of the broods present were censused by either technique alone. No differences were indicated between the 2 techniques when analyzed by species. For total brood counts, a significant (P\u3c0.05) difference was indicated for 1 of the 4 sample periods. Differences were found between the 2 techniques for certain age-classes of species and age-classes overall. Visibility correction factors were calculated for each species based on the percentage of known broods censused by each technique. Brood habitat preferences were examined using multiple regression and discriminant analyses of 33 pond and upland variables. Ponds were selected in a limited size range (0.71-2, 70 ha) to reduce variation in numbers of broods per pond due to pond size. However, variables indicative of pond size were significantly and positively associated to brood use of ponds in 8 of 9 analyses. Potential brood escape cover such as Polygonum spp. and Eleocharis spp. were positively associated with mallard (Anas platyrhynchos), (A. strepera), northern shoveler (A. clypeata) and class 1 broods. Large differences in numbers of broods on study ponds between the 2 years were likely due to increased nesting cover provided by yellow sweet clover (Melilotus officinalis). Study ponds with higher pH and more submersed aquatic vegetation had more brood use

    Understanding and Applying Ecological Principles in Cities

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    Renaturing cities requires a thorough understanding of how plants and animals interact with the urban environment and humans. But cities are a challenging environment for ecologists to work in, with high levels of heterogeneity and rapid rates of change. In addition, the hostile conditions often found in cities mean that each city, and region of a city, can have their own unique geographical context. In this chapter, we contrast urban ecological research in the UK and Brazil, to demonstrate the challenges and approaches needed to renature cities. In so doing, we provide a platform for global transferability of these locally contextualised approaches. The UK has a long history of urbanisation and, as a result of increasing extinction debts over 200 years, well-established urban ecological research. Research is generally focused on encouraging species back into the city. In contrast, Brazil is a biodiversity hotspot with relatively rich urban flora and fauna. This rich ecosystem is imperilled by current rapid urbanisation and lack of support for urban nature by city-dwellers. By working together and transferring expertise, UK and Brazilian researchers stand a better chance of understanding urban ecological processes and unlocking renaturing processes in each location. We present one such method for applying ecological knowledge to cities, so-called Ecological Engineering, in particular by discussing ecomimicry—the adaptive approach needed to apply global ecological principles to local urban challenges. By reading the ecological landscape in which urban developments sit and applying tailored green infrastructure solutions to new developments and greenspaces, cities may be able to reduce the rate at which extinction debt is accumulated

    Characteristics of successful puma kill sites of elk in the Black Hills, South Dakota

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    Elk Cervus canadensis nelsoni in the Black Hills, South Dakota, have been declining since 2006 and there is concern by resource managers and hunters that puma Puma concolor predation may be contributing to declining herds. We evaluated characteristics at sites where puma successfully killed elk in the Black Hills of South Dakota. We evaluated characteristics at coarse (79-ha plots) and fine (0.2-ha plot) scales across the landscape. Our primary objective was to obtain a better understanding of vegetation and terrain characteristics that may have facilitated greater susceptibility of elk to predation by puma. We evaluated effects of road density, terrain heterogeneity, probability of elk use, and vegetation variables at 62 puma kill sites of elk and 186 random sites to identify key landscape attributes where elk were killed by puma. Elk were killed by puma in high use areas. Elk were also killed in areas that had greater amounts of edge and intermediate ruggedness at the coarse scale. Further, elk were killed in areas with greater small tree density and woody debris at the fine scale. High germination rates of ponderosa pine trees are unique to the Black Hills and provide dense patches of cover for puma. We hypothesize that cover from small trees and woody debris provided conditions where puma could stalk elk in areas with optimal security cover for elk. We suggest managers implement vegetation management practices that reduce small tree density and woody debris in areas with greater density of meadow—forest edge if they are interested in potentially diminishing hiding cover for puma in elk high use areas

    Do Pine Trees in Aspen Stands Increase Bird Diversity

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    In the Black Hills of South Dakota, quaking aspen (Populus tremuloides) is being replaced by conifers through fire suppression and successional processes. Al- though the Black Hills National forest is removing conifers (primarily ponderosa pine [Pinus ponderosa])toincreasetheaspencommunitiesinsomemixedstands,ForestPlan guidelines allow four conifers per hectare to remain to increase diversity in the remaining aspen stand. We compared bird species richness in pure ponderosa pine, mixed stands dominated by ponderosa pine with quaking aspen, mixed stands dominated by aspen with ponderosa pine, and pure aspen stands. Stands dominated by ponderosa pine had lower (

    Multi-scale Habitat Use of Male Ruffed Grouse in the Black Hills National Forest

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    Ruffed grouse (Bonasa umbellus) are native upland game birds and a management indicator species (MIS) for aspen (Populus tremuloides) in the Black Hills National Forest (Black Hills). Our objective was to assess resource selection of male ruffed grouse to identify the most appropriate scale to manage for aspen and ruffed grouse in the Black Hills. During spring 2007 and 2008, we conducted drumming surveys throughout the central and northern Black Hills to locate used and unused sites from which we compared habitat characteristics at increasing spatial scales. Aspen with \u3e70% overstory canopy cover (OCC) was important to the occurrence of ruffed grouse across all spatial scales, but was most influential within 1600 m of drumming sites. Probability of a site being used was maximized when 20% of the 1600-m scale (~804 ha) had aspen with \u3e70% OCC. Ruffed grouse also selected for areas with many small, regular shaped patches of aspen over those with few large patches. At the smallest scale evaluated of 200 m (~12.5 ha), ruffed grouse selected drumming logs in close proximity to high stem densities of aspen with a minimal presence of roads. Ponderosa pine (Pinus ponderosa) had a negative influence on site selection at the 400-m (~50 ha), 1600-m (~804 ha), and 4800-m (~7200 ha) scales. Management for ruffed grouse in the Black Hills as the MIS for aspen should focus on increasing the extent of aspen with a goal of at least 20% occurrence on the landscape. Management efforts also should incorporate multiple age and size classes of aspen with an emphasis on enhancing early successional habitat to provide valuable cover through increased stem densities

    Seasonal Migration and Home Ranges of Female Elk in the Black Hills of South Dakota and Wyoming

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    Understanding the movement and dispersion patterns of elk (Cervus elaphus) on public lands and the underlying factors that affect each will facilitate elk management and help resolve conflicts between management that benefit elk and other uses of land resources. Consequently, there is a need to identify and examine the movement and dispersion patterns of elk in the Black Hills of South Dakota and Wyoming. Our study quantified seasonal movements, determined home ranges of female elk in two areas of the Black Hills, and examined underlying factors associated with each. Elk in the northern area did not demonstrate seasonal migration patterns. Rather, winter ranges in the northern area were contained mostly within the boundaries of the summer range. Elk in the southern area exhibited a north-south migration pattern that coincided with seasonal patterns of snowfall. These elk migrated to winter range in late November and returned to summer range in late April. Home ranges of elk in the southern area were larger (P \u3c 0.01) than home ranges in the northern area. Landscape characteristics with marginally-significant correlations to elk home range area included road density (P = 0.10), and forage:cover ratio (P = 0.08); density of primary and secondary roads and average slope were significantly correlated with elk home range area (P \u3c 0.01). Managers can use this information to develop strategies that meet population goals and reduce conflicts between management for elk and with other resources

    NOTES: WOODPECKER FORAGE AVAILABILITY IN HABI- TAT DISTURBANCES OF THE BLACK HILLS

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    Habitat disturbance events are critical to ecological systems in which some bird species have become specialized. The vegetation community, reduced competition, ability to avoid predators, nest-site characteristics, and forage opportunities within a disturbed ecosystem are all aspects that make it desirable for selection by particular species (Svärdson 1949, Cody 1981, Martin 1998). Specifically, avian species rely on the forest conditions created by fire, insects, and disease (Brawn et al. 2001, Hunter et al. 2001, Devictor et al. 2008). In the Black Hills National Forest (BHNF) of South Dakota,two major types of natural disturbances include wildfires and mountain pine beetle (Dendroctonus ponderosae; MPB) infestations. Dead trees (snags) created by these disturbances attract a suite of insects and wildlife species. Bark beetles (Family: Curculionidae, Scolytinae) and wood borer beetles (Families: Buprestidae and Cerambycidae) are of particular importance to black-backed woodpeckers (Picoides arcticus; BBWO) because they feed almost exclusively on the larvae of these insects (Beal 1911, Murphy and Lehnhausen 1998, Hutto 2006, Bonnot et al. 2008, Bonnot et al. 2009). Black-backed woodpeckers are of key interest to resource management agencies due to their habitat specialization needs and the management activities like wildfire salvage logging and pre-thinning that occur in these disturbance areas (Hutto 1995, 2006). These management activities potentially reduce nest site and food availability for BBWOs and, as a result, they were recently petitioned for protection under the Endangered Species Act (Hanson et al. 2012). Following a fire event or insect infestation, the relative probability of using trees affected by the disturbance increases over surrounding healthy trees (Rota 2013). As a result, we were interested in understanding the food that is available to the woodpeckers following these forest disturbances

    Nesting Ecology of Greater Sage-Grouse Centrocercus urophasianus at the Eastern Edge of their Historic Distribution

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    Greater sage-grouse Centrocercus urophasianus populations in North Dakota declined approximately 67% between 1965 and 2003, and the species is listed as a Priority Level 1 Species of Special Concern by the North Dakota Game and Fish Department. The habitat and ecology of the species at the eastern edge of its historical range is largely unknown. We investigated nest site selection by greater sage-grouse and nest survival in North Dakota during 2005 - 2006. Sage-grouse selected nest sites in sagebrush Artemisia spp. with more total vegetative cover, greater sagebrush density, and greater 1-m visual obstruction from the nest than at random sites. Height of grass and shrub (sagebrush) at nest sites were shorter than at random sites, because areas where sagebrush was common were sites in low seral condition or dense clay or clay-pan soils with low productivity. Constant survival estimates of incubated nests were 33% in 2005 and 30% in 2006. Variables that described the resource selection function for nests were not those that modeled nest survival. Nest survival was positively influenced by percentage of shrub (sagebrush) cover and grass height. Daily nest survival decreased substantially when percentage of shrub cover declined below about 9% and when grass heights were less than about 16 cm. Daily nest survival rates decreased with increased daily precipitation

    Robotics and Automated Systems for Environmental Sustainability: Monitoring Terrestrial Biodiversity

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    It is critical to protect Earth’s biodiversity, not just for its own intrinsic value, but also for the ecosystem services it underpins. Yet biodiversity is in crisis, with up to 1 million animal and plant species at risk of extinction, many within decades. This dire projection has captured world attention and triggered major mitigation efforts, but we are faced with problems in assessing global trends in biodiversity – which species, taxa, habitats and ecosystems are suffering the greatest declines? Are current mitigation measures having any positive impact? To answer key questions such as these, ecologists are seeking the help of robotics and automated systems (RAS) experts in the monumental task of attempting to monitor the state of biodiversity.In this White Paper, we have surveyed recent literature and consulted more than 120 international expert ecologists and engineers working in the fields of biodiversity and robotics. We have done this to evaluate the potential for developing robotic and autonomous systems that could massively extend the scope of terrestrial biodiversity monitoring across habitats globally. The complexities of biodiversity itself, and the many barriers and challenges that must be overcome in monitoring it, are formidable. We assess each of these barriers in turn, highlighting currently available RAS solutions, as well as nascent technologies that may be relevant to future RAS for biodiversity (RAS-BD) monitoring. Using this information, we have drawn up a roadmap of actions needed to address the barriers that should be easiest to overcome. Encouragingly, we find that a variety of existing RAS capabilities may be transferable to a biodiversity monitoring context. Beyond these are the harder barriers, where promising novel ideas being researched at UK universities and research institutes may, in time, become integral parts of future RAS-BD monitoring technology. We believe that RAS-BD technology has great potential to complement and considerably extend the field survey work undertaken by expert human observers. In the UK, we are fortunate in having particular strengths in both biodiversity and robotics research; as a nation we are in an ideal position to integrate them and become a leading force in the development and application of RAS-BD monitoring. To this end, we propose these recommendations that we hope will guide future government strategy in an area that is vital to the future of humanity:● The creation and funding of an integrated multidisciplinary task force, including academics and industry specialists with expertise in RAS and biodiversity, to support technological research and development.● Future UK funding and focus should be prioritised to utilise existing RAS capabilities to develop first generation RAS-BD technology for monitoring biodiversity.● Relevant nascent technologies being researched by numerous UK academic teams need increased and accelerated research and development funding to turn pioneering concepts into enhanced RAS-BD technology suited to overcoming the hardest monitoring barriers that ecologists encounter.● Education strategies should be developed to foster links between aspiring engineers, biologists andcomputer technologists, both in the curriculum of schools, and at later stages in universities and research facilities
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