Showing papers in "Biological Conservation in 1986"

TL;DR: The best way to estimate the minimum sizes of reserves may be a three-step process that identifies target or keystone species whose disappearance would significantly decrease the value or species diversity of the reserve, including the importance of predation and herbivory in the maintenance of species diversity.

TL;DR: In this paper, the authors examined relationships among area, habitat heterogeneity and bird assemblages for 21 forest fragments (3 to 7620 ha) in an agricultural landscape near Ottawa, Canada.

TL;DR: There was no correlation between sprainting and the frequency of use of an area by otters, casting doubt on the use of spraint surveys as a method to assess habitat utilisation by otter populations.

TL;DR: In this paper, a multidisciplinary boundary model was developed to describe the processes of exchange across the administrative edges of nature reserves, which incorporates known dynamics from various disciplines and describes the interactions of these forces across the boundary.

TL;DR: Transhumance evolved a complex and widespread network of livestock routes in Spain, which were governed by livestock organisations benefiting from special legislation from the 13th century, and helped shape a characteristic landscape which has maintained one of the Mediterranean's most complex and interesting ecosystems.

TL;DR: An evaluation of the current international trade in musk indicates that the Himalayan population could reach a critically low level if present hunting pressures continue unabated and measures to conserve the species are outlined within the framework of sustainable use of living resources for development.

TL;DR: Most of the differences between common andRare species in the Sheffield region may be interpreted in terms of the availability of suitable habitats within the region with common species occupying common, and rare species less common, habitats.

TL;DR: The life history and ecology of the massasauga Sistrurus catenatus, an endangered rattlesnake, was studied from 1979 to 1983 at the Squaw Creek National Wildlife Refuge, Missouri, USA as mentioned in this paper.

TL;DR: It is suggested that pesticide use on cereal crops may reduce butterfly numbers and that arable farmland is a habitat in need of further study for butterfly conservation.

TL;DR: In this paper, the applicability of five conservation indices suggested for birds was evaluated in two wetland habitats (bogs and wet meadows) in SW Sweden and the censused sites were first evaluated and ranked by the authors, then ranked according to each of the indices.

TL;DR: The freshwater pearl mussel Margaritifera margaratifera L. has been found to survive in only three rivers from which the mussel was formely recorded.

TL;DR: In this paper, it is suggested that the reestablishment of a vigorous grassy sward would be the most effective long-term conservation strategy since utilisation would be compatible with conservation.

TL;DR: The attempted eradication and clearance programme for the introduced brown seaweed Sargassum muticum (Yendo) Fensholt is detailed; the stages in the development of a working system are presented here.

TL;DR: Examination of sheep migration abilities, the distances required for migration, and sheep mating patterns to challenge the inbreeding hypothesis conclude that the sound application of more traditional wildlife management techniques will likely preclude short- and long-term genetic problems.

TL;DR: Differences in the ecological history of families are suggested to be strongly affected by ancestral ecological specialisations which probably coincided with (or may even have been one of the major causal factors in) the differentiation of families at a time long before man's impact on the planet became marked.

TL;DR: In this article, measurements of aquatic vegetation at four sites of river channelisation works in south-central England were described and analysed, and physical factors determine the nature and extent of downstream deposition of sediment arising during construction depending on the depth of sediment, individual plant species may respond either by varying their rooting levels or by becoming smothered.

TL;DR: The effects of the 1982-1983 El Nino on Humboldt penguin colonies in Peru have been described in this article, with an overall population decline of 65% and the surviving population in 1984 was estimated to be between 2100 and 3000 adults.

TL;DR: In the Sheffield region of the UK, the authors of as mentioned in this paper pointed out that the greater levels of fertility and disturbance associated with modern land use is resulting in the creation of a new flora with the replacement of communities of stress-tolerant species (sensu Grime, 1974) by those with competitive or ruderal strategies.

TL;DR: The Dutch chalk grasslands were formerly very rich in bryophyte and lichen species as mentioned in this paper, but these species have disappeared nearly completely from the Dutch grasslands, and many characteristic acrocarps (e.g., Tortella spp., Trichostomum spp, Aloina spl., Pleurochaete squarrosa, Abietinella abietina, Camptothecium lutescens ) have decreased drastically.

TL;DR: Smaller patches, when compared to larger patches of the same biotope, are found to have a higher proportion of abundant generalists that are often the smaller species, and this seems to apply at least to forests, lakes and estuaries.

TL;DR: No clear-cut relationship exists between the occurrence of rare atlantic bryophytes and disturbance histories, and the persistence of desiccation-sensitive species depends on the quality of available habitats, as well as the nature of woodland disturbances.

TL;DR: Computer simulations were used to compare rates of genetic drift and allele fixation in intact populations with those in subdivided populations with the same total numbers of individuals, finding archipelagos of refuges with occasional inter-refuge migration appear to be the optimal design strategy for genetic conservation.

TL;DR: In this paper, the effects of human trampling on non-woody vegetation, leaf litter, trail width, and herbaceous species diversity were studied in an evergreen woodland environment.

TL;DR: The Essex coastline has a total of about 5000 ha of saltmarsh, of which Dengie Peninsula is the largest single marsh forming a part of a Grade 1 SSSI of international importance as mentioned in this paper.

TL;DR: In this article, the authors assess the loss of open heathland habitat at four sites in the Brecklands of East Anglia, and discuss successional change in relation to site management.

TL;DR: A comparison of exports of the same furbearer types (vizcachas, guanacos, skunks, wild cats, foxes, and coypus) between Chile and neighbouring Argentina suggests that in the latter country the conservation status of those furbearers is in danger as mentioned in this paper.

TL;DR: In this article, the authors investigated colony site selection and abandonment by least terns at 26 sites in New Jersey and found that the presence of shells or pebbles in a sandy substrate, and short, sparse vegetation, were the habitat characteristics of New Jersey least tern colony sites most strongly correlated with colony selection.

TL;DR: The impact of residential and agricultural development as the cause of water pollution on aquatic macrophyte communities in the New Jersey Pine Barrens was examined by comparison with unpolluted communities.

TL;DR: Cape vultures feed exclusively on sheep carcasses, within a limited foraging area as mentioned in this paper The size and shape of the foraging range was determined by means of a postal survey and confirmed by a radio-tracking study.

TL;DR: The prediction that wading bird reproduction can be sensitive to habitat quality and that these species should be useful as biological indicators for monitoring habitat quality is supported.