Showing papers in "Biological Conservation in 1997"

TL;DR: The authors examined the distribution and abundance of butterfly species across an urban gradient and concomitant changes in community structure by censusing the butterfly and skipper populations at 48 points within six sites near Palo Alto, California, USA (all former oak woodlands).

TL;DR: The near-optimality, speed and simplicity of heuristic algorithms suggests that they are acceptable alternatives for many reserve selection problems, especially when dealing with large data sets or complicated analyses.

TL;DR: In this article, a demographic study of the Crozet population indicates that the earlier decline was mainly the result of increased adult mortality and secondarily of low recruitment, and that decreased fishing effort and a concentration outside the central Indian Ocean by the Japanese fishery during recent years has probably resulted in the slow recovery of these albatross populations as a result of improved adult survival and recruitment.

TL;DR: Both heuristics and optimizing algorithms have important roles to play in conservation planning and the choice of method will depend on the size of data sets, the representation goal, the required time for analysis, and the importance of a guaranteed optimal solution.

TL;DR: Not all amphibian species were negatively affected by the presence of predatory fish: those having either large bodies or clutch size co-occurred with predatory fish more frequently than those with small bodies or clutching size.

TL;DR: In this paper, a total of 517 species (148 vascular plants, 131 mosses, 64 hepatics, 142 lichens and 32 wood-inhabiting fungi) from 10 small remnants of boreal old-growth swamp forests were reported.

TL;DR: In this paper, an analysis and comparison of endemic plants in southeast France (215 taxa representing 7.2% of the flora) and in Corsica (240 taxa, 11% of flora) exhibit similar ecological preferences and life strategies.

TL;DR: In this paper, a single environmental awareness briefing reduced the rate of divers' contact with reef substrates from 1·4 to 0·4 contacts per diver per 7 min observation period, while the proportion of contacts that were voluntary, and so mainly directed at non-living substrate, increased to 63·8%.

TL;DR: In this paper, the differences between the composition of butterfly communities in gaps created by illegal logging and in closed canopy habitat were studied in montane forest in the Tam Dao Mountains, northern Vietnam.

TL;DR: The authors investigated how the topography of coral reef dive sites influences the type and amount of damage done by SCUBA divers to living corals and found that divers break more corals per 10 min interval (1·8±0·77, mean ± 1 SE) at one of the Shoulder sites than at any of the other five locations.

TL;DR: As expected by the identified trade-offs, Yellowstone grizzlies seemed to prey selectively upon moose, probably because of their solitary habits and forested surroundings, but otherwise favored vulnerable smaller-bodied ungulates such as elk calves.

TL;DR: In this paper, the authors examined factors which could influence the breeding success of native parrots in savannah and woodland areas in which substantial populations of the introduced hollow-nesting sturnids, myna Acridotheres tristis and starling Sturnus vulgaris, are present.

TL;DR: The authors investigated the relative economic values of the otter Lutra lutra and the water vole Arvicola terrestris, two species that occupy similar habitats and face common threats of habitat change, habitat fragmentation and pollution.

TL;DR: In this article, the authors derived habitat maps from a digital land cover map of the ∼ 178,000 km 2 Chesapeake Bay Watershed by using a spatial filtering algorithm and found that the distribution and abundance of many plants and animals are influenced by the spatial arrangement of suitable habitats across landscapes.

TL;DR: The exclusive home ranges of adult snakes suggest that social interactions (avoidance of conspecifics) may limit population densities, and hence that removal of some neonates may not reduce future densities of adults, and that conservation reserves must incorporate large forest areas adjacent to sandstone outcrops.

TL;DR: In this paper, the effect of afforestation on the avifauna of the Mpumalanga Province in South Africa was assessed. And the authors found that afforestation has a negative impact on grassland bird diversity even when the percentage area under plantation is relatively small.

TL;DR: Assuming that biomass production is closely related to seed production, fertilizing conservation headlands will result in reduced viability of populations of rare weeds, and cessation of fertilizer inputs may be required.

TL;DR: In this article, a retrospective PVA was performed on the Lord Howe Island woodhen Tricholimnas sylvestris (1) to compare the predictions of five different PVA packages (INMAT, GAPPS, RAMAS/age, RAMas/metapop and VORTEX).

TL;DR: The basic demographic parameters of six Bonelli's eagle Hieraaetus fasciatus populations in Spain and France were calculated from field data obtained in the last 15 years, and conservation efforts must be primarily directed towards increasing adult and preadult survival.

TL;DR: Some climatic and land-use variables, as measured on the available maps, are good predictors of the presence of lesser kestrel colonies in southern Spain, but less good at predicting the probability of extinction of colonies or the number of breeding pairs.

TL;DR: It is concluded that a mosaic of habitat types ranging from mudflats to high marshes is essential to sustain the high populations of shorebirds that use Delaware Bay during spring migration.

TL;DR: The authors examined change in vegetation across the edges of remnants of temperate rainforest from the Yarrawa Brush, Robertson, New South Wales, Australia, and compared the effects of remnant size, level of disturbance and topographical position on four groups of plants, including core rainforest, early coloniser, weed and pasture species, across abrupt boundaries between rainforest and cleared agricultural land.

TL;DR: This study shows that persistence of broad-headed snakes in an area may depend crucially not only on suitable rocky habitat, but on adjacent forests, and forestry practices should be designed to ensure that suitable ‘habitat trees’ are retained in forested areas near rocky cliffs.

TL;DR: Community composition differed significantly between parasite infected and uninfected regions of the sward, the most notable differences being a decline in the proportion of grasses, and a concomitant increase in theportion of dicotyledons, in the presence of the parasite.

TL;DR: The shellfish harvest from c.

TL;DR: In this article, an experimental longline fishery for hake Merluccius spp. commenced in the shelf waters off South Africa, and participants were required to record any birds caught, and these data were supplemented by ship-based observers on several vessels.

TL;DR: In this paper, the authors examined patterns of species loss and decline in a forest bird community following deforestation near Lagoa Santa, Brazil, and found 20, 29 and 34 forest species, respectively.

TL;DR: A range of grazing management methods are reviewed and their effects on vegetation in a number of different lowland heath types (dry, humid and wet heath, and mire) distributed across southern England and the introduction of grazing or higher stocking rates generally increased plant species richness, and the cover of grasses, forbs, bryophytes and lichens and bare ground while reducing litter depth and thecover of dwarf shrubs and scrub species.