Since about 1600, 486 animal species have been recorded extinct. This represents about 0.04 of all animal species so far described. In the same period, 600 plant species are known to have disappeared, about 0.25 of the total. These figures are much smaller than those of the Permian/Triassic and Cretaceous/Tertiary mass extinctions. One might therefore conclude that at present life on earth is at comparatively little risk of extinction. However, there is a growing body of data to show that the converse is true.Resource Type: Journal Papers
Our results show that any further infrastructure development will put the remaining European population of wild mountain reindeer at great risk, as further habitat fragmentation will make the remaining undisturbed patches too small for holding viable populations. We discuss the importance of controlling piecemeal development in infrastructure for conservation of wildlife and argue that minimizing infrastructure development is likely one of the largest challenges in wildlife conservation ahead.Resource Type: Journal Papers
The Great Apes, including the chimpanzee, gorilla and orangutan, are threatened with extinction. All species are rapidly declining in abundance, even within protected areas.The main factors responsible for this decline are loss and degradation of habitat, and hunting. Construction of roads in forest areas is particularly damaging, as such development facilitates hunting and other activities which lead to habitat destruction.
This report assesses the impact of infrastructural development on great ape populations, using the GLOBIO modelling approach. GLOBIO is a multivariable spatial model, which estimates the extent of land area with reduced abundance and diversity of living organisms, as a result of infrastructural development. The model can also be used to develop scenarios of possible future impacts, based on the current rates of infrastructural development.Resource Type: Reports
Araucaria araucana (Monkey Puzzle), a southern South American tree species of exceptional cultural and economic importance, is of conservation concern owing to extensive historical clearance and current human pressures. Random amplified polymorphic DNA (RAPD) markers were used to characterise genetic heterogeneity within and among 13 populations of this species from throughout its natural range.
Although populations are geographically divided into Chilean Coastal, Chilean Andes and Argentinean regions, this grouping explained only 1.77 of the total variation. Within Andean groups there was evidence of a trend of genetic distance with increasing latitude, and clustering of populations across the Andes, suggesting postglacial migration routes from multiple refugia. Implications of these results for the conservation and use of the genetic resource of this species are discussed.Resource Type: Journal Papers
Aquilaria spp. (Thymelaeaceae) are the principal source of Gaharu, a valuable resin, yet information about their reproductive ecology is almost entirely lacking. Individuals of six species (A. beccariana, A. crasna, A. filaria, A. hirta, A. malaccensis and A. microcarpa) in cultivation in Indonesia were investigated to assess reproductive phenology, pollination, seed production and germination. Seed production and seedling dispersion were also assessed in natural populations of A. beccariana, A. malaccensis and A. microcarpa in Kalimantan.
The results indicate that Aquilaria spp. have high reproductive potential, but suggest that seed dispersal might be limited in natural forests. The implications of these results for the management of Aquilaria spp. are discussed.Resource Type: Journal Papers
Nineteen different areas in south-west Saudi Arabia from which mountain gazelle Gazella gazella cora were reported between 1988 and 1992 were visited during a field survey conducted between August 1992 and February 1993. Evidence of the continued presence of gazelle was found at 11 of these locations. All populations were small: estimated population sizes ranged from 5 to 50. In the remaining eight areas it appeared that gazelle had become locally extinct since the last report. Thus gazelle populations appear to be becoming extinct at an alarming rate (eight out of 19, or 42, in five years). The major cause of extinctions and threat to existing populations is illegal hunting. Traditional conservation measures will take time to implement, and may be too late to save most gazelle populations. Instead, protection enforced by a system of auxiliary rangers, recruited from among the local population and working in cooperation with the forces of the local civilian administration, is recommended.Resource Type: Journal Papers
The Last Stand of the Orangutan was prepared by a Rapid Response Team at UNEP/GRID-Arendal and UNEP World Conservation Monitoring Centre as a broad collaborative effort, involving contributors from the Ministry of Environment and Ministry of Forestry, Indonesia, and partners of the Great Apes Survival Project (GRASP).Resource Type: Reports
Growing deterministic and stochastic threats to many wild populations of large vertebrates have focused attention on the conservation significance of captive breeding and subsequent reintroduction. However, work on both gorillas and black rhinos questions this shift in emphasis. In these species, field-based conservation can be effective if properly supported and, although this is not cheap, per capita costs may still be considerably lower than for ex situ propagation in captivity. Here we attempt to broaden the scope of this debate by contrasting the breeding success and costs of in situ and captive programmes for a range of threatened mammals.Resource Type: Journal Papers
Aquilaria malaccensis (Thymelaeaceae) is the principal source of gaharu, one of the most valuable tropical forest products in international trade. Despite its economic importance, the autecology of this species is virtually unknown. Seedling growth and survival of A. malaccensis was monitored over a 15-month period in natural forest in West Kalimantan. Mean height growth rate was 21.2 + 2.3 cm year1, and was positively related to light availability (i^= 0.79, p < 0.001), but unrelated to distance to the nearest mature tree or seedling density. By the end of the observation period, fewer than 20% of seedlings surveyed initially were still alive, trampling and cutting being one of the main causes of mortality. A nursery experiment examined the influence of soil (two treatments), light availability (four treatments) and seedling density (four treatments) on growth. Although a decrease in irradiance was associated with significantly (p < 0.01, t - test) lower values for height and stem diameter, seedlings were able to survive under the low light treatment. Lower height growth rates and leaf increment were observed with higher seedling densities on the more fertile soil; no such effects of density were observed on the relatively infertile soil. The implications of these results for the sustainable management of A. malaccensis are discussed.Resource Type: Journal Papers
The ability of coral reefs to survive in a globally-warming world may crucially depend on the levels of pollution to which they are exposed, new findings indicate.
Scientists studying reefs that were bleached in the late 1990s by high surface sea temperatures have found a link between recovery rates and the levels of contamination entering coastal waters from developments on the land.Resource Type: Reports
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