The potential for conservation of Polynesian birds through habitat mapping and species translocation

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Selected abstracts

92Z/00059 The geography and politics of species endangerment in Australia J.B. Kirk-patrick, Australian Geographical Studies, 29(2), 1991, pp 246-254. Australia has the worst rate of recent plant and animal species extinction of any continent or country of its size, and a large number of surviving native ecosystems into cultural ecosystems has been most complete. However, a considerable number of species have become extinct, or are now threatened, because of the introduction of two organisms. The fox Vulpes vulpes has had a massive impact on the medium-sized mammal fauna and the cinnamon fungus threatens the extinction of many of Australia's most floriferons heathland species. Institutional responses to the threat of continued loss of our unusual species have been belated and unco-ordinated. Only Victoria and Western Australia have adequate legislative provision for endangered species, and there has been some dispute on the adequacy of implementation in Victoria. A nationally funded endangered species programme was only initiated in 1988. Most non-government conservation organizations use endangerment as an argument for preserving large natural areas, but have yet to place the prevention of extinction near the top of their agenda. -from Author 92Z/00060 The potential for conservation of Polynesian birds through habitat mapping and sg~cies translocation J. Franklin & D. W. Steadman, Conservation Biology, 5(4), 1991, pp 506-521. Many populations and species of Polynesian land birds, particularly pigeons, doves, parrots, kingfishers, and passerines, are likely to become extinct within the next few decades unless we intervene to save them. One strategy is to translocate species onto previously occupied islands, if the habitat is suitable and current human activities are compatible. The method evaluated a procedure for analyzing terrestrial habitats in a geographical information system using aerial photographs, satellite imagery, topographic maps, and thematic maps. In the relatively simple island ecosystems of Atiu and Mitiaro (southern Cook Islands), mapping land cover and evaluating habitat suitability of l a n d birds is straightforward; measures of the shape and spatial relationships of land coverpatches are of limited value. Even small disturbances can eliminate a significant proportion of preferred habitat for land birds. Whenever possible, translocation efforts should focus on islands uninhabited by humans. The potential for successful translocation in the Cook Islands is limited to a few species. In Tonga, where more species of birds have been extirpated and where there are more uninhabited islands, the potential to reestablish viable land bird populations is much greater. -from Authors 92Z/00061 Wildlife conservation problems in the Juan Fernandez Archipelago, Chile W. R. P. Bourne, M. de L. Brooke, G. S. Clark & T. Stone, Oryx, 26(1), 1992, pp 43-51. These islands are remarkable for the number and variety of endemic plants, some of which aree pollinated by an endemic hummingbird. They are also the main breeding station of a fur seal Arctocephalus philippi which once numbered millions but was later thought to be extinct, and several widespread seabirds. So far the only losses appear to be the endemic sandalwoods and widespread elephant seal, but the other wildlife is threatened by deforestation, erosion and competition or predation from introduced species. -from Authors

Restoration ecology

tion, aggregate stability) were tested to determine the effect of soil properties on restoration efforts. Topsoil significantly increased overall plant cover, but there were no differences between topsoil depths. Topsoil did not contribute nutritionally to plant growth, but improved the soil physical properties, thus enhancing water relations. Indigenous plant materials that were collected on site produced greater plant cover (23%) than the native materials (19%) purchased from a commercial supplier. These differences were significant when scarifying and topsoilingpractices were combined with seeding. Nonseeded, topsofled treatments produced significant plant community development (18% cover) resulting from natural invasion from local intact communities. Nontopsoiled, scarified treatments seeded to indigenous materials provided appreciable plant cover (23%) following 2 yr of growth. -from Authors 92Z/00063 Mowing experiments to restore a speciesrich sward on sand dunes in Jersey, Channel Islands, GB P. Anderson & M. G. Romeril, in: Coastal dunes. Proc. 3rd European dune congress, Galway, 1992, ed R.W.G. Carter & others, (Balkema), 1992, pp 219-234. An extensive dune plain is dominated by tall, thick Rosa pimpinellifolia and grass-dominated communities containhag a low diversity of species. Mowing experiments were established in 1983 to examine the effect of annual and biennial treatments. No clear differences between them were found, but diversity was significantly higher on mown compared with unmown plots. In 1984, a new trial was designed to investigate the effects of mowing once near to, or distant from, rabbit warrens. Rabbit Oryctolagus cuniculus activity was encouraged on the plots near to the warrens. Plant diversity, richness and the number of annual herbs increased for 2-3 yr following mowing then tended to decline again. -from Authors 92Z/00064 Propagating dune grasses by cultivation for dune conservation purposes M. S. Dieckhoff, in: Coastal dunes. Proc. 3rd European dune congress, Galway, 1992, ed R.W.G. Carter & others, (Balkema), 1992, pp 361-366. Experiments were carried out with sand couch Agropyron junceum, marram grass Ammophila arenaria, Baltic marram grass Ammocalamagrostis baltica, sand sedge Carex arenaria and grey hair-grass Corynephorus canescens. The superiority of Ammocalamagrostis baltica was established. By fertilizing with 2 × 5g N/m 2 it is possible to increase productivity of A.baltica so that within one vegetative period, more than six plants can be propagated from one. Another advantage of A.baltica is that it is grazed less by rabbits Oryctolagus cuniculus than Ammophila arenaria. -from Author 92Z/00065 Evaluation of plant species for land restoration in central Tunisia D.E. Johnson, M. M. Borman & M. N. Ben Ali, Journal of Arid Environments, 22(4), 1992, pp 305-322. Screening of 241 plant species, varieties and accessions for potential use in revegetation was accomplished in Tunisia. Plants were ranked on the basis of survivability, vigor and production. Native species and accessions generally outperformed introduced ones. Annual species were superior to perennials. The most promising annual grasses are

Lolium rigidum and Bromus mollis. Legumes that have produced well are Medicago truncatula, Hedysarum carnosum and Hedysarum spinosissimum. Perennial grasses have survived at only two sites and only three species appear to have potential: Oryzopsis miliacea (syn. Piptath-

erum miliaceum), Eragrostis curvula and Dactylis glomerata. Establishment and productivity of all plants were highly variable from year to year and by location. -from Authors

92Z/00062 Restoration methods for abandoned roads at lower elevations in G r a n d Teton National Park, Wyoming N. R. Cotts, E. F. Redente & R. Schiller, Arid Soil Research & Rehabilitation, 5(4), 1991, pp 235-249. Treatments included seedbed scarification, fertilizing, seeding, topsoiling, and mulching. Plant cover was estimated and soil physical attributes (bulk density, infiltra-

92Z/00066 The value of fertilizer, surface applied and injected sewage sludge to vegetation established on reclaimed colliery spoil suffering from regression N. Michael, A. D. Bradshaw & J. E. Hall, Soil Use & Management, 7(4), 1991, pp 233-239. At the first harvest, surface applications of sewage sludge to a grass/clover sward (which had been directly esta-