No abstract

Many highly invasive plant species have fleshy fruits which are eaten by native frugivorous animals. These frugivores play an important role in long-distance seed dispersal, and may also affect germination success. The aim of this study was to determine whether generalist frugivores enhance or decrease seed germination of invasive alien species through pulp removal or seed coat abrasion, besides serving as dispersal agents. Fruits of four fleshyfruited invasive alien plant species, namely Solanum mauritianum, Cinnamomum camphora, Lantana camara and Psidium guajava, were fed to three generalist avian frugivorous species, which have been observed feeding on these fruits in the wild. Seed retention time was recorded as this affects dispersal distance and the duration that seeds are exposed to the effects of the gut. Seeds removed from excreta, seeds from manually de-pulped fruit, and whole fruit were planted in soil trays housed in a greenhouse. Daily germination counts were done. Seed retention times differed significantly between bird species for all fruits, except those of C. camphora. However, all frugivores had a similar effect on the germination success of seeds of S. mauritianum, L. camara and P. guajava, showing that gut retention time was not important. Germination of seeds from manually de-pulped fruits did not differ from that of ingested seeds of all plant species, suggesting that seed coat abrasion was also not important. Pulp removal resulted in significantly higher germination rates, both in the two species with larger, multi-seeded fruit (S. mauritianum and P. guajava), and in the two species having single-seeded fruit with waxy exocarps (C. camphora and L. camara). Pulp removal also resulted in significantly earlier germination of L. camara and P. guajava seeds. Therefore, frugivores not only accelerate dispersal, but also greatly enhance seed germination of all fleshy-fruited invasive alien species in this study.

Wild parrots represent one of the greatest commercial interests in the legal trade in wild birds. Although it is difficult to quantify, there is a considerable illegal trade in wild parrots. Thirty-six per cent of the world's parrot species are listed by the International Union for the Conservation of Nature as threatened or near threatened, and 55% of these are threatened to some degree by trade. In this paper, we investigate the impact of protection on the number of nests that failed because of nestlings being taken by humans (hereafter nest take) and on nesting success in parrots. We collate data on parrot nest take from published and unpublished studies from Africa, Asia and Australasia, including countries and sites with and without national and local parrot protection measures in place. Nest take was insignificant in Australia, where all studies were from areas with both local and national protection. For less developed countries, levels of nest take were variable between studies, spanning the whole range from 0 to 100%. Protection significantly reduced nest take and correspondingly increased nesting success. Our results corroborate those for the Neotropics; thus, the advantages of protection appear to be independent of geographical location or political and economic conditions. We analysed data on legal trade in wild-caught parrots before and after implementation of the 1992 Wild Bird Conservation Act (which practically eliminated import of parrots to the USA) and found that there was no apparent shift in parrot imports to other global regions from the Neotropics. We suggest that conservation of parrots globally would benefit from similar legislation introduced in other regions, such as the EU (15), which is responsible for more than 60% of global imports of wild parrots.

No abstract

Despite the extent of subsistence farmland in Africa, little is known about endangered species that persist within them. The Cape Vulture (Gyps coprotheres) is regionally endangered in southern Africa and at least 20% of the population breeds in the subsistence farmland area previously known as the Transkei in the Eastern Cape province of South Africa. To understand their movement ecology, adult Cape Vultures (n = 9) were captured and fitted with global positioning system/global system for mobile transmitters. Minimum convex polygons (MCPs),and 99% and 50% kernel density estimates (KDEs) were calculated for the breeding and non breeding seasons of the Cape Vulture. Land use maps were constructed for each 99% KDE and vulture locations were overlaid. During the non-breeding season, ranges were slightly larger(mean [± SE] MCP = 16 887 km2 ± 366 km2) than the breeding season (MCP = 14 707 km2 ± 2155 km2). Breeding and non-breeding season MCPs overlapped by a total of 92%. Kernel density estimates showed seasonal variability. During the breeding season, Cape Vultures used subsistence farmland, natural woodland and protected areas more than expected. In the non-breeding season, vultures used natural woodland and subsistence farmland more than expected, and protected areas less than expected. In both seasons, human-altered landscapes were used less, except for subsistence farmland.Conservation implications: These results highlight the importance of subsistence farm land to the survival of the Cape Vulture. Efforts should be made to minimise potential threats to vultures in the core areas outlined, through outreach programmes and mitigation measures.The conservation buffer of 40 km around Cape Vulture breeding colonies should be increased to 50 km.