Sharks and their relatives, the rays and chimaeras, are the diverse group of cartilaginous fishes that have evolved over 400 million years. Historically considered of low economic value to large-scale fisheries, today many of these fishes have become the target of directed commercial and recreational fisheries around the world, and they are increasingly taken in the by-catch of fisheries targeting other species.
These proceedings provide an overview of the ongoing research and management activities on polar bears in the circumpolar arctic. Together with the previous 12 proceedings, they provide an historic record of international efforts in protecting polar bears from over-harvest and document more recent concerns of threats arising from increased human activities in both the Arctic and in regions far beyond the realm of polar bears.
The fourth part in a series of action plan, this publication covers less than one-quarter of the world's antelope species that are found in North Africa, the Middle East and Asia. Herds numbering in the tens of thousands formerly occurred across the steppes and semi-deserts of Eurasia and India, but these have nearly all been reduced to fractions of their earlier size. Populations are fragmented across the region and several species have disappeared altogether during recent decades.
Bats make up a quarter of all mammals, and almost half of the species can be considered threatened or near threatened at a global level. This publication offers the results of the first comprehensive review to identify the conservation priorities for the 834 species of Microchiroptera.
These species, a group of about 150 ground-dwelling gamebird, are found on every continent apart from Antarctica. They live in a wide variety of habitats from tropical forests, high-altitude alpine zones, temperate forests, open country, to desert environment. Although widespread, little is known of the species occuring outside Europe and North America, but several species are considered at grave risk of extinction.
In the five years since publication of the 1995-99 action plan, the Megapode Specialist Group has been active in promoting, initiating and executing conservation and research projects on thermometer birds. But the conservation outlook for many species remains bleak. Their habit of nesting on or near beaches, often on small islands, make them vulnerable to disturbance and egg-collection, and several species are greatly threatened.
As large ground-dwelling birds, pheasants are widely hunted for food, plumage and the live bird trade - consequently many species are threatened. They are largely dependent on forested habitats, making them highly vulnerable to deforestation and habitat degradation. The first edition covered 1995-1999, and many of its recommendations have been addressed.
Bryophytes are of great importance in their ecosystems and for human well-being. They stabilise soil crust through colonisation of bare grounds and rocks; they are essential in nutrient recycling, biomass production, and carbon fixing; they control water through an effective retention mechanism; and they have economic value as peat for fuel, horticulture, oil absorption, and as sources of a wide variety of chemical compounds.
