355 hyperendemic species live on islands, 196 on mainland including mainland
of Australia.
Many hyperendemics are assumed to be remnant populations of species with a
much wider range in the past. Some are identified as neo-hyperendemics that
evolved during the late Pleistocene or early Holocene, and simply have not been
able to enlarge their range, yet.
Because of the limited range of occurrence or population size the survival of
hyperendemics and local endemics should have highest priority. Therefore, any risk
including the probability of introduction of alien species, pathogens and biological
tourism should be minimized. On the other hand, measures to enlarge the
populations and safekeeping of genetic material should systematically be planned,
organized and intensified, for example with support from botanical gardens, seed
banks, zoos and aquariums.
General needs and consequences for different habitat types can only be specified very broadly. Thus, the consequences delineated here may serve as a basis for
discussion and should be assessed in every case at local to regional scales.
Forest, shrubland and freshwater habitats harbour most critically endangered
species on Earth. However, the importance and endangerment of habitats and
associated species differ considerably from region to region. For example, in Europe
and Central Asia habitat types of open and semi-open landscapes harbour much
more endemic and threatened species than forests.
Globally, agriculture, land use change, forestry, and biological resource use are
the most threatening factors for biodiversity. Many terrestrial ecosystems are directly
and indirectly affected e.g. by conversion, tilling, plantations, construction of roads
and buildings, and intensification of use, including increasing effects of physical,
chemical and biological processes.
In general, the risk of invasive species from abroad for the survival of native
species is higher where alien species represent niches which have not been occupied before, and is increasing with the introduction of hitherto not represented
functional roles (e.g. predators). Thus, many bird species on islands became extirpated by introduced animals such as rat, cat, goat, snake or others simply because the
native and often ground-breeding birds have had no experience with such aggressive
predators in their evolutionary life before. In all these cases competition was not the
problem but the representation of a new node in the food web. Therefore, the
situation on islands has to be assessed and evaluated in a different way compared
to most mainland regions. Across Europe, for example, no native species became
extinct because of the introduction of an alien species.
For hyperendemics invasive and other problematic species, genes and diseases
are the most important threat category.
Climate change and severe weather might especially be relevant in combination
with other threats.
In general, threats and the composition of endangered species differ with respect
to habitat type. Thus, also consequences and recommendations have to be specified
with respect to locality, habitat type and target species.
234
C. Hobohm et al.
of Australia.
Many hyperendemics are assumed to be remnant populations of species with a
much wider range in the past. Some are identified as neo-hyperendemics that
evolved during the late Pleistocene or early Holocene, and simply have not been
able to enlarge their range, yet.
Because of the limited range of occurrence or population size the survival of
hyperendemics and local endemics should have highest priority. Therefore, any risk
including the probability of introduction of alien species, pathogens and biological
tourism should be minimized. On the other hand, measures to enlarge the
populations and safekeeping of genetic material should systematically be planned,
organized and intensified, for example with support from botanical gardens, seed
banks, zoos and aquariums.
General needs and consequences for different habitat types can only be specified very broadly. Thus, the consequences delineated here may serve as a basis for
discussion and should be assessed in every case at local to regional scales.
Forest, shrubland and freshwater habitats harbour most critically endangered
species on Earth. However, the importance and endangerment of habitats and
associated species differ considerably from region to region. For example, in Europe
and Central Asia habitat types of open and semi-open landscapes harbour much
more endemic and threatened species than forests.
Globally, agriculture, land use change, forestry, and biological resource use are
the most threatening factors for biodiversity. Many terrestrial ecosystems are directly
and indirectly affected e.g. by conversion, tilling, plantations, construction of roads
and buildings, and intensification of use, including increasing effects of physical,
chemical and biological processes.
In general, the risk of invasive species from abroad for the survival of native
species is higher where alien species represent niches which have not been occupied before, and is increasing with the introduction of hitherto not represented
functional roles (e.g. predators). Thus, many bird species on islands became extirpated by introduced animals such as rat, cat, goat, snake or others simply because the
native and often ground-breeding birds have had no experience with such aggressive
predators in their evolutionary life before. In all these cases competition was not the
problem but the representation of a new node in the food web. Therefore, the
situation on islands has to be assessed and evaluated in a different way compared
to most mainland regions. Across Europe, for example, no native species became
extinct because of the introduction of an alien species.
For hyperendemics invasive and other problematic species, genes and diseases
are the most important threat category.
Climate change and severe weather might especially be relevant in combination
with other threats.
In general, threats and the composition of endangered species differ with respect
to habitat type. Thus, also consequences and recommendations have to be specified
with respect to locality, habitat type and target species.
234
C. Hobohm et al.