< Previous | Contents | Next >
Diseases | Casual organism | Animal susceptible |
Tuberculosis | Mycobacterium spp | Deer, cat, primates, elephant |
Anthrax | Bacillus anthraxis | Gaur, chetal, wild pig, barking deer |
Rabies | Rabies virus | Tiger, lion, bear, mongoose, squirrel |
Foot and mouth disease | FMD virus | Gaur, nilgai, chetal, sambar, yak, mithun |
Rinder pest | Microbilli virus | Deer, wild pig, wild buffalo |
Trypanosomia | Trypanosomia virus | Tiger, elephant, sambar, macaque |
Taxoplasmosis | Taxoplasma gondii | Rhesus macaque, civet cat |
♤ Extinction is caused through various processes:
♤ Deterministic processes that have a cause and effect. E.g. glaciations, human interference such as deforestation.
♤ Stochastic processes (chance and random events) that effect the survival and reproduction of individuals.
E.g. unexpected changes of weather patterns, decreased food supply, disease, increase of competitors, predators or parasites, etc. that may act independently or add to deterministic effects.
♤ The impact of these processes will of course depend on the size and degree of genetic diversity and resilience of populations.
♤ Traits that adversely affect or increase a species vulnerability to extinction due to habitat fragmentation have been identified. These are:
♤ rarity or low abundance
♤ poor dispersal ability
♤ ecological specialization
♤ unstable populations
♤ high trophic status - as animals occupying a higher trophic level (i.e. the position of a species in a food chain) usually have smaller populations than those at lower levels (e.g. carnivores are fewer in number than herbivores)
♤ low adult survival rates
♤ low intrinsic rate population increase
♤ Body size, fecundity, dietary specialization.