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12.7. WILDLIFE DISEASES


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

12.8. SPECIES EXTINCTION

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.


 

12.8.1. Natural extinctions12.8.2. Artificial Extinction