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From: Peter McRae
Date: 10/30/98
Time: 12:41:57 PM
Remote Name: 203.5.10.41
Bruce and grade 6B True deserts are ares that receive very little rainfall, usually less than 200 mm per year. Much of inland Australia receives less than 350mm of rain each year and whilst these areas don't formally classify as deserts they are certainly arid and all areas that receive less than this amount of rainfall are collectively referred to as the arid zone. There are quite a few species that have declined in numbers over the past 200 years in the arid zone and small to medium sized mammals have been quite dramatically affected with many becoming extinct. There are quite a few that have declined in numbers and range to an extent that they are now regarded as endangered. This basically means means if thyings don't improve they too could become extinct. Ways of improving things for these species are to firstly find out the reasons for the declines, it may be food shortages, habitat loss or alteration, increased predation rates from exotic species such as the feral cat, foxes etc, competition from introduced species such as the rabbit and feral goats,changing fire patterns, increased grazing pressure from cattle and/or sheep etc. Once we understand what it is that has caused the declines we can try and reverse the situation as best we can eg controlling cats, foxes, goats etc and hope that the species in question responds favourably by successfully breeding and building it's numbers up. A couple of examples of endangered species in the arid zone are - Mulgara and Kowari ( small rat szed carnivorous marsupials), the Dusky hopping mouse (a small native mouse with enlarged hopping hindlimbs) and of course the Greater bilby ( the lesser bilby is now regarded as extinct). The word 'animals'also includes fish, birds, reptiles(snakes and lizards), frogs , insects and spiders etc however I don't have enough time here to go into all of these but we should remember that all of these other groups exist and whilst a hairy spider may not be quite as cute as a bilby thay still equally need to be looked after as they all play important roles in maintaining habitats for each other.