I also mean't to add that sterilising the male is of little benefit. You could wipe out 90% of male kangaroos and the population would still boom because all the females would still happily reproduce. (I haven't asked them but I don't think they are monogamous) In the case of feral pigs it is necessary to remove 80% of the population each year just to keep numbers at the same level. Why are so obsessed with camels? They are an introduced pest animal destroying many areas. A clean shot and it's all over.
