When professional control diminishes, killing of kangaroos does not stop; amateur shooting increases.  Kangaroos in drought starve through over population. Regulators cannot monitor the number of kangaroos killed nor ensure high standards of dispatch of animals. 

Kangaroo industry is taking only a tiny percentage of the population, and populations fluctuate due to drought. 

These are the findings of study by George Wilson and Melanie Edwards in an article published by the Royal Zoological Society of NSW on the topic of professional amateur kangaroo