Commercial harvesting of Kangaroos in Australia
by Tony Pople and Gordon Grigg
Department of Zoology, The University of Queensland
for Environment Australia, August 1999
Chapters 10,11,12 and 13 and Appendix 1 provided by staff at Environment Australia
Figure 16 (a-d) Queensland
Surveys by fixed-wing aircraft (solid symbols) began in 1980 by CSIRO with an interval to 1984. ANPWS and CSIRO jointly undertook surveys annually for 1985-92. The survey area is approximately 450,000 square km and the sampling intensity approximately 0.8%. For eastern grey kangaroos, correction factors of Caughley et al. (1976) were increased by a factor of 2. Surveys of 9-10 monitor blocks (a survey area of 50-57,000 square km) by helicopters using line transect methods (open symbols) began in 1991.
Numbers of kangaroos in the harvest area outside the survey area were calculated as a fraction of the survey area estimates. This was adjusted by estimates of densities in this area from ground surveys and relative harvest rates.
The harvest quotas between 1975 and 1979 were all species pooled, but became species-specific in 1980. They therefore represent the trends in numbers rather than any estimate of overall population size from which a statewide harvest rate could be determined. The jump in the red kangaroo quota in 1992 from 450,000 to 600,000 represents the change in methodology for determining the statewide population size.
The population estimate for whiptail wallabies is from Southwell et al. (1995b).
16a Population trends, harvest and quota figures for red kangaroos
16b Population trends, harvest and quota figures for eastern grey kangaroos
16c Population trends, harvest and quota figures for common wallaroos
16d Population trends, harvest and quota figures for whiptail wallabies