Given that a small number of other breeding sites occur in Port Kembla, the total population size is estimated to exceed 400 adult frogs. This suggests that few frogs live longer than about 2 years as adults. The longest interval between captures was 14-16 months, for three of these frogs. Only 13 frogs were recaptured outside the season of initial capture. Based on this ratio the sites contained at least 85 adult females in 1999-2000. The ratio of male to female frogs was 2.5:1, suggesting either that the population is male-dominated or that females are more cryptic in their behaviour than males and use habitat differently. In contrast, one female bell frog moved 1.25 km between one of these and the third site over a 14 month-period. Although these sites were only 500 m apart, no tagged frogs were recorded to move between them. Population estimation based on the mark and recapture of frogs in 1999-00 suggested that the two larger breeding sites together contain >300 adult frogs. Over 200 adult frogs were tagged across three breeding sites between November 1998 and January 2000. We conducted a tagging study of a population of the endangered Green and Golden Bell Frog Litoria aurea at Port Kembla, on the New South Wales south coast. Estimates of population size are fundamental to the development of effective management of threatened species.
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