Details

Autor(en) / Beteiligte

• Hone, Jim

Titel

Estimating wildlife population trends: the case of the Helmeted Honeyeater

Ist Teil von

• Emu, 2014-01, Vol.114 (3), p.191-196

Ort / Verlag

CSIRO Publishing

Erscheinungsjahr

2014

Quelle

Taylor & Francis

Beschreibungen/Notizen

• Assessing trends in wildlife populations involves estimating whether those populations are stable, increasing or decreasing, and trends can infer the success or failure of management. This paper determines trends in a population of critically endangered Helmeted Honeyeaters (Lichenostomus melanops cassidix) in Victoria, Australia, using a range of estimation procedures. Analyses of breeding pairs data show the population of Helmeted Honeyeaters increased, with an annual finite growth rate (λ) of 1.07 (95% confidence intervals 1.02–1.12), over 8 years (1989–90 to 1996–97) then decreased over 12 years (1997–98 to 2008–09) with λ of 0.94 (95% CI 0.91–0.96). Demographic analysis estimated that during the first 8 years λ was 1.21 (95% CI 1.01–1.40), which overlapped the estimate of λ from breeding pairs data but was less precise. There were no demographic data for the later period of 12 years. The number of breeding pairs in 1 year was positively, although only weakly (R2=0.23), and significantly (P=0.03) related to annual rainfall 2 years prior. Wildlife management, such as that of Helmeted Honeyeaters, needs ongoing, quantitative assessment of trends involving measures such as λ, with associated 95% CI.