Demography and condition of bushtail possum
Necropsy data were collected from brushtail possum (Trichosurus vulpecula) populations in forest habitat at Waihaha, and in farm habitat at Hohotaka, both in the central North Island of New Zealand. A major control operation reduced the Hohotaka population by 89% in 1988, and low population numbers were maintained thereafter by smaller annual operations. Finite rates of increase, calculated from birth and mortality data, were approximately unity for all three populations. Possums at Waihaha were in better morphological and physiological condition, and had lower birth and mortality rates and an older age structure, than those at Hohotaka. The contribution of spring breeding to the population was higher at Waihaha and Hohotaka post-poisoning than at Hohotaka pre-poisoning. After poisoning at Hohotaka, a morphological index of survivors' condition increased, but a fat-related index declined. Birth and mortality rates increased, male and female age structures became younger, and adult sex ratios became increasingly male biased (due in part to male-biased birth ratios). The usefulness of these results for predicting the demographic response of possum populations to sustained control of this pest in other areas is discussed.... [Show full abstract]
Keywordspossum; Trichosurus vulpecula; possum behaviour; biocontrol; forest populations; farm populations; possum breeding; brushtail possum; Waihaha; Hohotaka
Access RightsDigital thesis can be viewed by current staff and students of Lincoln University only. Print copy available for reading in Lincoln University Library. May be available through inter-library loan.
Showing items related by title, author, creator and subject.
Henderson, R.; Griffiths, J. W.; Ross, James G. (2002-08)This study aimed to quantify the risk to free-ranging, native birds from four new types of bait, which will be used with micro-encapsulated zinc phosphide (Zn₃P₂) for the control of possum. Six poisons are currently ...
Ogilvie, Shaun C.; Paterson, Adrian M.; Ross, James G.; Thomas, M. D. (The New Zealand Plant Protection Society (Inc.), 2006)To manage brushtail possums (Trichosurus vulpecula) accurate estimates of abundance are essential. Direct counts are not feasible for large populations and index techniques are normally employed. A new index technique for ...
Janson, K. W. (Lincoln University, 1990)Bovine Tuberculosis (Mycobacterium bovis) is endemic in over 13% of New Zealand. Despite the concentrated efforts of government departments and regional pest boards over the last 20 years, the disease continues to spread ...