Willis and Millar (2005): Using marine reserves to estimate fishing mortality.

Willis, T.J. & R.B. Millar (2005) Using marine reserves to estimate fishing mortality. Ecology Letters 8: 47–52.

The pervasive effects of fishing mean that what is generally seen on our coasts is not ‘natural’. Here we demonstrate how no-take marine reserves, where all forms of human-induced disturbance are forbidden, can be used to estimate fishing mortality independently of the fishery. We suggest that reserves can be used to estimate other important population parameters in exploited marine species. Reserves can be used to combat the ‘shifting baseline’ syndrome and provide controls for determining what is natural in the oceans.

Efford and Cowan (2004): Long-term population trend of Trichosurus vulpecula in the Orongorongo Valley, New Zealand.

Efford, M. G.; Cowan, P. E. 2004. Long-term population trend of Trichosurus vulpecula in the Orongorongo Valley, New Zealand. In: R. L. Goldingay and S. M. Jackson (eds.) The biology of Australian possums and gliders. Surrey Beatty & Sons, Chipping Norton. Pp. 471–483.

Browsing by introduced brushtail possums has been predicted to shift the species composition of native forests away from palatable species, and thereby to reduce the density of possums those forests support. We tested this prediction with data from a population of possums monitored by capture–recapture over 35 years. Annual density varied within a relatively narrow band (6.5–13.7/ha) and the overall trend was slightly positive (+0.04 ± 0.025 /ha/year), despite the decline of some ‘preferred’ plant species. We speculate that possum carrying capacity was buffered against the loss of palatable plants because these were replaced by more resilient and fast-growing palatable species.