Canadian Journal of Fisheries and Aquatic Sciences. Interaction network of subantarctic Macquarie Island. Interactions between invasive predators and other ecological disturbances. Our method provides an additional advantage by constraining the allowable parameter values to those which are consistent with both system stability and the validation data. 0000038904 00000 n If you do not receive an email within 10 minutes, your email address may not be registered, Deep Sea Research Part II: Topical Studies in Oceanography.

0000062287 00000 n

6. 36 0 obj <> endobj xref 36 72 0000000016 00000 n 0000143489 00000 n On Australia’s world heritage sub-Antarctic Macquarie Island only three species of invasive weeds are well established (Poa annua L., Stellaria media (L.) Vill. The results of other simulated eradication scenarios (i.e. 2008; but see also McInnes & Way 2010), and that the model does not take into account at‐sea factors that might be affecting giant petrel populations. In particular, short‐term responses are likely to be dominated by direct effects (i.e. rodents on islands, Howald et al. With an interest in off-target herbicide impacts, our work also includes a study of the movement and fate of herbicides in the cold climate Macquarie Island soils. “It shows that active animal management, such as removing invasive species, can have a positive effect on vulnerable populations. Indeed, in other island eradications, failure to eradicate mice has been more common than failure to eradicate rats (Howald et al. 0000595442 00000 n 0000143592 00000 n Jones & Ryan 2009). In some cases, these recoveries may have been driven by short‐term transient effects: the breeding success of grey petrels peaked in 2005 but then declined again in all sites except the northern tip, again thought to be due primarily to decreases in tall tussock vegetation and associated ground instability and erosion (Way & McInnes 2010). 0000071080 00000 n Macquarie Island is the result of the same geologic processes as the Himalaya mountain range. These weed species are believed to have initially been introduced through human activity, a threat which is likely to increase, although strict biosecurity is in place. Fortunately, Dr Cleeland had access to 20 years of albatross capture-mark-recapture data (collected by the Tasmanian Department of Primary Industries, Parks, Water and Environment –DPIPWE –between 1995 and 2014), as rabbit populations increased after the eradication of cats and the effectiveness of the Myxoma virus declined. ������������iF � ` ScH� endstream endobj 37 0 obj <>>> endobj 38 0 obj <>/ExtGState<>/Font<>/ProcSet[/PDF/Text/ImageC/ImageI]/Properties<>/XObject<>>>/Rotate 0/TrimBox[0.0 0.0 595.276 841.89]/Type/Page>> endobj 39 0 obj [66 0 R] endobj 40 0 obj <>stream
We used only those models that passed the stability and validation criteria in the previous simulations, and also passed a further stability test (i.e. A guide to ecosystem models and their environmental applications. 0000015634 00000 n 0000002210 00000 n Rabbit burrowing also reduced soil stability and enhanced natural erosion, leading to further large-scale habitat degradation. 3 for clarity of presentation. Responses to the simulated suppression of rabbits, rats, and mice on Macquarie Island. Rabbits increased and tall tussock vegetation decreased in all cases by definition, because these were the validation criteria. Spatial heterogeneity of mesopredator release within an oceanic island system, Rabbits, landslips and vegetation change on the coastal slopes of subantarctic Macquarie Island, 1980–2007: implications for management, Subantarctic Macquarie Island: Environment and Biology, Predation, competition, and prey communities: a review of field experiments, The introduction of the European rabbit flea, The Flora, Vegetation and Soils of Macquarie Island, How the Macquarie Island Parakeet became extinct, Changes in Rabbit Numbers on Macquarie Island 1974–2008, Remains of the extinct banded rail at Macquarie Island, Grey Petrel Procellaria cinerea Monitoring Report, Macquarie Island Marine Park 2009, Baseline Population Monitoring of Key Seabird Species, Macquarie Island Marine Park: Report on the 2008/09 Season, Measuring the impact of parental foraging by starlings (, Putting the pieces together: testing the independence of interactions among organisms, The indeterminacy of ecological interactions as perceived through perturbation experiments. She also used monthly estimates of island-wide rabbit density from DPIPWE and Australian Antarctic Division research, and weather event records from the Bureau of Meteorology. 1:CAS:528:DC%2BD2sXhtleqs73J&md5=dbc8f1b08d9cd5738bf3168b709e031f. Black-browed albatross fared the worst of the three species, being additionally affected by extreme rainfall in the absence of protective vegetation.

Redpolls, for example, are known to feed on seed heads of Pleurophyllum hookeri and Leptinella plumosa (Warham 1969; Parks & Wildlife Service 2009a), but it is not known whether they will forage in recovering and increasingly dense tussock and herbfield. Yodzis 1988; Dambacher et al. Little, however, is known about the soil seed bank or population dynamics after rabbit eradication, nor the effect of herbicides and non-chemical control methods in cold conditions. Outcomes not listed here (e.g.
Cats and Myxoma were completely removed from the models. 0000028868 00000 n ), although isolated occurrences of other species have been found and removed. 3 represent interactions that are poorly understood, and the importances of such interactions (to either of the interacting elements, or to other elements in the system) are unknown.

Black-browed albatross fared the worst of the three species, being additionally affected by extreme rainfall in the absence of protective vegetation. Brothers & Bone (2008) suggested that if the eradication of all three species was not possible, the eradication of rabbits (but not rodents) would be adequate for the recovery and increased breeding success of the majority of burrow‐nesting petrels. Successful suppression of rabbits and rats, but not targeting mice, yielded broadly similar but much less definitive results compared with the successful suppression of all three species. The approach used here examines outcomes across a large suite of plausible model structures. 0000441451 00000 n Details of the interactions within the Macquarie Island ecosystem. Human impacts, energy availability and invasion across Southern Ocean Islands. 0000009455 00000 n 0000219871 00000 n If the signs of the predictions matched the signs of the known (validation) responses, then this realisation was considered plausible and added to the pool of accepted realisations.