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Wellington, New Zealand

Steffens K.E.,Nelson Lakes Area Office | Sanders M.D.,Boffa Miskell Ltd | Gleeson D.M.,Landcare Research | Pullen K.M.,Urtica Inc. Ecological Monitoring and Consultancy | Stowe C.J.,Urtica Inc. Ecological Monitoring and Consultancy
New Zealand Journal of Ecology

Predators at black-fronted tern (Chlidonias albostriatus) nests on the Wairau braided riverbed in Marlborough, New Zealand, were identified using (1) mtDNA analysis of 438 swabs from shell remains, nest contents, and carcass remains, and (2) digital video surveillance of 85 nests. DNA analysis suggested harriers (Circus approximans) were the main predator of tern eggs (171 of 192 shell samples containing predator DNA). Cats (Felis catus) and stoats (Mustela erminea) were the probable predators of the majority of adult terns killed (9 and 8 respectively, of swabs from 19 carcasses). Video results were broadly, though not entirely, consistent with the DNA results, and showed that harriers were the main predator of eggs (9 of 19 videoed predation events), followed by Southern black-backed gulls (Larus dominicanus dominicanus; 3/19); hedgehogs (Erinaceus europaeus occidentalis; 2/19), ship rats (Rattus rattus; 2/19), pied oystercatchers (Haematopus finschi; 2/19) and stoats (1/19). DNA was analysed from nine of the 19 videoed nests but the only predator DNA obtained was from harriers (four nests). Sixty-four percent of depredated nests (683/1063) contained no eggshell remains at the next monitoring visit after predation. DNA analysis of nest material from 71 of these empty nests yielded only one predator result; video footage was therefore essential to identify the cause of 12 empty nests at 19 videoed nest predations. Terns removed the depredated egg remains from eight nests; blackbacked gulls consumed eggs at three nests; and a stoat carried the eggs away from one nest. Hedgehog DNA was not found on shell remains from nests with videoed hedgehog predations. Analysing DNA from eggshell and carcass remains is a valuable new tool in wildlife research and management because it can identify predator species and indicate their relative importance. However, our results show that predator species are not equally detectable using this technique, leading to biases in the DNA results. This 'detectability bias' needs to be further quantified, and recognised when interpreting DNA results. © New Zealand Ecological Society. Source

Baling M.,Massey University | Baling M.,University of Auckland | van Winkel D.,Massey University | van Winkel D.,Bioresearches Group Ltd | And 6 more authors.
New Zealand Journal of Ecology

Tiritiri Matangi Island is one of the oldest community-driven island restoration projects in New Zealand. While great effort has been directed towards recovery of vegetation and avian communities since the 1980s, restoration of the island's reptile fauna has not been initiated until early 2000s. Tiritiri Matangi supports only three remnant reptile species, which is considerably low given the island's size and geographic location. In recognition of this and the importance of reptiles in ecosystem function, translocations of several reptile species have been undertaken. The translocations presented opportunities for integrating in-depth scientific studies in regard to applied conservation management of native reptiles with experimental approaches. This review summarises research efforts on Tiritiri Matangi to date, including post-graduate studies that have contributed to: (1) baseline information on resident species (Oligosoma moco, O. aeneum, Woodworthia maculata, O. smithi & Naultinus elegans); (2) understanding the importance of seabird co-habitation for Sphenodon punctatus; (3) post-release behaviours (dispersal and habitat selection) of Hoplodactylus duvaucelii; (4) body colour adaptation of O. smithi following translocation; (5) quantifying avian predation on lizard populations; and (6) measuring the short-term success of all translocations. Numerous research opportunities remain, either on existing populations or future translocations to the island. Emphasis has been placed on the involvement of public and local community volunteers in all reptile research. These groups are key stakeholders in the restoration of Tiritiri Matangi. Measurement of translocation success for New Zealand reptiles is dependent on long-term monitoring (> 10 years) and research, since these endemic reptiles exhibit distinctive characteristics such as slow maturity, low reproductive rates, and very high longevity. The process of restoration of a fully functioning New Zealand ecosystem is similarly slow, therefore, long-term study or monitoring will also enable assessment of the island's restoration outcome over time. © New Zealand Ecological Society. Source

Bentley J.A.,Boffa Miskell Ltd
Australian Coasts and Ports 2015 Conference

Aquaculture, notably farming of mussels, salmon and oysters, has grown from small beginnings to become a significant primary industry in New Zealand. Economic activity, coupled with increasing environmental protection, means that the consenting of new, or the expansion of existing aquaculture developments is not always a straightforward process. A recent Supreme Court decision has further amplified the importance of the hierarchy of planning documents to decision makers, as well as the relationship between the precautionary principle and adaptive management of adverse effects. Landscape and natural character effects are often cited as one of the pertinent issues in deciding whether aquaculture development is appropriate in a particular location. Councils are under pressure to ensure that their regional and district plans are robust enough to confirm that appropriate decisions can be made in the coastal environment. The Supreme Court in Environmental Defence Society Inc v New Zealand King Salmon Company Limited (NZSC 30/2014) stated the importance of identifying areas of natural character and outstanding natural landscapes within the coastal environment to provide greater certainty for all involved when applying and considering consents. Emphasis on 'what is being protected' was also strongly highlighted. This paper considers the range of potential landscape and natural character effects of aquaculture under the Resource Management Act 1991 and Policies 13 and 15 of the New Zealand Coastal Policy Statement 2010. Specifically, this paper will focus on how landscape and natural character values are identified and protected through evolution of a robust methodology and best-practice descriptions of the characteristics and values of the area under consideration. Source

Stringer T.J.,University of Canterbury | Stringer T.J.,Landcare Research | Glover C.N.,University of Canterbury | Keesing V.,Boffa Miskell Ltd | And 2 more authors.
Ecotoxicology and Environmental Safety

Worldwide, estuaries are under increasing pressure from numerous contaminants. This study aimed to identify a suitable marine harpacticoid copepod species for toxicity testing of New Zealand estuaries. Multiple aspects were considered for species selection and included: a broad regional distribution, ease of culture, reproductive rate under laboratory conditions, sexual dimorphism, and sensitivity to contaminants. Five species were evaluated and two (Robertsonia propinqua and Quinquelaophonte sp.) were able to be cultured. The relative sensitivity of these copepods to three reference toxicants was assessed by determining the medial lethal values following a 96h exposure (96h LC 50) to these toxicants in the aquatic phase. LC 50 values for zinc, phenanthrene, and atrazine respectively were 2.0, 0.89, and 7.58mg/L in R. propinqua and 0.64, 0.75, and 20.8mg/L in Quinquelaophonte sp. After evaluating all factors involved in choosing a bioassay species for New Zealand, Quinquelaophonte sp. was selected as the most suitable bioassay species. © 2012 Elsevier Inc. Source

Harris D.B.,University Paris - Sud | Harris D.B.,University of Adelaide | Gregory S.D.,University Paris - Sud | Gregory S.D.,University of Adelaide | And 3 more authors.
Biological Invasions

Invasive rodents occur on over 80% of the world's island groups, invasions are continuing, and rodent impacts on insular wildlife have been well demonstrated. The extent of this problem calls for tools to aid large-scale prioritisation among the many candidate eradication operations. As conservation funds are limited, biologists have responded with prioritisation systems based on financial cost-effectiveness. Instead, we claim that long-term conservation gain should be the primary focus when prioritising islands for invasive rodent eradication. This concept is embodied mainly by invasive rodent reinvasion risk, which we categorise as natural or anthropogenic, based on the mechanism of reinvasion and our ability to mitigate the risk. The result is a first-pass triage system that prioritises eradication programmes by their long-term conservation potential, not their immediate value for money. To construct a prioritization list, we group islands into units for simultaneous eradication, to minimize inter-island reinvasion risk, and then assign weights to levels of unit reinvasion risk and unit conservation value. The choice of parameter weights may depend on capacity for biosecurity action (i. e. reduction in reinvasion risk) and a choice of tertiary filter variables can further discriminate within priority ranks. We illustrate our prioritization framework with a case study on rodents in New Caledonia but explain how our system can be adapted to suit any invasive rodent species or island configuration. © 2011 Springer Science+Business Media B.V. Source

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