Browsing by Author "Makan T"

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    Simulating Demography, Monitoring, and Management Decisions to Evaluate Adaptive Management Strategies for Endangered Species
    (Wiley, 2025-04-02) Canessa S; Converse SJ; Adams L; Armstrong DP; Makan T; McCready M; Parker KA; Parlato EH; Sipe HA; Ewen JG
    Adaptive management (AM) remains underused in conservation, partly because optimization-based approaches require real-world problems to be substantially simplified. We present an approach to AM based in management strategy evaluation, a method used largely in fisheries. Managers define objectives and nominate alternative adaptive strategies, whose future performance is simulated by integrating ecological, learning and decision processes. We applied this approach to conservation of hihi (Notiomystis cincta) across Aotearoa-New Zealand. For multiple extant and prospective hihi populations, we jointly simulated demographic trends, monitoring, estimation, and decisions including translocations and supplementary feeding. Results confirmed that food supplementation assisted recovery, but was more intensive and expensive. Over 20 years, actively pursuing learning, for example by removing food from populations, provided little benefit. Recovery group members supported continuing current management or increasing priority on existing populations before reintroducing new populations. Our simulation-based approach can complement formal optimization-based approaches and improve AM uptake, particularly for programs involving many complex and coordinated decisions.
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    To translocate or not to translocate? Embedding population modelling in an inclusive structured decision-making process to overcome a conservation impasse
    (John Wiley and Sons Ltd on behalf of the Zoological Society of London, 2024-07-20) Parlato EH; Fischer JH; Steeves TE; Graydon K; Kennedy E; Makan T; Patterson E; Thurley T; Welch J; Parker KA; Ewen J; Petracca L
    The need for effective conservation strategies to combat the ongoing biodiversity crisis is well recognised. Conservation translocations are an important and frequently used form of conservation management for species recovery. Despite this, the uncertainty prevalent throughout the translocation cycle often makes it challenging to determine whether translocations should be included in the suite of actions to achieve desired conservation outcomes. Further, the fundamental question of whether translocations should occur is seldom assessed as a formal decision. We applied a formal decision analysis for the conservation management of a highly threatened bird (karure | kakaruia | Chatham Island black robin | Petroica traversi) to evaluate whether translocation and/or other actions should be implemented for species recovery. The species' precarious status (<330 adults), combined with uncertainty about translocation outcomes, meant that for years, decision-makers were reluctant to act given the potentially severe consequences of translocation failure. We used structured decision-making in conjunction with population modelling to estimate the consequences of translocations and other actions across a range of objectives identified by Moriori and Ngāti Mutunga o Wharekauri (Indigenous Peoples of Rēkohu | Wharekauri | the Chatham Islands), the local community and government agencies. Structured decision-making facilitated an inclusive approach that ensured all participants were actively engaged in the decision-making process including the identification of the best management alternative while balancing multiple objectives. This process overcame the long-standing conservation impasse, resulting in rapid implementation of actions, including translocation, that would have otherwise been difficult to achieve. The preferred alternative across objectives involved multiple translocations, illustrating the vital role translocations have in the desired future management for the species. The methods used in our study can be readily applied in other species recovery programmes to help decision-makers navigate the complexities and uncertainties inherent in conservation decisions.
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    Ventral dermatitis in rowi (Apteryx rowi) due to cutaneous larval migrans.
    (2015-04) Gartrell BD; Argilla L; Finlayson S; Gedye K; Gonzalez Argandona AK; Graham I; Howe L; Hunter S; Lenting B; Makan T; McInnes K; Michael S; Morgan KJ; Scott I; Sijbranda D; van Zyl N; Ward JM
    The rowi is a critically endangered species of kiwi. Young birds on a crèche island showed loss of feathers from the ventral abdomen and a scurfy dermatitis of the abdominal skin and vent margin. Histology of skin biopsies identified cutaneous larval migrans, which was shown by molecular sequencing to be possibly from a species of Trichostrongylus as a cause of ventral dermatitis and occasional ulcerative vent dermatitis. The predisposing factors that led to this disease are suspected to be the novel exposure of the rowi to parasites from seabirds or marine mammals due to the island crèche and the limited management of roost boxes. This is the first instance of cutaneous larval migrans to be recorded in birds. Severe and fatal complications of the investigation resulted in the death of eight birds of aspergillosis and pulmonary complications associated with the use of bark as a substrate in hospital. Another bird died of renal failure during the period of hospitalisation despite oral and intravenous fluid therapy. The initiating cause of the renal failure was not determined. These complications have the potential to undermine the working relationship between wildlife veterinarians and conservation managers. This case highlights that intensive conservation management can result in increased opportunities for novel routes of cross-species pathogen transmission.