Quantitative assessment of supplementary feeding as an adaptive conservation management strategy for red-billed choughs.

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Successful conservation of wildlife populations requires effective management policies to be enacted by government and non-government agencies, thereby maintaining wildlife's intrinsic, cultural and economic benefits. One key paradigm is adaptive management, where i) scientific understanding of ecological and demographic drivers of population change is used to plan and implement management; ii) impacts on population ecology, demography and dynamics are quantified; iii) resulting evidence is used to plan subsequent management. However, such adaptive management is rarely enacted, not least because high-quality data quantifying short-term and longer-term impacts of initial management are rarely collected or rigorously analysed, eroding the evidence-base for future policy.This project provides an outstanding multidisciplinary training opportunity for a PhD student to develop an exemplary adaptive management model for one of the UK's most endangered birds, the red-billed chough. The student will rigorously evaluate effects of a key management intervention, supplementary feeding, applied in a Scottish chough population of major conservation concern. They will work alongside government conservation agency staff involved in research, policy and operation, and stakeholders and academics, to use resulting evidence to decide future conservation policy. The project will thereby train a new scientist to drive science-policy convergence, advancing society's ability to conserve valued wildlife populations through adaptive management.Provision of supplementary food is a key management tool for food-limited target populations. However, althoughvertebrate population dynamics are commonly constrained by low sub-adult and adult survival, supplementary feeding regimes typically focus instead on increasing breeding success. Despite its potential as a key management tool, few experimental or management interventions have fed sub-adults, or evaluated short-term effects on sub-adult survival. Further, such feeding could have profound longer-term effects by altering sub-adult dispersal, age at first breeding or subsequent reproduction. However, no studies have quantified such effects or hence evaluated overall effects ofsupplementary feeding of sub-adults on population growth rate. Scotland's remaining chough population is limited to Islay and Colonsay and is of major conservation concern and socioeconomicvalue due to eco-tourism, cultural significance and links to low-intensity pastoral agriculture. Scottish Natural Heritage (SNH), Scotland's statutory conservation agency, is obliged to undertake appropriate management action.Analyses of high-quality demographic data for 1983-2009 showed that variation in chough population size largely reflects variation in sub-adult survival, and very high sub-adult mortality during 2007-2009 threatened population viability. SNH therefore funded a programme of supplementary feeding of sub-adult choughs and associated demographic monitoring. A subset of sub-adults on Islay were/will be fed daily during July-April 2010-2018, by Scottish Chough Study Group (SCSG). Detailed ring resighting and nest monitoring data have been collected to allow survival, dispersal and reproduction of fed and unfed individuals to be quantified.The PhD student will use this truly remarkable multi-year dataset to comprehensively assess effects of supplementary feeding of sub-adults on demography and population growth rate using Before-During-Control-Impact (BDCI) analyses encompassing 1983-2019. They will work with SNH and SCSG (CASE and project partners) to use their results to decide future feeding policy in the wider context of habitat management enacted by the Scottish Rural Development Programme. They will thereby undertake excellent science to quantify effects of a novel form of supplementary feeding, and directly influence conservation policy and practice for a rare bird for which UK governments are responsible.