Targeted management buffers negative impacts of climate change on the hihi, a threatened New Zealand passerine

Abstract

In order to buffer the risks climate change poses to biodiversity, managers need to develop new strategies to cope with an increasingly dynamic environment. Supplementary feeding (SF) is a commonly-used form of conservation management that may help buffer the impacts of climate change. However, the role of SF as an adaptation tool is yet to be fully understood. Here we used the programme MARK to quantify the relationship between weather (average temperature and total precipitation) and vital rates (survival and recruitment) of an island bird population, the hihi Notiomystis cincta, for which long term demographic data are available under periods of little and ad libitum SF. We then used predictive population modelling to project this population's dynamics under each management strategy and several climate change scenarios in accordance with the Intergovernmental Panel on Climate Change predictions. Our stochastic population projections revealed that ad libitum SF likely buffers the population against heavier rainfall and more stochastic precipitation patterns; no buffering effect on temperature was detected. While the current SF approach is unlikely to prevent local extinction of the population under increasing temperatures, SF still presents itself as a valuable climate change adaptation tool by delaying extinction. To the best of our knowledge, this is the first study to quantify the interaction between climate and SF intensity of a threatened population. We call for on-going critical evaluation of management measures, and suggest that novel adaptation solutions that combine current approaches are required for conserving species with limited opportunity for dispersal.

Shifting the conservation paradigm: a synthesis of options for renovating nature under climate change

“…For example, reducing natural parasite infestations in chicks of a rare Tasmanian Albatross is compensating for reductions in breeding success due to the warming climate (Alderman and Hobday ); and simulations suggest supplemental feeding of threatened New Zealand his ( Notiomystis cincta Du Bus, 1839) could delay their extinction under climate change (Correia et al. ).…”

“…Parallel to the concept of ameliorating anthropogenic stressors (see 9C1-2), managing natural stressors such as natural diseases or resource-availability gaps, is a creative, climate-targeted measure occasionally recommended to buffer target species or communities from climate stress (0.8% of instances). For example, reducing natural parasite infestations in chicks of a rare Tasmanian Albatross is compensating for reductions in breeding success due to the warming climate (Alderman and Hobday 2017); and simulations suggest supplemental feeding of threatened New Zealand his (Notiomystis cincta Du Bus, 1839) could delay their extinction under climate change (Correia et al 2015).…”

The stepping‐stone approach is promising but we need so much more

“…Lloyd et al (2019) cleverly design their multi-year capture-mark-recapture experiment in order to compare the annual survival, and survival to prime-breeding age (PBA) of three treatment groups: wild-to-wild, captive-to-wild and captive-intermediate site-wild (stepping-stone treatment). Chauvenet et al, 2012;Correia et al, 2015). However, there are two aspects of the work I want to discuss: (1) how stepping-stone effectiveness is measured and (2) how this work scales up to other systems.…”

“…I would be interested to see a population model that integrates their demographic results and shows the long-term benefits of the stepping-stone approach developed (see e.g. Chauvenet et al, 2012;Correia et al, 2015).…”

Changes in density of hihi (Notiomystis cincta), tīeke (Philesturnus rufusater) and tūī (Prosthemadera novaeseelandiae) on Little Barrier Island (Te Hauturu-o-Toi), Hauraki Gulf, Auckland, 2005–2013

“…Despite lack of current significant predation pressure and a high diversity and abundance of food sources the low densities of hihi recorded during 2010-2013 (0.83-1.1 hihi ha −1 ) are of considerable concern. Little Barrier Island supports the only self-sustaining population of hihi and a low-density population is at risk of significant loss due to short-term stochastic events such as storms, moderate-term threats due to invasion of predators or disease and longer-term gradual changes occurring through climate change (Correia et al 2015). We therefore recommend continued population monitoring of the hihi population using distance sampling and investigation of the environmental factors that determine population density.…”