Priority Threat Management

We developed Priority Threat Management in response to the need for timely action to save biodiversity. Priority Threat Management is a decision tool that identifies the threat management strategies that will recover the most species for the least cost. Our approach draws on empirical data and expert knowledge of major threats to biodiversity, the expected benefit of management to species recovery and persistence, along with the cost and feasibility of management.  Priority Threat Management can answer questions such as: How much will it cost to save all species in a region? How many species can be saved for a given budget? Which management strategies will save the most species for the least cost?  And which species irrespective of management are unlikely to be saved?

To date we have applied Priority Threat Management to 1/3 of the Australian continent, including a current application by colleagues to the entire state of New South Whales, along with case studies in Canada: South of the Divide Saskatchewan, and three current case studies in British Columbia: Fraser River Estuary, Kootenay Bioregion, and Central Coast Salmon.

Key Resources

Carwardine, J., T. G. Martin, J. Firn, S. Nicol, A. Reeson, L. Kehoe, H. S. Grantham, and I. Chades. 2018. A handbook on prioritizing threat management for biodiversity conservation. Journal of Applied Ecology DOI: 10.1111/1365-2664.13268.

Carwardine, J., T. O’Connor, S. Legge, B. Mackey, H. P. Possingham, and T. G. Martin. 2012. Prioritizing threat management for biodiversity conservation. Conservation Letters 5:196-204. PDF

Chadès, I., S. Nicol, S. van Leeuwen, B. Walters, J. Firn, A. Reeson, T. G. Martin, and J. Carwardine. 2015. Benefits of integrating complementarity into priority threat management. Conservation Biology 29:525-536.PDF

Firn, J., R. Maggini, I. Chadès, S. Nicol, B. Walters, A. Reeson, T. G. Martin, H. P. Possingham, J.-B. Pichancourt, R. Ponce-Reyes, and J. Carwardine. 2015. Priority threat management of invasive animals to protect biodiversity under climate change. Global Change Biology 21:3917-3930. PDF

Martin, T. G., L. Kehoe, C. Mantyka-Pringle, I. Chades, S. Wilson, R. Bloom, S. Davis, R. Fisher, J. Keith, K. Mehl, B. Prieto Diaz, M. Wayland, T. Wellicome, K. Zimmer, and P. A. Smith. 2018. Prioritizing recovery funding to maximize conservation of endangered species. Conservation Letters PDF

Trophic Cascades and Shifting Baselines

Trophic cascades ‘specify the effects of predators that propagate downward through food webs across multiple trophic levels’. Until recently, top predators were ubiquitous around the world. Today, their numbers are dwindling as a result of human persecution, triggering cascading effects of their disappearance in ecosystems, a process coined trophic downgrading, with unanticipated impacts on processes as diverse as wildfire, forest succession, carbon sequestration and invasive species. Daniel Pauly coined the term ‘shifting baselines’ to describe a phenomenon whereby we alter the world but forget what it was like beforehand, and each subsequent generation regards a progressively poorer natural world as normal.

For over a decade, we have been investigating the impact of trophic cascades and shifting baselines on island songbird and plant populations on islands off the coast of British Columbia within the Coastal Douglas Fir Zone, as a result of hyper-abundance of native and exotic deer following release from predation. This work is informing management within Parks Canada and in particular the Gulf Islands National Park Reserve and hunting regulations within the region.

Key Resources

Arcese, P., R. Schuster, L. Campbell, A. Barber, and T. G. Martin. 2014. Deer density and plant palatability predict shrub cover, richness, diversity and aboriginal food value in a North American archipelago. Diversity & Distributions 20:1368–1378. PDF

Martin, T. G., P. Arcese, P. M. Kuhnert, A. J. Gaston, and J.-L. Martin. 2013. Prior information reduces uncertainty about the consequences of deer overabundance on forest birds. Biological Conservation 165:10-17. PDF

Martin, T. G., P. Arcese, and N. Scheerder. 2011. Browsing down our natural heritage: Deer impacts vegetation structure and songbird assemblages across an island archipelago. Biological Conservation 144:459-469  PDF

Eco-Cultural Restoration

Indigenous peoples have shaped land and sea and the species therein through their resource stewardship over millennia. Within the Pacific Northwest, oral history and clear evidence of controlled burning, the farming of meadow ‘root’ gardens, Wapato, and hundreds of other plants, along with ‘clam garden’ aquaculture and other practices to promote beneficial species of cultural, spiritual, nutritional, and ecosystem importance abound. Yet, the scientific literature is sparse when it comes to understanding the role of these practices in the evolution and resilience of ecosystems and recovery of endangered species in particular.

Eco-cultural restoration supports the revitalization and continuation of traditional land use practices shaped by Indigenous communities over millennia. In partnership with Coast Salish First Nations we look forward to continuing to identify and develop the deep understanding of the historic practices which led to these tightly coupled human-ecological systems, of which Garry Oak ecosystems, now one of our most endangered ecosystems in Canada, is but one example. Together we will be searching out eco-cultural knowledge to restore this endangered ecosystem along with the ability to harvest species therein for individual and community use. In the spirit of reconciliation, this includes our work locally, where we are supporting the continuation and strengthening of land-based indigenous led cultural work taking place at Xwaaqw’um on Salt Spring Island.

Climate Change, Adaptation and Biodiversity Conservation

Climate change is impacting every level of biological organization and ecosystem process on earth. Our work is contributing to our understanding of:

Species and ecosystem vulnerability to climate change:

Foden, W. B., B. E. Young, H. R. Akçakaya, R. A. Garcia, A. A. Hoffmann, B. A. Stein, C. D. Thomas, C. J. Wheatley, D. Bickford, J. A. Carr, D. Hole, T. G. Martin, M. Pacifici, J. W. Pearce-Higgins, P. J. Platts, P. Visconti, J. E. M. Watson, and B. Huntley. 2018. Climate change vulnerability assessment of species. WIRES Climate Change DOI: 10.1002/wcc.551.n PDF

Martin, T. G., H. Murphy, A. Liedloff, C. Thomas, I. Chades, G. Cook, R. Fensham, J. McIvor, and R. van Klinken. 2015. Buffel grass and climate change: a framework for projecting invasive species distributions when data are scarce. Biological Invasions 17:3197-3210. PDF

Pacifici, M., W. B. Foden, P. Visconti, J. E. M. Watson, S. H. M. Butchart, K. M. Kovacs, B. R. Scheffers, D. G. Hole, T. G. Martin, H. R. Akcakaya, R. T. Corlett, B. Huntley, D. Bickford, J. A. Carr, A. A. Hoffmann, G. F. Midgley, P. Pearce-Kelly, R. G. Pearson, S. E. Williams, S. G. Willis, B. Young, and C. Rondinini. 2015. Assessing species vulnerability to climate change. Nature Climate Change 5:215-224. PDF

Scheffers, B. R., L. De Meester, T. C. L. Bridge, A. A. Hoffmann, J. M. Pandolfi, R. T. Corlett, S. H. M. Butchart, P. Pearce-Kelly, K. M. Kovacs, D. Dudgeon, M. Pacifici, C. Rondinini, W. B. Foden, T. G. Martin, C. Mora, D. Bickford, and J. E. M. Watson. 2016. The broad footprint of climate change from genes to biomes to people. Science 354. PDF

Interactive and cumulative effects of climate change with other threats:

Mantyka-Pringle, C. S., T. G. Martin, D. B. Moffatt, S. Linke, and J. R. Rhodes. 2014. Understanding and Predicting the Combined Effects of Climate Change and Land-Use Change on Freshwater Macroinvertebrates and Fish Journal of Applied Ecology 51:572-581. PDF

Mantyka-Pringle, C. S., T. G. Martin, and J. R. Rhodes. 2012. Interactions between climate and habitat loss effects on biodiversity: a systematic review and meta-analysis. Global Change Biology 18:1239-1252. PDF

Mantyka-Pringle, C. S., P. Visconti, M. Di Marco, T. G. Martin, C. Rondinini, and J. R. Rhodes. 2015. Climate change modifies risk of global biodiversity loss due to land-cover change. Biological Conservation 187:103-111. PDF

Restoring forests for both carbon sequestration and biodiversity benefits:

Carwardine, J., P. Polglase, A. Reeson, C. Hawkins, M. Watts, H. P. Possingham, and T. G. Martin. 2015. Spatial priorities for restoring biodiverse carbon forests. BioScience doi: 10.1093/biosci/biv008. PDF

Schuster, R., T. G. Martin, and P. Arcese. 2014. Bird Community Conservation and Carbon Offsets in Western North America. PLoS ONE 9:e99292. PDF

Pichancourt, J.-B., J. Firn, I. Chadès, and T. G. Martin. 2014. Growing biodiverse carbon-rich forests. Global Change Biology 20:382-393.PDF

Translocating species impacted by climate change:

McDonald-Madden, E., M. C. Runge, H. P. Possingham, and T. G. Martin. 2011. Optimal timing for managed relocation of species faced with climate change. Nature Climate Change 1:261-265.PDF

Schwartz, M., and T. G. Martin. 2013. Translocation of imperiled species under changing climates. Annals of the New York Academy of Sciences 1286:15-28. PDF

Conservation Decision Making Under Uncertainty

In an increasingly uncertain world, making good decisions regarding the protection of biodiversity is challenging. We have developed tools and frameworks for making such decisions in the context of uncertainty about the degree of climate change and its impact on biodiversity, timing of protection of critical habitat, recovering interacting endangered species, conserving migratory species and managing spatial networks of endangered species, invasive species and disease.

For example:

Chadès, I., J. M. R. Curtis, and T. G. Martin. 2012. Setting realistic recovery targets for interacting endangered species. Conservation Biology 26:1016-1025 PDF

Chadès, I., T. G. Martin, S. Nicol, M. Burgman, H. P. Possingham, and Y. Buckley. 2011. General rules for managing and surveying networks of pests, diseases and endangered species. Proceedings of the National Academy of Sciences 108:8323-8328. PDF

Flockhart, D. T. T., J.-B. Pichancourt, D. R. Norris, and T. G. Martin. 2015. Unravelling the annual cycle in a migratory animal: breeding-season habitat loss drives population declines of monarch butterflies. Journal of Animal Ecology 84:155-165. PDF

Martin, T. G., A. E. Camaclang, H. P. Possingham, L. A. Maguire, and I. Chadès. 2017. Timing of Protection of Critical Habitat Matters. Conservation Letters 10:308-316. PDF

Martin, T. G., I. Chadès, P. Arcese, P. P. Marra, H. P. Possingham, and R. Norris. 2007. Optimal conservation of migratory species. PLoS ONE 2:e751.PDF

McDonald-Madden, E., M. C. Runge, H. P. Possingham, and T. G. Martin. 2011. Optimal timing for managed relocation of species faced with climate change. Nature Climate Change 1:261-265. PDF