Scaling up invasive species control strategies: from small community-led blocks to landscape scales

20 April 2012

Dr Andrea Byrom (Research Portfolio Leader - Weeds, Pests & Diseases, Manaaki Whenua / Landcare Research, New Zealand) hosted by Peter Banks

Management of invasive species is rarely conducted at a landscape scale (i.e. tens of thousands of hectares). More typically, pests are managed intensively in patches that are deemed to be of high importance, with little or no management in the surrounding matrix. This may lead to persistence of some native biota only in areas where invasive animals are controlled, with occasional dispersal between patches. This is known in ecological theory as a metapopulation.

How can we strengthen the metapopulation approach to improve outcomes of invasive species management for native biodiversity? Increasingly, community conservation initiatives in New Zealand and Australia are involved in preserving, restoring and even re-introducing native biota, often in small patches in their 'backyard. Therefore, one of the most obvious practical means of adopting a metapopulation paradigm is to use such community-led blocks as source areas or stepping stones, in order to manage invasive species and native biota at a landscape scale. This means that both large and small sites, from small community-led initiatives to large-scale agency-funded pest control operations, all have the potential to contribute to survival of the metapopulation, with immigrants from neighbouring patches providing a 'rescue effect'. The resilience of the metapopulation is therefore much greater than that of a single, isolated population.

With the aid of several practical examples, we show that in New Zealand and Australia we can, with smarter use of existingpest control tools, start to think big, and that we can establish integrated networks of pest management zones that facilitate dispersal of native species through landscapes. Conversely, pest control programmes can be designed to reduce connectivity for invasive species. The goal is to improve the timing and location of pest control to promote metapopulations of native species, re-establish large-scale ecosystem processes, and hence provide greater overall benefits for biodiversity.

Time: 4-5pm

Location: DT Anderson Lecture Theatre, A08