Journal: Conservation Biology
Blog author: Jessica Rowland
Citation: Rowland, J.A., Nicholson, E., Murray, N.J., Keith, D.A., Lester, R.E. and Bland, L.M., 2018. Selecting and applying indicators of ecosystem collapse for risk assessments. Conservation Biology.
Ecologists and managers carry out risk assessments to inform how to best monitor and manage ecosystems. Risk assessments can identify areas or aspects of ecosystems that are at risk of degradation or collapse, by measuring change in variables that reflect vital parts of the ecosystem – known as indicators. Despite risk assessments being widely applied, there is little guidance on selecting and using indicators in a consistent, and transparent way to ensure assessments are reliable and repeatable.
Jess Rowland, along colleagues from our research group and collaborators, reviewed ecological studies and risk assessments that applied the IUCN Red List of Ecosystems (RLE) in marine and terrestrial ecosystems to understand the strengths and shortcomings in the selection and use of indicators. In particular, we were interested in how indicators were selected, and which parts of ecosystems they reported on, specifically change in area of ecosystems, in abiotic aspects (such as annual temperature or precipitation) and in biotic components (such as abundance of key native species or invasive species).
We found that the process of selecting indicators was rarely reported, and it was not common to use indicators representing all three of area, and biotic and abiotic features. The types of indicators used varied between marine and terrestrial ecosystems, showing a greater focus on ecosystem functionality in marine ecosystems and area in terrestrial ecosystems. In several ecological studies using multiple indicators, indices or multivariate analyses were used to assess the indicators simultaneously. On a positive note, most used time-series data spanning at least 30 years, increasing the chance of detecting change.
The main message from this research is there are several ways in which ecosystem assessments can improve. To support ecological research and managers, we created a guide the key steps in selecting suitable indicators. Reliable and repeatable risk assessments require assessors to clearly outline how and why indicators were selected, the source and quality of the data used, and to use indicators that wide-ranging set of indicators that capture different types of ecosystem change. Otherwise, the chance of inaccurate results in risk assessments increases.
Our guide aims to help ecologists and managers to produce reliable risk assessments that can be used to support timely and suitable decisions to ensure ecosystems are effectively managed.
Rufous Whistler (Photo credit: Mark Gillow via Flickr.)