Abundance estimates are used both directly and indirectly in stock assessment processes to support fishery management. Each estimation method has benefits, biases and caveats depending on context and species being assessed. As the application of each method of estimating abundance is potentially species/scenario specific, potential use by researchers and managers can be fraught. We reviewed a wide range of methods used to estimate abundance of fishery species, including finfish and shellfish. Information on each approach was collated and matched against some 50 criteria (or questions) which can be used to filter and select a subset of suitable methods.
We have developed an R-shiny tool that allows investigation of 18 methods of estimating abundance for management purposes, the conditions of use, and any limitations for operational use. Based on the use case, there are five entry points in the tool. These range from a simple side-by-side comparison of methods, to applying high level filters based on need, to screening based on context or preferred method subset, to undertaking a full diagnostic questionnaire to receive tailored advice. Results from each investigation can be exported for further exploration and reporting.
The tool brings together information in an accessible and interactive format to allow: i) rapid review of techniques available to estimate abundance; ii) evaluation of suitability of techniques to different conditions such as life history, and data availability; iii) comparison of the requirements of the technique such as methods used, prerequisite expertise, data and cost; and iv) consideration of the circumstances under which the technique can be used.
We here present the tool and discuss its potential application and possible extensions.