Classification of Non-Indigenous Species Based on Their Impacts: Considerations for Application in Marine Management

Ojaveer, H. et al. Classification of Non-Indigenous Species Based on Their Impacts: Considerations for Application in Marine Management. PLOS Biology 13, e1002130 (2015). PDF.

Summary

A framework for classifying magnitude of impacts of marine non-indigenous species (NIS) is needed due to many differences between marine and terrestrial systems. They address the misconception that lack of statistical significance is evidence of safety. Lack of knowledge/data on native marine biota and NIS leads to a non-precautionary approach. Given the infeasibility of removal of marine NIS once they are established, they advocate for a precautionary approach using an assessment scheme with four criteria: environmental, economic, social/cultural, and human health.

Take home points

• Marine systems are sufficiently different from terrestrial systems that a separate impact risk classification is needed. 

• Impacts and feasibility of removal is better understood in terrestrial systems, however lack of lack of evidence for impacts in marine systems should not be equated to evidence for safety . 

• Lack of research and data marine NIS impacts is a challenge for managers. 

Management implications

• Removal of established marine NIS is nearly impossible so management should be precautionary: focus on invasion vector management.

• An initial assessment of no impact makes later adaptive management more difficult, for example revoking aquaculture rights once a NIS has documented impacts. 

Keywords

Management efficacy; Impact studies; Marine non-indigenous species; data-deficiency