Does aquaculture create ecological traps for wildlife?
With aquaculture industries expanding around the world, there are growing concerns about their environmental impacts and effects on wildlife. Aquaculture farms are thought to either repel, act as a population source, or act as an attractive population sink (or ecological trap) for a variety of species. To assess the state of knowledge on the impacts of aquaculture on wildlife worldwide, researchers from the University of Melbourne led by Dr. Luke Barrett conducted a review and meta-analysis of empirical studies to better understand the outcomes of interactions between aquaculture operations and wildlife. Effects of aquaculture on wild populations depended on the wild taxa and farming system. Overall, farms were associated with a higher local abundance and diversity of wildlife, but this effect was mostly driven by aggregations of wild fish around sea cages and shellfish farms. Birds were also more diverse at farms, but other taxa, such as marine mammals, showed variable and comparatively small effects. While they identified evidence for widespread aggregation ‘hotspots’ in several systems, the authors also found that very few studies collect the data needed to assess impacts of aquaculture on the survival and reproduction of farm-associated wildlife. Such data will be crucial for determining whether the behaviour of aggregating around farms results in higher or lower population growth for farm-associated wildlife.
To read the full article, click here.