Overview
- A University of St Andrews-led team introduced a population-level metric called “overlap intensity” in the Journal of Applied Ecology to gauge how many penguins are affected when fishing vessels operate nearby.
- Tracking data from Robben and Dassen Islands showed overlap peaked at about 20% in the low biomass year of 2016, compared with roughly 4% in years with healthier fish stocks.
- Competition with purse-seine vessels intensifies when sardines and anchovies are scarce, with the highest risk during chick-rearing when adults must find food quickly.
- African penguin numbers have fallen by nearly 80% over three decades as fisheries target the same schooling prey that penguins rely on.
- After a high-court settlement earlier this year, South Africa reinstated no-fishing zones around Robben Island, and the study’s evidence supports dynamic, ecosystem-based closures during sensitive periods.