Method to Foresee Animals' Population Collapse

(University of Zurich, June 19, 2017)

Researchers from the University of Zurich and the University of Tasmania analyzed data on the commercial whale fishing in the 20th century which led to collapses in the population through overharvesting. The team was the first to show in a wild population that extreme changes in the average body size together with fluctuations in the number of individuals in a population, as earlier experimental research showed, give indications for a collapse. Investigating historic data on blue, fin, sei and sperm whales, they found a remarkable decrease in the physical size. An average sperm whale was four meters short in the 1980s than in 1905. The results indicate that monitoring the average body size in populations could help predicting a potential collapse. This method could also be used for other species, as the growing human population is endangering animals' population.