Researchers at the Zoological Society of London (ZSL) have discovered that sharks are much less likely to be found in coastal habitats close to human populations and fishing fleets, where they are frequently killed for their meat and fins. In addition, the team found that the average body size of sharks and other marine predators is dramatically reduced near coastal areas with more than 10,000 people.
The study revealed that sharks needed a distance of at least 775 miles from cities and fish markets to escape the damaging effects of human activities. This is a much larger distance than previous estimates, which can likely be explained by the fact that fishing boats are now travelling farther. For this reason, the researchers only observed sharks in 12 percent of the monitoring sites.
The experts noted that sea surface temperatures also had a strong influence on the average body size of marine predators, with a marked decrease at more than 82 degrees Fahrenheit, which may become an issue as global temperatures continue to rise.