Particle.news
Download on the App Store
5 ARTICLES
·
2mo ago

NSW Councils Phase Out Shark Nets as Bull Sharks Linger Longer Off Sydney Coast

Scientists link a two-week seasonal extension in shark visits to warming seas that may make bull sharks a year-round presence

Bull sharks are lingering off Sydney's beaches for longer periods each year as oceans warm, researchers say, predicting they may one day stay all year
Shark attacks are rare in ocean-loving Australia, and most serious bites are from three species: bull sharks, great whites, and tiger sharks, according to a national data base
Image

Overview

  • Analysis of tagging data shows bull shark season in Sydney Harbour has grown by 15 days since 2009, averaging one extra day per year.
  • Over the past 40 years, mean sea temperatures during shark season have climbed by 0.67°C, eroding the thermal trigger for sharks’ northward migration.
  • Researchers warn that if current warming trends persist, bull sharks could remain in Sydney waters year-round within a few decades.
  • Peak activity persists in mid-summer when large females swim up Hawkesbury and Parramatta estuaries to give birth.
  • In response to rising interaction risks, NSW councils and the state government are replacing shark nets with drone surveillance systems and SMART drumlines.