Queensland has traditionally used nets and baited-hook drumlines to protect beachgoers from sharks, but this method has resulted in the deaths of many marine animals, including sharks, turtles, dolphins, and dugongs. Last year, 958 animals, including 798 sharks, were caught in the equipment, with 70% of them dying. In 2022, 15 humpback whales were also caught, but all of them were successfully released.
The government is now testing the use of camera-equipped drones to search for sharks as a potential replacement for these lethal methods. Rob Adsett, the chief remote pilot with the Australian Lifeguard Service, has noted that it is easy to spot sharks from the air, and the technology is constantly improving. The trial program, which is being conducted in places like Alexandra Headland, has shown promising results so far.
Based on statistics, in 2021, there were 73 confirmed unprovoked cases of shark attacks worldwide, which is consistent with the average of 72 incidents per year over the previous five-year period. However, the number of unprovoked cases decreased significantly in 2020, which is thought to be due to lockdowns related to the COVID-19 pandemic. There were 11 fatalities from shark attacks this year, 9 of which were classified as unprovoked.
Shark Conservation Efforts
This is higher than the average of 5 unprovoked fatalities per year. It is common for the number of shark-human interactions to vary from year to year. Despite the recent increase in fatalities, long-term trends show a decreasing number of annual fatalities. The local abundance of sharks and humans in the water can be influenced by a range of factors, including oceanographic, socioeconomic, and meteorological conditions.
Adsett and his team used an infrared-equipped drone that can fly for 20 minutes in strong winds to patrol the beach at Alexandra Headland. The drone follows a 400-meter route parallel to the shore, flying at a height of 60 meters and speeds of up to 20 kilometers per hour on busy days. If a shark is detected, the pilots lower the drone to 30 meters to identify the size and species of the animal. If the shark is deemed a threat, the beach can be evacuated and lifeguards can follow in boats or personal watercraft to track and monitor the shark.
During trials in 2020 and 2021, the drone pilots conducted 3,669 flights at seven beaches and detected 174 sharks, including 48 that were over two meters in length. These larger sharks, including white, tiger, and bull sharks, are the most concerning for beachgoers and lifeguards and led to four beach evacuations.
Australia's Drone Program
Queensland's drone program follows a similar initiative in New South Wales, which has been in operation since 2017. Conservationists are eager for the switch away from nets and drumlines to be implemented as soon as possible. Leo Guida, a shark scientist with the Australian Marine Conservation Society, believes that any further delay in replacing these lethal methods with drones is "baffling," as the solution is already available. Drones can also be used to deliver life-saving equipment to people in distress in the water. Adsett also notes that the risk of being attacked by a shark while at the beach is low compared to the risk of being hit by a car while traveling to the beach.
Although shark bites are relatively rare, the rate of attacks is increasing. The Australia Shark Incident Database recorded 1,196 shark bites in the country from 1791 to 2022, resulting in 250 deaths and 723 injuries. The remaining 223 cases did not result in injury and involved incidents such as bites on surfboards. The number of shark bites per year increased from an average of 9 in the 1990-2000 decade to 22 in the 2010-2020 decade, partly due to the growing human population along the coast.
However, Guida points out that even nets and drumlines are not always effective at preventing bites, as sharks can swim around them. This was the case in 2020 when a male surfer was killed by a shark bite at Greenmount Beach, which was protected by nets and drumlines. Despite these challenges, the Queensland government is committed to expanding its drone trial program, which will continue through June 2025 at a cost of approximately $1.3 million per year.
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