Anna Hartz
If you are surfing or swimming in Hawaii, there is one month when you should be extra cautious: October.
The month has earned the nickname “Sharktober” because shark bites happen more often then than any other time of the year. A new study now confirms that there is truth to the idea.
30 Years of Data
Researchers looked at 30 years of shark bite data in Hawaii from 1995 to 2004. They found that roughly 20 percent of all unprovoked bites occurred in October. This is two to four times more than in any other month, writes Videnskab.
One shark species stands out. Tiger sharks were responsible for 47 percent of all recorded bites during the entire period. In October, the number was even higher. At least 63 percent of the bites that month were caused by tiger sharks.
Tiger sharks usually grow between 3 and 4.3 meters long and can weigh more than 385 kilos. Young tiger sharks have dark, vertical stripes on their bodies, which fade as they age. These sharks are found in temperate and tropical oceans worldwide, but they are especially common around Pacific islands, including Hawaii.
Baby Sharks in October
Marine biologist Carl Meyer from the University of Hawai’i explains that the October spike is not because more people are in the water. He points to shark biology. Female tiger sharks give birth at this time of year. The mothers move closer to shore to deliver their young. This increases the number of large tiger sharks in areas where humans swim and surf.
Tiger sharks give birth to live pups. The eggs hatch inside the mother, and she usually has about 30 pups after 15 to 16 months of pregnancy. Giving birth takes a lot of energy, which may make the sharks more active and more likely to encounter people.
Other factors, like the amount of prey in the area, may also influence tiger shark behavior.
Even though the risk of a shark bite is higher in October, such incidents are still very rare. “The most important thing is awareness, not panic,” says Meyer. He recommends extra caution during this month, especially if you surf alone or swim close to the shore.
Sources: Videnskab
