Tiger Shark Habitats Revealed as Biologist Claims Species Is Getting Bigger

Researchers have revealed new insights into the movements of tiger sharks and their favorite hangouts in the Gulf of Mexico.

According to a study published in the journal PLOS ONE, the scientists documented significant differences in how the sharks were distributed and moved across the Gulf depending on their life stage, the season or their sex.

For example, the researchers identified certain key regions that tiger sharks, particularly females, flocked to during the cooler months.

These regions encompass sections of the Gulf designated as "Habitat Areas of Particular Concern" by the National Oceanographic and Atmospheric Administration, which are mostly found off the coast of Louisiana and are often associated with ocean banks, including Flower Garden Banks National Marine Sanctuary and Jakkula Bank.

Habitat areas of particular concern are essential fish habitats considered to be especially important ecologically or particularly vulnerable to human impacts.

In addition, the researchers found that the key regions for the tiger sharks overlapped with more than 2,500 oil and gas platforms in the Gulf.

Tiger sharks travel large distances, often crossing regional, national and international boundaries. However, their range and use of habitats in the Gulf remains poorly understood.

To study sharks in the region, a team led by Matt Ajemia from Florida Atlantic University's Harbor Branch Oceanographic Institute fitted 56 tiger sharks with monitoring tags between 2010, the year of the devastating Deepwater Horizon Oil Spill, and 2018.

These tags, which are fitted to the sharks' fins, emit a signal whenever they emerge above the surface of the water. Satellites collect these signals, enabling researchers to track the movements of the sharks, providing unique insights into their movements and distribution.

Unlike previous research on tiger sharks in the region that has only looked a one sex at a time, Ajemia and his team tracked males of female of varying life stages, observing sex and size-specific differences in their distribution and movements.

"While all life stages of tiger sharks are known to occur in the Gulf of Mexico, detailed habitat use has never been quantified," Ajemian said in a statement. "This is rather striking as this marine system faces numerous man-made stressors [and] complex tri-national management."

tiger shark
A tiger shark. NOAA

The latest study has been published as a marine biologist said that the species is getting bigger and bigger every year in one region of the South Pacific at least.

Kori Garza, who is currently filming in the South Pacific for a National Geographic documentary titled World's Biggest Tiger Shark, believes that a shark fishing ban implemented by French Polynesia in 2006 could be one potential factor.

The ban has meant that there are now plenty of smaller species for the tiger sharks in the area to eat, enabling them to grow larger, she said.

"I think it is possible that in healthier ecosystems, especially in these remote areas, there's not a lot of impact from the outside," she told The i News. "You have to have a lot of resources for an animal to get that big."

During her dives, she encountered a huge tiger shark known as Kamakai, which is thought to be the biggest of the species ever recorded.

"When we were alone with the others, we thought they were pretty big... and then this giant submarine of a shark came along and made the other ones look like little chihuahuas."