How common are hammerhead sharks in Florida waters?

Days after a 15-foot hammerhead shark was caught in Pompano Beach, NBC 6 wanted to get an update on the health of this species in ocean waters.

Although the hammerhead shark is not listed as an endangered species by the U.S. Fish & Wildlife Service, it is listed as critically endangered by the IUCN Red List of Threatened Species since 2019.

The International Union for Conservation of Nature’s (IUCN) Red List of Threatened Species classifies species at high risk of global extinction and to date has assessed more than 163,000 species.

Some of the challenges these animals face worldwide are excessive fishing and bycatch by commercial fishing vessels as well as rising ocean temperatures, loss of habitat and declining food supply, according to the IUCN’s website.

However, right here in South Florida we have the only "described" or "established" nursery for great hammerheads, the first of its kind identified on the entire American Atlantic coast, according to Catherine Macdonald, professor at the Rosenstiel School of Marine, Atmospheric and Earth Science from the University of Miami.

A “nursery” is an area where sharks are either born or spend the early years of their lives.

Macdonald and her team published their findings in the journal Conservation Science and Practice in 202, and they are still carrying out this research today.

“We study the biology and ecology of more than 10 species of shark in Biscayne Bay, and the Bay's importance to many of these species as reproductive habitat, including as nurseries. For juvenile great hammerheads, we are very excited to be learning more about their essential habitats, movement, and diet in their early years of life,” said Macdonald in an email to NBC6.

Great hammerheads, the largest kind of hammerhead shark, are one of the most iconic carnivores to swim the Florida coastline. Great hammerheads are very recognizable but hardly ever pose any risk to humans.

In Florida it is illegal to "harvest" or "land" any species of hammerheads, but they can be caught in federal waters. Retention of hammerheads is legal in federal waters around Florida in compliance with federal fisheries regulations.

“If you accidentally catch a hammerhead,” Macdonald told NBC6, “the best thing you can do for them is minimize fight time and handling time.”

The most common practice is catch and release.

Great hammerhead populations have declined dramatically since the mid-20th century. Populations have begun to show early signs of recovery in recent years in this region, according to Professor Macdonald.

“Sharks are generally slow-growing and slow-reproducing, so it can take many years for a female shark to reach maturity and begin producing pups. These reproductive characteristics are a key reason why shark populations are generally slow to recover from overfishing and population declines,” Macdonald said.