The Florida horse conch population – one of the world’s largest invertebrate animals – is shrinking.
Established in 1969 as the Florida State Shell, it has become symbolic of Florida’s natural resources, yet unregulated commercial harvesting and recreational live collection are pushing populations closer to collapse.
Data from Florida Fish and Wildlife Conservation shows that there has been a steady population decline since the mid-1990s. Commercial fishermen reported a peak count of 14,511 Florida horse conchs in 1996, followed by 6,124 in 2000, 1,461 in 2015 and just 67 in 2020.
According to Greg Herbert, associate professor from the University of South Florida School of Geosciences, “Horse conch populations are important. They create habitat for other species by leaving empty shells of dead prey around for fish, crabs and other animals to use as homes. They also contribute to the unique experience that we have in Florida of being able to go to the beach and seeing one of the largest seashells in the world at the water’s edge.”
“We still know very little about how many horse conchs exist and where their preferred habitats or what their optimal environmental conditions are,” said Stephen Geiger, research scientist at the FWC. “Because we have no dedicated funding for more than 1,500 species of mollusks found in the waters that surround Florida, we continue to seek grants that enable us to study their biological traits, including those that will help managers decide if some species are in need of better protection.”
Such a grant led to a study by the University of South Florida, who concluded the average lifespan of a Florida horse conch is between eight and 10 years old, and it doesn’t start reproducing until about age six, when they give birth to up to 28,000 offspring each year. This is a dramatic shift from previous belief that a horse conch could live for half a century -– meaning far fewer offspring are born to replace those removed as a result of harvest or natural causes.