Seashells may seem like harmless souvenirs from a beach trip, but scientists point out reasons not to take them home.
A 2014 study reported by IFL Science on May 18 highlighted that scientists investigated the removal of seashells from beaches and concluded that this action causes “significant harm” to many species that rely on seashells.
Seashells on the beach. (Photo: Javel Williams/Shutterstock.com).
Seashells are a crucial link in coastal ecosystems. In addition to stabilizing beaches and providing materials for birds to build nests, they also offer habitat or attachment surfaces for many marine organisms, including algae, seagrasses, sponges, and various crustaceans. They serve as a source of calcium carbonate, which can dissolve in seawater and be recycled back into the ocean.
Michal Kowalewski, the lead author of the study and a paleontologist at the Florida Museum, stated that “Seashells are important because they serve numerous functions in natural ecosystems.”
Geerat Vermeij, a mollusk shell expert and a prominent geology professor at the University of California, Davis, who was not involved in the study, added that mollusk shells are vital for hermit crabs. Although sandy beaches are not ideal habitats for these crabs, dead shells on mudflats and rocky shores are a primary resource for many hermit crab species. Furthermore, many small organisms settle on dead seashells, thus “removing these shells will also eliminate the habitat of these organisms,” Vermeij stated.
The researchers conducted several monthly surveys from 1978 to 1981 and from 2008 to 2010 at Llarga Beach, located about an hour’s drive from Barcelona, Spain. The results showed that the number of shells had decreased by up to 60% between the two study periods.
They suspect that the disappearance of seashells is likely due to the influx of tourists to the area, as the number of shells tends to be higher in winter when fewer tourists visit the beach.
According to Kowalewski, humans can play a significant role in altering habitats through activities that many consider harmless, such as picking up and collecting seashells. “It is important that we continue to investigate the more subtle aspects of tourism-related activities and their impacts on coastal habitats.”
In the UK, the Coastal Protection Act of 1949 prohibits the removal of any natural materials from public beaches. In the US, collecting empty shells for recreational purposes is permitted in many cases. However, for some protected species, harvesting their live shells is illegal.
In 2018, a woman reportedly faced jail time after collecting 40 seashells from a beach in Key West, Florida. The shells contained live queen conchs, a species listed as threatened under the Endangered Species Act. The 30-year-old woman was sentenced to 15 days in jail and fined $500.
