Down through the century’s seashell collecting has played an important role in our global culture. Explorers traveling to Africa found natives using shells being exchanged as money instead of gold and silver. Seashells have been used for basins, tubs, buckets, lamps and cutting tools by native people. More recently collecting shells has become a reminder of a beach vacation, or a hobby for people who collect them for their beauty. A study published on January 8 in the journal Plos One studied the effect of tourism on seashell loss.
You may wonder why the loss of seashells is of such concern. It is because they are an important part of our ecosystem. Michael Kowalewski, the lead author of the study and a curator at the Florida Museum of Natural History, explained that shells are used as building material for bird nests, attachment surface for diverse marine organisms, shelters for fish to hide from predators and used by hermit crabs as their protective armor. Removal of shells may alter the rate of shoreline erosion. Seashells, the exoskeletons of mollusks such as snails, clams, and oysters are also important because they are composed mostly of calcium carbonate and in many coastal habitats they dissolve and recycle back into the ocean.
The study conducted by researchers from the Florida Museum of Natural History and the University of Barcelona. The study was done on Llarga Beach on the coast of Spain. Multiple surveys were done from 1978 to 1981 and from 2008 to 2010. Its results showed that increased tourism on the Mediterranean coast of Spain correlated with a 70 percent decrease in Mollusk shells during the tourist season in July and August and a 60 percent decrease in other months. There were no new commercial fisheries or urban development since the 1970’s nor changes in local environmental conditions.
Michael Kowalewski said “shell collecting by beachcombers is an intuitively obvious explanation, but many other processes with tourism can lead to removal or destruction of shells.” He named beach grooming with heavy machinery and the use of recreational vehicles on the sand. He said that further research is needed to see if the pattern holds up in other places.
