Take only Photos, Leave only Footprints
Pop culture often caricatures environmentalists as finger-wagging scolds who are determined to suck all the fun out of life in order to save the planet. Never mind that the stereotype is often false – most greens like a good time as much as anyone else – the label has stuck. Now, a new bit of news is likely to fuel enviros’ buzzkill image.
In a recent study published in the journal PLOS ONE, researchers warn that the classic, seemingly harmless pastime of beachcombing and shell collecting could have serious ecological repercussions for marine environments.
The report focused on shells commonly found at Llarga Beach in the Spanish province of Catalonia, some 50 miles southwest of Barcelona. From 1978 to 1981, a research team surveyed seashells on the beach. Then the authors of the current study returned to that site between 2008 and 2010 to check for the most common bivalve species. In the intervening 30 years, the beach hadn’t experienced any major changes in development, commercial fishing, or waves, but the number of tourists to the area had nearly tripled. And the number of seashells was almost three times lower.
According to the study results, intensified shell collection may have resulted in “multiple, currently unquantifiable, habitat changes such as increased beach erosion, changes in calcium carbonate recycling, and declines in diversity and abundance of organisms, which are dependent on shell availability.”
Seashells fill a variety of ecological roles, some of which are not entirely understood. Mollusks, arthropods, algae, sponges, sea grasses, and fish use shells for food and shelter. Since the primary component in seashells is calcium carbonate, a tiring substance for organisms to make, removing calcium carbonate from the bio-nutrient cycle can upset the ecological balance. As shells are broken down over time and returned to the beach as sand, they help prevent beach erosion. Shells also provide building material for bird nests.
No one argues that an entire ecosystem is harmed when a few people remove a few shells. The problem has to do with the frequency of beachcombing as visitor numbers increase. Millions of tourists on beaches around the world collecting shells year after year adds up.
The researchers point out that much more remains to be learned about how shell removal impacts beach ecology: “The removal of dead shell remains by tourists represents one of the most understudied and least understood processes associated with human activities along marine shorelines.”
Until such questions have a definitive answer, it’s probably best to act with restraint, and remember the old backpacker’s motto: Take only photos, leave only footprints.
—EcoWatch 1/13; Science Daily 1/9