Amazonian Butterflies Flock to Turtle Tears for Salt
Kristen M. Foster
Nature never fails to amaze. Currently attracting attention are butterflies of the Amazon that are sipping up the tears of Yellow-spotted Side-necked turtles (Podocnemis unifilus). Experts believe the attraction to the tears is to the salt contained therein. Sodium is a mineral that is hard to come by in the western Amazon, according to Phil Torres, affiliated with Rice University and the Tambopata Research Center, Peru.
Turtles ingest sodium through a primarily carnivorous diet, but the same is not true for herbivores, “They end up needing this extra mineral source,” says Torres in an interview with LiveScience. Butterflies have other sources of sodium they rely on as well: animal urine, puddles, sweaty clothes and people.
Torres says that the activity appears to have little impact on the turtles though it may increase the risk of attracting other predators or obstructing their vision of oncoming threats. Geoff Gallice, graduate student of entomology at the Florida Museum of Natural History, agrees, “the butterflies are taking so little… They simply uptake salt through a process similar to absorption by placing the proboscis on the salt-laden (tears) and passively feed.” In fact, the turtles seem loathe to budge from their sunny spots as the butterflies alight on their shells and noses.
Torres has also witnessed bees in the same activity, drinking turtle tears, though the turtles are not as tolerant of the bees (as shown in the video). Torres suspects it is the buzzing of the wings to which they object.
This phenomenon seems to be particular to the region, other researchers report to LiveScience that they have not observed the butterfly-turtle relationship in much of the Americas. The western Amazon lacks in sodium because it is over 1,000 miles from what would be the primary source of salt, the Atlantic Ocean, and the Andes Mountains restrict it from mineral particles that would be blown in by the wind.
The Tambopata Research Center is located in the remote reaches of the Amazon, only accessible by boat on the Tambopata River. The Tambopata National Reserve covers 700,000 hectares and is a headquarters for researching and exploring Amazonian nature, wildlife and habitats.[Image and Video via Jeff Cremer, Perunature.com]