Tree ring data taken from the timbers of a 19th century vessel found in Argentina indicate the ship was a whaler out of Rhode Island, last seen afloat over 150 years ago. The remains — exposed at low tide on a beach near Puerto Madryn, a city about 1,127 km south of Buenos Aires — appear to be that of the Dolphin, according to research newly published in Dendrochronologia.
“I cannot say with a hundred per cent certainty, but analysis of the tree rings indicates it is very likely that this is the ship,” said Ignacio Mundo, the study’s lead author and a dendrochronologist at IANIGLA-CONICET, an Argentinian lab, in a Columbia University Earth Institute release.
The ship was first discovered on shores of Puerto Madryn in 2004, and several years later the remains — the barest remnants of the ship’s ribs and some of its hull — were first excavated. Speculation that the ship was the Dolphin has been circulating for a decade, but the recent team thinks the tree ring data certifies it.
Tree rings are an incredibly useful tool for dating events, from volcanic eruptions to colonialism in North America. They encode climatological trends like droughts, and of course tell time, since a tree grows a ring for every year it’s lived.
A couple of wood samples were taken (a gentle way of saying they were removed by a chainsaw) from the wreck and cross-referenced with the North American Drought Atlas. The atlas contains tree ring samples from about 30,000 trees dating back over 2,000 years.
The comparison confirmed that the wreck’s ribs were made of white oak and its hull and wooden nails were made of yellow pine and black locust, respectively. All three types of tree grow in the eastern United States. Dating of the wood indicated that some of the trees first started growing in 1679, and the latest oaks were cut in 1849, a year before the Dolphin’s construction began.
“The archaeologists are more conservative — they prefer a slightly higher standard, and I don’t blame them,” said Mukund Rao, a dendrochronologist at Columbia University’s Lamont-Doherty Tree Ring Lab, in the university release. “It’s true we don’t have something like the ship’s bell. But for me, the story is there in the tree rings.”
The details seem to line up, but there is no smoking gun for the wreck’s identity. It was a different story for the discovery this year of the wrecked ship that carried the Shackleton expedition. In that case, the name Endurance is still clearly emblazoned on the stern, more than a century after the vessel sank to the bottom of the Weddell Sea.