Updated distributions of the diatom Didymosphenia geminata (Lyngbye) Schmidt in Tierra del Fuego, Patagonia

GABRIELA GONZÁLEZ GARRAZA; PATRICIA RODRIGUEZ

DIATOM RESEARCH

BIOPRESS LIMITED

Lugar: Bristol; Año: 2022

0269-249X

In this study, we report new observations on the distribution of the invasive diatom Didymosphenia geminata in the island of Tierra del Fuego, southern Patagonia. We present new findings as well as data collected by the monitoring programme of the Government of the Tierra del Fuego. The first documented report of D. geminata in the island was in 2013, in the watershed of the Rio Grande, northeast of the island. In 2017, we found D. geminata in Lapataia River, within the Tierra del Fuego National Park. More recently, we detected the presence of D. geminata in two more points; one location in the Lake Fagnano, the largest lake in Tierra del Fuego (600 km2)situated in the centre of the island and the other location in the stream Arroyo Grande, near the city of Ushuaia . Hence, in eight years since its first record in Tierra del Fuego, this invasive diatom has spread and reached the southern part of the island despite prevention measures applied in protected areas since 2014(e.g., fishing was not allowed in the National Park and disinfection of fishing equipment was encouraged in other places) . Although D. geminata is already in Tierra de Fuego, the island in home to many water bodies with high conservation value. The monitoring of the range expansion of this invasive diatom should continue since prevention is the only one tool we have to prevent further expansion of D. geminata. Attention should be paid to these findings because Ushuaia, positioned in the southern part of the island, is a port from where many touristcompanies depart to Antarctica, a continent not yet impacted by D. geminata.