Elise Courtois looks like a ninja, standing on a rock in her hooded wetsuit. Then, the 41-year-old leaps down the 9-metre-high waterfall with all the elegance of a cat. Courtois says she loves her work that entails being outdoors, climbing, swimming, sliding and jumping every day. She is taking a team down the Polischellu gorge and all are revelling in the sparkling turquoise pools lined with ferns and boulders. Above and beside them are towering rocks and a forest that looks subtropical. Courtois comes from near Chamonix in the French Alps. She has spent 12 years as a canyoning guide on Réuni…