You’ve probably seen Finding Nemo, right? It’s the touching story of a clownfish traveling a great distance to find his son, plus some Ellen DeGeneres schtick.
New research, however, shows that in real life its the baby clownfish that make even more perilous journeys than the one shown in the film, traveling hundreds of miles through the open ocean to find new homes.
Adult clownfish are about as far from adventurous as you get. They live out their lives crouching in host anemones that protect them from predators with their poisonous stings, which the clownfish are immune to.
But researcher Dr Steve Simpson, Senior Lecturer in Marine Biology and Global Change at the University of Exeter, and colleagues from the Australian Research Council Centre of Excellence for Coral Reef Studies (ARC COE CRS), Sultan Qaboos University (Oman) and the Centre National de la Recherche Scientifique (France) found that clownfish larvae migrate more than 400 kilometers (about 250 miles) between two coral reef systems off the coast of Oman.
“This is an epic journey for these tiny week-old fish. When they arrive at the reef, they are less than a centimeter long, and only a few days old, so to travel hundreds of kilometres they must be riding ocean currents to assist their migration,” said Simpson.
The team harmlessly caught and released more than 400 fish during the study. It used DNA testing to determine how the fish, which have unique genetic signatures based on which reef they came from despite being the same species, were moving between the two populations.
Most of the migrations were from north to south, which confirmed the tiny larvae are using currents to aid their voyages.
“We found that the pattern of migration corresponded to the dominant ocean currents in the region that are driven by the winter monsoon,” said co-author Michel Claereboudt from Sultan Qaboos University.
Understanding just how connected reef systems can be an important aid to protecting these fragile environments, Simpson said.
“Our ability to predict how far fish larvae disperse helps us to manage coral reef ecosystems. Understanding connectivity means we can protect populations that are most sensitive, harvest from populations that have a regular and consistent turn-over, and design coherent networks of marine protected areas,” he said.
[Source: University of Exeter]
Images from University of Exeter and Wikimedia Commons