A new study by an international team of marine biologists has shown that jellyfish have extraordinarily advanced orientation skills and abilities while swimming.
It has been commonly thought by the world scientists till now that these aquatic creatures would just allow themselves drift with ocean currents. But the new study has showed that they possess extremely advanced direction abilities such as sensing the currents and swim accordingly, i.e. with or against them whenever required.
According to the scientists, the study may also reveal more about the strange mechanism by which jellyfish form blooms, which include hundreds and millions of these marine creatures efficiently swimming in a particular area for months giving tough times to the fishermen and the beachgoers.
The study, however, failed to explain how the jellyfish sense ocean currents. Some of the researchers explained it may sense the currents by the shear of water on their bodies.
For the new study, the researchers’ team used GPS data loggers and tagged them with 18 barrel jellyfish in the Bay of Biscay, off the France coast. The loggers continuously monitored acceleration, body orientation and location of all the jellyfish.
Explaining the study technique, study co-author Prof Graeme Hays, of Australia-based Deakin University said the tags were attached to the jellyfish in a much easier way than attaching them to other aquatic animals.
“We loop a cable tie around the peduncle that joins the swimming bell to the trailing arms. It takes seconds, and the tag stays on indefinitely,” Hays said while explaining the study.
Floating GPS devices were also used in the study to measure the orientation of ocean current in the area. The loggers showed that jellyfish don’t remain passive when the ocean current drifts them. In spite of this, they actively swam against the currents to maintain their initial position within the bloom.
Using the gathered data on jellyfish and currents, the researchers created a computer model of a movement pattern of jellyfish bloom in the ocean.
Prof Hays said that the computer model helped them to learn that “active and directed swimming helps maintain blooms.” Jellyfish within a bloom do not allow themselves being dispersed or washed ashore by currents, as per the computer simulation.
The computer model couldn’t offer explanation for how jellyfish navigate.
The findings of the study were reported this week online in the journal Current Biology.