Scientists have discovered an interesting thing regarding the Narwhals- the unicorns of the sea. According to them, the Narwhals get puzzled about how to react when subjected to human-induced stress. The study revealed that when these Arctic Narwhals are frightened, their hearts slow down, but at the same time they prefer to swim quickly to escape. But this action can cost them badly, as they try to flee from danger with a limited blood supply. After being released from the net, these narwhals swim rapidly and dive deep into the ocean to escape from danger but while doing this the blood flow to the brain gets restricted which can be dangerous for them, says the new study.
Lead researcher Terry Williams from the University of California, Santa Cruz said, ‘This is an unusual reaction to an unusual kind of threat, I don’t believe that this is the normal response when the animals are being pursued by a killer whale.” Normally what happens is when an animal is subjected to any stresses or gets attacked, it tries to escape run away from danger and at that time the blood flow to heart increases. But that is not the case with the Narwhals. The more these see unicorn swim hard to escape from danger the more their heart rate decreases.
For the study, Williams collaborated with Dr. Mads Peter Heide-Jorgensen, from the Greenland Institute of Natural Resources and both decided to fit a satellite tag and a heart monitor to the body of narwhals. The heart monitor can also measure the depth and acceleration of the dive. The researchers then worked with hunters to find out those the narwhals that were already entangled in nets. At first, they measured the heart rate of the sitting narwhals. They found out that it was 60 beats per minute, but when they freed the narwhals from the nets, these sea Unicorns began to swim rapidly and tried to get deep into the waters to escape from the danger quickly as possible.
“The very first heart rate measurement was – as you would imagine fairly high. But the moment those animals took off, their heart rate immediately plunged down to three or four heartbeats per minute – 15 to 20 seconds between each beat,” stated Williams. According to her, initially, she and her group though that narwhals were trying to freeze themselves and were waiting for the threat to pass. But when they released them from the nets, they saw that they were swimming as fast as they could ever do. So you have these two opposite things happening at exactly the same time, heart rate is really low, and that is superimposed on an exercise response. It was crazy,” revealed Williams. Normally Narwhals are not known to face much human disturbance. They prefer to remain hidden among arctic sea ice. But rapidly increasing shipping and oil exploration might soon make narwhals face humanly intervenes.
So, This latest discovery might help scientists get detailed information about why the heart rate decreases and oxygen supply gets reduced so much when narwhals try to escape from threat by swimming rapidly deep into the oceans. In this way, a lot of narwhals can be saved from potential human-induced threats.