Thanks for advancements in tracking technologies, scientists have discovered an intriguing behavioural trait amongst some marine species: They sometimes swim in circles.
When studying the navigational abilities of sea turtles, Tomoko Narazaki, a marine researcher at the University of Tokyo, observed that the turtles in her study would swim in circles so constantly “just like a machine.”
Instead of wearing earplugs at a rock concert, imagine you could simply tune a dial inside your ears to lower the volume and protect your hearing. In a new report published in Integrative Zoology, researchers have discovered four whale species and dolphins can do just that. This could potentially shield the animals from navy sonar and oil drilling, linked to at least 500 marine mammal deaths since 1963.
If the hypothesis turns out to be true, it would represent the first evidence of such a trait in a marine mammal.
Randall Davis of the Department of Marine Biology at Texas A&M University, Terrie Williams, a professor of ecology and evolutionary biology at the University of California, Santa Cruz and another colleague, Lee Fuiman, associate director of the University of Texas' Marine Science Institute in Port Aransas, have been studying the behaviour of Weddell's for decades.
Coral reef fishes have a life cycle that is divided in two. They begin their life after hatching with a pelagic larval phase, lasting from a week up to two months depending on the species, and ends with a benthic phase, when the fish larvae settles to the coral reef one night. For decades the pelagic phase has been a black box to researchers. Only recently has the lid to this black box been opened.