Dolphins and sharks are by no means friends. In fact, after humans, sharks are probably the #1 killer of dolphins in the wild. But not all sharks are deadly – and some species of shark , like the cookie cutter shark, would prefer that their dolphin victims stay alive after an attack. The cookie cutter shark is a relatively small shark, and it makes its living by biting off small chunks of its victim’s flesh – usually in a circular pattern.
The ancestors of dolphins were four-legged land based animals who walked the earth many millions of years ago. Over the course of evolution, their bodies slowly adapted to life in the ocean, drastically altering their once familiar dog-like appearance.
There are many things that differentiate odontocetes or ‘toothed whales’ from mysticetes or ‘baleen whales. ’ The most obvious difference of course being that odontocetes have teeth and mysticetes have baleen. Coming in at a close second, however, is the fact that odontocetes echolocate while mysticetes do not. But, hold the boat folks: this fact may not be a fact after all. Just last year a team of scientists published an article in the Royal Society journal Biology Letters describing the first-ever recordings of something they termed “Megapclicks”: strange click sounds produced by humpback whales.
The Amazon river dolphin, otherwise known as the boto, is a freshwater river dolphin found in Southern America. The boto is often referred to as the ‘pink dolphin’, although not all individuals are pink. In fact, DCP learned this week at the Society for Marine Mammalogy’s Biennial conference that it is only the male botos that obtain a pink color, and that this is because of an accumulation of scar tissue. The boto’s natural color is a bluish gray. Male botos engage in aggressive biting matches, which scar their skin, causing bright pink patches to appear.
A whole list of factors will cause a dolphin to sink or swim in water, including how much air it has in its body, the amount of blubber it has, and perhaps most importantly, how deep it is in the water. Whether or not an animal floats or sinks in water is a direct result of something called buoyancy. The principle of buoyancy was initially discovered by the famous Greek mathematician Archimedes, who was born in 287 BC.
As you may know, dolphins are mammals . One of the defining characteristics of all mammal species is that they have hair on their bodies. But, what about dolphins? With their smooth streamlined shapes, it doesn’t look like they have any hair at all – do dolphins have hair? In fact, when dolphins are born, you can actually find a few stray hairs poking out of their chin.
What is spyhopping? In this week’s Dolphin Pod News, we heard a short audio clip wherein Hayden Panettiere mentions a cetacean behavior known as spy hopping . Describing her encounter with Japanese hunters and a group of pilot whales trapped in the cove, Hayden said: “There was one point when they were literally spy-hopping, which is when they jump out of the water and stick their heads up out of the water and they can look around”.
Surf’s up dude! Humans aren’t the only animal that likes to catch a wave every now and then. Even though they don’t use surf boards, dolphins love to go surfing! Just like human body surfers, dolphins have been known to ride the crests of big waves as they roll into shore. Just before the wave will crash into shore, the dolphins will turn around and rush back into open water. They can even be seen leaping clear out of the water from the top of a wave.