Ben is convinced that seals can control the sensitivity of their whiskers. I'm pretty sure they must have the ability to tune their sensitivity. Mammals generally have regularly shaped, round whiskers. But nearly all seal species have whiskers that are irregular and wavy. The irregular shape of the whisker holds it steady as the seal swims. The whisker only vibrates in response to hydrodynamic trails.
The top whisker A belongs to a California sea lion, while the bottom wavy whisker B is from a harbour seal. Scientists' experiments have shown that seals are sensitive enough to detect fish m away. Researchers are continuing to investigate the seals' secrets, trying to understand how the seal converts whisker vibration into an understanding of where its target is located.
They hope they can use their discoveries to create improved artificial sensor systems for ships, submarines and underwater robots. Ben also thinks that the seals have more whisker tricks to uncover. I've seen the seals vibrate their whiskers, so perhaps they can send out signals and receive them. Get email updates about our news, science, exhibitions, events, products, services and fundraising activities. You must be over the age of Privacy notice.
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You don't have any saved articles. By James McNish. This species is highly migratory, with individuals following Arctic sea ice as it expands and contracts throughout the year. Harp seals are foraging predators that eat several dozen species of bony fishes and invertebrates. They will eat just about anything they can catch.
Juveniles eat krill and other pelagic crustaceans, and the diet diversifies as they grow. Adult harp seals are eaten by killer whales and large sharks. Juveniles are eaten by polar bears and other terrestrial predators, including foxes and wolves.
Courtship among harp seals takes place on the ice surface, but mating typically occurs in the water. Both males and females may mate with several partners during the mating season. Like all mammals, harp seals reproduce via internal fertilization and give birth to live young. Pups are born on the ice surface and are nursed by their mothers for only 12 days.
After the nursing period, the pup is still quite helpless and unable to hunt for several weeks. Harp seals grow up to 6 feet 1. Arctic seals, which spend time on ice, may sometimes eat fresh water ice and snow. Seals have many well developed whiskers, much like a cat. Like cats, they have a very acute sense of touch. Scientists think seals can use their whiskers to feel vibrations from swimming prey.
Blind seals in the wild seem to be able to hunt and feed without sight. Seals can hear very well both above and below water. They can hear high pitched sounds well above the range of human hearing. Seals see very well under water—better than they do in bright light above water. Their eyes are adapted with round lenses like fish and a large iris that fully opens underwater. On land the iris closes the pupil to a small pin point that lets the seal see clearly through the round lens.
Seals make many sounds both out of the water—like elephant seals, and under water—like harbor seals. Scientists have recently started to use the sounds harbor seals make during mating season to identify and track them. Seal mothers and pups as opposed to other pinnipeds generally stay close together on shore and are not separated while nursing.
Harbor seals are an exception, and mothers will leave pups on shore to feed offshore. Seal mothers and pups can stay in contact by sound. Harbor seal pups make distinctive calls that can be heard for up to a kilometer. When in close contact mothers and pups can identify each other by scent, recognizing scent from glands in the skin of their flippers and around their muzzles.
If you see a harbor seal pup on shore, observe it from a distance and do not approach—its mother may be offshore. Seal pups are naturally attracted to moving objects that are bigger than they are. Recent improvements in tracking technology satellite tracking, GPS tracking has shown that seals can travel great distances and return to the same spots on shore with great precision.
Grey seals can swim from Cape Cod to Nova Scotia in a matter of days. Seals, sea lions and walruses are currently placed in a sub-order, the Pinnipedia, of the Order Carnivora which includes bears, dogs, racoons, weasels, hyenas cats, and mongooses.
There are many recent studies on the genetic and fossil history of these groups and their place in the scheme of mammalian classification may well change in the near future.
Three families of living pinnipeds are recognized, the Phocidae hair seals or true seals , the Otaridae fur seals and sea lions and the Odobenidae walrus. The term pinnipedia translates from Latin as "fin foot". All of these animals must come ashore to breed, give birth and nurse their young.
Some species are at sea for several months at a time while others return to the shore every day. In addition, most seals are opportunistic feeders and will consume a variety of fish, shellfish, and crustaceans. Seals do not eat on land. It is absolutely normal for seals to be on land.
Seals are semi-aquatic, which means they often spend a portion of each day on land. Seals need to haul out for a variety of reasons: to rest, give birth, and molt annual shedding of old hair. Young seals may haul out on land for up to a week.
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