Sunday, October 20, 2019
Fascinating Facts About Arctic Bearded Seal
Fascinating Facts About Arctic Bearded Seal The bearded seal (Erignathus barbatus) gets its name from its thick, light-colored whiskers, which resemble a beard. These ice seals live in Arctic waters, often on or near floating ice. Bearded seals are 7-8 feet long and weigh 575-800 pounds. Females are larger than males. Bearded seals have a small head, short snout, and square flippers. Their large body has a dark gray or brown coat that may have dark spots or rings. These seals live on or under the ice. They may even sleep in the water, with their heads at the surface so that they can breathe. When under the ice, they breathe through breathing holes, which they may form by pushing their heads through thin ice. Unlike ringed seals, bearded seals dont seem to maintain their breathing holes for long periods. When bearded seals rest on the ice, they lay near the edge, facing down so that they can quickly escape a predator. Classification Kingdom: AnimaliaPhylum: ChordataClass: MammaliaOrder: CarnivoraFamily: PhocidaeGenus: ErignathusSpecies: Barbatus Habitat and Distribution Bearded seals live in cold, icy regions in the Arctic, Pacific, and Atlantic Oceans. They are solitary animals who haul out on ice floes. They may also be found under the ice, but need to come up to the surface and breathe through breathing holes. They live in areas where the water is less than 650 feet deep. Feeding Bearded seals eat fish (e.g., Arctic cod), cephalopods (octopus), and crustaceans (shrimp and crab), and clams. They hunt near the ocean bottom, using their whiskers (vibrissae) to help find food. Reproduction Female bearded seals are sexually mature at around 5 years, while males become sexually mature at 6-7 years. From March to June, males vocalize. When they vocalize, the males dive in a spiral underwater, releasing bubbles as they go, which creates a circle. They surface in the center of the circle. They make a variety of sounds - trills, ascents, sweeps, and moans. Individual males have unique vocalizations, and some males are very territorial, while others may roam. The sounds are thought to be used to advertise their fitness to potential mates and have only been heard during the breeding season. Mating occurs in spring. Females give birth to a pup about 4 feet long in length and 75 pounds in weight the following spring. The total gestation period is about 11 months. Pups are born with a soft fur called lanugo. This fur is grayish-brown and is shed after about a month. Pups nurse their mothers rich, fatty milk for about 2-4 weeks, and then must fend for themselves. The life span of bearded seals is thought to be about 25-30 years. Conservation and Predators Bearded seals are listed as least concern on the IUCN Red List. Natural predators of bearded seals include polar bears (their main natural predators), killer whales (orcas), walruses and Greenland sharks. Human-caused threats include hunting (by native hunters), pollution, oil exploration and (potentially) oil spills, increased human noise, coastal development, and climate change. These seals use the ice for breeding, molting, and resting, so they are a species thought to be very vulnerable to global warming. In December 2012, two population segments (the Beringia and Okhotsk population segments) were listed under the Endangered Species Act. NOAA said that the listing was due to the likelihood of a significant decrease in sea ice later this century. References and Further Reading Alaska Department of Fish and Game. Bearded Seal. Accessed January 31, 2013.ARKive. Bearded Seal. Accessed January 31, 2013.Berta, A.; Churchill, M. 2012. Erignathus barbatus (Erxleben, 1777). Accessed through: World Register of Marine Species, January 31, 2013.Discovery of Sound in the Sea. Bearded Seal. Accessed January 31, 2013.Kovacs, K. Lowry, L. (IUCN SSC Pinniped Specialist Group) 2008. Erignathus barbatus. In: IUCN 2012. IUCN Red List of Threatened Species. Version 2012.2. Accessed January 31, 2013.NOAA Fisheries: Office of Protected Resources. Bearded Seal Accessed January 31, 2013.