Mousetrap Workspaces Histriophoca fasciata

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1 Page 1 of 9 Histriophoca fasciata You are working on a revision of a species account that is already published on ADW. This means that our existing account is not adequate or accurate. You will be expected to write this account anew and you will receive sole authorship. You can review the existing ADW account and use the list of references as a starting point in your research, but you cannot cite the existing ADW account. When ADW staff edit your account, they will compare the two accounts and decide which of the two will be published on ADW. Thanks for helping us to improve site content! Class: Mammalia Geographic Range Ribbon seals (Histriophoca fasciata) are native to Arctic regions, occurring throughout icy waters of the Edit northern Pacific Ocean and southern Arctic Ocean. Three populations of ribbon seals currently exist: two in the Sea of Okhotsk and one in the Bering Sea. Berta, Sumich, and Kovacs, 2006; MacDonald and Cook, 2009; Macdonald, 2006 Ribbon seals most frequently inhabit the Bering Sea and the Sea of Okhotsk. Both are located near southern Russia, just north of Korea and Japan. The southern-most limit of the ribbon seal range extends as far south as the Aleutian Islands, a chain of volcanic islands located just west of the Alaska Peninsula. The northern-most portion of their range extends to the Chukchi Sea, between Alaska and Siberia. Ribbon seals have been reported as far west as the Beaufort Sea, just beyond the limits of Alaska. Solitary ribbon seals also have been observed along the coast of California. "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008; Burns, 1970; MacDonald and Cook, 2009; Macdonald, 2006 Little is known about the extent of ribbon seal migration. During the breeding season, ribbon seals sometimes migrate to southern portions of the Chukchi Sea. They also are seen frequently in northern portions of the Bering Sea. Biogeographic Regions: Arctic Ocean ( Native); Pacific Ocean ( Native). Burns, 1970; Macdonald, 2006 Other Geographic Terms: Holarctic. Habitat Histriophoca fasciata is an Arctic marine mammal that spends the majority of its life in cold waters, where Edit water temperature range from 0 C (32 F) to as low as -40 C (-40 F). Because surface ice is abundant throughout these regions, H. fasciata prefers deeper waters, where ice is less solid and occurs in smaller pieces rather than large, contiguous masses. Ribbon seals prefer these environments, where it is relatively easy to break holes in the ice to enter the water while also maintaining access to solid ground. "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008; Fedoseev, 2002; MacDonald and Cook, 2009; Macdonald, 2006; Mizuno et al., 2002; Simpkins et al., 2003

2 Page 2 of 9 Ribbon seals prefer to remain near food sources, rather than traveling long distances to locate prey. Areas with broken ice chunks support constantly circulating water, which helps to create a stable food source. Ribbon seals also can dive to depths of 600 m to obtain food. "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008; Fedoseev, 2002; MacDonald and Cook, 2009; Macdonald, 2006; Mizuno et al., 2002; Simpkins et al., 2003 Ribbon seals also are found in the Okhotsk Sea, a region that is typically 80 to 90% covered with ice. It is believed that ribbon seals use this area for breeding, creating colonies of nests in deeper portions of the ice. These nest colonies, called rookeries, help to reduce predation by larger marine mammals, as many lack the ability to pull themselves onto the thick ice. "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008; Fedoseev, 2002; MacDonald and Cook, 2009; Macdonald, 2006; Mizuno et al., 2002; Simpkins et al., 2003 Elevation: Depth: 600 m (min) These animals are found in the following types of habitat: Temperate; Polar; Saltwater or marine. Terrestrial Biomes: Icecap. Aquatic Biomes: Pelagic; Coastal. Other: Physical Description There are three families of pinnipeds: eared seals (Family Otariidae), walruses (Family Odobenidae), and true Edit seals (Family Phocidae). Ribbon seals are classified as true seals (Family Phocidae). These phocids differ from other seals in several respects. Most pronounced is the unique alignment of their hindflippers that makes it difficult for them to walk on land. In this group, the hindflippers protrude behind the body, making it difficult for them to bring their hind limb forward. Phocids also differ in their lack of external ears and presence of a dense layer of blubber, providing insulation in their icy water habitat. Fedoseev, 2002; Macdonald, 2006 The respiratory system of ribbon seals is also unique. Ribbon seals lack lobes in the lungs. These lobes, common in other species, create multiple lung sections divided by thin walls of tissue. Ribbon seals also have well-developed air sacs, believed to help with buoyancy and production of sounds. These air sacs do not form until maturation and are considerably smaller in females than in males. Fedoseev, 2002 The general body shape of ribbon seals is similar to that of other pinnipeds. Like other pinnipeds, H. fasciata has a cylindrical body and flippers, limbs modified for swimming. These flippers help to propel pinnipeds through the water. Pinnipeds also have long whiskers known as vibrissae, located to the side of nose and extending below the snout. Vibrissae are extremely sensitive to vibrations in the water and can be used to locate prey. Like other pinnipeds, ribbon seals also have auditory canals (ear canals). These consist of a tube running from the outer ear to the inner ear and result in well-developed hearing across a broad range of frequencies in water. It is believed that they use a system similar to echolocation for navigating through water and for catching prey. Ribbon seals

3 Page 3 of 9 also have well-developed auditory senses on land, although their hearing occurs across a narrower range of frequencies than in water. "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008; Fedoseev, 2002; Macdonald, 2006 Newly born ribbon seals are white. Body color changes gradually with maturity, with adult males becoming reddish-brown in color until they molt or shed. After molting, the male coat changes to black. Females are usually lighter in color than males. Ribbon seals are easily distinguished from other phocids by the unique white band markings that occur all over their bodies. Markings begin to appear as early as 12 weeks, although they usually are not distinct until after the seal molts. Each ribbon seal has four white bands, creating a pronounced black and white contrast. These bands occur as follows: one is located around the neck, one around each of the fore-flippers, and one around the lower back before the hind-flipper. The size and exact location of each band varies from seal to seal. These markings are usually better expressed in males than in females, due to the lighter body color of females. "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008; Fedoseev, 2002; Renouf, 1991; Roest, 1964 Generally, three developmental stages are recognized in ribbon seals. Newborns typically range in body length from 73 to 98 cm, with a weight of 6 to 10 kg. Juveniles have a body length of 128 to 134 cm, with a weight of 40 to 50 kg. At about 2 to 3 years old, ribbon seals are considered adults, with a body size of roughly 145 to 155 cm and weight of 55 to 70 kg. Over the next few years, ribbon seals continue to grow and can reach a maximum length of 165 to 175 cm and weight of 72 to 90 kg. This increase is due to continuing development and additional accumulation of blubber, as well as changes after reproduction. Fedoseev, 2002 Another distinguishing feature of ribbon seals is a higher percentage of body weight attributable to vital organ volume. Major organs contribute to body weight as follows: 22% liver, 17% lungs, 8% heart, 7% diaphragm, and 2.7% kidneys. This is believed to help increase their diving and swimming abilities. Mass: 6 to 90 kg Length: 73 to 175 cm Wingspan: Basal Metabolic Rate: Some key physical features: Endothermic; Bilateral symmetry. Sexual dimorphism: Male larger; Sexes colored or patterned differently; Male more colorful. Fedoseev, 2002 Reproduction: Mating Systems Ribbon seals typically mate in reproductive rookeries established deep in the ice. Like most true seals (Family Edit Phocidae), ribbon seals are polygynous, meaning that each male typically mates with multiple females. Male ribbon seals use their air sac for vocalizations or phonation during mating, both to attract mates and to establish or defend territories. Macdonald, 2006

4 Page 4 of 9 Mating systems: Polygynous. Reproduction: General Behavior Male ribbon seals reach reproductive maturity at approximately three to six years of age. Females typically Edit mature earlier, between two to five years of age. Like most other mammals, ribbon seals are viviparous and have internal fertilization. This species also has the ability to undergo delayed implantation for two to four months. This allows them to wait until sufficient ice is present for birthing. Breeding season usually begins in late May, with breeding centering around the annual breakup of ice each spring. Ribbon seals have four different reproductive ecotypes. Each ecotype is adapted to different environmental conditions and have somewhat different physiological and anatomical features. Ice is the predominant selective factor in determining reproductive ecotypes, particularly differences in the depth, shape, and quantity of snow on the ice. Differences in ice also affect the duration of pup rearing and the size of individual pups. Atkinson, 1997; Fedoseev, 2002; Macdonald, 2006 Female ribbon seals have a gestation period of about 11 months, after which they give birth to a single pup, usually in April. It is rare for females to give birth to two pups. When this occurs, one usually does not survive. Females give birth and raise pups on packed ice. Pups average 73 to 98 cm long and 6 to 10 kg in body weight. Females nurse pups for four to six weeks, after which pups are weaned. Lactation milk is rich in proteins and fats which helps to rapidly increase the weight of the pup. After weaning, adults are able to mate again the following year. Breeding interval: Ribbon seals breed once annually. Breeding season: Ribbon seals breed from May to June. Number of offspring: Approximately 1 (average) Gestation period: 10 to 11 months Birth Mass: 6 to 10 kg Time to weaning: Approximately 1 months (average) Time to independence: Age at sexual or reproductive maturity (female): 2 to 5 years Age at sexual or reproductive maturity (male): 3 to 6 years Fedoseev, 2002; Macdonald, 2006 Key reproductive features: Iteroparous; Seasonal breeding; Year-round breeding; Gonochoric/gonochoristic/dioecious (sexes separate); Sexual; Viviparous; Delayed implantation. Reproduction: Parental Investment Like most seals, H. fasciata provides extended paternal care, although males are rarely seen with females or Edit pups. Females expend considerable energy to parental care, particularly energy to feeding and defending pups from adult males and potential predators. During lactation, females undergo a short fasting period in which they

5 Page 5 of 9 do not leave their pup. After the nursing period, females help pups to become independent by teaching them to dive for food and move efficiently on the ice. Fedoseev, 2002; Macdonald, 2006 Parental investment: Altricial; Female parental care; Pre-hatching/birth (Provisioning: Female, Protecting: Female); Pre-weaning/fledging (Provisioning: Female, Protecting: Female); Pre-independence (Provisioning: Female, Protecting: Female); Extended period of juvenile learning. Lifespan/Longevity Ribbon seals typically live for 25 to 30 years in the wild. Ribbon seal age can be determined roughly by Edit examining the horn covers on the front claws and the layers found on the tip of the tusks. Little is known about the lifespan of ribbon seals in captivity. However, harbor seals (Phoca vitulina), a closely related species belonging to the same taxonomic family, reportedly live up to 47 years in captivity. Longest known lifespan in wild: Longest known lifespan in captivity: Expected lifespan in wild: 20 to 30 years Expected lifespan in captivity: Fedoseev, 2002; Weigl, 2005 Behavior Histriophoca fasciata is a diurnal species, meaning they are most active during the day. This species uses the Edit daytime to forage for food and to find and attract a mate (during the spring season). Histriophoca fasciata can be social, however, usually only with members of its own species. A majority of its life is spent in the water, in order to obtain food and migrate from areas of thick, dense ice patches to areas of light ice (such as traveling from the Okhotsk Sea to the southern area of the Chuckchi Sea). During the breeding season, there is complete interaction among ribbon seals of all sizes, ages, and sexes. Breeding and molting season overlap, both happening during the spring ice breakup. Adult seals come to the ice in order to breed while juveniles use the ice as a site for molting. "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008; Fedoseev, 2002; MacDonald and Cook, 2009; Macdonald, 2006 Histriophoca fasciata behaves differently than other pinnipeds (including northern pinnipeds). Mothers leave their pups alone for extended periods of time, unlike most pinnipeds. A probable reason for this behavior is a lack of predation. Histriophoca fasciata is believed to experience less predation than other pinnipeds, most likely due to the breeding and rearing of pups on thinning ice, which creates a barrier for many sea predators. Also, ribbon seals lack a fear of humans, as they have historically had limited interactions. "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008; Fedoseev, 2002; MacDonald and Cook, 2009; Macdonald, 2006 Histriophoca fasciata demonstrates some unusual behaviors while on the ice. When they feel there may be a threat, they scan the area visually for a much longer period than other pinnipeds. Poor eyesight out of water is believed to be the reason for this extended scanning. When on the ice, they use their fore-flippers to dig in and propel them forward, moving in a serpentine motion. This also differs from most pinnipeds. Ribbon seals also

6 Page 6 of 9 display different behaviors when captured on ice than other pinnipeds. Unlike other species, they typically struggle less and often "play dead" until they are released. Home Range "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008; Macdonald, 2006 Ribbon seals are primarily found in the Bering Sea. They are primarily pelagic, so there is little known about the home range of an individual seal. Territory Size: Key behaviors: natatorial; diurnal; motile; migratory; social. Communication and Perception Only two types of sounds have been recorded for ribbon seals. These two sounds are believed to be used for Edit communication with other ribbon seals, but there have been no studies to date to confirm this. Other pinnipeds make sounds to communicate during hunting or mating, suggesting that ribbon seals may show similar modes of communication. "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008; Richardson et al., 1995; Watkins and Ray, 1977 It is believed that ribbon seals have poor vision on land, because of their reactions to potential threats. They look for danger, but they scan the land area for much longer periods of time than other pinnipeds. Ribbon seals also allow human approach much more so than other pinnipeds, possibly due to poor eyesight on land, as well as limited human interactions. They are believed to have well-developed vision in water, especially in deep water, where they hunt for most of their food. Little research has been conducted on hearing in ribbon seals, but other pinnipeds have poor hearing in water because they are well adapted to spending large amounts of time on land. The water slows down sound waves, making their hearing poor. "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008; Burns, 1970; Richardson et al., 1995; Watkins and Ray, 1977 Communicates with: acoustic. Other communication keywords: Perception channels: visual; tactile; acoustic; echolocation; chemical. Food Habits Ribbon seal food habits vary depending on their age, the time of year, and their location. The stomach content Edit of ribbon seals has been found to be different during the spring months, when ribbon seals begin whelping. Females undergo a brief fasting during whelping and lactation, in order to provide nutrition and protection to the pup. The diet of ribbon seals also changes from pup to adult. Around one to two years of age, juveniles feed primarily on shrimp. Adults have a less selective diet, eating different types of cephalopods, crustaceans, and fish. Their diet consists mainly of walleye pollock (Theragra chalcogramma) and magistrate armhook squid (Berryteuthis magister). On average, ribbon seals consume around 17 pounds of food per day.

7 Page 7 of 9 "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008; Dehn et al., 2007; Fedoseev, 2002; Macdonald, 2006 Carnivore: Piscivore; Eats non-insect arthropods; Molluscivore. Other Diet Features: Animal Foods: Fish; Mollusks; Aquatic Crustaceans. Plant Foods: Other Foods: Foraging Behaviors: Predation The only confirmed predator of ribbon seals is humans (Homo sapiens). From 1956 to 1992, hunting of several Edit species of seals that lived on ice was a very popular sport. This drastically decreased population sizes of ribbon seals. Once limitations were placed on hunting, ribbon seal populations increased. Humans still hunt ribbon seals, but it is not as common as it once was. "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008; Burns, 1970; MacDonald and Cook, 2009; Macdonald, 2006 It is likely that polar bears (Ursus maritimus), walruses (Odobenus rosmarus), killer whales (Orcinus orca), and pacific sleeper sharks (Somniosus pacificus) also prey on ribbon seals. Ribbon seals have been found in their stomach contents. These predators have been witnessed feeding on ribbon seals, but since they were not seen killing or hunting ribbon seals, it is not clear whether they are predators or just opportunists. Polar bears and killer whales are the most likely predators of ribbon seals. Both share the same habitat as ribbon seals and are known to eat other seals. Killer whales are most likely the major predator because they are found throughout the entire ribbon seal range. The range of polar bears typically does not extend further south than St. Matthew Island, so they are less likely to prey on ribbon seals, especially during the spring months when the ribbon seals migrate south. It is clear, however, that ribbon seals are not the primary prey of either of these animals. Known predators: "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008; Burns, 1970; MacDonald and Cook, 2009; Macdonald, 2006 Humans (Homo sapiens) Anti-predator adaptations:: Ecosystem Roles Histriophoca fasciata serves as potential prey for some species such as polar bears and killer whales. Other species may use the abandoned ice rookeries of H. fasciata as shelter or for breeding. Edit Key ways these animals impact their ecosystem: Creates habitat. "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008; MacDonald and Cook, 2009 Species (or larger taxonomic groups) used as hosts by this species:

8 Page 8 of 9... Species (or larger taxonomic groups) that are mutualists with this species:... Commensal or parasitic species (or larger taxonomic groups) that use this species as a host:... Economic Importance for Humans: Positive Ribbon seals do not provide known sources of economic benefit to humans, although sport hunting was common in the past. Edit Ways that people benefit from these animals: Economic Importance for Humans: Negative There are no known adverse effects of Histriophoca fasciata on humans. Edit Ways that these animals might be a problem for humans: Conservation Status There is little data on the current conservation status of H. fasciata. According to the IUCN Redlist, the most Edit recent population study was conducted in the 1970s. At that time, research suggested that H. fasciata populations were declining. A 1979 study estimated the population size of H. fasciata as 450,000 to 500,000 individuals. Since that time, Russia has mostly stopped large scale commercial hunting of H. fasciata and, in the United States, they are protected by the Marine Mammal Protection Act. These legislative acts were enacted after the last population study, so it is generally believed that population sizes should have increased. Due to the lack of current data, the IUCN Red List notes the current conservation status of H. fasciata as "Data Deficient". IUCN Red List: Data Deficient. US Federal List: No special status. CITES: No special status. State of Michigan List: No special status.

9 E2FB 4D2B A172 A77B34C30459/accou... Page 1 of 2 References Add Reference Choose a reference format National Oceanic and Atmospheric Administration. Status Review of the Ribbon Seal (Histriophoca fasciata). NMFS-AFSC-191. The Northwest Fisheries Science Center: U.S. Department of Commerce Abbrev: "Status Review of the Ribbon Seal ( Histriophoca fasciata )", 2008 Status: ok Delete Edit Atkinson, S Reproductive biology of seals. Reviews of Reproduction, 2: Abbrev: Atkinson, 1997 Status: ok Delete Edit Berta, A., J. Sumich, K. Kovacs Marine Mammals Evolutionary Biology. San Diego, California: Academic Press. Abbrev: Berta, Sumich and Kovacs, 2006 Status: ok Delete Edit Burns, J Remarks on the distribution and natural history oh phagophilic pinnipeds in the Bering and Chuckchi seas. Journal of Mammology, 51/3: Abbrev: Burns, 1970 Status: ok Delete Edit Dehn, L., G. Sheffield, E. Follmann, L. Duffy, D. Thomas, T. O'Hara Feeding ecology of phocid seals and some walrus in the Alaskan and Canadian Arctic as deteremined by stomach contents and stable isotope analysis. Polar Biology, 30/2: Abbrev: Dehn et al., 2007 Status: ok Delete Edit Fedoseev, G Ribbon seal (Histriophoca fasciata). Pp in W. Perrin, B. Wursig, J. G. M. Thewissen, eds. Encyclopedia of Marine Mammals, Vol. 1, 1 Edition. San Diego, CA: Academic Press. Abbrev: Fedoseev, 2002 Status: ok Delete Edit MacDonald, S., J. Cook Recent Mammals of Alaska. Fairfield, AK: University of Alaska Press. Abbrev: MacDonald and Cook, 2009 Status: ok Delete Edit Macdonald, D Seals, sea lions, and walruses. Pp in D. Macdonald, ed. The Princeton Encyclopedia of Mammals, Vol. 1, 1 Edition. Princeton, NJ: Princeton University Press. Abbrev: Macdonald, 2006 Status: ok Delete Edit Mizuno, A., A. Wada, T. Ishinazaka, K. Hattori, Y. Watanabe, N. Ohtaishi Distribution and abundance of spotted seals Phoca largha and ribbon seals Phoca fasciata in the southern Sea of Okhotsk. Ecological Research, 17: Abbrev: Mizuno et al., 2002 Status: ok Delete Edit Renouf, D Behaviour of Pinnipeds. University Press, Cambridge: Chapman and Hall. Abbrev: Renouf, 1991 Status: ok Delete Edit

10 E2FB 4D2B A172 A77B34C30459/accou... Page 2 of 2 Richardson, J., C. Greene, C. Malme, D. Thomson Marine Mammals and Noise. San Diego, California: Academic Press. Abbrev: Richardson et al., 1995 Status: ok Delete Edit Roest, A A ribbon seal from California. Journal of Mammalogy, 45/3: Abbrev: Roest, 1964 Status: ok Delete Edit Simpkins, M., L. Hiruki-Raring, G. Sheffield, J. Grebmeier, J. Bengtson Habitat selection by iceassociated pinnipeds near St. Lawrence Island, Alaska in March Polar Biology, 26/9: Abbrev: Simpkins et al., 2003 Status: ok Delete Edit Watkins, W., G. Ray Underwater sounds from ribbon seal, Phoco (Histriophoca) fasciata. Fishery Bulletin, 75/2: Abbrev: Watkins and Ray, 1977 Status: ok Delete Edit Weigl, R Longevity of mammals in captivity. Stuttgart: Kleine Senckenberg-Reihe 48. Abbrev: Weigl, 2005 Status: ok Delete Edit Discuss Taxon Account : 0 responses.