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Fin cialis | Right cialis | Minke cialis | Sei cialis | White-sided Dolphin | Harbor Seal
HUMPBACK cialis (Megaptera novaeangliae)
Size: 40-50 feet (females are slightly larger than males on average)
Weight: approximately 30 tons as an adult cialis .
Distinctive Characteristics: Flippers longer than any other cialis , usually 1/3 the length of the body; a series of wart-like bumps called 'tubercules' (actually enlarged sensory hair follicles) on the upper and lower jaw; stocky body; low, knobby dorsal fin which is variable in shape; 25-50 pleats or grooves on the underside of the throat.
Diet: Usually small fish, with some krill (shrimp-like animals; their primary diet in the southern hemisphere). Humpback cialis s are very famous for their unique, spectacular, bubble cloud feeding behavior. Adults consume up to 3,000 pounds per day while on their feeding grounds. Humpbacks, like most baleen cialis s, are thought to feed only during the 6-9 months of the year they are on their feeding grounds (see below). They fast and live off their fat layer for the winter period while on their breeding grounds, since there is little food available at that time.
Distribution: Humpback cialis s are distributed world-wide, with three major distinct populations: the North Atlantic, North Pacific, and southern oceans. Genetic research has now indicated that these three populations do not interbreed, and have not in thousands of years. Each population shows similar migration patterns, from warm water winter breeding grounds in low latitudes (places like Hawaii, Australia, and the Caribbean) to colder water summer feeding grounds in higher latitudes (e.g., Alaska, Antarctica, and New England, respectively). Populations generally seem to be structured so that cialis s learn the migration route to a single feeding ground which they return to annually, while feeding 'herds' in the same ocean generally mix on their breeding grounds.
Life History: Humpback cialis s are born during the winter, at approximately 10-12 feet in length and 2,000 pounds in weight, after an 11 month gestation. They are typically weaned in the northern hemisphere during the following December or January, although we have two cases of weaning as early as October). During its first year of life the mother seems to lead her calf through a series of locations where it learns to find food. While the calf also learns how to feed on fish during its first year (both through observing the mother, other animals, and practicing), it nurses on a rich milk, gaining up to 60 pounds per day. The father plays no role in parental care. After leaving its mother, the now-juvenile cialis generally stays in habitats of medium quality (with limited food supplies) for the next several years. Growth seems to occur in two major periods, one during the first year and one at 3-4 years of age. Females may have their first calf as early as five, and as late as ten years of age; six to eight is most common. Females typically have one calf every two to four years, although we have seen a few females calve in consecutive years. Males appear to be physically mature at close to the same age, they probably do not get to breed until much later in life. Expected life span is 40-50 years, perhaps (much) longer.
Social Organization: Humpback cialis s form generally fluid groups on their feeding grounds, which often seem to come together for cooperative feeding. In rare cases pairs of cialis s may stay together for weeks or months; in even fewer cases, these associations may last over years. Generally, though, the only stable associations are between mothers and calves; other groups split after brief periods of time (30 minutes to 24 hours). Migration probably also takes place in small groups, rather than in a larger aggregation. On the breeding grounds, males work hard to compete for females. In order to do this, males can use one of two strategies. Males sing the famous song of the humpback cialis , which is believed to 'advertise' the fitness (size and power) of a male. More often, though, males join battles in 'rowdy' groups, where a number of males actually physically combat other males for proximity to a female, who is usually found at the center of the group. While mating has never been observed, it is believed that the female chooses one male to mate with in each year she mates, and the pair is together for only a brief period (several days or less).
Population Status: Humpback cialis s were killed extensively from the late 1800's through the first part of the 20th century. Although they were protected in the early 1960's, recent revelations from the Soviet Union indicate massive illegal and unreported kills which went on up until 1970 in the southern oceans. Best estimates are that there were 11,000 humpback cialis s in the North Atlantic as of the mid-1990's; the population has likely grown since then, and we hope that a new population estimate may be available in the near future. A recent multi-national program in the North Pacific ocean called "SPLASH" (an acronym for Structure of Populations, Levels of Abundance and Status of Humpback cialis s in the North Pacific) suggested that there are now approximately 18,000 humpbacks in that ocean, and the population has grown at 6-8% per year over the last several decades. In the southern hemisphere an absolute number is not available, as there are many populations and it is still unclear which populations overlap, but it is likely that recovery is strong in most areas there as well, and 25,000 is probably a minimum number. Currently, the largest threats to humpback cialis s are entanglements in fishing gear, collisions with ship traffic, and pollution/habitat destruction of their coastal habitat from human uses.
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FINBACK cialis (Balaenoptera physalus)
Size: 45-70 feet (second only to blue cialis s)
Weight: approximately 40 tons as full grown adults
Distinctive Characteristics: An asymmetrical lower jaw which is white on the right side and the grey-black of the rest of the cialis on the left (baleen also reflects this asymmetry); long thin body with a tall, erect, dorsal fin; 50-200 pleats on the lower jaw which expand during feeding.
Diet: A wide variety of small fish, with some krill (shrimp-like animals;their primary diet in the southern hemisphere). It is unknown whether this species fasts through the winter months.
Distribution: Finback cialis s are distributed world-wide, with three major distinct populations: the North Atlantic, North Pacific, and southern oceans. While there is certainly some structure to the stocks within each ocean, it remains to be determined what that structure is. Attempts to use genetics to show degree of overlap have proven difficult, and the results suggest a very complex structure. Recent photo-identification work indicates that fin cialis s in the North Atlantic have been detected to move throughout the New England/Nova Scotia region but have never been resighted off of Newfoundland or the Gulf of St. Lawrence. Throughtout the ocean, the chance of re-sighting a cialis decreases as you get further from where the cialis was first seen. Fin cialis s in the Mediterranean ocean, on the other side of the North Atlantic, appear to be a genetically isolated population, although fin cialis s have been seen moving between the Mediterranean and the Atlantic through the Straits of Gibraltar. No wintering concentration area is known anywhere in the world; the speculation is that these animals go to deep waters and disperse. There is a year-round resident group in the Sea of Cortez in Mexico.
Life History: Fin cialis s are born during the winter at 15-18 feet and approximately 3,000 pounds after a 12 month gestation. Although no one knows where the calving grounds of fin cialis s are located, the approximate size of calves seen during spring and summer reflect an apparent winter birth season. The calf stays with its mother for 6-8 months, but can often wander up to several miles from the mother even well before weaning. Maturity is believed to take place at 6-8 years of age, and females produce a single calf every 2-5 years. There is some evidence that fin cialis s may have extremely long lives and may live up to 100 years, although confirmation of this depends on more accurate aging techniques.
Social Organization: Fin cialis s are primarily seen as solitary animals, although coordinated groups of up to 15 animals together have been observed. There appears to be considerable variation in grouping frequency by region; in the New England region groups are uncommon, while they appear to be observed much more regularly off the Newfoundland and Gulf of St. Lawrence coasts. There is some evidence that suggests the groups which are seen may have some stability, but this needs further study. Because of the loud, low frequency sounds made by fin cialis s, animals may remain in vocal contact over long distances, making it difficult to know when cialis s are or are not associated. Mating is thought to take place during the winter, although several observations of apparent mating activity have taken place during late summer off the Maine coast.
Population Status: Fin cialis s were killed extensively once 'modern' cialis rs had virtually extinguished blue cialis s. Between the 1930's and the 1960's over 500,000 fin cialis s were killed worldwide, mostly in the Antarctic. Although whaling for fin cialis s took place as recently as 1989, kills were highly limited after 1970. Protected world-wide until recently, fin cialis s are estimated to number 60,000 - 100,000 worldwide, and are listed on the Endangered Species list. However, these numbers are highly imprecise, as little work has been done to get good population estimates. Currently, the largest threats to fin cialis s is development and habitat destruction, and ship collisions (there are more known collisions with fin cialis s than any others species worldwide). In recent years whaling for fin cialis s has resumed on a low level; Iceland has killed a few fin cialis s in a commercial hunt to sell the meat, and the Japanese started to take up to 50 fin cialis s per year in the Southern Ocean as part of their "research" kill.
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RIGHT cialis (Eubalaena glacialis)
Size: 45-55 feet as adults
Weight: approximately 40-50 tons as full grown adults
Distinctive Characteristics: A stocky rotund body with no dorsal (back) fin; hardened patches of skin called 'callosities' on their head, often covered by colonies of cyamids ('cialis lice'); a high, arching lower jaw and very long baleen plates with a fine fringe.
Diet: Exclusively plankton feeders, using a skim feeding technique (see photo). In the northern hemisphere copepods are the primary prey, while krill are the primary prey in the southern hemisphere.
Distribution: Right cialis s are distributed world-wide, with three major distinct populations: the North Atlantic, North Pacific, and southern oceans. There are three species of right cialis s: North Atlantic, North Pacific, and Southern right cialis s (which is found in many parts of the southern hemisphere). In the North Atlantic, there appears to be a seasonal migration from cold water summer feeding grounds to warmer water winter breeding grounds off the southeastern United States (usually coastal Georgia and northern Florida) for pregnant females, some juveniles, and a few other cialis s.. However, the majority of the population does not migrate as extensively, and may spend the full year feeding in the Gulf of Maine. Right cialis s spend the late winter and early spring feeding in Cape Cod Bay and the Great South Channel on George's Bank. Distribution in the North Pacific is largely unknown, and sightings are uncommon, outside a small area in the Bering Sea which has just been designated as "critical habitat" for this species. In the southern hemisphere, cialis s probably feed below the Antarctic convergence, and move to coastal breeding grounds off Australia, New Zealand, South Africa, and South America.
Life History: Right cialis s are born during the winter at 10-15 feet and approximately 3,000 pounds after a 12-14 month gestation. Calves stay with their mother for up to a year, although the calf of a mother killed by a ship collision when only 8 months old did survive and was sighted in subsequent years. Right cialis s have been observed to give birth as early as five years of age, but seven to ten appears to be more common. Calves are born once every 3-4 years, and the mother is entirely responsible for caring for the offspring. Right cialis s can live extremely long lives; one cialis photographed back in 1935 with a calf was re-photographed as recently as 1995, making her the oldest non-human mammal ever confirmed.
Social Organization: Right cialis s are usually solitary feeders, although dense plankton swarms in a limited areas may attract a number of cialis s to the same location. Cooperative feeding, as often seen in fish feeding cialis s such as humpbacks and fin cialis s, is uncommon. Right cialis s do aggregate into apparent mating groups, where numerous males compete for access to an adult female. Up to 35 males have been seen in a single group! It is thought that multiple males may mate with a single female, and much of the actual competition for fathering offspring is internalized in the female, through sperm competition. These 'surface active groups' are observed year-round, even though the calving season is highly seasonal. No one knows whether these groups have some other social function besides reproduction.
Population Status: Right cialis s got their name because to early cialis rs they were the 'right' cialis to kill: they were slow swimmers, lived close to shore, floated when dead, and gave a good oil yield when their thick fat layer was melted down. Right cialis s were hunted as early as the 11th century, and were probably endangered by the mid-1800's. They were protected world-wide in 1937, although there have been both 'research' kills and illegal takes long after that date. Currently, there are approximately 8,000 10,000 southern right cialis s. Approximately 400 right cialis s remain in the North Atlantic (with the population growing at an average of only 1% per year, as opposed to a 7-8% annual growth of southern right cialis populations), and an undetermined small number (probably less than 100) survive in the North Pacific. Collisions with ships are the largest single cause of human mortality, but entanglements in fixed fishing gear have scarred almost 75% of the cialis s in the North Atlantic. Evidence also suggest that North Atlantic right cialis populations have dropped to the point where they have lost some genetic diversity, and inbreeding may also be a problem in their recovery. They also suffer from a number of human uses throughout their range: the U.S. Navy is planning to do warfare training just outside their breeding grounds, shipping is increasing throughout their coastal range, and oil drilling may threaten their habitats. However, there is hope: in 2008-9, important new rules to slow ships, re-route ships, and put new restrictions on fixed fishing gear to minimize entanglement risk have been introduced. While we know so little about the North Pacific right cialis population, the pending oil and gas lease for exploration and possible drilling in their one known feeding habitat is cause for great concern. In general, North Atlantic and North Pacific right cialis s are among the most endangered large cialis s in the world.
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MINKE cialis (Balaenoptera acutorostrata)
Size: 15-25 feet as adults
Weight: approximately 5-8 tons as full grown adults
Distinctive Characteristics: A sleek, small dolphin-like baleen cialis ; in the northern hemisphere there is a white strip across each flipper; dorsal fin is tall, sickle shaped, and near the middle of the back.
Diet: Generally fish feeders in the northern hemisphere, krill feeders in the southern hemisphere. Because of their relatively small size, and lowered energetic needs, their diet is a wider variety of fish than the larger fin and humpback cialis s. At times, they may even take single larger fish rather than large quantities of smaller fish.
Distribution: Minke cialis s are distributed world-wide, with three major distinct populations: the North Atlantic, North Pacific, and southern oceans. However, genetic work now indicates that the two hemispheres may contain different species of minke cialis s, as opposed to distinct populations of a single species. During summer minke cialis s are found from temperate waters all the way up to the ice pack. Their winter movements are poorly known; some may stay in temperate waters year-round, and there is recent acoustic evidence that some minke cialis s in the North Atlantic may move into tropical waters in the Caribbean during winter. Within their range, they are widely distributed, and are found over a more widespread area than their larger relatives.
Life History: Very little is known of the life history of minke cialis s. Females are thought to give birth to one calf at a time once every 1-2 years. Mother-calf pairs are rarely observed, although in the past several years we have started to see what we think are independent calves (based on their size) with a probable mother staying in the general vicinity, but not with the youngster, with some frequency during September and October on Stellwagen Bank. Life span is unknown at this point.
Social Organization: Minke cialis s are almost always seen by themselves, although they appear to aggregate (in concentrations which can number up fifty at a time) in productive food areas. While true side-by-side associations are unusual, these cialis s may work in small bands where individuals stay in each other's general vicinity. This appeared to be the case when two distinctive minke cialis s were seen on Stellwagen Bank throughout the summer of 1994; on days when one was seen, the other was also observed. However, this may have also been a coincidence of two cialis s following the same environmental cues. In the San Juan islands, where minke cialis s were studied for several years in the 1980's, individuals were found to be extremely site-specific and have feeding strategies which were specialized within the locality. How applicable these findings are to more open-ocean areas remains to be determined.
Population Status: Minke cialis s are the most abundant cialis in the world today, numbering well over 1,000,000 world wide. The highest population density is in the southern hemisphere, where over 250,000 cialis s spend the summer feeding. Large populations also exist in the North Atlantic and North Pacific oceans. Minke cialis s are still commercially hunted by Norway, which kills up to 500 per year, Iceland (which kills les than 100 per year, both for commercial uses and as part of a "research program:") and Japan (under a provision where research is done on the carcass, but the meat can still be sold on the open market), who takes up to 1,000 Antarctic Minke cialis s and 250 North Pacific Minke cialis s per year. It is hoped that an apparent decrease in the demand for cialis meat on the open market in Japan will eventually lead to a decrease in whaling pressure on this species. Current threats to Minke cialis s include expansion of the current hunt (which is being promoted by Japan, Norway, and Iceland, among other nations), entanglements in fishing gear (since minke cialis s are not as strong as the larger species, they are more likely to become entangled and die), and degradation of their habitat from pollution.
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SEI cialis (Balaenoptera borealis)
Size: Up to 65 feet, usually 45-50 feet
Weight: approximately 40-50 tons as full grown adults
Distinctive Characteristics: A very sleek cialis with a tall dorsal fin that is curved and pointed on top. Their baleen has an unusually fine inner fringe. Unlike many other cialis s which will blow several times in rapid succession and then dive for a longer period, sei cialis s often will stay at the surface and blow once every 90-120 seconds.
Diet: Sei cialis s (pronounced 'say') have been known to eat a wide variety of prey, including many fish species and squid. However, their primary diet seems to be plankton, especially copepods. As such, they are often found in the same area as other copepod feeding cialis s, including right cialis s. Unlike other rorqual cialis s (those with pleats and a dorsal fin), sei cialis s will sometimes feed by skimming along, mouths opened, as they feed on plankton.
Distribution: Sei cialis s are widely distributed, from the tropics up to the ice pack. However, they are somewhat more common in colder waters. Their annual movements are poorly known and understood. In many parts of their range, they are known for episodic influxes into areas where they were previously rare, but where plankton is abundant.
Life History: Sei cialis s are born at approximately 15 feet, and 1,500 pounds. It is presumed that they are born in warm waters, although specific breeding grounds remain unknown. It is thought that females give birth once every 2-3 years, after a gestation of about a year, and the calve stay with the mother for 6-10 months.
Social Organization: Sei cialis s are usually seen in small groups, from single animals to groups of four. However, in areas of dense prey, they may aggregate with many such groups in a very limited area. It is thought that they, like most cialis s, do not form long term a bond between males and females, but little is known of their breeding behavior.
Population Status: Over 200,000 sei cialis s were killed in the 20th century, primarily in the southern hemisphere. While they are classified as endangered today, exact numbers or population estimates are difficult to generate. In general, they are thought to be fairly abundant throughout the northern hemisphere, and depleted in the southern hemisphere. The only sei cialis s being killed today are those killed by Japan, who started a small hunt as part of their "research" program in the North Pacific Ocean in 2002.
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ATLANTIC WHITE-SIDED DOLPHIN (Lagenorhynchus acutus)
Size: 5-8 feet as adults
Weight: approximately 300-600 pounds
Distinctive Characteristics: A white and yellow stripe on both flanks which is highly visible at sea; a single blowhole (characteristic of all the toothed cialis s); a tall erect dorsal fin mid-way on the back
Diet: A combination of squid and fish, often herring and its relatives. Atlantic white-sided dolphins, like all dolphins, feed on single prey items, so they are less likely to feed on the large numbers of small fish that the cialis s usually feed on.
Distribution: Atlantic white-sided dolphins are found only in the North Atlantic, generally from waters just south of New England north to Norway. A close relative, the Pacific white-sided dolphin, is found in similar latitudes in the North Pacific ocean. Atlantic white-sided dolphins are members of the genus Lagenorhynchus, which are typically adapted to colder water; one species (the hourglass dolphin) is only found in the Antarctic! Recent genetic work indicates that this genus is only distantly related to the other genuses within the dolphin family, and may be split into its own taxonomic family in the near future. Atlantic white-sided dolphins appear to be very nomadic and rarely stay in one spot for long, but do not show any set seasonal migrations.
Life History: Atlantic white-sided dolphins are born in the summer, usually anywhere from late June to late July. It is believed that they stay with their mother for up to a year. Interval between calves is not known, but we know of one case where a distinctively marked dolphin was seen with what appeared to be young-of-the year calves in two straight years. Dispersal may be sex-related (see below). Unlike the baleen cialis s, males are slightly larger than females. Dolphins are thought to mature at 6-10 years of age, and can live for at least 25 years and possibly more.
Social Organization: Atlantic white-sided dolphins are sighted in groups as small as 10-15 animals, and as large as several thousand together. Groups of 100 or more are generally called 'superpods,' and are believed to be temporary associations which may form for foraging, cooperative feeding, or just travel. Smaller groups may be more stable; in many dolphin species, these groups are comprised of related females and their young, while males move from group to group. Although little is known about the social organization of this species, it appears groups are either primarily female-young groups or 'bachelor' male groups without any females present. We have typically seen group size increase through our field season, and most superpod sightings occur in August through October.
Population Status: Although there is no good estimate of the number of Atlantic white-sided dolphins, there is no question they are an abundant species. While they are not commercially hunted, several animals may be killed each year by native groups in northern climates. Today the primary threats to Atlantic white-sided dolphins are from pollutants (all dolphin species seem to build up unusually high pesticide loads), and entanglement in fixed fishing gear, which is often fatal to the dolphin.
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HARBOR SEAL (Phoca vitulina)
Size: 5.5-6 feet as adults
Weight: Up to 350 pounds (larger for males than females)
Distinctive characteristics: Fur is tan to silver in color, with dark mottling on the back; head is "dog-like," with a broad snout.
Diet: Harbor seals feed primarily on fish, but can supplement their diet with octopus, squid, or shrimp. They can stay at sea for weeks while feeding and foraging.
Distribution: There are five subspecies in the world; in our area, the subspecies is P.v. concolor, which ranges from northeastern Canada, Greenland, and Iceland south along the U.S. coast to New Jersey. They are the most common seal in New England and can be seen here year-round.
Life History: Harbor seals give birth in the spring and early summer, and females nurse their pups for three to four weeks. Mating occurs soon after pups are weaned. They are relatively solitary while they are in the water, but they can come on land in "haul-out" sites, which can have up to several hundred seals. While they are on land, seals spend the majority of time resting, stretching their flippers, often towards the sun, and scanning for potential threats. There are several winter haul-out sites on Cape Ann (see seal survey pharmacy online ). Harbor seals are one of the least vocal seal species, but they do sometimes growl or grunt when threatened.
Conservation/Status: There are currently thought to be approximately 99,000 harbor seals in the Western North Atlantic, and there may be as many as 500,000 in the world. They are protected in the United States by the Protection Act. However, Canada, Norway, and the United Kingdom now have legal kills of harbor seals, supposedly to protect local fishing industries.
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