U all (in Italy's equivalent of florida sea park) seemed to know about whales, whale sharks, great whites and dolphins but none of u knew squat about the humble Cetorhinus maximus. Rather a shame since it was one of the few fish there (dolphins too) that are present and breeding in british terrotorial waters.
The following says it better than I ever could (basically i dont understand half the words...at one point reading it i though it was talking about the weather i got so lots)
The following says it better than I ever could (basically i dont understand half the words...at one point reading it i though it was talking about the weather i got so lots)
| QUOTE |
| Current status A very large, plankton-feeding pelagic shark, the basking shark is the largest fish in UK waters (ca. 10-11 m maximum length), and the second largest in the world. It occurs in temperate waters circumglobally (temperature range 8-14oC). In the UK, it has been mainly recorded in surface waters from April to September, when mostly immature females are seen. It is possibly migratory with seasonal population movements inshore to feed on high abundances of zooplankton near tidal fronts in coastal areas. Migrations may be age- and sex-segregated. In late summer, in the north-east Atlantic, basking sharks are thought to disperse offshore. The winter distribution and the location of pregnant females year-round remains unknown, but is thought to be in deep water. There has been considerable variation in the numbers of sightings reported this century and in numbers taken by north-east Atlantic fisheries which indicates longer-term, perhaps cyclical changes in summer distribution patterns. The basking shark is thought to be ovoviviparous, but the life-cycle is poorly known. The only litter recorded was of six young 1.5 to 1.7 m long, larger than any other known shark. Information on length at age (growth) for male and female basking sharks is not known precisely and estimates are based on few data from a Scottish fishery (93 individuals). These data suggest males mature between 4.5-6 m (estimated 12-16 years) and females at a length of 8-10 m (possibly 20 years). Estimates for gestation period are 1-3 years. Females may, like some other Lamniformes species, rest between pregnancies. Longevity is not known. Like other lamniform shark species, it is slow to reach maturity and apparently has a reproductive capacity that is relatively low even for an elasmobranch, making it potentially vulnerable to exploitation. The unexploited population increase may be some 2-10% per annum, calculated for other large, slow-growing sharks. Recovery after exploitation and other population fluctuations will therefore operate over a time-scale of decades. Although widely distributed in both hemispheres, basking sharks appear to be most regularly recorded in coastal areas of the UK with seasonally persistent tidal fronts (eg western Scotland, Clyde area, central Irish Sea and the western approaches to the English Channel). In these areas, during summer they are usually seen in relatively large numbers feeding at the surface. This basking behaviour enables sightings to be made. The absence of surface sightings has been equated with the absence of basking sharks. They may, however, be present, but feeding deeper in the water column. Although sightings have regularly been recorded in UK and Irish territorial waters, no reliable population estimates are available as it is difficult to relate surface sightings to actual population size. Detailed records are only available for a few areas. Available evidence over longer time periods suggests fluctuations in summer incursions and numbers of basking sharks are unpredictable. Sightings around the British Isles generally appear to fluctuate, although this probably reflects inter-annual variations in observer effort, weather and other factors determining the probability of sightings in addition to population trends themselves. It is not known if local or discrete stocks occur. The basking shark is protected under Schedule 5 of the Wildlife and Countryside Act 1981. They are also protected within the territorial waters of the Isle of Man and Guernsey, in the Mediterranean under the Bern Convention (with EU reservation) and Barcelona Convention (unratified), and in US Atlantic waters. Directed fisheries are prohibited in New Zealand, but by-catch is landed. The global status is assessed as Vulnerable (A1a,d, A2d) in the 1996 IUCN Red List. Current factors causing loss or decline Habitat constraints and food availability are likely to be important factors regulating distribution and population size. Recent studies in the English Channel show that they exhibit selective foraging behaviour on productive zooplankton patches along thermal fronts, track tidally-controlled movements of patches, and follow frontal boundaries as they move. These findings and the apparent unpredictability in surface sightings suggest basking sharks to be dependent on enhanced productivity found near transient oceanographic features. Consequently, population trends in the north-east Atlantic will be linked with broad-scale changes in secondary production and controlling factors (eg summer stratification, North Atlantic Oscillation (NAO)). Capture in directed and by-catch fisheries are a potential threat to populations, although few are now caught commercially. The Achill Island fishery (western Ireland) declined after only 10 years of peak catches. However, the decline in surfacing sharks was parallelled by a decline in zooplankton in the north-east Atlantic over the same 38 year period, emphasising the broad-scale importance of food availability controlling the numbers of sharks sighted at the surface and hence potentially available to harpoon fisheries. This species may spend at least 50% of its time in deep water beyond the scope of directed or intensive by-catch fisheries. Part of this time may be spent mating and giving birth. Future risk could possibly arise from a combination of coastal and deep-water fisheries. Liver oil was traditionally the main product derived from basking sharks, but prices are now very low. Today fins are valuable in the Far East, both at first sale and dried. Meat and cartilage are also utilised, but are less valuable. A directed fishery by a small Norwegian fleet, has an annual quota in EU waters of 100 tonnes of basking shark liver. In recent years, very little or none of the quota has been taken. Current action The recent listing on Schedule 5 of the UK Wildlife and Countryside Act 1981 makes the deliberate killing of basking sharks an offence. This extends the protection already provided around the Isle of Man and Guernsey. Ratification of the Barcelona Convention and removal of the EU reservation on the Bern Convention could improve the status of the population visiting UK waters, if the Mediterranean and Atlantic populations are not separate. |
U get these babies out by me at carrick island and while out fishing have seen them swim around the boat....scary monsters can capsize it!