Skip to main content

Basking shark

Basking shark

The basking shark (Cetorhinus maximus) is the second-largest living shark and fish, after the whale shark, and one of three plankton-eating shark species, along with the whale shark and megamouth shark. Adults typically reach 7.9 m (26 ft) in length. It is usually greyish-brown, with mottled skin. The caudal fin has a strong lateral keel and a crescent shape. The basking shark is a cosmopolitan migratory species, found in all the world's temperate oceans. A slow-moving filter feeder, its common name derives from its habit of feeding at the surface, appearing to be basking in the warmer water there. It has anatomical adaptations for filter-feeding, such as a greatly enlarged mouth and highly developed gill rakers. Its snout is conical and the gill slits extend around the top and bottom of its head. The gill rakers, dark and bristle-like, are used to catch plankton as water filters through the mouth and over the gills. The teeth are numerous and very small, and often number 100 per row. The teeth have a single conical cusp, are curved backwards and are the same on both the upper and lower jaws. This species has the smallest weight-for-weight brain size of any shark, reflecting its relatively passive lifestyle. Basking sharks have been shown from satellite tracking to overwinter in both continental shelf (less than 200 m or 660 ft) and deeper waters. They may be found in either small shoals or alone. Despite their large size and threatening appearance, basking sharks are not aggressive and are harmless to humans. The basking shark has long been a commercially important fish as a source of food, shark fin, animal feed, and shark liver oil. Overexploitation has reduced its populations to the point where some have disappeared and others need protection.
 

Labels:

Comments

Post a Comment

Popular posts from this blog

Chilean Blob

Chilean Blob The Chilean Blob was a large mass of tissue found on Pinuno Beach in Los Muermos, Chile in July 2003. It weighed 13 tonnes (14 tons) and measured 12 metres (39 ft) across. The Chilean Blob made headlines around the world because biologists were initially unable to identify it, and were speculating that it was the remains of some species of giant octopus previously unknown to science. In June 2004, DNA found in the blob was found to match that of a sperm whale: the blob was a large mass of adipose tissue, the partial remains of a dead sperm whale.  
Post a Comment
Read more

Voynich Manuscript

Voynich Manuscript The Voynich manuscript is an illustrated codex hand-written in an otherwise unknown writing system, referred to as 'Voynichese'. The vellum on which it is written has been carbon-dated to the early 15th century (1404–1438), and stylistic analysis indicates it may have been composed in Italy during the Italian Renaissance. The origins, authorship, and purpose of the manuscript are debated. Various hypotheses have been suggested, including that it is an otherwise unrecorded script for a natural language or constructed language; an unread code, cypher, or other form of cryptography; or simply a meaningless hoax. The manuscript currently consists of around 240 pages, but there is evidence that additional pages are missing. Some pages are foldable sheets of varying size. Most of the pages have fantastical illustrations or diagrams, some crudely coloured, with sections of the manuscript showing people, fictitious plants, astrological symbols, etc. The text is writt...
Post a Comment
Read more

Plitvice Lakes National Park

Plitvice Lakes National Park Plitvice Lakes National Park (Croatian: Nacionalni park Plitvička jezera, colloquially Plitvice, pronounced is one of the oldest and largest national parks in Croatia. In 1979, Plitvice Lakes National Park was inscribed on the UNESCO World Heritage list, due to its outstanding and picturesque series of tufa lakes, caves, connected by waterfalls.The national park was founded in 1949 and is in the mountainous karst area of central Croatia, at the border to Bosnia and Herzegovina. The important north–south road that passes through the national park area connects the Croatian inland with the Adriatic coastal region. The protected area extends over 296.85 square kilometres (73,350 acres). About 90% of this area is part of Lika-Senj County, while the remaining 10% is part of Karlovac County. Each year, more than 1 million visitors are recorded. Entrance is subject to variable charges, up to 250 kuna or around €34 per adult per day in summer 2018.
Post a Comment
Read more