KALUGA
Also known as the river beluga, they are claimed to be the largest freshwater fish in the world, with a maximum size of at least 1,000 kg (2,205 lb) and 5.6 m (18.6 ft). Local fishermen have suggested that the kaluga can grow well up to 20 ft in length and can weigh around 1,500 kg. The kaluga is one of the biggest of the sturgeon family. Like the slightly larger beluga, it spends part of its life in salt water. Unlike the beluga, this fish has 5 major rows of dermal scutes, nail-like teeth in its jaws, and feeds on salmon and other fish in the Amur. They have gray-green to black backs with a yellowish green-white underbelly.
The kaluga has been hunted to near extinction for its valuable roe. Despite constant anti-poaching patrols, poachers still continue to catch the fish. Fishing for kaluga anywhere in the Amur River is an offense punishable by law. However, kalugas are known to have an aggressive nature, and instances of them toppling fishing boats and drowning fishermen have been reported, although no concrete evidence exists of them assaulting or hunting people.
WHALE SHARK The whale shark Rhincodon typus is a slow-moving filter feeding confirmed individual had a length of 12.65 m (41.50 ft) and a weight of approximately 21.5 metric tons (47,000 lb), and unconfirmed reports of considerably larger whale sharks exist. Claims of individuals over 14 m (46 ft) long and weighing at least 30 metric tons (66,000 lb) are not uncommon. The whale shark holds many records for sheer size in the animal kingdom, most notably being by far the largest living non mammalian vertebrate. It is the sole member of the genus Rhincodon and the family, Rhincodontidae called Rhiniodon and Rhinodontidae before 1984, which belongs to the subclass Elasmobranchii in the class Chondrichthyes. The species originated about 60 million years ago.
The whale shark is found in open waters of the tropical oceans and is rarely found in water below 71 °F (22 °C). Modeling suggests a lifespan of about 70 years but measurements have proven difficult. Whale sharks have very large mouths and are filter feeders, which is a feeding mode that occurs in only two other sharks, the megamouth shark and the basking shark. They feed mainly on plankton and are generally considered harmless to humans.
The species was distinguished in April 1828 after the harpooning of a 4.6-m-long specimen in Table Bay, South Africa. Andrew Smith, a military doctor associated with British troops stationed in Cape Town, described it the following year. The name "whale shark" comes from the fish's size, being as large as some species of whales and also that it is a filter feeder like baleen whales.
GOLD FISH
The goldfish Carassius auratus is a freshwater fish in the family Cyprinidae of order Cypriniformes. It was one of the earliest fish to be domesticated, and is one of the most commonly kept aquarium fish.
A relatively small member of the carp family which also includes the koi carp and the crucian carp, the goldfish is a domesticated version of a less-colourful carp Carassius auratus native to east Asia. It was first domesticated in China more than a thousand years ago, and several distinct breeds have since been developed. Goldfish breeds vary greatly in size, body shape, fin configuration and colouration various combinations of white, yellow, orange, red, brown, and black are known.
HISTORY
Starting in ancient China, various species of carp collectively known as Asian carp have been domesticated and reared as food fish for thousands of years. Some of these normally gray or silver species have a tendency to produce red, orange or yellow colour mutations; this was first recorded during the Jin dynasty (265–420).
The kaluga Huso dauricus is a large predatory sturgeon found in the Amur River basin.
