The bayad (''Bagrus bajad''), is a
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of
bagrid catfish
The Bagridae are a family of catfish that are native to Africa ('' Bagrus'') and Asia (all other genera) from Japan to Borneo. It includes about 245 species. These fish are commonly known as naked catfishes or bagrid catfishes.
Many large bagri ...
from Africa.
Distribution
The natural habitat of the bayad are lakes and rivers in Africa. These include lakes such as
Lake Chad
Lake Chad (french: Lac Tchad) is a historically large, shallow, endorheic lake in Central Africa, which has varied in size over the centuries. According to the ''Global Resource Information Database'' of the United Nations Environment Programme, ...
,
Lake Albert, and
Lake Turkana
Lake Turkana (), formerly known as Lake Rudolf, is a lake in the Kenyan Rift Valley, in northern Kenya, with its far northern end crossing into Ethiopia. It is the world's largest permanent desert lake and the world's largest alkaline lake. B ...
, as well as rivers such as the
Nile
The Nile, , Bohairic , lg, Kiira , Nobiin language, Nobiin: Áman Dawū is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The Nile is the longest river in Africa and has historically been considered ...
, the
Niger
)
, official_languages =
, languages_type = National languages[Senegal
Senegal,; Wolof: ''Senegaal''; Pulaar: 𞤅𞤫𞤲𞤫𞤺𞤢𞥄𞤤𞤭 (Senegaali); Arabic: السنغال ''As-Sinighal'') officially the Republic of Senegal,; Wolof: ''Réewum Senegaal''; Pulaar : 𞤈𞤫𞤲𞤣𞤢𞥄𞤲𞤣𞤭 ...](_blank)
.
Description
The bayad's body is generally elongated in shape. The dorsal fin has a smooth spine, and the pectoral fins have spines with serrations on the inside. There are four pairs of barbel anatomy barbels. The maxillary barbels usually reach to the ventral fin or pelvic fins. This fish is yellow-greenish or blackish with a white belly. The fins are darker, sometimes reddish purple. Juveniles have little black spots on the sides.
The bayad has a maximum size of about 112 centimetres (44.1 in)
FL. It has a maximum published weight of 12.5 kilograms (27.5 lb), but is reputed to reach 100 kg (220 lb). Mean sizes and weight of males are less than those of females from the same age. Males grow up to 7 years old, females 8 years (Ref. 51644).
[
]
Ecology
The bayad is found in lakes, swamps and rivers. It avoids salt water
Saline water (more commonly known as salt water) is water that contains a high concentration of dissolved salts (mainly sodium chloride). On the United States Geological Survey (USGS) salinity scale, saline water is saltier than brackish water, ...
. This species spends nearly the whole of the daylight hours in crevices of rocks and is therefore seldom seen. It lives and feeds on or near the bottom.[ Adults are exclusively ]piscivorous
A piscivore () is a carnivorous animal that eats primarily fish. The name ''piscivore'' is derived . Piscivore is equivalent to the Greek-derived word ichthyophage, both of which mean "fish eater". Fish were the diet of early tetrapod evoluti ...
; it preys on small fish, particularly ''Alestes
''Alestes'' is a genus in the family Alestidae, known as the "African Characidae" as they are found exclusively on that continent. As suggested by that name, they Alestidae was formerly included in Characidae. ''Myletes'' is a synonym of ''Ales ...
'' species, or ''Chrysichthys auratus
The Golden Nile Catfish, ''Chrysichthys auratus'' is a species of fish belonging to the family Claroteidae
The Claroteidae are a family of catfish (order Siluriformes) found in Africa. This family was separated from Bagridae. However, the mono ...
'' as in Lake Kainji
Kainji Lake, in North Central Nigeria, is a reservoir on the Niger River, formed by the Kainji Dam. It was formed in 1968 and is a part of Niger State and Kebbi State. Kainji Lake National Park (KNLP), situated around the lake, is Nigeria's oldes ...
. These fish also feed on insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...
s, crustacean
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group ...
s, mollusk
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...
s, and vegetable matter. The efficiency of catching prey catfish is maximised by face to face attack, avoiding damage by dorsal and pectoral spines of the prey.[
There is some indication that the species comes to shallower water to breed. ]Spawning
Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of releasing the eggs and sperm, and the act of both sexes is called spawning. Most aquatic animals, except for aquati ...
season extends from April to July. The parents build and guard the nest, which is like a flat disc with a central hole where the eggs are dropped; the size of the nest and the central hole depend on the fish size.
Relationship to humans
The bayad is an important food fish. The bayad flesh is good eating and is of economic importance, commonly sold as food.[
]
References
Images and details at Planetcatfish
{{Taxonbar, from=Q3768532
Bagrus
Fish of Lake Turkana
Freshwater fish of Kenya
Freshwater fish of West Africa
Fish of Cameroon
Fish of Chad
Fish of Egypt
Fish of Ethiopia
Fish of Sudan
Fish of Uganda
Catfish of Africa
Fish described in 1775
Taxonomy articles created by Polbot