Silver cyprinid

What it is

This species is a small, silvery fish belonging to the danio family. Its body is flattened laterally and covered with large scales that shine with a pearlescent sheen. A distinctive yellow tail sets it apart visually. The lateral line sits below the body's midpoint. Adults rarely exceed nine centimetres in length. This fish lives exclusively in the fresh waters of East Africa, specifically within the drainage systems connected to Lake Victoria.

Where it lives

The fish inhabits Lake Victoria, which borders Uganda, Kenya, and Tanzania. It also occurs in Lake Kyoga and Lake Nabugabo in Uganda. Within these lakes, it occupies both shallow coastal zones and deeper offshore areas. While adults usually stay between zero and twenty metres deep, their young can be found much deeper. In Lake Kyoga, they avoid water-lily swamps but thrive in turbulent sections of the Victoria Nile.

How it lives

Adults remain near the bottom during daylight hours and swim toward the surface at night. Juveniles spend their early stages in shallow waters before moving away from the shore. They feed primarily on zooplankton and insects caught at the water's surface. Predators include various birds and catfish species like Schilbe mystus. The fish grows rapidly, reaching sexual maturity within sixteen to twenty-five months.

Breeding and life cycle

Spawning happens throughout the entire year, showing two main peaks in August and again in December or January. Mature females produce more than one thousand eggs. These eggs drift freely in the water as plankton. Spawning likely takes place in shallower inshore areas. The rapid growth rate allows the population to recover quickly after environmental changes or predation events.

Fish and people

Locals call this fish mukene, omena, or dagaa depending on the language. It is a crucial food source across eastern and southern Africa. Fishermen catch them using light attraction on moonless nights. After capture, women spread the fish on sand, rocks, or nets to dry in the sun. The dried product is packed into sacks and sold in major markets like Mwanza and Kisumu. It serves as human food or chicken feed.

Status and threats

This species remains abundant in Lake Victoria despite significant ecological shifts. The introduction of Nile perch and Nile tilapia reduced competition from other native fish. Consequently, the silver cyprinid has become one of the few native species to maintain high numbers. There are no immediate threats listed that endanger its survival. It continues to support local economies and food supplies effectively.

Relatives and look-alikes

It is the sole member of the genus Rastrineobola. Other fish in Lake Victoria include haplochromine cichlids, which have declined due to introduced predators. The Nile perch and Nile tilapia are closely linked to its current ecological niche. It shares habitat with various catfish and birds that prey upon it. No other species closely resembles its specific combination of traits.

Questions people ask about Silver cyprinid

Good reading and sources

• Silver cyprinid on WikipediaEncyclopedia
• More photos on Wikimedia CommonsPhotos
• Wikidata recordOpen data