Twig Catfish (Farlowella vittata) Eggs Laid and Hatched at Smithsonian's National Zoo

By Karin Korpowski

Washington, DC - One of the Smithsonian’s National Zoo’s best camouflaged creatures came out of its hiding place to spawn. In the early morning on Nov. 12, the Zoo’s Amazonia exhibit welcomed a group of twig catfish (Farlowella vittata) hatchlings. This is the third time this species has produced young at the Zoo.

About a week earlier, the female laid a single layer of 30 to 60 transparent eggs on the glass of the animals’ aquarium. The male then assumed all responsibility for guarding the eggs. By day three or four, the embryos within were visible and moving. Twig catfish typically develop within six to 12 days of laying, depending upon aquarium conditions. As the fry hatch, males continue to watch over and guard them. These young are difficult to raise because they need a constant supply of their food of choice—algae—in order to grow and mature. The fry join their parents and eight other adult catfish in the Zoo’s collection. Only the non-breeding adults are on public display at a tank in Amazonia’s field station exhibit.

Twig catfish are native to the Amazon, Orinoco and Paraná rivers of South America and typically camouflage themselves within dead leaves and stick debris. Scientists don’t know this fish’s current population in the wild because they are extremely difficult to spot. Their body shape and brown-beige color perfectly mimic twigs and sticks. They grow to be four to six inches long. In the wild, females lay their eggs on open vertical surfaces, such as rocks that are covered in algae and other plant matter.

Photo Credit: Mehgan Murphy, National Zoo.

To view Smithsonian’s National Zoo’s web page on Zoo and Aquarium Visitor, go to:  http://www.zandavisitor.com/forumtopicdetail-3223-Smithsonian's_National_Zoo