Abstract
Very little is known about the factors which can cause collapse of the major food of lesser flamingos (Phoeniconaias minor) in East Africa, the cyanobacterium phytoplankton Arthrospira spp. (usually A. fusiformis), although it is known that collapses frequently occur. One possibility is infection by virus - cyanophages. We examined water samples from Lake Bogoria and found many different viruses, which could be infectious. We studied the density of Arthrospira spp. over a two-year period and found a crash in July 2016 at the same time as the maximum density of Virus-Like Particles (VLP) in the lake water; we achieved break-up of laboratory cultures grown in July 2016 lake water. We were not able to identify the virus with genetic analysis, but this is the first time that population collapse through cyanophage infection has been indicated.