Ecological Risk Screening Summary - Lake Magadi Tilapia (Alcolapia grahami) - Uncertain Risk

Species that are considered uncertain risk need a more in-depth assessment beyond the Risk Summary to better define the species’ risk to U.S. environments.

Lake Magadi Tilapia (Alcolapia grahami) is a cichlid species that was endemic to Lake Magadi. It is the only fish species in Lake Magadi and can exist in the lake’s hot springs, which can reach 40°C (104°F). The history of invasiveness is not documented. Alcolapia grahami was introduced in two locations, Lake Nakuru, Kenya, and Lake Natron, Tanzania. The population in Lake Nakuru became established. Previously this lake did not contain any fish species. Changes in the biological community, including a recent decline in the flamingo population, were seen at this lake after introduction but could not be directly linked or separated from the presence of this fish. Climate match was low, 0.000. All States had low individual climate scores. The climate match results may not accurately reflect the climate requirements of this species due to its use of the hot springs around the edge of Lake Magadi. RAMP does not have the ability to address microclimates such as the hot springs. Certainty of assessment was low. The overall risk assessment category is uncertain.