Semesi's teaching career began in 1975 as
teaching assistant, rising to professor by the time of her death. Nicknamed ("mama mangroves" in Swahili), she specialised in mangrove ecology, and a member of the board of trustees for the
Western Indian Ocean Marine Science Association. These included a Fulbright Scholarship to the
University of South Florida in 1982, where she undertook a research project entitled "Analysis of Certain Marine
Phycocolloids". She was the recipient in 1992 of a
Pew Trust Fellowship, which she used to undertake a major study on the
Bagamoyo area, incorporating marine sources, socio-economic statistics and other factors. She died on 6 February 2001. Her death was described in
Pwani Yetu: The Newsletter of the Tanzania Coastal Management Partnership as a "great misfortune for marine conservation". == Recognition ==