Rufiji Delta is an important reproductive area for one ray species.

Fisher interviews conducted in 2014 along the coast of Tanzania revealed a higher number of reports of Largetooth Sawfish captured in the Rufiji Delta compared to other sites in the country (Braulik et al. 2020). In this area, records of this species are as recent as 2013, with 15 reports of Largetooth Sawfish catches between 1990–2013, including reports of individuals caught months before the date of the interviews. Importantly, this area was the only site where neonates were recorded. Two catches were reported in the past 10 years in Nyamisati and Kiomboni, one measuring ~50 cm total length (TL) and one rostrum (22.5 cm) which was estimated to be from an individual measuring 93 cm TL (based on Whitty et al. 2013). Based on the reported size-at-birth for the species (72–90 cm TL; Last et al. 2016), these individuals were neonates. There were three independent reports from fishers that small sawfish (< 1oo cm TL) were caught regularly in the shallow waters of smaller channels in the delta (Braulik et al. 2020). Brackish and freshwater mangrove environments are amongst the preferred habitat for neonates, while adults live in marine waters (Kyne et al. 2021), highlighting the Rufiji Delta as suitable nursery habitat for the species.

Despite the relatively low number of verified reports, the fact that this area sustains adult animals and neonates is particularly significant considering the local extinction of Largetooth Sawfish from much of the Western Indian Ocean (Espinoza et al. 2022). More recent reports of sawfishes are not available due to the lack of monitoring in the area after 2014.