Occurrence of the green sawfish Pristis zijsron in the Sudanese Red Sea with observations on reproduction

Abstract

All sawfishes have undergone severe declines in numbers and ranges due to anthropogenic activities. Consequently, all species have been listed as Endangered or Critically Endangered by the IUCN. The aim of this study was to identify the species of sawfish that occur in the Sudanese Red Sea and to assess their current status. Encounter data from landing sites and markets (2000-2016) and bottom trawling along the southern coast (2015-2016) were compiled. In addition, data from rostra were obtained from private collections and museums (collected from 1969 to 2014). Only the green sawfish Pristis zijsron was identified based on 26 rostra of neonates, juveniles, and adults as well as 6 carcasses (1 juvenile, 5 adults). Based on necropsies of 5 adult females and 11 live neonates, parturition occurred from October to late April. The smallest female that had developing follicles was 350 cm total length (TL). The number of embryos per brood was 6; however, fishers reported broods of 2, 8, and 12. Size at birth ranged from 60 to 80 cm TL. Current nursery areas are Marsa Ashat, Marsa Trinkitat (Srinikitat), and Agig Bay along the southern coast, and Dungonab and Oseif bays along the northern coast. These areas should be targeted for protection (e.g. marine reserves, time-area closures) if conserving the remaining green sawfish in the region is a priority.