Plata Canyon System is an important reproductive area for one shark species.

Captures of Blue Shark neonates, young-of-the-year (YOY), and small juveniles (age =<1 year) in the Atlantic Ocean are concentrated in this area (Coelho et al. 2018). An analysis of observer data from commercial, artisanal, and scientific longline fisheries across the Atlantic Ocean was conducted, including a variety of timeframes for the different datasets, such as 1998–2012 in the Uruguayan commercial longline fishery (Coelho et al. 2018). Early life stages were classified by size measurements, with neonate and YOY (age = 0) defined as <61 and <66 cm fork length (FL) for females and males, respectively, and young juveniles (age = 1 year) as <97.5 cm FL (Coelho et al. 2018). Early life stages were grouped because small Blue Sharks are thought to remain in nursery areas before migrating when they reach ~130 cm total length (TL) (Nakano & Stevens 2008). Although early life stages were also found in the southeast Atlantic Ocean and around a band spanning from the mainland of Portugal to the Azores, the main hotspot of captures was in this area, highlighting its importance as a reproductive area. While the spatial resolution of this analysis was coarse (Coelho et al. 2018), a more detailed dataset from another study (Domingo et al. 2008) was used to delineate the boundary. The latter study examined Blue Shark captures in the Brazilian and Uruguayan longline fishery between 1985–2007 and showed that captures of small individuals <120 cm TL were concentrated in this area extending from the shelf break into offshore waters (Domingo et al. 2008). The size-at-birth for the species is 56 cm TL with an initial grow rate of 33 cm, indicating that Blue Sharks <120 cm in TL are <2 years old (Lessa et al. 2004; Hsu et al. 2015). Larger numbers of these life stages were recorded between July–September (Domingo et al. 2008), suggesting a seasonal nature to reproduction in this area. The area also broadly overlaps with the grid cell that had the smallest mean size (~90 cm FL) for male Blue Sharks captured in the wider region between 1998–2019 (Mas et al. 2023), highlighting the importance of this area for the early life stages of the species.