Te Whaka ā Te Wera/Paterson Inlet is an important area for undefined aggregations of one shark species.

Broadnose Sevengill Sharks aggregate in Te Whaka ā Te Wera/Paterson Inlet during summer (Housiaux et al. 2019; Lewis et al 2020, 2023). Between July 2013–May 2015, 45 boat surveys using chum were conducted in shallow areas (3–6 m depths) around Southwest Arm and Sawdust Bay to confirm anecdotal reports of Broadnose Sevengill Shark aggregations in this area (Housiaux et al. 2019). Animals measuring between 150–280 cm total length (TL) were recorded year-round in the area (Housiaux et al. 2019). This species was most frequently observed during spring and autumn (71–79% of surveys; mean = 3–3.3 sharks per survey), in comparison to winter (33% of surveys; mean = 2.9 sharks per survey; Housiaux et al. 2019). The surveys were also conducted in adjacent bays where Broadnose Sevengill Sharks were not observed. It is suspected that the sharks move south to Stewart Island in winter (B Finucci & CAJ Duffy pers. obs. 2024.).

Additionally, baited remote underwater video station (BRUVS) surveys (n = 133 deployments on 46 sampling days; mean = 22.2 deployments per season) were conducted in Sawdust Bay between June 2016–November 2017.  BRUVS were deployed for 60 minutes and were set ~2m from the seabed. Broadnose Sevengill Sharks (n = 357 encounters) were recorded in all but one deployment with 149 individually identified sharks and 17 individuals encountered multiple times (Lewis et al. 2020). Up to nine individuals were encountered per deployment (mean = 2.7). A larger number of sharks was observed in summer (mean = 4.30 encounters per deployment) compared to winter (mean = 1.34 encounters per deployment). Abundance estimates at Sawdust Bay were reported to be higher in spring and summer (84–93 individuals) than autumn and winter (35–43 individuals) (Lewis et al. 2020). Te Whaka ā Te Wera/Paterson Inlet is one of the few locations around New Zealand where this species regularly aggregates.

Observed sharks were estimated to measure 149–276 cm TL and there was a biased sex ratio, with females representing 95% and 73% of all sharks observed in winter and summer, respectively (Lewis et al. 2023). More females (63%) were estimated to be mature based on size, while males were equally estimated to be juvenile and mature (Lewis et al. 2023). This sexual bias for Broadnose Sevengill Sharks has been reported in other locations (e.g., in Argentina and Tasmania) during the same seasons as in Te Whaka ā Te Wera/Paterson Inlet (Lucifora et al. 2005; Barnett et al. 2010b). Broadnose Sevengill Sharks seasonally aggregate during summer in bays in other parts of the world for feeding or reproductive purposed (Ebert 1989; Lucifora et al. 2005; Barnett et al. 2010b; Abrantes & Barnett 2011; Williams et al. 2012; Stehfest et al. 2014; Hammerschlag et al. 2019). The nature and function of Broadnose Sevengill Shark aggregations in this area could be for feeding purposes. This is because their presence may be driven by a high abundance of potential demersal shark prey (e.g., Spiny Dogfish Squalus acanthias and Rig Mustelus lenticulatus) in the area (Lewis et al. 2020) as sharks and rays have been reported as important prey for the species in other locations (Ebert 1991, 2002; Barnett et al. 2010a). Further information is required to determine the nature and function of these aggregations.