Southern German Bight is an important reproductive area for one shark species.

Neonate and young-of-the-year (YOY) Tope are regularly found in this area. The data to support the importance of this area for reproduction originates from catch databases from commercial, recreational, and independent fisheries surveys (J Edwards et al. unpubl. data 2025), the International Council for the Exploration of the Sea trawl surveys (ICES 2025), local ecological knowledge (LEK) (Noorlander et al. 2018), and mark-and-recapture data (Thorburn et al. 2019).

First, catch databases (1902–2022) from commercial and recreational fisheries, as well as fisheries-independent surveys, were used to assess the presence of pupping grounds in Dutch coastal waters (J Edwards et al. unpubl. data 2025). Records include historical data from the early 1900s, incidental captures from various surveys using several different gear types (from 1971 onward), and recent reports from recreational fishers (2016–2022). Data collated include species, capture location, total length (TL), and the presence of umbilical scars. Databases did not always distinguish between males and females, and pregnancies were not recorded, therefore only a subset of records were utilised to assess reproductive activity. Based on size data, Tope in the area were classified into three age classes: (1) neonates and YOY, <45 cm TL; (2) juveniles, 45–130 cm TL; and (3) adults, >130 cm TL (J Edwards et al. unpubl. data 2025). Size-at-birth for this species is 30–40 cm TL (Ebert et al. 2021). In Dutch coastal waters, measured females (n = 92) ranged in size between 28–165 cm TL, of which 40% were neonates and YOYs (measuring 28–45 cm TL), 54% were juveniles, and 6% were adults (J Edwards et al. unpubl. data 2025).

Second, data from the ICES International Bottom Trawl Survey in the North Sea (NS-IBTS) between 2010–2024 were used to examine reproductive areas for the species in the southern North Sea (ICES 2025). These data grouped Tope as neonates (<41 cm TL), YOY (41–51 cm TL), or larger juveniles and adults (>51 cm TL) (Dureuil & Worm 2015). Data were available as catch-per-unit-effort (CPUE; individuals per hour). The NS-IBTS data showed that Tope are almost exclusively captured in the southern North Sea (south of 55°N), where the species was captured in 73 of 2,725 hauls (2.7%; ICES 2025) with a CPUE of 1–2 individuals. Neonates and YOYs were only captured in the eastern part of the southern North Sea, mostly within this area, while larger juveniles and adults were almost exclusively captured in the western part, outside this area. A total of 17 neonates and 11 YOY were captured in this area, with just four other neonates captured outside of the area during the survey. Neonates and YOY were recorded in nine of the 15 survey years. The catchability of the fast-swimming and benthopelagic Tope in IBTS bottom trawl gear is limited, resulting in low numbers overall. However, anglers around Helgoland Island, just east of this area, also catch adult Tope (M Schaber pers. obs. 2025), highlighting the presence of adults in the region presumably before or after giving birth. Large juveniles and adults were captured in January–February and July–August in the area, but neonates and YOYs were only captured in July–August (ICES 2025), supporting boreal summer seasonality in reproduction.

In addition to these databases, LEK from interviews with fishers in Dutch coastal waters stated that neonate and YOY Tope (estimated at <50 cm TL) are more common in summer months in the area, supporting the seasonality presented from the NS-IBTS data (Noorlander et al. 2018). The modelled distribution of immature Tope based on mark-and-recapture data and the IBTS datasets confirm that this area constitutes an important habitat for the smallest size classes of Tope (Thorburn et al. 2019).