LAUSR

The broadnose sevengill shark, Notorynchus cepedianus (Péron, 1807), is a large marine top predator in temperate coastal ecosystems. Some aspects of its life history have been determined but its growth pattern is yet to be fully understood. We used a multi-modeling approach and a sensitivity test to estimate growth parameters from young-of-year (YOY) length data collected off San Antonio Cape (SAC), Argentina, a critical habitat in the Southwest Atlantic Coastal Zone (SACZ). The best selected model, a sex-combined logistic growth model, estimated an asymptotic length (L∞ ) of 92.58 cm TL (95% CI: 86.48 - 105.89 cm), a growth coefficient (K) of 0.006818 days -1 (95% CI: 0.004948 - 0.008777), and a size at birth (L0 ) of 40.73 cm. The predicted annual growth (i.e. L1 - L0 ) was 43.2 cm TL. Males had smaller Lo , higher K, and achieved larger sizes after one year. The YOY in SAC attained a larger L1 and grew faster than their Australian and South African wild counterparts. The consistent year-round presence of YOY in the SAC highlights the importance of this area as a pupping ground and potential nursery for N. cepedianus; this has direct implications for the allocation of research and management effort for the conservation of this species in the Southwest Atlantic. This article is protected by copyright. All rights reserved.