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In the southern hemisphere, three nurseries areas have been reported from Australian and South African waters 10, 11. In Europe, the areas around the Sicilian Channel and the Aegean Sea are reported as zones with high abundances of juveniles 8, 9. In addition, Bahia Sebastian Vizcaino (off central Baja California) has recently been identified as another important GWS nursery area 7. For instance, in North America two large nursery area extends from the Southern California Bight (Point Conception to San Diego) to the Baja California Peninsula and from the New York-New Jersey Bight 3, 4, 5, 6. However, several nurseries have been proposed from different regions around the world. Current knowledge on GWS nursery areas is limited. Despite its importance as apex predator for the stability of marine ecosystems, the GWS is currently considered vulnerable to extinction due to increased pressure in fisheries 36. Young-of-the-year (YOY 175–300 cm) generally feed on teleost fishes, invertebrates and others sharks, whereas subadults and adults (>300 cm) commonly feed on aquatic mammals 35. The GWS is a generalist feeder with increasing trophic levels through ontogeny 34. Its presence along south-eastern Pacific coasts is uncommon 29, 30, 31, 32, 33. This species has been documented in aggregations around rocky reefs near pinniped colonies in northern California, eastern Australia, Canada and South Africa 26, 27, 28.

Its vertical distribution typically ranges from 0 to 250 m, but can extend down to 1200 m in some cases 25. It is also a highly migratory species that inhabits a wide range of marine environments, from very shallow waters of the continental shelf to oceanic waters and around remote islands, tolerating temperatures from 5° to 25 ☌ 24. The great white shark (herein, GWS) is a large, cosmopolitan, top predator 22 and comprises six genetically distinct population from Australia/New Zealand, South Africa, Mediterranean, North West Atlantic, North East Pacific, and Japan 23.

As such, the identification of nursery areas has significantly increased in recent years in an effort to mitigate of declines in shark numbers resulting from various anthropogenic activities and their impacts 1. Additionally, these areas also limit the access of larger sharks and therefore decreasing the predation risk 2. These have large and long-lasting effects on population size, secure the survival of shark species and influence the distribution of populations 21. More recently it has been demonstrated that nursery areas are of utmost importance for maintaining sustainable breeding populations 19, 20, 21. Nursery areas are considered to be crucial for the recovery and persistence of shark populations 18. The finding of nursery areas in the fossil record suggests they have been essential habitats for some shark species throughout evolutionary time.

megalodon from the late Miocene of Panama and Carcharhinus brachyurus from the late Miocene of Peru 13, 14, 15, 16, 17. Identified shark palaeo-nurseries areas span widely chronologically, geographically, and taxonomically, e.g., hybodontiforms and xenacanthiforms from the late Triassic of Kyrgyzstan lamniforms from the Palaeocene of South Carolina, USA Otodus from the late Miocene of South Carolina O. Accordingly, nurseries areas in the geological past (herein palaeo-nurseries) have been proposed based on the criteria for modern species, but adapted to the fossil record (1) water-depth: they are shallow-water habitats hence offering young with protection from larger predators 12 (2) productivity: they are highly productive habitats providing abundant resources and facilitating growth 2 (3) preponderance of young individuals: they are heavily dominated by juveniles and neonates 13, 14, 15, 16, 17. Although these criteria have been useful to identify modern nurseries 3, 4, 5, 6, 7, 8, 9, 10, 11, some of them can be rather difficult to apply to the fossil record. Generally, nursery areas are defined by the following criteria: there is higher relative abundance of juveniles and neonates compared to others areas immature sharks must show a tendency to return and stay for long periods of time they are used by immature sharks over years 1, 2 and they are geographically discrete zones that provide two main benefits: protection from predation and abundant food resources 1. Shark nursery areas are essential habitats where young are born or reside, and where their growth is facilitated 1.

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