The Striped Dolphin is primarily an oceanic species, found beyond the continental shelf or above the continental slope (Forcada and Hammond 1998, Panigada et al. 2008, Archer 2009, Laran et al. 2017, Panigada et al. 2017), although in some areas such as the Strait of Gibraltar and the Ionian Sea, they can be found in deep waters very close to shore (Frantzis and Herzing 2002, Cañadas et al. 2005, De Stephanis et al. 2008, Bearzi et al. 2011, Panigada et al. 2017, Bonizzoni et al. 2019).

The Striped Dolphin feeds on a wide variety of both oceanic and neritic prey, from both benthic-demersal and pelagic habitats. In the Mediterranean Sea, species such as sardine (Sardina pilchardus), hake (Merluccius merluccius), lanternfish (Lampanyctus crocodilus), European flying squid (Todarodes sagittatus) and southern shortfin squid (Illex coindetii) were found to be important prey, although dietary preferences may differ by both sex and age (Gómez-Campos et al. 2011, Meissner et al. 2012) or over time (Aznar et al. 2017). In the Strait of Gibraltar and contiguous Mediterranean and Atlantic waters, Striped Dolphins were found to feed on mainly on mesopelagic and neritic fish, but also on oceanic squid (Saavedra et al. 2022). The family Myctophidae represented the main prey in terms of numerical importance and reconstructed prey weight, followed by squids of the family Ommastrephidae and Bogue (Boops boops). The most important prey taxa according to the General Importance Index were C. maderensis, Ommastrephidae gen. spp., Notoscopelus spp. and M. punctatum (Saavedra et al. 2022). Higher number of mesopelagic myctophids were found in Striped Dolphins from the Mediterranean, while more demersal gobiids and European Hake (Merluccius merluccius) were found in those from the contiguous Atlantic, where the diet was more varied (Saavedra et al. 2022). Off Portugal, the key prey species of Striped Dolphins appear to be the sardine and blue whiting (Micromesistius poutassou), which are also species targeted by local fisheries (Marçalo et al. 2021). In the oceanic waters of the Eastern North Atlantic, lanternfish Notoscopelus kroeyeri and Lobianchia gemellarii were predominant among fish species, Teuthowenia megalops and Histioteuthis spp. among squid and Sergastes arcticus and Pasiphaea multidentate among crustaceans (Ringelstein et al. 2006). In the Bay of Biscay, Striped Dolphins also feature relatively high dietary plasticity, depending on the habitat (oceanic vs. neritic) they utilise (Spitz et al. 2006). Striped Dolphins found stranded in Scotland were shown to predominantly feed on whiting (Merlangius merlangus) and Trisopterus spp. (Santos et al. 2008).

Striped Dolphins often occur in mixed-species groups with Common Dolphins (Delphinus delphis) in several European areas (Forcada and Hammond 1998, Frantzis and Herzing 2002, Bearzi et al. 2016), which sometimes makes species identification in these groups difficult (Rogan et al. 2018, ACCOBAMS 2021, Hammond et al. 2021).

Striped Dolphins are widely distributed throughout most of European waters, including the Eastern North Atlantic Ocean, the North Sea, Mediterranean Sea, and the Macaronesian archipelagos (Jefferson et al. 2015). Striped Dolphins in the European North Atlantic are primarily found south of the British Isles, in the Bay of Biscay and along the Ibearian peninsula (Archer 2009, Hammond et al. 2021), although they can be seen further north, including Scotland (Santos et al. 2008, Gkafas et al. 2017). Within the Mediterranean Sea they can be found throughout the basin, but are more abundant in the western part (Aguilar 2000, ACCOBAMS 2021). They are primarily oceanic, found beyond the continental shelf or above the continental slope (Archer 2009), although in some areas such as the Strait of Gibraltar and the Gulf of Corinth in Mediterranean Sea, they can be found in deep waters very close to shore (Frantzis and Herzing 2002, Cañadas et al. 2005, De Stephanis et al. 2008, Bearzi et al. 2011). The species is absent from the Black Sea.

Existing conservation actions
The Striped Dolphin in Europe is protected under a number of treaties, including the EU Habitats Directive, ACCOBAMS, ASCOBANS, CITES Appendix II, CMS Appendix II and Barcelona Convention SPA/BD protocol Annex II.

Conservation actions needed to mitigate major threats
1) Monitor impact of measurable threats (in particular, fishery bycatch, chemical pollution, underwater noise and diseases of concern) and, simultaneously, mitigate pressures by actually regulating these human-activities. In practice, this would imply:
a) Implement a fishery related mortality mitigation framework
b) Develop and implement standardized assessment protocols to address main threats to guide stakeholders in EIAs procedures.

2) Improve the knowledge on the overall European population structure (including better sampling in offshore areas and non-sampled sub-regions).

3) Carry out the large-scale surveys (e.g. SCANS, ACCOBAMS ASI, etc.) on a regular basis, including in so-far poorly surveyed regions, such as Macaronesia. Such surveys would allow comparisons to assess temporal trends in distribution and abundance across Europe.