Marine megafauna occurrence was recorded in the deep-sea region bordering the abyssal plain ~400 km north-west of Luanda, Angola. The survey took place during an Environmental Baseline Study (EBS), prior to drilling exploration activities, with the goal of characterizing the habitat and biodiversity of the region. Offshore shipboard surveys were conducted during September 2018 in water depths ranging from 2350–3850 m. We recorded daytime sightings of marine mammals and sea turtles and at night made audio recordings using passive acoustic monitoring (PAM) methods focused on capturing the sounds of vocalizing marine mammals. A variety of species were visually detected, including the humpback whale (Megaptera novaeangliae), sperm whale (Physeter macrocephalus), common dolphin (Delphinus spp.), striped dolphin (Stenella coeruleoalba), Atlantic spotted dolphin (S. frontalis), and olive ridley turtle (Lepidochelys olivacea). Acoustic click bouts similar to those made by several odontocete species, possibly including beaked whales, were recorded within the 25–48 kHz range. The humpback whale was the most frequently sighted species, accounting for 56% of mammal sightings, indicating a potential far offshore migratory habitat in this region. Most notably, right whales (probable Eubalaena australis) were visually observed. This is the first confirmed record of right whales in Angolan waters since the early 1900s. As development expands in this offshore region, these data can usefully inform future monitoring and mitigation strategies focused on minimizing impacts to wildlife.

The status of marine turtles in Angola, West Africa, is poorly known, and therefore during 2000–2006 a combination of both dedicated and opportunistic beach and at-sea turtle surveys were carried out, and interviews conducted with fishing communities and at markets. Green Chelonia mydas, olive ridley Lepidochelys olivacea, leatherback Dermochelys coriacea and loggerhead turtles Caretta caretta were recorded, and nesting of the first three species confirmed during September–March (peaking November–December). Green turtles nested mainly in the south, leatherback turtles in north and central Angola, and olive ridley turtle nesting was widespread. Olive ridley turtle nest density at Palmeirinhas averaged 32 nests km−1. At-sea surveys produced 298 turtle records, with peak occurrence during August. Significant anthropogenic-related mortality (including exploitation of meat and eggs and fishing bycatch) was recorded, in addition to natural predation and other threats. Maintenance of the long-term sustainability of these turtle populations should focus on the involvement of fishing communities and increasing awareness throughout Angola.

Olive ridley turtles Lepidochelys olivacea nest along the east and west coasts of India, with major mass nesting beaches in the state of Orissa. The coast of Andhra Pradesh, the state immediately south of Orissa, has sporadic nesting of olive ridley turtles and is believed to form part of the migratory route of the turtles that nest in Orissa. A survey of nesting beaches and offshore waters of the Andhra Pradesh coast was carried out from November 2000 to April 2001. Preliminary interviews and secondary data were used to determine potential nesting beaches. During January–March 2001 intensive surveys of seven beaches and monthly surveys of the rest of the coast provided a lower bound of c. 4,000 nests along the Andhra Pradesh coast. Nesting densities were higher at beaches near river mouths, at 60–100 nests km−1 in northern and central Andhra Pradesh, and 15–20 nests km−1 in southern Andhra Pradesh. Sightings and incidental catch in experimental trawls indicated the presence of olive ridley turtles in offshore waters. Fisheries related mortality is the major threat to the species, with nearly 1,000 dead turtles being washed ashore during January–March, but depredation of eggs by humans and feral animals was also widespread. Conservation efforts need to address these issues, and also the effects of coastal development and artificial illumination, especially at beaches that support relatively high densities of nesting olive ridley turtles.