Banc d'Arguin National Park as grey heron ("Ardea cinerea monicae") and Eurasian spoonbill ("Platalea leucorodia balsaci") and western reef heron ("Egretta gularis") (IUCN, 1987). For marine mammals, endangered species can be seen here all-year round; for example, Mediterranean monk seals, Atlantic humpback dolphins and bottlenose dolphins. Other species can be seen here are orca, the killer whales, pilot whales, Risso's dolphins, dolphins (common, rough-toothed). Fin whales and harbor porpoises are also known to visit the area. Possibly, highly coastal whale species such as North Atlantic right whales, now-extinct Atlantic gray whales were used to be seen here as well. Other baleen whales possibly occur
Ultrasound whistle is a whistle that emits ultrasound, used for training and calling dogs. The frequency of most dog whistles is within the range of 23 to 54 kHz. Toothed whales, including dolphins, can hear ultrasound and use such sounds in their navigational system (biosonar) to orient and to capture prey. Porpoises have the highest known upper hearing limit at around 160 kHz. Several types of fish can detect ultrasound. In the order Clupeiformes, members of the subfamily Alosinae (shad) have been shown to be able to detect sounds up to 180 kHz, while the other subfamilies (e.g. herrings) can hear