[5] Common bottlenose dolphins inhabit temperate and tropical oceans throughout the world,[2][6] absent only from polar waters.

Common bottlenose dolphins have a grey coloring, a short beak, a single blowhole, and a hooked dorsal fin.

The clade containing the offshore, Mediterranean, and Black Sea populations was sister to the western North Atlantic lineage, indicating deep divergence between the two.

[citation needed] Dolphin use of their blowholes and nasal sacs to communicate and their ability to echolocate with their melon are keys to their success.

As sound waves are emitted they are bounced back and received as nerve impulses in the brain which can be interpreted at a frequency of 120 kHz.

This allows dolphin to know the location, shape and size of objects aiding in navigation, communication, hunting, and awareness of predators nearby.

Along the U.S. Atlantic coast, the main prey includes Atlantic croakers (Micropogonias undulatus), spot (Leiostomus xanthurus) and American silver perch (Bairdiella chrysoura), while in South Africa, African maasbankers (Trachurus delagoa), olive grunters (Pomadasys olivaceus), and pandora (Pagellus bellottii) are common bottlenose dolphin's typical prey.

[27] Research indicates that the type and range of fish in a dolphin's diet can have a significant impact on its health and metabolism.

[29] While communicating with each other, bottlenose dolphins grab ahold of each other with their teeth, which forms unique knicks and notches on the dorsal fins making them individually identifiable.

[citation needed] Common bottlenose dolphin signature whistles, which are in a higher frequency range than humans can hear, have an important role in facilitating mother–calf contact.

[31] The researchers stated that CDS benefits for humans are cueing the child to pay attention, long-term bonding, and promoting the development of lifelong vocal learning, with parallels in these bottlenose dolphins in an example of convergent evolution.

[36] Females typically reproduce every 3 to 6 years when sexual maturity is reached, and there is no recorded menopause in the bottlenose dolphin species.

Dolphin communities out in the deep ocean have more threats with shark attacks but living in pods allows them to survive.

[49] It has also been trained for military uses such as locating sea mines or detecting and marking enemy divers, as for example in the U.S. Navy Marine Mammal Program.

[60][61] Tião was a well-known solitary male bottlenose dolphin that was first spotted in the town of São Sebastião in Brazil around 1994 and frequently allowed humans to interact with him.

Fungie was another solitary male bottlenose, living in close contact with humans in Dingle Harbour, Ireland, from 1983 until his disappearance in 2020.

[63] A lonely and potentially sexually frustrated dolphin was blamed in August 2024 for a spike in attacks on swimmers in Mihama, a Japanese seaside town.

[64] The North Sea, Baltic, Mediterranean and Black Sea populations of the common bottlenose dolphin are listed in Appendix II[65] to the Convention on the Conservation of Migratory Species of Wild Animals (CMS) of the Bonn Convention, since they have an unfavorable conservation status or would benefit significantly from international cooperation organized by tailored agreements.

Environmental impacts or changes from chemicals or marine pollution can alter and disrupt endocrine systems, affecting future populations.

A recent study[71] suggested signs of lung disease and impaired stress in 32 dolphins that were captured and assessed in Barataria Bay, Louisiana, US.

Out of these 32 dolphins, 10 were found pregnant and, upon a 47-month check up, only 20% produced feasible calves, compared to a previous success rate of 83%, in the same area.

Dense human development along the eastern coast of Florida and intense agricultural activity have resulted in increased freshwater inputs, changes in drainage patterns, and altered water quality (i.e. chemical contamination, high nutrient input, decreased salinity, decreased sea grass habitat, and eutrophication.

Harmful algal blooms are responsible for dead zones and unusual mortality events of common bottlenose dolphins consuming these toxic fish from the brevetoxin produced by the dinoflagellate Karenia brevis.

[74] Brevetoxins are neurotoxins that can cause acute respiratory and neurological symptoms, including death, in marine mammals, sea turtles, birds, and fishes.