[4] Some behavioral and morphological data support moving Peale's dolphin to Cephalorhynchus.

Peale's dolphin also shares with several Cephalorhynchus species the possession of a distinct white "armpit" marking behind the pectoral fin.

On the Atlantic side, sightings typically diminish at about 44°S — near Golfo San Jorge, Argentina.

The total population is unknown, but recent research estimates there to be ~21,800 individuals in the South Atlantic part of its range.

[6] In the southwestern South Atlantic, Peale's dolphin forages in the coastal ecosystem, feeding mainly on the demersal and bottom fish such as southern cod and Patagonian grenadier; also octopus, squid, and shrimps have also been found in stomachs examined.

[6] Peale's dolphins' propensity for moving over only small areas, and staying close to shore, has rendered them vulnerable to interference by man.

During the 1970s and '80s, Chilean fisherman killed and used thousands of Peale's dolphins for crab bait each year.

It is listed on Appendix II[7] as it has an unfavourable conservation status or would benefit significantly from international co-operation organised by tailored agreements.