Robert L. Brownell Jr.
Richard C. Banks
1969
<p><i>Delphinus bairdii</i><span> Dall is a species of dolphin distinct from </span><i>D. delphis</i><span> Linnaeus, with which it has usually been synonymized. </span><i>D. bairdii</i><span> has a longer rostrum relative to the zygomatic width of the skull; the ratio of these measurements falls at 1.55 or above for </span><i>bairdii</i><span> and 1.53 and below for </span><i>delphis.</i><span> In the eastern Pacific Ocean, </span><i>D. bairdii</i><span> is found in the Gulf of California and along the west coast of Baja California, Mexico; </span><i>D. delphis</i><span> is presently found in the waters off California. Until approximately the beginning of the present century, </span><i>bairdii</i><span> occurred farther north in the eastern Pacific Ocean, at least to the Monterey Bay area of California. Restriction of </span><i>bairdii</i><span> to more southerly waters, probably as an indirect result of a change in water temperature, may have permitted </span><i>delphis</i><span> to move into inshore Californian waters. The Pacific population of </span><i>D. delphis</i><span> has a somewhat shorter rostrum than the Atlantic population, and is perhaps subspecifically different. A thorough analysis of the entire genus </span><i>Delphinus</i><span> is needed before the relationship of all the populations can be understood and names properly applied.</span></p>
application/pdf
10.2307/1378342
en
Oxford Academic
Taxonomy of the common dolphins of the eastern Pacific Ocean
article