Name a species of dolphin that does not produce any whistle sounds

Name a species of dolphin that does not produce any whistle sounds
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The winner of last week’s quiz was voyager, who correctly stated that hind limbs can be seen in a developing dolphin embryo – these limbs will disappear by the time the dolphin is born. Now, for this week’s quiz: name a species of dolphin that does not produce any whistle sounds.  Think you know the answer? Surf on over to thedolphnipod.com and click on Dolphin Quiz – leave your answer in the comments section. Winners will randomly be chosen from the correct answers, and will be announced on next week’s show.