Risso’s Dolphin

  • Risso’s Dolphins Chase Killer Whales

    ​The ​local ​transient Killer Whales, ​the ​coastal ​ones, ​feed ​on ​Risso’s ​Dolphins. They’re ​kind ​of ​similar ​to ​a ​pilot ​whale. ​They’re ​up ​to ​12ft ​long, ​​they’re ​grayish ​white. ​They ​have ​a ​round ​shaped ​head, ​they ​don’t ​have ​the ​long ​beaks. ​Their ​head ​is ​similar ​to ​a ​pilot ​whale ​and ​they ​have a ​lot ​of ​scratch ​marks ​on ​them ​from ​the ​squid. ​So ​they ​are ​one ​of ​the ​most ​frequent ​dolphins ​we ​see ​here ​because ​of ​the ​deep ​water ​here ​and ​also ​because ​there’s ​lots ​of ​squid ​here. ​​But ​there ​was ​one ​day ​and ​this ​was ​again ​about ​20 ​years ​ago ​and ​it ​hasn’t ​happened ​since. ​But ​the ​killer ​whales ​here, ​like ​I ​said, ​have ​never ​been ​seen ​preying ​on ​the ​Risso’s ​dolphins. We ​have ​seen ​the ​Outer ​coast ​transients, ​the ​ones ​that ​feed ​on ​the ​sperm ​whales. ​​And ​​they’ve ​caught ​Risso’s ​dolphins ​twice. ​ ​But ​the ​story ​was ​that ​the ​local ​transients ​we ​were ​watching ​and ​then ​all ​of ​a ​sudden ​this ​group ​of ​about ​15 ​Risso’ ​dolphins ​came ​charging ​over ​and ​caused ​the ​group ​of ​transients ​to ​flee. ​​It ​was ​like ​a ​reverse ​thing. ​So ​these ​Risso’s ​dolphins ​were ​chasing ​and ​pursuing ​this ​group ​of ​like ​7 ​transient ​mammal ​hunting ​killer ​whales, ​which ​you ​wouldn’t ​expect ​because ​you ​would ​think ​the ​killer ​whales ​would ​be ​the ​aggressive ​mammal ​hunting ​whales. ​ And ​the ​Risso’s ​chased ​them ​for ​about ​like ​15, ​20 ​minutes. ​And ​they ​were ​all ​porpoising, ​going ​at ​a ​very ​high ​rate, ​swimming ​out ​of ​the ​water. ​And ​eventually ​the ​Risso’s ​kind ​of ​caught ​up ​to ​them ​and ​surrounded ​them ​and ​then ​everybody ​stopped. ​It’s ​like ​the ​Risso’s ​caught ​them ​into ​almost ​like ​a ​net ​because ​the ​Rissos ​surrounded ​them ​and ​I ​felt, ​felt ​like ​they ​put ​a ​net ​around ​them. ​It ​was ​like ​that ​they ​had ​surrounded ​them. ​So ​the ​killer ​whales ​were ​stopped ​completely ​in ​the ​water. ​And ​they ​were ​going ​so ​fast ​it ​was ​hard ​for ​us ​to ​keep ​up ​on ​them ​on ​the ​boat. ​But ​they ​trapped ​these ​killer ​whales ​in ​the ​ocean, ​by ​surrounding ​for ​maybe ​10 ​minutes ​or ​so. ​And ​then ​the ​killer ​whales ​broke ​loose ​and ​started ​fleeing ​again. ​​And ​then ​a ​second ​time ​the ​Risso’s ​caught ​up ​and ​trapped ​them. ​And ​then ​eventually ​the ​killer ​whales, ​got ​away ​again ​and ​the ​Risso’s ​gave ​up. ​But ​it’s ​kind ​of ​reversed ​to ​what ​you ​would ​expect, dolphins ​to ​be ​chasing ​and ​attacking ​a ​killer ​whale ​and ​the ​killer ​whales ​to ​be ​so ​frightened ​by ​them. ​ So ​that ​was ​a ​really ​interesting ​story ​that ​I ​really ​always ​remember ​and ​think ​it’s ​pretty ​cool.  -Nancy This post was adapted from a voice recording in episode 93 of the Whale Tales Podcast, listen here

  • Cetacean Highway – 8/25

    Cetacean Highway – 8/25

    The past few days have been quite busy with multiple cetacean species. One day, we encountered a small group of Risso’s dolphins that were riding the swell next to our boat. It was a lovely gesture by these dolphins, because it was a bit difficult to spot the sperm whales in the swell We casually…

  • A Great Earth Day with Orcas and Humpbacks – 22/4/25

    A Great Earth Day with Orcas and Humpbacks – 22/4/25

    What a great Earth Day it was today! We left the harbor and were greeted by a pod of Risso’s Dolphins. We had our looks at the pod and then proceeded to head south. Then about an hour later, the captain proceeded to turn the boat around and said they had reports of orcas. Surprisingly,…

  • A Wonderful Risso’s Encounter – 8/7/24

    We’ve been out and seen some Orcas in Baja recently and we were pretty far, 12 miles or so out and the Orcas just disappeared and then we saw a Risso jump and we thought that the Orcas might go after the Rissos but they didn’t. The whole pod of Risso’s then appeared and the…

  • Rissos Again – 2/8/23

    Rissos Again – 2/8/23

    Today we were lucky to reencounter Risso’s dolphins. Impressive and speedy creatures. We encountered a group that had several calves with them. It was hard to estimate the overall number because they spread out. Some of the calves were in a playful mood and threw their tail in the air to put on a show…