|
 |
 |
 |
| Note the high, slender, scythe-like dorsal fins and extensive dorsal scarring of these Risso's dolphins. [Image 2319] [Image 2314] |
A typical group of several dozen Risso's dolphins, seen underwater, Rissos dolphin, dorsal fin.Note distinguishing and highly variable skin and dorsal fin patterns, characteristic of this species. White scarring, likely caused by other Risso dolphins teeth, accumulates during the dolphins life so that adult Rissos dolphins are almost entirely white. San Diego, Grampus griseus, Image 04970 |
| Risso's dolphins (Grampus griseus) are large oceanic dolphins distributed throughout most of the world's tropical and warm-temperate waters. They typically reach 10 feet (3m) in length as adults, weighing up to 650 lbs (330kg). Research suggests that their preferred prey are squid, although they are known to predate upon fishes as well. |
 |
 |
 |
| Individual Risso's dolphins are easy to distinguish because of the unique scarring patterns borne on their dorsal fins and bodies. [Image 7601] [Image 7602] |
Extensive scarring makes this adult Risso's dolphin appear almost totally white, Rissos dolphin showing fresh scarring from social interactions with other Rissos dolphins. Note distinguishing and highly variable skin and dorsal fin patterns, characteristic of this species. White scarring, likely caused by other Risso dolphins teeth, accumulates during the dolphins life so that adult Rissos dolphins are almost entirely white. San Diego, Grampus griseus, Image 04964 |
| One distinguishing characteristic of Risso's dolphins are the white scars they acquire (and keep) throughout their lives. It is thought these scars are the result of teeth scrapes from other Risso's dolphins, injuries from parasites and/or squid. In some adults the scarring is so extensive that the animal appears nearly all white (in contrast to the dark gray color seen in juveniles and adults that have no acquired much scarring). |
 |
 |
 |
| A full breach, A Rissos dolphin leaps from the ocean in a full breach. Note distinguishing and highly variable skin and dorsal fin patterns, characteristic of this species. White scarring, likely caused by other Risso dolphins teeth, accumulates during the dolphins life so that adult Rissos dolphins are almost entirely white. Offshore near San Diego, Grampus griseus, Image 07597 |
A spyhop, A Rissos dolphin spyhops, lifting its head above water for a look. Note distinguishing and highly variable skin and dorsal fin patterns, characteristic of this species. White scarring, likely caused by other Risso dolphins teeth, accumulates during the dolphins life so that adult Rissos dolphins are almost entirely white. Offshore near San Diego, Grampus griseus, Image 07598 |
A full breach. Note this Risso's dolphin's white ventral patch (contrasting against its unscarred dark gray body) is apparent, Rissos dolphin, breaching. Note distinguishing and highly variable skin and dorsal fin patterns, characteristic of this species. White scarring, likely caused by other Risso dolphins teeth, accumulates during the dolphins life so that adult Rissos dolphins are almost entirely white. San Diego, Grampus griseus, Image 00983 |
| The typical lifespan of a Risso's dolphin is estimated to be at least 20 years and perhaps up to 40 years. They often travel in groups of five to 50 animals, and recent evidence suggests that these groups may be stable and composed of related individuals, although this has not been proven. Occasionally many groups will coalesce into a huge herd of many hundreds or thousands of Risso's dolphins. sometimes mixed with other species of dolphin as well. |
 |
 |
 |
| Rissos dolphins surfacing showing dorsal fins. Note distinguishing and highly variable skin and dorsal fin patterns, characteristic of this species. White scarring, likely caused by other Risso dolphins teeth, accumulates during the dolphins life so that adult Rissos dolphins are almost entirely white. San Diego, Grampus griseus, Image 02318 |
Rissos dolphin. Note distinguishing and highly variable skin and dorsal fin patterns, characteristic of this species. White scarring, likely caused by other Risso dolphins teeth, accumulates during the dolphins life so that adult Rissos dolphins are almost entirely white. Offshore near San Diego, Grampus griseus, Image 07591 |
Rissos dolphin. Note distinguishing and highly variable skin and dorsal fin patterns, characteristic of this species. White scarring, likely caused by other Risso dolphins teeth, accumulates during the dolphins life so that adult Rissos dolphins are almost entirely white. Offshore near San Diego, Grampus griseus, Image 07593 |
| Sri Lanka and various Asian societies (including Japan and Taiwan) hunt and consume Risso's dolphins as food. |
 |
 |
| A tail slapping juvenile Risso's dolphin, A young Rissos dolphin calf performs a tail slap. Note the dark color on this juvenile, it has yet to acquire the white scarring that distinguishes adult Rissos dolphins. Offshore near San Diego, Grampus griseus, Image 07599 |
Rissos dolphin. Note distinguishing and highly variable skin and dorsal fin patterns, characteristic of this species. White scarring, likely caused by other Risso dolphins teeth, accumulates during the dolphins life so that adult Rissos dolphins are almost entirely white. Offshore near San Diego, Grampus griseus, Image 07604 |
See also:
Atlantic Spotted Dolphin Pacific White-Sided Dolphin Hawaiian Spinner Dolphin Bottlenose Dolphin Common Dolphin |
| Keywords: Risso's dolphin photos, Grampus griseus photo, photograph, dolphin, whale, cetacean, ocean, photography, photograph, underwater, wildlife, ocean, marine |
HOME |
Online Image Search |
Photo of the Day |
Keywords |
Contact / Bio |
Licensing/Pricing |
Prints |
Stock List |
Image Hierarchy |
List of Log Entries |
Site Map |
Blue Whale |
Cetaceans |
Pinnipeds |
Sharks |
Rays |
Fishes |
Kelp Forest |
Sea Birds |
Inverts |
Man & Animal |
Man & Ocean |
Ocean & Light |
Ocean & Motion |
Portraits |
About Color and Monitor Calibration |
Copyright Statement |
Buzz |
Surf Photos |
Great White Shark Photo |
Blue Whale Photo |
All text and photographs copyright © Phillip Colla Natural History Photography
All rights reserved worldwide. The content of this site is made available for purposes of researching images offered for license by Phillip Colla Natural History Photography. No image is to be copied, duplicated, modified or redistributed in whole or part without the prior written permission of Phillip Colla Natural History Photography. Phillip Colla Natural History Photography,
8021 Paseo Arrayan, Carlsbad, CA 92009, USA. (760) 652-5350.
Email: oceanlight@OceanLight.com Web: www.OceanLight.com
Portfolios: www.Gygis.com
Updated: March 15, 2010 |
|