One of the most valuable and non-invasive tools to learn about whale and dolphin populations is to use photographic identification. All species are highly mobile, and may only be in an area for a short period of time. When whale watching Australia, others are found far from shore and some whales undertake migrations of epic proportions, all factors that make them difficult to study.
Here is an infographic that looks at the characteristics researchers use to identify the cetaceans we encounter.
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Co-founder and Vice President of SearchRank, responsible for many of the day to day operations of the company. She is also founder of The Arizona Builders' Zone, a construction / home improvement portal.