Flukes: A Whale's Fingerprint

During this activity, students will explore the unique nature of a whale's fluke.  They are, in essence, a whale's fingerprint. Each fluke varies in shape, size and pigmentation. The image below shows the main parts used when referencing the fluke.

Throughout a whale's lifetime, scarring occurs as a result of daily life and encounters with predators. Interestingly, white flukes tend to scar black and blacker flukes tend to scar white. Nevertheless, this serves as an additional feature that adds to each fluke's unique appearance.

During the 1960's, researchers Chuck Jurasz and Virginia Palmer developed the method of photo identification still in use today. While the equipment as become more sophisticated, the technique remains the same.  Scientists capture images of the ventral side of the whale's fluke as they descend on dives. These images are taking back to research labs and cataloged and tracked over time. The idea is simple, but the process can serve to be tricky. The Alaska Fisheries Science Center in conjunction with Auke Bay Laboratories have developed a wonderful online catalog.

This team of researchers hope to study the interactions between the populations of humpback whales around the Lynn Canal area and their favorite food source, herring. Due to their efforts, we have been provided with the opportunity to view years of research via their online database. For educators, this is a valuable resource to use with students as we strive to increase knowledge and awareness of one of this planet's largest mammals.

Now, it's your turn to try your luck at matching images of flukes. The task seems simple enough, but beware: Nothing is ever as easy as it seems!

Activity:

• Task: A group of your colleagues recently returned from a research expedition. You have been given the task of  matching the images just taken with those in your database.  As a result, you will be able to determine if their were any potential new sightings as well as update the log on those previously seen.

• Preparation: Make 2 copies of tail flukes taken from the online database at the Whale Center of New England.  Laminate and cut out the images omitting the names.  To make it easier to check if students are correct, I suggest numbering the backs of each image.