Who’s got what spots or how to identify whale sharks! The photo-ID database

One of the tasks that I and other members of the team will be doing will be to take photos of the whale sharks for ID purposes.

Just as we all have unique fingerprints which can be used to identify us, so too whale sharks have a pattern of spots that doesn’t really change over time and which is unique to each whale shark.

Click on the following to access the page on Photo-ID http://www.ecocean.org/photographing.jsp?langCode=en

Taking the ID-Photo

1. What side is recommended for taking a photo of the whale sharks spots?

2. How far away should you be to take the photo?

3. What part of the shark should be photographed?

4. What other features may also be photographed for identification purposes?

5. How does the Photo_ID database allow Brad Norman to determine the number of whalesharks that return to Ningaloo Reef.

6. How is a new whale shark to Ningaloo Reef identified?

7. Explain how using the Photo_Id database is an important technique which could possibly provide information about the whale sharks, their distribution and contribute to their conservation.

8. Sophisticated computer software has been developed to compare photos uploaded to the database and determine whether there is a match. Why would computers be used rather than getting people to leaf through photos to see if there is a match?

Now click on the tab View Sharks – this will take you into the whale shark photo-ID database.

9. How many individual whale sharks have photos in the database?

10. Do a Search for the whalesharks found at Ningaloo this year. The database allow you to search for specific locations where whalesharks are found.

Under the Search tab put in the location 1a (this is the code for Ningaloo). From your search results choose one of the sharks that has had several resightings (ie encounters >1).

• How many times has the whale shark been resighted?
• Where was it sighted?
• Were all the sightings in the same area or is there evidence that the whale shark went to other areas?
• Find the place/s the whale shark was/were resighted using GoogleEarth.
• Over what time period were the resightings?
• Does the resighting data suggest anything about whale shark behaviour?
• Does it mean that whale sharks stay in the same area and do not migrate? Explain.
• Suggest reasons why some sharks have had several encounters and others have not.
• What other data has been collected about the whale shark?
• The whale shark size is an estimation. Why do you think collecting this data is important?

11. The database of all the whale sharks encountered indicates whether they are males, female or unsure.Look at several pages of whale sharks. (Do a search for the location 1a and then tick males or females depending on which sex you are looking for).

• Is there a difference in the number of males or females encountered?
• What features allow people to determine whether a shark is male or female. (You might have to do some research on whale shark anatomy).
• Why do you think scientists want to know whether the sharks are male or female?

12. If so, what might this indicate in terms of whale shark behaviour and distribution?