Field Manual: Managing encounters and sharks

This portion of the Field Manual discusses the management of collected whale shark data.

Basic assumptions

Wildbook for Whale Sharks is a mark-recapture framework for storing and analyzing whale shark data. As such, it divides data into two distinct types.

Encounters are individual sightings of whale sharks. An encounter report is submitted via the Internet and may represent (if enough data is present for identification) a “mark” (first sighting) or “recapture” (subsequent re-sighting) of an individual whale shark. Each encounter contains photos and data that represent one whale shark at one point in time. An encounter can be added to a previously identified shark in the database, representing a re-sighting of that animal, or it can be allocated as a new individual shark and given a name, representing a new animal previously undocumented in Wildbook. Encounters may also remain “Unassigned,” indicating that the encounter does not contain enough data to be identified as a new or previously seen shark at the current time, though it may be matched to other encounters in the future.

Sharks are uniquely identified animals and are made up of one or more encounters. To be assigned as a new shark, a new encounter must have a properly-oriented left-side spot pattern extracted from a photograph and added into the database. Encounters without a suitable left-side pattern can be added to an existing shark if some other characteristic (visual recognition of its pattern or of significant scarring, right-side pattern matching to another identified shark, etc.) can be used to link it to an existing shark in the Library. As we build up more and more encounters for each shark, we will be able to build up robust metrics for population analysis, allowing us to better understand whale shark biology and population trends on a local and a global scale.

Next: Approving or rejecting an encounter
Previous: Overview

 
managing_encounters_and_sharks.txt · Last modified: 2013/10/22 17:29 by webadmin     Back to top