Photo-identification data represent the single most important data source for the assessment of western gray whales.
Two research groups have ongoing western gray whale (WGW) photo-identification (photo-ID) programmes centred on the northeastern Sakhalin Shelf.
- The Russia-USA programme has been working there since 1995,
- and the Institute of Marine Biology (Vladivostok) group has been working there since 2002.
At WGWAP-2 in April 2007, the Western Gray Whale Advisory Panel (WGWAP) agreed to establish a task force to review and cross-match the two programmes’ photo-ID catalogues. The aim was to facilitate cooperation between the two teams in terms of joint analses and, in turn, developing recommendations for future work. The Photo IF Task Force was composed of scientists from each of the two teams, in addition to interested Panel members, external outside expert(s) (as needed for specific tasks), and nominations from Sakhalin Energy.
The objectives of the Task Force, as stated in its terms of reference were to:
- Compare the Russia-USA and Institute of Marine Biology (IMB) catalogues and arrive at an agreed list of known individuals;
- Suggest appropriate further collaboration, taking into account the need for annual updating of the comparison, and for consistency in: (i) identification of new individuals;(ii) identification of re-sightings; and (iii) classification of photograph quality.
- Consider ways to reduce photo-ID-related disturbance to whales, while maintaining sufficient data collection for population assessment and for addressing other important scientific questions.
The methods to be used to meet those objectives were to:
1. Cross-match the two existing catalogues. The cross-matching was to be carried out by the people involved in the development, compilation and curation of the catalogues as well by one or more experienced external matchers to:
- Determine, for each whale in each catalogue, which whale, if any, it matches in the other catalogue;
- Resolve doubtful cases, if necessary by examining all available photographs of the whales involved at a Task Force workshop;
- Review and discuss the report of the independent expert.
2. Hold a three-day workshop in order to discuss and, if possible, make recommendations concerning further work, including:
- Consistent protocols for the assessment of photograph quality, matching of individuals, and inclusion of definite and candidate new whales in the catalogues (including field methods and “laboratory” procedures);
- Arrangements for annual updating (cross-matching of new additions to each catalogue each year);
- Matching of photographs submitted by third parties;
- Scientific questions that could be addressed using the photo-ID data (including examples of analyses conducted to date – such as population assessment – and potential analyses that could be performed);
- Facilitation of collaborative analyses, taking into account questions of protection for data owners.
- Consideration of ways to reduce photo-ID-related disturbance to whales, while maintaining sufficient data collection for population assessment and for addressing other important scientific questions.
3. Report back to the WGWAP at its 3rd meeting on the results of the cross-matching, including summary statistics of the matching process, recommendations for further collaboration, and any outstanding issues or problems.
The first item in the above list was addressed in three steps. First, CD’s of the two catalogues were exchanged by the teams (completed in January 2007). Second, each team conducted an initial in-house cross-matching of the catalogues and the results, including comments and questions and indicating all matches considered uncertain. Finally, by agreement of all parties, an external, independent expert reviewed the results of each team’s cross-matching exercise and provided comments and advice, particularly with respect to inclusion and matching criteria, and uncertain matches. The expert’s final report was provided to the Task Force in September 2007.
The second item was fulfilled by a workshop held in Vancouver, Canada, 12-14 October 2007. As specified in the Task Force terms of reference, persons actively engaged in the photo-ID work attended the workshop and provided access to their respective full sighting histories and photo archives. Also in attendance were members of the WGWAP, consultants representing industry sponsors of the IMB group, the external expert and representatives of IUCN.
The third item was covered by submission of the present report link to the WGWAP for consideration at its 3rd meeting in Lausanne, Switzerland, 10-13 November 2007.
The second meeting took place in Geneva, Switzerland on April 19-20, 2009.
See the Photo-ID Task Force Report 2 (2009)
The third meeting took place in Geneva, Switzerland on December 8-9, 2009.
See the Photo-ID Task Force Report 3 (2009)