David @ Tokyo

Here's a few items from Judy Zeh, former chair of the IWC Scientific Committee.

From 1999:

For nearly two decades, UW Statistics Professor Judith Zeh has been studying whales, using statistical analysis to learn more about the size and dynamics of bowhead whale populations. Zeh's expertise recently led to her election as chair of the International Whaling Commission (IWC) Scientific Committee.

The goal of the IWC, says Zeh, is to ensure that all stocks of whales are maintained at an appropriate level and not depleted. The Commission's Scientific Committee, made up of about 140 scientists named by 40 member governments, provides valuable information about scientific aspects of whaling.

A key piece of information about any whale population is its size. Other information might include the impact of environmental factors--environmental warming, whale watching--on whale populations, as well as identification of single interbreeding populations. Such information is significant as the Commission develops whaling policies.

As chair of the Scientific Committee, Zeh is the Commission's principal scientific advisor. She is the first woman to serve as chair in the IWC's 52-year history.

Why is a statistician like Zeh intrigued by whale research? It offers interesting challenges, she says. "Since we must study whales out in the ocean, there are intriguing statistical problems in answering scientific questions," she explains. "For example, in counting whales, how do we account for the ones we are not able to see or hear? Or when identifying whales in photos by their markings, how do we account for the ones without markings? It's the role of the statistician to account for the whales that cannot be identified from obvious data."

Zeh will serve a three-year term as chair of the IWC Scientific Committee.

Then from 2000:

... Matt Coleman asked the chair of that committee, Judy Zeh about the state of the world's whale populations.

JUDY ZEH: Most of the whale, different whale stocks and species in the world, I think, are doing fairly well right now. There are some particular populations that are of very great concern. One of those is the western North Atlantic right whales which live mostly just off the east coast of the United States, and that's a very small population which seems to be having some problems now with lower reproductive and survival rates. So the US Government is working very hard on it, but it is a big problem.

MATT COLEMAN: Environmental groups have been saying that the numbers have been decreasing very rapidly. In fact, there are probably only a few hundred northern right whales left in the world. Is that correct?

JUDY ZEH: Basically the biggest problem is that that was the population that was very badly decimated by the early commercial whaling, and it just hasn't really recovered, so it doesn't seem to be increasing as much as we would like it to. And the last few years there have been some particular problems, that we don't know whether they're related to environmental things or whether there is a bigger problem with the population status.

MATT COLEMAN: What about whale populations in the southern hemisphere? How are they doing?

JUDY ZEH: There is a lot of evidence that humpbacks are increasing very nicely in much of the southern hemisphere, so that's good news. There's less information about some of the other species like blue whales and fin whales, so we can't really say a lot about what they're doing yet. But again, if we keep doing these surveys, we'll gradually get more information about how they're doing.

MATT COLEMAN: One of the best known species of whale is the minke whale. Japan claims that the minke whale is now so abundant that commercial harvesting of that species would be sustainable. Do you agree?

JUDY ZEH: We're in the process of completing the third circumpolar survey, and looking at minke whale estimates for the southern oceans, and as far as I know at present, it's certainly true that if commercial whaling were resumed under the revised management procedure, it could be managed safely.

MATT COLEMAN: How valuable are these scientific research programs that Japan carries out in telling scientists like yourself something useful about whale populations?

JUDY ZEH: Well, they certainly do provide a lot of data. They've been doing a lot of genetic analyses which tells us about stock structure, whether whales in a particular area mix with whales from another area or whether they don't. And this is something that's very important to know for management purposes. So they certainly provide good information on things like that.

MATT COLEMAN: Would you be able to get that information any other way, through a more humane or even a non-lethal research method?

JUDY ZEH: Well, many scientists are using biopsy sampling, and that works very well for humpback whales. It's been a little less successful for minke whales, and I'm not sure that's because it hasn't been tried sufficiently and the best techniques haven't been worked out, or whether - I suspect that maybe that it's somewhat more difficult to biopsy minke whales than humpback whales.

COMPERE: Judy Zeh is the chair of the scientific committee of the International Whaling Commission which began its annual conference in Adelaide today. Matt Coleman there for us.

Zeh was apparently the convenor steering group for the recent JARPA review.
Finally, this from 2005:

CAN WHALING BE MANAGED TO PROTECT WHALES AND WHALERS?

Judith E. Zeh, UW Department of Statistics

The International Whaling Commission (IWC) was established in 1946 by the International Convention for the Regulation of Whaling, signed by 14 whaling nations, “to provide for the proper conservation of whale stocks and thus make possible the orderly development of the whaling industry”. Part of the Convention is a Schedule that contains the actual regulations regarding species and numbers of great whales that can be caught, times and places in which whaling is allowed, etc. Amendments to the Schedule, which require a 3/4 majority vote for adoption, must be “based on scientific findings”. Thus, since its inception, the intent of the IWC has been to base management on science, and one of its standing committees has been the Scientific Committee (SC). The SC meets annually, just before the Commission meets, and the Chair of the SC presents SC findings to the Commission. I will talk about successes and failures of this management process before, during, and since my 1999-2002 term as SC Chair. Successes have come when the Commission obtained and followed good scientific advice. Failures have sometimes occurred because of inadequate scientific advice, but more often because economics or politics got in the way of following good advice. Both successes and failures occurred in the 1960s, when a committee of three scientists appointed by the Commission recommended immediate protection of Antarctic humpback and blue whales from whaling and drastic reductions in fin whale catches. The Commission did protect humpback and blue whales, but delayed reductions in fin whale catches because of pressure from whaling nations. Eventually greater reductions in fin whale catches had to be made to allow the stock to recover. The management procedure developed by the SC during the 1970s proved unworkable because it required classifying whale stocks on the basis of quantities that were difficult to estimate. Meanwhile, some whaling nations stopped whaling and other nations joined the IWC. It now has 66 members, the majority of which are non-whaling nations and many of which could be characterized as anti-whaling nations. This adds a complicating dimension to the “science and policy interface”. During the 1980s, the Commission imposed a moratorium on commercial whaling that is still in effect. However, the Convention allows whaling in spite of the moratorium by nations that objected to its adoption and by any nation under Special Permits for scientific research. Meanwhile, the SC has developed a revised management procedure (RMP) that requires only regular estimates of abundance of a stock and the known catch history. The RMP was tested by simulations of 100 years of catches using it. These simulations took into account uncertainties in a wide range of factors. In my view, whales and whalers would be better protected by use of the RMP to manage whaling than by the moratorium. The SC currently provides advice on aboriginal subsistence catch limits for bowhead whales using a similar management procedure.

Labels: JARPA, Judy Zeh, Revised Management Procedure, Whaling

Annex D of the IWC Scientific Committee's report for 2006 includes an interesting summary of the process by which the current Catch Limit Algorithm (CLA) was originally evaluated and selected.

THE ROLE OF TUNING IN THE EVALUATION AND SELECTION OF THE CLA

When it came to recommending a single management procedure to the Commission for possible adoption, the Committee noted that comparison of alternative procedures is not entirely trivial, because they have to meet competing objectives. A procedure can always be modified to reduce the risk of depletion of stocks, but at the cost of allowing less catch. Likewise, higher catches can be achieved, but at the cost of a greater risk of depletion of the stock. The Committee recognised that in the presence of this trade-off, it could be difficult to compare the underlying performance of two candidate procedures if they are tuned to achieve different trade-offs between the two main objectives of catch and risk, and if only one tuning is presented.

However, if results from several alternative tunings of each procedure are available, then it may be possible, by interpolating the results if necessary, to draw conclusions about the relative performance of the two procedures.

In 1990 (IWC, 1991) the Committee therefore requested developers to present results a wide range of tunings to ensure that there would be at least some overlap in the range of risk-related performances of the different candidate procedures. In preparation for a final selection between procedures, the fourth and final Comprehensive Assessment Workshop on Management Procedures recommended that selection of a procedure be based on results for three specific tunings of each of the each of the five candidate procedures. These three tunings should be such so as to achieve a median final depletion (ratio of current to unexploited population) of the mature female population after 100 years of 0.60, 0.66 and 0.72, in a specific reference trial. The reference trial chosen was the so-called D1 trial. "The D1 trial was chosen because it reflected the greatest discrimination between the preferred tunings of the various developers; the highest and lowest final population values adopted for tuning purposes reflected the range covered by thesepreferred tunings" (IWC 1992a).

A set of 12 trials was selected for performance comparison, in addition to a number of robustness trials for which it was merely required that a procedure perform "acceptably". Fourteen basic performance statistics were provided for each trial, but comparison between procedures was to be made on thebasis of just 18 composite statistics calculated from the core set of 12 trials (IWC 1992b). The Committee selected one of the five candidate procedures on this basis, for recommendation to the Commission (IWC 1992c). The Commission accepted the recommendation and selected one of the three tunings presented, the 0.72 tuning (IWC 1992d).

DISTINCTION BETWEEN TUNING TARGETS AND PERFORMANCE CRITERIA

The denomination of the selected tuning in terms of a median final depletion to 0.72K in the D1 trial has caused considerable confusion within the secondary literature on the RMP. The tuning level of 0.72 has frequently been erroneously interpreted as a management target, when in fact it was only for comparative purposes for assessing the relative performance of alternative procedures. No special weight was placed by the Scientific Committee on either the D1 trial, nor on the median final depletion as a performance measure.

Of the eight risk-related performance measure used for management procedure selection, only two related to final depletion and six related to the lowest depletion over the 100-year period. The D1 trial was chosen because of the discrimination it offered between procedures, not because it was a typical, central or average trial in any sense. On the contrary, it was a relatively extreme trial in that it was based on the lower extreme of the range of MSY rates (1%, 4% and 7%)considered across the trials. For MSY rates in the middle of the range (i.e. the 4% trials), the median 100-year depletion was considerably higher.

The Committee based its selection of the current CLA on the consideration of a number of performance measures (18 in all). The actual final depletion level achieved by any catch limit algorithm, whether after 100 or 300 years, depends on the details of the specific trial. The current CLA, which has a nominal tuning level of 0.72, will only actually exhibit a median final depletion of 0.72 in the precise reference trial used for tuning purposes.

Very interesting - I admit to being including amongst those who were mistakenly thinking that 0.72K (i.e. 72% of the estimated carrying capacity) was a kind of management target.

As the extract notes, the "D1 trial" is "relatively extreme" in that it assumes an MSY rate of 1%, and that in the case of an MSY rate of 4%, the resulting size of the managed population would be "considerably higher" than that (0.72K). I wonder just how much "considerably higher" is?

Whatever it is, having taken this on board one can understand more keenly than ever why Greg Donovan, Head of Science at the IWC describes as "very limited" the levels of catch that would be permited under the RMP for only abundant whale stocks, and why Doug Butterworth described the RMP as being "so risk averse that the only real scientific basis for questioning its immediate implementation is that it is so conservative that it will waste much of a potential harvest".

(Greg Donovan's article "The International Whaling Commission and the Revised Management Procedure" is a good introduction to the material above)

Labels: Revised Management Procedure, Whaling

The IWC's Scientific Committee is set to hold what is (for me at least) a long awaited review of the original JARPA programme.

The programme is consistently panned by the general public in west, where it is "common knowledge" that the JARPA programme is a "a cover for commercial whaling".

This is despite the finding in the previous JARPA review held by the IWC Scientific Committee in 1997, that

"while JARPA results were not required for management under the Revised Management Procedure (RMP), they had the potential to improve it in the following ways: (1) reductions in the current set of plausible scenarios considered in RMP Implementation Simulation Trials; and (2) identification of new scenarios to which future Implementation Simulation Trials will have to be developed (e.g. the temporal component of stock structure). The results of analyses of JARPA might allow an increased allowed catch of minke whales in the Southern Hemisphere without increasing the depletion risk above the level indicated by the existing Implementation Simulation Trials for these minke whales."

Right since the 1997 IWC plenary meeting which considered the results of this report, representatives from nations such as my homeland of New Zealand have constantly selectively quoted from this review the four words "not required for management", while ignoring the subsequent comments noting the potential of the JARPA results to improve management. Of course, New Zealand amongst others, is against management improvements for political reasons.

Well, jumping forward to 2006, the IWC Scientific Committee will conduct a new review of the now completed JARPA programme from the 4th to 8th of December. We of the general blogosphere and public won't hear about these results until the IWC meeting in Anchorage, Alaska, next May (unless someone leaks the some of the conclusions). However, the IWC Scientific Committee homepage has the following details on the workshop:

The Scientific Committee has agreed to hold an intersessional scientific workshop to assist in its review of the results of the Japanese special permit research in the Antarctic (JARPA) programme, 1987/88-2004/05. The objectives of the review are to evaluate:
1. how well the initial and revised objectives of the research have been met;
2. other contributions to important research needs;
3. the relationship of the research to relevant IWC resolutions and discussions, including those dealing with the Antarctic marine ecosystem, environmental changes and their impact on cetaceans and Committee reviews of special permit research; and
4. the utility of the lethal techniques used by JARPA compared to non-lethal techniques.

The Committee agreed that the review will consider only scientific issues; ethical issues are beyond its competence. This will be taken into account in the discussion under item (c). The Committee also agreed that some discussions of the respective merits of lethal and non-lethal methodology (item (d) is important and that Invited Participants can contribute to that debate. However, the Committee noted that main focus of the review workshop will be on Items 1-8 of the draft agenda; the more contentious issues under Item 9 will mainly be discussed at the subsequent annual meeting (JCRM 8, pp48).

It may be of interest to lay observers to know who the Invited Participants will be. The names are listed below, available from this document.

Invited Participant	Expertise
A. Aguilar	Environment
P. Best	Biological parameters
I. Boyd, Director, Sea Mammal Research Unit, UK	Feeding ecology
D. Butterworth	Abundance, biological parameters
T. Haug	Feeding ecology
R. Hoelzel	Stock structure
D. Palka	Abundance estimation
P. Palsboll	Stock structure
A. Punt or T. Polacheck	Statistical catch-at-age analyses
T. Schweder	Abundance, biological parameters

I look forward to the outcome of the workshop being made public, although as was the case in 1997, some nations will inevitably selectively quote from the report. Exposing such behaviour is one of the reasons I write this blog.

Several of the documents that will be reviewed at the workshop are already available on the review homepage, covering a range of topics.


The week after the JARPA review, the IWC SC will also be holding the second intersessional RMP workshop to progress work on the Western North Pacific Bryde's whale implementation. The completion of this work at the 2007 IWC Scientific Committee meeting will put the IWC/SC in a position to advise on safe commercial catch limits for the Western North Pacific Bryde's whale, which Japan is interested in utilising, although it seems unlikely that a 75% majority at the IWC will agree for such a commercial hunt to be permitted.

The report of the first intersessional workshop, which was considered at this year's IWC SC meeting in St. Kitts and Nevis is available here.

Labels: JARPA, Revised Management Procedure, Whaling