By James Joseph, Ph.D., Director, IATTC email: mscott AT
Date: Fri, 8 Dec 1995

Since 1990 when the canneries announced their "dolphin-safe" policy, the composition of the international fleet fishing in the ETP has changed. Of the 35 U.S. vessels fishing prior to the announcement, only 5 currently remain. The rest either moved to the Western Pacific, went inactive, or were sold to foreign companies. The dominant fishing countries in the ETP are now Mexico, Venezuela, Vanuatu, Colombia, and Ecuador. Despite the "dolphin-safe" cannery policies and U.S. embargos, fishing on dolphins remains the most common fishing method in the ETP. In 1994, more than half of the yellowfin tuna taken from the ETP was caught in association with dolphins. For those who are interested in eliminating dolphin sets by non-U.S. countries, this has created a problem of leverage. Having already used the weapons of market closure and embargo with little effect, how can one influence other countries to do what one wants?

Despite the continued setting on dolphins, the mortality has declined markedly since 1986 (when Mexico first began full participation in the observer program). Some have claimed that the dolphin-safe policy is to be credited for reducing the number of dolphin sets, while others claim that it is due to improved performance by fishermen in releasing dolphins. These claims can be tested by examining trends in the two main factors that contribute to total mortality: the effort (number of dolphin sets) and fishermen performance (mortality per set). Since 1986, the mortality has declined from 133,000 to 3,605 in 1993 and 4,095 in 1994 - a 97% decrease. During this same time, the number of sets has declined 27% and the mortality per set has declined 96%.

It is clear that improved performance, rather than the dolphin-safe policy, has been the major cause of the drop in mortality. The mortality levels are all below 0.14% of the population size (average 0.04%), and are much less than the conservative estimates of recruitment. Under the current U.S. PBR management approach, all stocks would be below PBR and all but three would be below the Zero Mortality Rate Goal (ZMRG).

The La Jolla Agreement of 1992 provided an impetus for this improved performance by setting limits on dolphin mortality that are to be ratcheted down each year to under 5,000 by 1999. It established individual vessel limits to promote individual responsibility by the fishermen to reduce mortality. It also established a 100%-coverage observer program to monitor the mortality for the entire international fleet in the ETP. The ETP fishery has the highest level of monitoring in the world; most other tuna fisheries that are presumed to be "dolphin-safe" have none. These other fisheries use a variety of methods, including for instance coastal gillnets that kill dolphins and other bycatch. These fisheries are not observed at sea, yet their catches can be labelled "dolphin-safe".

One of our fears, however, is that if there is no incentive to continue to participate in the IATTC observer program the countries would abandon the mortality limits and the observer monitoring of the ETP fishery altogether. The Declaration of Panama would provide this incentive by redefining "dolphin-safe" to mean tuna caught from sets with zero dolphin mortality, but would also institute the 5,000-dolphin limit immediately (down from 9,000 in 1996), set conservative individual stock mortality limits, mandate more oversight of national enforcement of infractions, and expand the management mandate to include other species that are caught as bycatch. The individual vessel limits that have ensured that the actual mortality remained less than the total limit would continue. The individual stock limits would reduce mortality to below ZMRG for all stocks and are likely to be even more restrictive than the 5,000-dolphin limit.

There are two alternatives to setting on dolphins for ETP purse-seiners: setting on tuna that are associated with logs and setting on tuna schooling at the surface (school sets). It had long been known that the bycatches associated with log sets were high, but it had not been quantified. In 1988- 1989, IATTC conducted research on Fish Aggregating Devices (FADS), as an alternative to setting on dolphins. As part of this search for alternatives, we gathered data on the characteristics of floating objects that made them attractive to tunas. This search for alternatives resulted in the first comprehensive study of "bycatches" in the ETP other than dolphins. When we quantified the magnitude and diversity of the bycatch in those sets, we extended our study to school and dolphin sets.

Preliminary studies illustrated what the tradeoffs in bycatch would be between dolphin sets and log sets. The 1993 data showed that for every 1 dolphin killed in dolphin sets, 19,542 discarded tunas, 138 mahi mahi, 25 sharks and rays, 56 wahoo, 3 yellowtail, 7 rainbow runner, 1 billfish, and 0.07 sea turtles would be killed in log sets. Our bycatch studies are in progress, and although there is considerable annual variability, the data show that log sets have bycatches that are orders of magnitude higher than dolphin sets. There is also concern about catching the typically pre-reproductive tuna in log and school sets vs. the larger adult tuna typically associated with dolphins. If the fishery were to completely switch to "dolphin-safe" sets, we don't know what the environmental effects of such large bycatches would be and we don't know what the effect of catching mainly juveniles would have on the tuna population (due to poor correlation within the range of our observations between stock and recruitment).

Earth Island has presented several arguments via MARMAM concerning the tuna- dolphin issue. What follows are my comments concerning the Earth Island remarks (Earth Island comments are in Italic, my comments are not).

  1. Total ETP Bycatch is Less Now than Before the Implementation of Dolphin-Safe Policies. Both dolphin and fish bycatch has been reduced significantly compared with the levels experienced in the 1970's and 1980's. Many vessels have left the tuna fishery of the ETP, as a result of both general economics as well as due to dolphin protection restrictions. Therefore total ETP sets (including sets on logs and on schools of tuna) have decreased significantly.

The thrust of the Earth Island argument is that because much of the U.S. fleet has been forced from the ETP to the western Pacific, that effort in all types of sets and subsequent bycatches have declined in the ETP. This assertion ignores several facts. The first is that just because boats have moved to the western Pacific doesn't mean that their sets on logs and school fish are now free of bycatch. All that has been achieved is to increase bycatches elsewhere. The data available for the western Pacific indicate that the bycatches in log sets there affect a similar community of species as in the ETP, and that the mortality rates for those species are similar. Another fact that they avoid discussing is that the dolphin-safe policy has resulted in little change in the fishing behavior of the non-U.S. fleets. One reason that the non-dolphin bycatch has not changed greatly in the ETP is because fishing practices of the non-U.S. fleet have not changed greatly.

For example, according to the Inter-American Tropical Tuna Commission (IATTC), the number of vessels in the ETP has declined from 132 vessels (126,045 tons capacity) in 1974 to 99 vessels (102,951 tons capacity) in 1994, a 25% reduction. Furthermore, in 1974, there were 7,759 sets on dolphins, 3,384 sets on floating objects, and 7,466 sets on schools of tuna, while in 1994 there were 5,948 sets on dolphins, only 1,750 sets on floating objects, and only 5,786 sets on schools of tuna. Dolphin sets have decreased 23.2%, log sets have decreased by 48.3%, and school sets have decreased by 22.6% in the past twenty years.

I cannot determine from where the 1994 number of sets was obtained, but they are wrong (likely due to misinterpreting partial data for the year). Earth Island then attempted to explain the lower effort in 1994 compared to 1974 as a response to dolphin-safe policies introduced in 1990. Perhaps a better comparison would be to look at the years just prior to and after 1990. This way, one doesn't confound one's interpretation with other factors that have contributed to decreases in the number of sets over this 20-year period:

  1. the movement of the U.S. fleet to the western Pacific during the early 1980's (unrelated to the dolphin issue),
  2. the decrease in small seiners (not included in Earth Island's figures) which was not due to the dolphin-safe policy because these seiners fished almost completely on log and school sets,
  3. the expansion of the fishery from a coastal one where a high proportion of the sets were on logs and schools sets to a more pelagic one where dolphin sets predominate, and d) the catch-per-set is almost 50% greater in the 1990's, the technology has improved, and a fisherman need not make as many sets to catch the same amount of fish.

If we compare the average number of sets from the observer data base before and after 1990, we can better determine the effect of the dolphin-safe policy on effort. The average number of dolphin sets declined 27% from the 1986-1989 period vs. the 1991-1994 period, but there was little change in the number of log sets (+4%) and school sets (-5%). The change is mostly due to the movement of the U.S. fleet to the western Pacific.

The comparison with 1974 does, however, present a cautionary example. In the early to mid 1970's, excessive effort led to overfishing of the coastal areas, a decrease in the average size of the tuna caught, and a lowering of the productivity of the fishery. An international ban on fishing on dolphins would again concentrate virtually all the effort in the coastal areas where most log and school sets are made. This concentration of effort could recreate the problem of overfishing that occurred in the 1970's.

The changes in the numbers of dolphin, log, and school sets has been driven by several factors: movements of boats, reductions in fleet size due to economic conditions, and environmental variability (e.g., high-productivity anti-El Nino events occured in 1974-1975 and 1988-1989 and a moderate, prolonged El Nino occurred during 1991-1994). Our point is that anything which causes the number of log sets to increase will most likely increase the bycatch of other fish and sea turtles.

  1. ETP Purse-Seine Fishing Has Low Bycatch Compared with other Fisheries Worldwide"

The reason the ETP purse-seine fishery has low bycatches is because of the predominance of sets on dolphins, which have lower bycatches than most other ways of fishing. For sets on logs, the bycatch rates of tunas and of other species make it a much less desirable type of fishing.

  1. The IATTC's Professed Concern About Bycatch is Phony. In its history, the IATTC has never instituted measures to limit bycatch."

Up to now, the emphasis of IATTC bycatch programs has been on reducing incidental dolphin mortality. Even the initial development of our bycatch database came as a result of the dolphin-mortality reduction program. Our intention was not to raise a bycatch issue, it was to characterize the communities associated with objects. These data were collected even before there was a dolphin-safe policy.

The bycatch database is now one of the largest in the world, and when there are enough data to make sensible recommendations, alternatives for bycatch reduction and management will be offered to the member countries. We have already begun to circulate among the fishermen and the nations some technological solutions that have been succesful in other fisheries to reduce bycatches in purse-seines and the IATTC has been particularly active in exploring management schemes for bycatch reduction. The Declaration of Panama includes a commitment to continue the research and to develop a strategy to manage bycatches. From that point of view, the Declaration advances several ecological concepts that anyone should recognize as giant steps forward.

  1. There is No Available Data to Suggest that Bycatch is Depleting Any Species, Except Dolphins.

In my opinion, this is a resounding denial of the Precautionary Principle, a denial usually associated with industry rather than with an environmental group. From the scientific point of view there are many issues about the management of bycatches that are not well understood, but I think that there is nothing wrong in considering actions to reduce them because of: (a) potential reduction of marine biodiversity, (b) potential impacts on populations whose status is not known, (c) the waste of resources, and (d) the waste of life. Even if one is mainly interested in dolphins, one should at least acknowledge that high mortalities of so many other top trophic-level predator species could have harmful effects on the marine ecosystem.

In an August 31, 1995 letter to Rep. Gerry Studds, the U.S. National Oceanic and Atmospheric Administration (NOAA) stated that:

"Quantitative estimates of bycatch ratios for non-dolphin, non-tuna bycatch must await cooperative analyses with the IATTC. While it is apparent that this bycatch includes a great number of individuals of a wide variety of fauna, it cannot be determined without comparative data on population levels whether the observed levels of bycatch are a problem for the populations involved."

This quotation refers to the current situation in which dolphin sets are the predominant fishing method and not to what would happen if there was a major shift of fishing effort to log sets. What is not cited are the NMFS conclusions that run counter to Earth Island's arguments:

  1. "Essentially, the dolphin 'bycatch' problem in the ETP has been solved. The mortality of the dolphin stocks affected by the fishery is currently far below even the minimum assumed replacement rates for these stocks."
  2. "This level of [dolphin] bycatch mortality will have little effect on stock survival or recovery."
  3. "NOAA's U.S. tuna bycatch data show that log sets tend to produce about 100 times, and school sets about 10 times, the tuna bycatch produced by dolphin sets, on a tonnage per set basis."
  4. "A conservative management approach in the face of sparse information would be to select the harvest strategy that minimizes bycatch of long-lived, easily depleted species such as the sharks and sea turtles captured in particular in log sets."

If finfish bycatch was impacting ETP tuna stocks, one would expect to see a decline in tuna stock recruitment. In fact, although the IATTC has predicted a decline for the past several years, based on finfish bycatch rates, no reduction in tuna stocks has been reported. On the contrary, the IATTC has documented that yellowfin and skipjack tuna stocks in the ETP are in excellent condition.

The IATTC has made it clear that there is no apparent correlation between the size of the spawning stock and the recruitment and thus no predictions can be made yet about what the effect on the tuna population would be if undersized fish are taken and discarded. We have not predicted a decline for the past several years, even though recruitment has actually declined. We believe that this is due to natural variability in recruitment. If the dolphin-safe policy had succeeded in switching effort from large tuna associated with dolphins to small tuna from school and log sets, we can predict that the average size of tuna in the catch would decrease, and that catching tunas at smaller sizes by itself would have had a negative effect on fishery production. This reduction would not include any effects of discarding small yellowfin. Because dolphin-safe fishing has not been widely adopted, one would not expect such predictions to have come to pass. With the data currently available, we have no way to determine any additional negative effects caused by the increased bycatches of juvenile tuna, but it is unlikely that killing millions of pre- reproductive tunas would have a positive impact on the fishery.

The ETP fishery is an extremely misplaced focus for concern on the worldwide bycatch problem.

To me, this statement illustrates the different values held by animal rights activists vs. environmentalists and ecologists. For the animal rights activist, the fate of a charismatic mammal such as a dolphin is paramount. To the environmentalist, the ecosystem and its component populations are even more important. For the animal rights activist, the concern about the mortality of millions of top-level predators is "misplaced", and the spending of millions of dollars to move one killer whale to a better captive facility is not. Until now, we have often assumed that what is good for dolphins is good for the environment. Yet, here we are presented with fishing alternatives in which we are attempting to balance the low mortalities of dolphins and the high mortalities of other marine predators, and attempt to divine the potential effects on the ecosystem of each alternative while lacking basic information on marine populations. This is the type of trade- off that the environmental groups that negotiated the Panama Declaration had to grapple with.

  1. Claims that High Sea Turtle Kills are Intrinsic to ETP Purse Seining are Bogus. Several organizations, primarily Center for Marine Conservation, claim that they must support the return to setting nets on dolphins as a way of protecting endangered sea turtles. This is a gross distortion of actual practice. First, the killing of sea turtles in the purse-seine fleet is totally dwarfed by the true culprit in sea turtle mortality, the shrimp trawling fleet.

I agree that other sources of sea turtle mortality are likely more important than the purse-seine fishery. Is that a justification for inaction or lack of concern? To dismiss the incidental mortality of an endangered species on grounds that other fisheries cause worse problems is hardly a conservation- minded strategy.

Secondly, in the rare instances in which sea turtles are entangled in the ETP tuna fishery, the vast majority can be released alive. Christopher Croft, a NMFS observer on tuna vessels for four years states:

"In my entire four years on ETP tuna vessels, not once was a sea turtle drowned in the nets. The few sea turtles that were caught were only killed if the crews decided to kill them to eat them."

The IATTC has failed to release the data as to how many sea turtles per year were killed in the nets, not by the crews. As noted above, the IATTC has also failed to set any kind of regulation or recommendation that sea turtles be released alive or that inshore log sets be restricted in any way to avoid bycatch of turtles and other species.

Earth Island concludes that "the vast majority can be released alive" based on anecdotal evidence from an observer that made six trips in the 1980's, only on U.S. boats that set primarily on dolphins and predominantly in areas which are not known to have a high concentration of sea turtles. The IATTC has collected data from almost 19,000 sets of all kinds in 1993-1994, by vessels of all flags fishing in all areas of the ETP.

In our last annual meeting we presented preliminary estimates of sea turtle mortality in 1993 and 1994. They were only stratified by set type, but not by other factors that can also be important, so they should be considered with caution. The tables containing those figures were distributed to those in the audience that requested them, including members of environmental organizations. The mortalities for 1993 and 1994 were 295 and 167 sea turtles respectively. The mortality rates per set were 2.5-5 times higher in log sets than in dolphin sets. Again, if the dolphin-safe policy had succeeded, these mortality levels would have increased.

I would like to see action taken by the member countries to reduce mortality of sea turtles. I am hopeful that the Declaration of Panama would bring the issue to the forefront. The solutions are very simple, and they could eliminate most of the mortality.

  1. Proponents of Bycatch Reduction in the ETP Fail to Follow Proper Science. Sound science dictates that bycatch reduction should focus on the protection of species with the lowest reproductive potential.

Sound science doesn't focus on just one factor to the exclusion of all others. Bycatch reduction programs need to consider a series of factors which include the conservation status of a population, their population sizes, the sustainability of the mortality, other sources of mortality, the reproductive potential of the species, the age, sex, and size composition of the bycatch, the ratio of bycatch to catch, the economic and social impacts of the measures proposed, and the uncertainty caused by lack of knowledge for these factors. It is not surprising that the environmental groups concerned about the mortality of sea turtles would give great weight to their endangered status.

In the ETP, that is, without question, the dolphin populations.

Question: what about sea turtles and sharks? Sea turtles mature at 20-25 years - much later than dolphins. While they may lay a few thousand eggs in their lifetime, only about 1 in 1,000 survives to become a breeding adult. Dolphins could be having grandcalves or even great-grandcalves before a sea turtle breeds once. Sharks likely have similar reproductive potentials as dolphins: silky sharks mature at 7-9 years, with higher fecundity (0-14 pups annually), but with lower juvenile survivorship than dolphins. The main differences in the assessment of impacts on sea turtles, sharks and dolphins are that: a) for sea turtles we have some idea about their population status, and they are all endangered or threatened, b) for the dolphins we have estimates of population sizes and we know that the current mortality is low enough to allow the populations to recover, and that even the smallest stock is close to 400,000 dolphins, and c) for sharks we know hardly anything except that mortalities in log sets are high. We do know that the dolphin mortality is sustainable, but we don't know whether the shark or sea turtle mortality is sustainable. Shouldn't we apply the Precautionary Principle to other species as well as dolphins?

The ETP tunas and other pelagic species of finfish (mahi mahi, rainbow runners, billfish, trigger fish, etc.) have extremely high reproductive potentials compared with dolphins.

This list is very selective. Why were species with low reproductive potential such as sharks and sea turtles excluded. As indicated in the equation above, to catch an equivalent amount of tuna, almost 25 sharks will die in log sets for every dolphin killed in dolphin sets. Given the recent alarm about the decline in shark populations, surely these species should not be ignored.

Two of the principle dolphin stock targets have been demonstrated to be severely depleted -- far below any depletion level demonstrated for species with far higher ability to recover. The Northeastern offshore spotted dolphin is at only 23% of its initial population -- and shows signs of continued decline. The Eastern Spinner dolphin is at only 44% of its initial population. Allowing a return to the killing of these populations in order to reduce finfish bycatch is hardly an acceptable environmental trade-off.

The phrase "Allowing a return to the killing of these populations..." implies that there is no mortality today (which is false) and that there will be a higher mortality in the near future. The environmental groups that negotiated the Declaration of Panama insisted on lowered dolphin mortality limits (e.g., in 1996 the limit would drop from 9,000 to 5,000) and imposing individual stock limits based on the PBR approach. The statement also fails to recognize, that if these efforts had not been made, the countries participating in the La Jolla Agreement would have little incentive to continue adhering to any mortality limits or to allow independent shipboard observers to monitor the mortality.

A proposal, such as the 'Panama Declaration', that allows higher bycatch of severely depleted dolphin populations as a method of reducing fish bycatch, is scientifically indefensible.

This statement is false. The Declaration of Panama doesn't allow higher dolphin mortality, it lowers the limit.

  1. Weakening Dolphin-Safe Restrictions, as Proposed, Would Actually Increase the Total ETP Bycatch.

This argument again ignores the fact that the vessels in the western Pacific are currently setting on logs which result in high bycatches. We can't predict whether fishermen will incur the expenses of moving to the ETP, and what effect their entrance will have on the ETP fishery and neither can anyone else. We do know that the Dolphin Mortality Limit of 5,000 will be applied regardless of how many vessels enter the fishery.

The IATTC has failed to implement available methods of reducing ETP finfish and sea turtle bycatch without sacrificing dolphins.

I am very interested in testing some technologies and instituting management policies that could reduce fish and sea turtle bycatch. The present relationship between the U.S. and the other nations vis-a-vis the tuna-dolphin issue, however, has made it difficult to find the willingness and the economic support to start such a program. In an atmosphere clouded by embargoes, boycotts, and animosities, it is very difficult to achieve these objectives. Hopefully, the more harmonious environment generated by the Declaration of Panama, that brings together nations, environmental groups and fishermen, will prove a more fertile ground for these initiatives.

James Joseph, Ph.D.

Link to: HSUS Wildlife response

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