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In 1996, more than 12,000 green turtles (Chelonia mydas) came ashore on Raine Island on a single night (Jessop et al. 1999). Comparable nesting occurred there in 1984 (Raine Island Corporation 1985). The Raine Island population may well be vulnerable to various adverse factors. But with the available indices on nesting (Fig 1) it is hard to discern a downward trend (Fig 1); it is not on the brink of extinction. Green turtle nesting at Tortuguero has almost tripled since 1971 (Bjorndal et al. 1999). Striking increases in the number of eggs deposited on the Sabah Turtle Islands have taken place (Basintal & Lakim 1994). Sizeable populations of this species nest on Ascension Island, Tromelin, Europa, Aves Island, and in Suriname; there is no evidence of ongoing declines at these rookeries. Populations of green turtles in Hawaii and Florida are recovering.

Olive ridleys (Lepidochelys olivacea) still aggregate in huge numbers in Costa Rica, Mexico, and India. Densities are such that many eggs are destroyed by the turtles digging up each other's nests; nesting numbers at some of these beaches may be approaching carrying capacity during large arribadas. To say that sea turtle populations have been pushed to the brink of extinction world-wide is hype. But perhaps this is true of particular species?

Exhibit 2. "The hawksbill (Eretmochelys imbricata) is a Critically Endangered species throughout its range" (Mortimer 1998). The IUCN designation of Critically Endangered depends largely on the claim that the number of hawksbills in the world has decreased by 80% over the last 3 generations, something not universally accepted. Even if this were true, it would not mean the species is Critically Endangered throughout its range. In fact, hawksbill nesting is increasing in the Yucatan, on Mona Island (Puerto Rico), on Cousin Island in the Seychelles, and it appears stable on a number of other monitored beaches (references in Mrosovsky 2000). In Australia, arguably the country with most hawksbills, this species is listed as Vulnerable, not the highest category of threat in that country's classification.

Exhibit 3. Some forms of hype are more subtle than exaggerated statements about the brink. They involve understatements and mentioning encouraging developments in a lukewarm way that avoids conveying their positive nature. Putting the worst construction on things has already been criticised in the pages of this newsletter (Godfrey 1997; Pritchard 1997). Only one additional example is included here. Fig. 2 plots the number of nests of olive ridleys in Sergipe, Brazil (Marcovaldi 2001); the trend up is significant, highly so with an r² = 0.95 and p<0001. Yet the text of the paper reporting these data says that "the overall pattern seems to be steady, with a yearly mean of 200-400 nests."

Exhibit 4. Hype does not concern only population sizes and trends. Consider the following statement: "extirpation of loggerheads from X'cacel would eradicate 30% of the mtDNA diversity in Atlantic populations (Encalada et al. 1999)." But the samples on which the 30% figure is based came not only from X'cacel but from both there and Cozumel (Encalada et al. 1999). Because haplotype frequencies were not significantly different between these two places, the samples were pooled. So if there were no significant differences, even if X'cacel were paved over with solid concrete, some of the genetic diversity would be preserved by turtles nesting on Cozumel. One wonders how many of the 3 unique haplotypes found in this study were represented in Cozumel nesters.

Another caution about accepting that 30% of the mtDNA diversity would go down if X'cacel were destroyed is that loggerheads (Caretta caretta) also nest at Guanacabibes and the Isle of Pines in Cuba. For a turtle, these places are not at all far from the Yucatan. Until data from such nearby places are available, some caution about genetic diversity is in order.

It is heartening to learn that the threat to X'cacel has been repulsed, because there are plenty of valid reasons for looking after the turtles there. But is it really essential to concoct biodiversity hype to make the case? Presumably the reason is that hype provides some short-term gains in fund raising and activating campaigns. But there is also a downside.

Figure 1. Index of green turtle nesting at Raine Island, Australia. (Data from Table 1 in Limpus and Nicholls 2000). Values for 1974 are not given in this table, but the legend of Fig 1 indicates that although not graphed there, large numbers were nesting that season. However, even if a value of 11,000 were included for 1974, there is still no downward trend.

Negative consequences of hype. As well as any short-term tactical gains, the potential damage caused by hype must be considered. How can sound conservation and management proceed, and priorities be appropriately set, if people do not have as accurate information as possible on the biological situation? Also, telling people that species are facing a high risk of extinction in the near or immediate future when manifestly this is not so undermines IUCN and its red lists. It undermines the credibility of those who promulgate such views. Sooner or later, the "truth will come to light."

Perhaps worse are the insidious consequences of enveloping conservation biology in exaggeration and unsubstantiated assertions. It encourages people entering the field to think it is the norm to automatically and uncritically say a species is on the brink of extinction. When their mentors, supervisors, and seniors are putting such statements in their grant proposals and pamphlets to the public, it becomes the accepted practice. Hype perniciously downgrades precisely what one should wish to encourage in scientists: an overriding respect for the truth. Hype corrupts.

Of course, the inspiration for conservation does not come only from scientific considerations. Some people have religious or other grounds for wanting no turtles killed (cf Pritchard 2000). Many biologists would probably find it acceptable that some people wish to make the eating of turtles a taboo in their culture provided they do not try to force their views on other cultures. If people place greater moral disapproval on killing a turtle than killing a fish, that is their prerogative. But the scientific aspects of conservation if they are to be truly scientific must necessarily stand outside personal values. Their authentication comes from providing as far as is possible a truthful representation or explanation of the facts. Therefore, if biological considerations are brought into the reasons for conserving turtles, we must strive as much as possible to make the science accurate, and to resist alarmist statements that ignore obvious facts, such as that on some beaches turtles are nesting in densities so great as to result in them digging up thousands of eggs of those that nested before.

Most turtle biologists if they were being dispassionate would accept, I believe, that some sea turtle populations are in a dire predicament, but that others are holding their own or even increasing. They would have to accept this, because that is the truth of the matter, however much some may try to conceal this from the public.

Separation of assessment and action. To the extent we want a scientifically based conservation, we should start with the facts. As Mace and Lande (people who have been prominent in the development of the red listing system) put it in 1991:

Figure 2. Number of olive ridley nests laid in Sergipe (data from Marcovaldi 2001). The values have been read off a graph and are therefore approximate. However, the trend is also up using nonparametric statistics (p<.0001, Spearman's rho = .98). The data for the 1998/99 season have been excluded because "the monitoring effort was reduced" then. This implies that monitoring was reasonably standard in the other years, and the paper mentions that "regular monitoring was begun in 1982." The Spanish version uses the word "sistemático". Should some of the changes reported be attributable to changes in monitoring, then even though the value of this work would be diminished, the discrepancy between what the text says and the graph shows would still stand as a classic example of hype of the understatement variety.

It is important to distinguish systems for assessing threats of extinction from systems designed to help set priorities for action. The categories of threat should simply provide an assessment of the likelihood that if current circumstances prevail the species will go extinct within a given period of time. This should be a scientific assessment, which ideally should be completely objective. In contrast, a system for setting priorities for action will include the likelihood of extinction, but will also embrace numerous other factors, such as the likelihood that restorative action will be successful; economic, political, and logistical considerations; and perhaps the taxonomic distinctiveness of the species under review.

To this list one might add the charisma or huggability of a species, personal preferences and ethics, and religious beliefs. But if such considerations are to be allowed to override a scientific assessment of survival prospects, then and this is the essential plea of this article lets give up the pretence of being concerned about the biology and the actual risk of extinction, and discuss only why one might want to conserve turtles. If it stems from some overriding ethical conviction, lets be open about that; there is room for diversity.

But if such convictions are wrapped in pseudo science and hype, then others may legitimately object. Those others should include all who are trying to get the facts straight, trying to understand the biology despite the gaps in information and the intrinsic difficulties of sea turtle demography, and all those who value the assessment stage of Mace and Lande's programme.

That objections are so few makes one think that most sea turtle conservationists are happy with the hype and unconcerned with scientific substantiation or are too intimidated to voice their opinions. When can we stop pretending? Most sea turtle species are not on the brink of extinction, but some populations are. Let's start with the facts, and base our actions accordingly (Mrosovsky 1983).

BASINTAL, P. & M. LAKIM. 1994. Population status and management of sea turtles at the Sabah Turtle Island Park. In: A. Nacu, R. Trono, J.A. Palma, D. Torres and F. Agas (Eds.). Proceedings of the First Asean Symposium-Workshop on Marine Turtle Conservation, Manila, Philippines. World Wildlife Fund 1994. pp. 139-149.

BJORNDAL, K.A., J.A. WETHERALL, A.B. BOLTEN & J.A. MORTIMER. 1999. Twenty-six years of green turtle nesting at Tortuguero, Costa Rica: an encouraging trend. Conservation Biology 13:126-134.

ENCALADA, S.E., J.C. ZURITA & B.W. BOWEN. 1999. Genetic consequences of coastal development: the sea turtle rookeries at X'cacel, Mexico. Marine Turtle Newsletter 83:8-10.

GODREY, M.H. 1997. Further scrutiny of Mexican ridley population trends. Marine Turtle Newsletter 76:17-18.

JESSOP, T.S., C.J. LIMPUS & J.M. WHITTIER. 1999. Plasma steroid interactions during high-density green turtle nesting and associated disturbance. General and Comparative Endocrinology 115:90-100.

LIMPUS, C. & N. NICHOLLS. 2000. ENSO regulation of Indo-Pacific green turtle populations. In: G.L. Hammer et al.. (Eds.). The Australian Experience. Kluwer Academic Publishers, Netherlands. pp. 399-408.

MACE, G.M. & R. LANDE. 1990. Assessing extinction threats: Toward a reevaluation of IUCN threatened species categories. Conservation Biology 5:148-157.

MARCOVALDI, N. 2001. Status and distribution of the olive ridley turtle, Lepidochelys olivacea, in the Western Atlantic Ocean. In: K.L. Eckert and F.A. Abreu Grobois (Eds.). Proceedings of the Regional Meeting: "Marine Turtle Conservation in the Wider Caribbean Region: A Dialogue for Effective Regional Management", Santo Domingo, 16-18 November 1999. WIDECAST, IUCN-MTSG, WWF and UNEP-CEP. pp. 54-58.

MORTIMER, J.A. 1998. Turtle and tortoise conservation. Project J1, Environmental Management Plan of the Seychelles, Final Report, Volume 1. Ministry of Environment, Republic of Seychelles. 82 pp.

MROSOVSKY, N. 1983. Conserving Sea Turtles. British Herpetological Society, London. 177pp.

MROSOVSKY, N. 2000. Sustainable Use of Hawksbill Turtles: Contemporary Issues in Conservation. Key Centre for Tropical Wildlife Management. Northern Territory University, Darwin.

MUSICK, J. 2000. Cturtle 7, Dec. 2000.

PRITCHARD, P.C.H. 1997. A new interpretation of Mexican ridley population trends. Marine Turtle Newsletter 76:14-17.

PRITCHARD, P.C.H. 2000. A response to Nicholas Mrosovsky?s Sustainable Use of Hawksbill Turtles: Contemporary Issues in Conservation. Chelonian Conservation Biology 3:761-767.

RAINE ISLAND CORPORATION. 1985. 4^th Annual Report 1984-85. Queensland, Australia. 19 pp.

¹ Hype, short for hyperbole, excess, exaggeration