The IUCN/SSC Shark Specialist Group
Shark News 13: July 2001
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The 2000 IUCN Red List of Threatened Species:
Elasmobranch Update
Rachel Cavanagh and Sarah Fowler, Shark Specialist Group
What is the Red List?
The IUCN Red List is widely recognised as the most comprehensive, global approach for evaluating the conservation status of plant and animal species. It has no statutory force, but occupies a prominent role in guiding the conservation activities of governments, NGOs and scientific institutions. The current Red List Programme began when the Species Survival Commission launched an initiative to revise the listing system, in recognition of the need for a consistent and objective process to describe threatened species. A quantitative system of criteria for assigning species to Red List categories of threat was adopted by the IUCN in 1994.
Elasmobranchs and the Red List
One of the recent introductions to the Red List Programme was a call to improve the coverage of elasmobranchs, few of which had been assessed in the past (the 1996 Red List included just 32 species). In 1999, numerous members of the SSG prepared assessments for over 100 species. Co-Chair Sarah Fowler coordinated a consultation of the entire SSG membership in July 2000, during which assessments were finalised by consensus in preparation for publication of the 2000 Red List in October. The result is summarised below.
Elasmobranch assessments, 2000 Red List
The Red List Categories 2000 Red List Assessments
| EX |
Extinct |
0 |
| EW |
Extinct in the Wild |
0 |
| CR |
Critically Endangered |
3 |
| EN |
Endangered |
17 |
| VU |
Vulnerable |
19 |
| LR/cd |
Lower Risk/conservation dependent |
4 |
| LR/nt |
Lower Risk/near threatened |
35 |
| DD |
Data Deficient |
17 |
| LR/lc |
Lower Risk/least concern |
10 |
It is too early to attempt to draw any significant trends from the limited data available, although it is clear that long-lived species with low fecundity are especially at risk, and groups such as the sawfish (Pristis spp., see below) give particular cause for concern. There is an urgent need to review all chondrichthyan species to give a balanced overview of the state of knowledge of the whole group.
Endangered Elasmobranchs
Elasmobranchs identified as Critically Endangered, the most severe 'at risk' category, indicating that a species is "facing an extremely high risk of extinction in the wild in the immediate future" were:
- The largetooth sawfish Pristis perottetii: taken in (former) directed fisheries and extremely vulnerable to bycatch in virtually all fisheries throughout its Atlantic and Eastern Pacific range. Its status is known to be especially serious in parts of Central America, including Lake Nicaragua.
- The common sawfish Pristis pristis: it is thought that this species will become extinct without timely intervention.
- The Brazilian guitarfish Rhinobatus horkelii: its abundance has decreased by 96% over the ten years from 1984, when landings peaked, to 1994. The inshore nursery grounds of this species are heavily fished and it is quite likely that this endemic guitarfish could be driven to extinction in the foreseeable future.
Three other species are identified as Endangered globally, but Critically Endangered in parts of their range, these are the great-tooth (or freshwater) sawfish Pristis microdon (CR in SE Asia), the smalltooth (or wide) sawfish Pristis pectinata (CR in the North and Southwest Atlantic - see page 15) and the common skate Raja (Dipturus) batis (CR in shelf seas). In addition, the giant freshwater whipray Himantura chaophraya is classed as Vulnerable globally, but Critically Endangered in Thailand and probably other localities.
Seventeen species of elasmobranchs have been listed as Endangered, meaning the taxon is "facing a very high risk of extinction in the near future". These include the Ganges shark Glyphis gangeticus and the speartooth shark Glyphis glyphis, both of which seem to be confined to rivers, estuaries and coastal waters under significant development and exploitation pressures. This category also encompasses four other sawfish species. Another 19 are Vulnerable.
Seventeen of the species assessed so far are Data Deficient, meaning that appropriate data on their distribution and/or abundance is lacking. Indeed, a very large proportion of all chondrichthyan fish species is likely to fall within this category.
It is most sobering, however, to note that less than 10% of the species assessed were considered to be Lower Risk/least concern - the only category of assessment not listed on the Red List database and website because these species are considered not to be threatened or likely to become threatened in the foreseeable future.
Current and Future Red List Assessments
You can search for all current threatened and Data Deficient elasmobranch Red Listings on www.redlist.org.
To suggest changes to any of the current listings, please contact Rachel Cavanagh rachel@naturebureau.co.uk who will be coordinating the SSG consultation and discussions on future changes and additions. In addition, the IUCN has now requested that the SSG complete assessments of all chondrichthyan species by the end of 2003. If you are interested in undertaking assessments, please contact Rachel with details of the species you would be prepared to review.
The SSC Red List Programme Office has issued the timetable for submissions to the Red List. The CD-ROM and website will be updated annually, and an analysis of the data produced in hard copy every four to five years. Unless otherwise notified, the following schedule will apply every year:
30th April: deadline for any petitions against listings appearing in the previous edition of the IUCN Red List. Petitions may only be based on the Red List Criteria and accompanying documentation.
31st August: deadline for the submission of new assessments, corrections, new documentation, etc.
31st August: deadline for the submission of justifications from the parties in petitions cases, if the matter has not been resolved.
Mid-November: The Red List Standards Working Group and Petitions Subcommittee will meet by mid-November to discuss and decide on the outcome of any petitions. This decision will appear in the next issue of the Red List.
Early January: public launch of the Red List.
Further Information
The 2000 IUCN Red List is not available in printed format because of the very large number of species covered. It may, however, be consulted on the internet at http://www.redlist.org. Full details of the Red List Categories and Criteria are also provided at this site. For general Red List enquiries email redlist@ssc-uk.org.
A publication and CD of The IUCN SSC 2000 Red List of Threatened Species, compiled by Craig Hilton-Taylor, ISBN 2-8317-0564-9, is available from IUCN publications, fax +44 1223 277175, or email info@books.iucn.org.
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