Suppliers of Glass Eels for Farming and Restocking

Developing a

Sustainable Fishery

Is this species critically endangered?

For full IUCN statement click here

The IUCN statement is factually incorrect . There are weaknesses, inconsistencies and errors in the case made by the IUCN that the European eel is critically endangered. It would appear that this judgement seems to have been reached by only a few people, without any detailed scientific peer review of the citation. There is a real risk that this ruling could lead to inappropriate management actions.

News

IUCN “To Be or Not To Be” critically endangered?

Our organisations objective is to promote the sustainable management of the eel by working with both the aquaculture industry and with the EU Commission to implement the national and river basin eel recovery plans. . There are some major misconceptions about the declines in recruitment in the European eel since the 1980s, with erroneous statements being made such as “stocks have shown unprecedented falls throughout Europe by 99%'”and” the species is near to extinction”’ and” it is being destroyed by pollution parasites and viral infections infections”. It us very import that a balanced perception of the issues involved reaches the public domain if inappropriate management actions are to be avoided .

A.anguilla

COMMENTS ON IUCN RED LIST OF THREATENED SPECIES CITATION FOR ANGUILLA ANGUILLA (L.) February 2009
Dr Brian Knights MSc, PhD, CBiol, FIBiol, CEnv, FIFM

Ref: Freyhof, J. & Kottelat, M. 2008. Anguilla anguilla. In: IUCN 2008. 2008 IUCN Red List of Threatened Species. http://www.iucnredlist.org/details/60344

Summary

There are important errors, omissions and contradictions in this document that severely weaken the case made that the European eel is ‘critically endangered’.

A. lack of consideration of data available for stocks in NW Europe

B. incorrect assumption that a reconstructed time series of commercial FAO landings since the 1960s is a direct proxy for all European-N African stocks.

C. lack of consideration of pre-1980 data, leading to assumptions that recruitment and stock are at ‘historic lows’

D. lack of consideration of recent and historical regime shifts, indicative of major wide-scale shifts in ocean-climate and biology.

E. over-estimation that average age-at-maturity throughout the European eel’s range is ~20 years and that declines and ‘recovery’ take many decades

F. incorrect assumption that there is a clear relationship between measures of stocks and recruitment

G. lack of consideration of similar changes in recruitment in the American and Japanese eel and probable causes – and that the American eel has formally been judged as not endangered

H. lack of consideration of evidence that (natural) oceanic factors are of major importance – and that eels have survived major oceanic and continental environmental changes over millions of years

SPECIFIC COMMENTS ON THE TEXT

Taxonomic Notes:

1. Even from natural stocks. This statement is meaningless.

Justification:

2. The species has undergone a sharp decline in both recruitment and yield and stock Analyses of 54 stock data sets from NW Europe post-1970 show that only 35% have declined significantly (Knights & Bonhommeau, 2008). Time series (N = 31) indicate that stock levels were relatively low in the early-1970s but increased to peaks in the early-1980s in N Atlantic and North Sea sites, such that current stock levels appear similar to those in the early-1970s. Of stock data sets showing a significant decline, the majority (74%) only cover the period of decline that followed the peaks in the early-1980s.

3. An historical time series for the Skagerrak (Norway) shows similar recent changes but also that stocks were as low or lower in the 1920s as in recent years (Durif et al., 2008)

4. Recruitment of glass eels has declined since 1980 and since 2000 is at an historical low at just 1-5% of the pre-1980 levels. Recruitment has declined from peak levels around 1980 but the term at an historical low needs qualifying because 21 time series stretching as far back as the early-1900s show that recruitment has fluctuated widely over decadal time scales (Knights & Bonhommeau, 2008). Recruitment showed relatively large peaks in the early-1980s and in previous decades, but was relatively low in the 1970s and, very probably, in the early 1900s.

5. and since 2000 [recruitment] is at an historical low at just 1-5% of the pre-1980 levels. Glass eel recruitment has declined since peak levels in the early-1980s to ~1% in North Sea sites and by ~10% in N Atlantic sites

6. Yield and stock abundance has declined since the 1960s. This statement is based on the assumption that reconstructed FAO landings are a proxy for stocks. However, there is no specific evidence for a range-wide decline in stocks over this time scale, except in Baltic Sea sites concurrent with declines in recruitment, largely of juvenile yellow eels (Knights & Bonhommeau, 2008).

7. As the recruitment rate is so low the population is continuing to decline as older eels disappear from the stock. Relationships between recruitment and stocks are too unclear to make such a definitive statement for the whole species.