Below are the answers I received from my question about the age of a 90.5 lb. gutted, 88.25 inch (224 cm) total length conger eel, Conger conger, caught off Guernsey, G.B. last Sunday. It is interesting to note the considerable difference in growth rates between Conger conger and Conger oceanicus.
I was unable to secure the otoliths from the eel because the eel was sent to a fish auction in France.
From Hood, Peter [[log in to unmask]]
I did my master's thesis on C. oceanicus. I don't know if you can relate any info I collected to your problem. The oldest fish I had was 13 yrs and was 106 cm long. I also calculated an length/weight relationship. It was ln WW= 3.46(ln TL)-8.26 (r2=0.95). Whole weight was in g and TL is in cm. My thesis can be found in the 1988 volume of Marine Biology (98:587-596). In addition, there is info on C. conger that might be useful for you in an article by Cau and Maconi (1984) - Marine Biology (81:147-151). I hope this info helps - Peter
From Ian Knutsen [[log in to unmask]]
I have only some general info to contribute with. Size in fish are more correlated with feeding history than dates. The conger eel generaly don't get older than 13 -14 years. They may by then have reached a length of 98 in (250 cm) and weigh 132 -143 lb (60 -65 kg). Only the females get this size, males seldom get longer than 39 in (100 cm). Large in size but young at hart - the conger eel matures 10 -13 year old and die after spawning.
From Marie-Joelle ROCHET [[log in to unmask]]
Von Bertalanffy growth parameters for Conger conger :
females males
Linfinity 228.8 cm 94.8 cm
K 0.068 0.270
t0 -2.4 y 0.787 y
From Flores-Hernandez D., 1990. Les pecheries de congre (Conger conger L.) dans le Mor Braz, Bretagne Sud. These de l'Universite d'Aix-Marseille II, 150 p.
Marie-Joelle ROCHET
Laboratoire MAERHA
(Mathematiques Appliquees a l'Exploitation
des Ressources Halieutiques et Aquacoles)
IFREMER
B.P. 21105
44311 NANTES CEDEX 03
FRANCE
Tel 33 2 40 37 41 21
Fax 33 2 40 37 40 75
From Dr Audrey Geffen [[log in to unmask]]
The growth rate you have cited seems to be the most commonly quoted statistic about this fish. At least three of the sources I checked also gave the same data: Conger in aquaria can attain 90lb (40.5kg) in 5 years. A. Wheeler in The Fishes of the British Isles & Northern Europe also states "third year fish may weigh 2-3lb (0.9-1.3kg)", but gives no source for this information. He also gives the British record rod-caught fish as 84lb (38.1kg), so a new record is now likely! However, older sources give larger weights for Conger conger in European waters (up to 160 lbs): Jenkins, Fishes of the British Isles 1925, p 275 Day: Fishes of Great Britain vol 2 1884
I thank you for your generous help providing the information.
Yours sincerely,
Richard Lord
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Guernsey, GY1 1BQ
Great Britain
Tel: 01481 700688
Fax: 01481 700699
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