Anguilla anguilla

  • Scientific name

    • Anguilla anguilla (Linnaeus, 1758)

  • Common name

    • European eel

  • Family

    • Anguillidae

  • External links

    • Fishbase
Trait completeness 84%
Total data159
References33
Image of Anguilla anguilla

Author: Fabrice Téletchéa
License: All rights reserved

Traits detail

Egg (100.0%)

Trait id Trait Primary data Secondary Data References
1 Oocyte diameter 1.2 1.2 mm Deelder, 1970
1 Oocyte diameter Eggs diameters are relatively uniform 1.05 ± 0.15 [Some discrepancy exists between different authors as to size of the European eel egg: 0.93-1.4; 1.0-1.1; 1.2-1.6; 0.9-1.1.3 mm] 1.05 mm Boetius and Boetius, 1980
1 Oocyte diameter Eggs of 1.0-1.3 mm in diameter have been considered to be fully ripened 1.15 mm Epler et al, 1981
1 Oocyte diameter Average diameter: 1.15 1.15 mm Bruslé and Quignard, 2001
1 Oocyte diameter 1.1-1.2 [Seems to be fertilized eggs] 1.15 mm Bonislawska et al, 2001
1 Oocyte diameter 1-1.4 [Unfertilized eggs] 1.2 mm Pedersen, 2003
1 Oocyte diameter 0.829-0.924 [Ovulated egg] 0.88 mm Pedersen, 2004
1 Oocyte diameter 0.8-0.95 [Stripped oocytes] 0.88 mm Palstra et al, 2005
1 Oocyte diameter Transparent ripe eggs with average diameter of 1.2 ± 0.06 1.2 mm Amin, 1998
1 Oocyte diameter Mode 1.14, range 0.9-1.38 1.14 mm Fishbase, 2006
1 Oocyte diameter 1.2 1.2 mm Coad, 2005
2 Egg size after water-hardening 2.3-2.9 [Swollen eggs] 2.6 mm Deelder, 1970
2 Egg size after water-hardening Eel eggs during further development will swell to diameters of 2.3 to 2.9 mm 2.9 mm Boetius and Boetius, 1980
2 Egg size after water-hardening Swelling of the eggs completes after 1.5 hour, the diameter of swollen eggs is 1.1-1.2 mm 1.15 mm Prokhorchik et al, 1988
2 Egg size after water-hardening About 2 mm after fertilization 2.0 mm Bruslé and Quignard, 2001
3 Egg Buoyancy Pelagic Pelagic Deelder, 1970
3 Egg Buoyancy In sea water of 31 °/oo all eggs sink Demersal Boetius and Boetius, 1980
3 Egg Buoyancy Under experimental conditions, the fertilized eggs rose toward the surface in a salinity of 35%o [The large fat drop ensures egg buyoancy] No category Prokhorchik et al, 1988
3 Egg Buoyancy Newly fertilized eggs were at or near the surface Pelagic Pedersen, 2003
3 Egg Buoyancy More than 90% of the eggs from all different batches floated Pelagic Palstra et al, 2005
3 Egg Buoyancy Pelagic Pelagic Coad, 2005
3 Egg Buoyancy Buoyant (Pelagic) Pelagic Fishbase, 2006
3 Egg Buoyancy Pelagic eggs Pelagic Vincent et al, 2005
4 Egg adhesiveness Not sticky Non-Adhesive Palstra et al, 2005
4 Egg adhesiveness Not sticky Non-Adhesive Fishbase, 2006
4 Egg adhesiveness Non-sticky Non-Adhesive Vincent et al, 2005
5 Incubation time 2-3.3 [Mass hatching occurred after 50-80 hours, being completed after 70-110 hours] 2.65 days Prokhorchik et al, 1988
5 Incubation time 2-4.5 (mean 2.5) 3.25 days Lecomte-finiger. Bull.Fr. Pêche Pisci. (1994) 335 : 17-31
5 Incubation time 2-5 [Mass hatching after about 50-60h, range 47-120 [5 days at 20, but "the surviving embryos had a delayed hatch on day 5 after fertilisation"] 3.5 days Pedersen, 2003
5 Incubation time 2 [48 hour] 2.0 days Pedersen, 2004
6 Temperature for incubation Incubated at 21-23°C 22.0 °C Boetius and Boetius, 1980
6 Temperature for incubation 20 20.0 °C Pedersen, 2003
6 Temperature for incubation 20 20.0 °C Palstra et al, 2005
6 Temperature for incubation 20-21 20.5 °C Pedersen, 2004
6 Temperature for incubation Incubated at 23°C 23.0 °C Amin, 1998
7 Degree-days for incubation Certainly about 40-50 45.0 °C * day Pedersen, 2003
7 Degree-days for incubation About 40 40.0 °C * day Pedersen, 2004

Larvae (71.0%)

Trait id Trait Primary Data Secondary Data References
8 Initial larval size The prolarvae are 2.5-2.7 mm in the period of mass hatching 2.6 mm Prokhorchik, 1987
8 Initial larval size 2.7 2.7 mm Prokhorchik et al, 1988
8 Initial larval size 2.5-2.7 2.6 mm Lecomte-finiger. Bull.Fr. Pêche Pisci. (1994) 335 : 17-31
8 Initial larval size 2.9 2.9 mm Bruslé and Quignard, 2001
9 Larvae behaviour Pelagic Pelagic Spilmann, 1961
9 Larvae behaviour Pelagic Pelagic Deelder, 1970
9 Larvae behaviour The prolarvae on hatching settled at the bottom of the incubation containers and remained lying with the back down, periodically making spiral movements and rising into the water column. The large fat droplet, broad fin border and head sinus ensured buoyancy of the prolarvae Demersal Prokhorchik, 1987
9 Larvae behaviour Pelagic Pelagic Bruslé and Quignard, 2001
11 Temperature during larval development About 20 20.0 °C Deelder, 1970
11 Temperature during larval development The smallest (probably just hatched) larvae were found at depths between 50 and 300 m with temperatures of 18-24°C respectively 21.0 °C Vincent et al, 2005
12 Sibling intracohort cannibalism Present Present Hecht and Pienaar, 1993
12 Sibling intracohort cannibalism A RELIRE :!!! Absent Degani & Levanon 1983
13 Full yolk-sac resorption After four days, the yok sac is almost completely resorbed, the fat doplet begins to resorb No data Prokhorchik, 1987

Female (92.0%)

Trait id Trait Primary Data Secondary Data References
15 Age at sexual maturity 10-18 14.0 year Spillmann, 1961
15 Age at sexual maturity Mean age about 7, range 3.4-12.3, means in various locations 7.85 year Vollestad and Jonsson, 1986
15 Age at sexual maturity 12-18, means in different areas 15.0 year Svedäng et al, 1996
15 Age at sexual maturity 3-12 [Female] 7.5 year Bruslé and Quignard, 2001
15 Age at sexual maturity 8-9 [France], 15-18 [Germany], female 8.5 year Fishbase, 2006
15 Age at sexual maturity Age at maturity is highly variable, ranging from 6 to 50 years in females over a latitudinal gradient. In Northern Europe the mean age at maturity of females can range from 12 to 20 years (or older), while in Southern Europe it is 6-8 years 7.0 year Vincent et al, 2005
16 Length at sexual maturity 40-100 70.0 cm Spillmann, 1961
16 Length at sexual maturity > 45 [Female] 45.0 cm Deelder, 1970
16 Length at sexual maturity Gonadal sex differentiation in the >European eel is ot age dependent but seems to be partly correlated with body length and begins when the eels reach 14-35 cm in length 24.5 cm Bieniarz et al, 1981
16 Length at sexual maturity Mean 61, range 39.0-105 [Female, n=1145] 72.0 cm Vollestad and Jonsson, 1986
16 Length at sexual maturity Means of 60.2-86.8, in various areas 73.5 cm Svedäng et al, 1996
16 Length at sexual maturity Female silver: mean 63.10 ± 1.22, range 53.10-79.50 63.1 cm Beullens et al, 1997
16 Length at sexual maturity 45-50 [Female] 47.5 cm Bruslé and Quignard, 2001
16 Length at sexual maturity Metamorphosis occurred between 40-75 cm 57.5 cm Acou et al, 2003
16 Length at sexual maturity Usually begin to mature at 54 cm to longer [38-130, silver age, female] 84.0 cm Coad, 2005
16 Length at sexual maturity 60 [Unsexed] 60.0 cm Fishbase, 2006
16 Length at sexual maturity Females mature at a size of > 60 cm 60.0 cm Vincent et al, 2005
17 Weight at sexual maturity Body weight of eels at catch averaged 0.8 Kg (range 0.5 to 1.5 kg) 0.8 kg Boetius and Boetius, 1980
17 Weight at sexual maturity Mean 0.425, range 0.130-2.105 [Female, n=1145] 1.12 kg Vollestad and Jonsson, 1986
17 Weight at sexual maturity Mean of 0.343-1.242, in various areas 0.79 kg Svedäng et al, 1996
17 Weight at sexual maturity Female silver: mean 0.58 ± 0.03, range 30.9-83.0 0.58 kg Beullens et al, 1997
18 Female sexual dimorphism Females are larger than males Absent Vollestad and Jonsson, 1986
19 Relative fecundity 3000 3000.0 thousand eggs/kg Deelder, 1970
19 Relative fecundity The data in the present paper can be converted to average 1.6 million/kg, which is about half of the Russian figure 1.6 thousand eggs/kg Boetius and Boetius, 1980
19 Relative fecundity 700-2600 up to 3000 1650.0 thousand eggs/kg Bruslé and Quignard, 2001
19 Relative fecundity 3000 3000.0 thousand eggs/kg Coad, 2005
20 Absolute fecundity The estimated fecundity of matured eels ranged from 0.7 to 2.6 million eggs [For immature eel the US authors give records of European specimens having 5-10 millions eggs on average with 15-20 million for the largest specimens] 7.5 thousand eggs Boetius and Boetius, 1980
20 Absolute fecundity Up to 4 000 4.0 thousand eggs Palstra et al, 2005
20 Absolute fecundity The absolute fecundity amounted 1.48 millions eggs 1.48 thousand eggs Amin, 1998
21 Oocyte development Synchronous Synchronous Rinchard, 1996
22 Onset of oogenesis Only after the fish begin their migration does further growth and development of gonads and oocytes take place , GSI at about 1.0-1.6 No data Bezdenezhinykh and Petukhov, 1982
24 Maximum GSI value Maximum GSI obtained in different studies: 12.6 only, 40 in other previous experiment and 60.7. 12.6 percent Boetius and Boetius, 1980
24 Maximum GSI value Reach 43.8-57.9 before spawning 50.85 percent Bezdenezhinykh and Petukhov, 1982
24 Maximum GSI value About 50% in artificial conditions 50.0 percent Vollestad and Jonsson, 1986
24 Maximum GSI value Up to 32 to 60% in artificial conditions ! 32.0 percent Bruslé and Quignard, 2001
24 Maximum GSI value 31.8 in artificial conditions 31.8 percent Pedersen, 2003
24 Maximum GSI value GSI of 44.8 ± 6.5 (range 36.3-60.0) in artificial conditions 44.8 percent Palstra et al, 2005
24 Maximum GSI value GSI of 68.4% 68.4 percent Amin, 1998
24 Maximum GSI value GSI equalled from 35.1 to 42.3 35.1 percent Epler et al, 1981
25 Oogenesis duration Under artificial conditions, maturation of females took 5-6 months 5.5 months Pedersen, 2003
26 Resting period About 0.6 ± 0.28 for the yellow stage and 1.78 ± for the silver stage 0.6 months Acou et al, 2003
26 Resting period > 1.4% for the silver stage 1.4 months Marchelidon et al, 1999

Male (56.0%)

Trait id Trait Primary Data Secondary Data References
27 Age at sexual maturity 8-15 11.5 years Spillmann, 1961
27 Age at sexual maturity 5 [France], 9-13 [Germany], male 11.0 years Fishbase, 2006
27 Age at sexual maturity 2.5-5 [Male] 3.75 years Bruslé and Quignard, 2001
27 Age at sexual maturity Mean age about 5, range 2.5-9.1, means in various locations 5.8 years Vollestad and Jonsson, 1986
27 Age at sexual maturity Males tend to mature at and age of 3-4 years 3.5 years Vincent et al, 2005
28 Length at sexual maturity 20-50 35.0 cm Spillmann, 1961
28 Length at sexual maturity 29-40 [Silver age] 34.5 cm Coad, 2005
28 Length at sexual maturity 60 [Unsexed] 60.0 cm Fishbase, 2006
28 Length at sexual maturity < 45 [Male] 45.0 cm Deelder, 1970
28 Length at sexual maturity 30-45 [Male] 37.5 cm Bruslé and Quignard, 2001
28 Length at sexual maturity Mean 41, range 32.5-45 [Female, n=75] 38.75 cm Vollestad and Jonsson, 1986
28 Length at sexual maturity On average less than 45-50 cm 47.5 cm Colombo and Grandi, 1996
28 Length at sexual maturity Male silver: mean 42.03 ± 0.29, range 35.10-58.20 42.03 cm Beullens et al, 1997
28 Length at sexual maturity Male silver eels about 38 cm were brought to the laboratory 38.0 cm Boetius and Boetius, 1980
28 Length at sexual maturity Males tend to mature at a size of around 40 cm 40.0 cm Vincent et al, 2005
29 Weight at sexual maturity Mean 0.107, range 0.028-0.162 [Female, n=75] 0.1 kg Vollestad and Jonsson, 1986
29 Weight at sexual maturity Male silver: mean 0.168 ± 0.004, range 0.077-0.409 0.17 kg Beullens et al, 1997
29 Weight at sexual maturity Male silver eels about 80 g were brought to the laboratory 80.0 kg Boetius and Boetius, 1980
33 Maximum GSI value Gonad weight of mature males only constitutes, at most 14% of the body weight 14.0 percent Vollestad and Jonsson, 1986
33 Maximum GSI value 9.0 ± 1.10% coincide with the onset of spawning migration (treated males) 9.0 percent Amin, 1998
35 Resting period About 0.1 for the silver stage 0.1 months Marchelidon et al, 1999

Spawning conditions (93.0%)

Trait id Trait Primary Data Secondary Data References
36 Spawning migration distance Distance of 5000-6000 km is covered by mature adult 5500.0 km Fishbase, 2006
36 Spawning migration distance Spawning phase to reach the Sargasso Sea 7000 km from Europe 7000.0 km Coad, 2005
36 Spawning migration distance 6000-8000 km 7000.0 km Bruslé and Quignard, 2001
37 Spawning migration period In France in fall: October to December ['October', 'November', 'December'] Bruslé and Quignard, 2001
37 Spawning migration period Spawning migration that extend from November to February ['January', 'February', 'November'] Amin, 1998
37 Spawning migration period The mature silver eel leaves the rivers of Europe and North Africa in the autumn and swims accross the North Atlantic Ocean (navigating by an unknown process) to spawn in the Sargasso sea in the first half of the following year. Although the spawning process has never been observed, the small eel larvae (leptocephali) appear in the Sargasso Sea between February and July and drift on the ocean currents ['February', 'March', 'April', 'May', 'June', 'July', 'October', 'November', 'December'] Keetle and Haines, 2006
39 Spawning season January-July ['January', 'July'] McCleave J.D.. R.C. Kleckner and M. Castonguay. 1987. American Fisheries Society Symposium. 1: 286-297.
39 Spawning season March until May [Also January-February] ['January', 'February', 'March', 'April', 'May'] Fishbase, 2006
39 Spawning season Spawning takes place at the beginning of March ['March'] Coad, 2005
39 Spawning season During winter ['January', 'February', 'March'] Deelder, 1970
39 Spawning season November-July, peaking in January ['January', 'July', 'November'] Wang and Tzeng, 2000
39 Spawning season Based on all these observations, we now know that the European eel spawn primarily from March to June within a narrow ellipse whose long axis extends east-west from approximately 48° to 74°W longitude between 23° and 30° N latitude ['March', 'April', 'May', 'June'] Vincent et al, 2005
40 Spawning period duration Lengthly spawning season No data Wang and Tzeng, 2000
40 Spawning period duration Reproduction from February to April or March to July No data Bruslé and Quignard, 2001
41 Spawning temperature 17.0 17.0 °C Coad, 2005
41 Spawning temperature About 20 20.0 °C Deelder, 1970
41 Spawning temperature 16-17 16.5 °C Bruslé and Quignard, 2001
41 Spawning temperature Water temperature ranged from 20 to 24°C 20.0 °C Amin, 1998
41 Spawning temperature Releasing hormone treated mature female adults tagged with radio transmitters in the Sargasso Sea demonstrated a preference for the upper zone of the ocean at depths of 18.7-18.8°C 18.75 °C Vincent et al, 2005
42 Spawning water type Sargasso Sea No category Deelder, 1970
42 Spawning water type Sargasso Sea [Larvae hatch in region with low current] Flowing or turbulent water Bruslé and Quignard, 2001
42 Spawning water type Sargasso sea No category Vollestad and Jonsson, 1986
42 Spawning water type Fish spawning out of the tributary area: carp, pikeperch, catfish Silurus glanis and eel No category Hladik and Kubecka, 2003
43 Spawning depth Spawning grounds are about 400 meters 400.0 m Coad, 2005
43 Spawning depth Around 100-200 m deep 150.0 m Deelder, 1970
43 Spawning depth Spawning probably occurs at great depths No data Vollestad and Jonsson, 1986
43 Spawning depth Releasing hormone treated mature female adults tagged with radio transmitters in the Sargasso Sea demonstrated a preference for the upper zone of the ocean at depths of 250-270 m 260.0 m Vincent et al, 2005
44 Spawning substrate Pelagophilous Pelagophils Balon, 1975
44 Spawning substrate Pelagophilous Pelagophils Boetius and Boetius, 1980
45 Spawning site preparation Open water/substratum egg scatterers Open water/substratum scatter Fishbase, 2006
45 Spawning site preparation Open substratum spawner Open water/substratum scatter Balon, 1975
46 Nycthemeral period of oviposition Only a few of our eels were direclty observed to spawn a significant amount of eggs. But no doubt several other eels at intervals (especially by night) have releaseed small amount of eggs Night Boetius and Boetius, 1980
47 Mating system Under articificial conditions, eels are promiscuous Promiscuity Coad, 2005
47 Mating system In articificial conditions, apparently promiscuous Promiscuity Deelder, 1970
47 Mating system The number of participating males was 1-3 per female. During the first 15 minutes or so the male will swim around as if he were searching for someting while the female will remain almost quiet. When finally the male has detected the female he starts rubbing her belly with his head. He is especially attracted by her abdominal apertures. The female is thereby pushed slowly forwards through the water and starts a slow swimming. Still while the couple is moving, the stimulated male will try to obtain maximum contact between the bodies and is often seen to cling on the female with his back against her belly. When two or three males were placed together with one female they all tok part in the initial courtship. In every case, however, only one of the participating males released sperm during the experiment No category Boetius and Boetius, 1980
47 Mating system Mating began with the males which gently touched the females very often, followed by moving together with bodies in contact near the surface No category Amin, 1998
48 Spawning release Total spawner, only once Total Rinchard, 1996
48 Spawning release It seems that female eel undergoing artificial maturation function as batch spawners Multiple Pedersen, 2003
48 Spawning release Each female probably spawns intermittently with several males each time Multiple Vollestad and Jonsson, 1986
48 Spawning release Most eels ovulated more than once over periods up to several days Multiple Palstra et al, 2005
49 Parity Semelparous Semelparous Rinchard, 1996
49 Parity Mirgating to sea to spawn and die Semelparous Coad, 2005
49 Parity Spawing once and die Semelparous Palstra et al, 2005
49 Parity Spawn and then die Semelparous Vincent et al, 2005
50 Parental care Nonguarders No care Fishbase, 2006
50 Parental care The parents showed absence of parental care so their behaviour can be classified as non-guarding No care Vincent et al, 2005