Teleostei (teleosts) > Clupeiformes
(Herrings) > Alosidae
Etymology: Alosa: Latin, alausa = a fish cited by Ausonius and Latin, halec = pickle, dealing with the Greek word hals = salt; it is also the old Saxon name for shad = "alli" ; 1591 (Ref. 45335).
More on author: Regan.
Environment: milieu / climate zone / depth range / distribution range
Marine; freshwater; brackish; pelagic-neritic; anadromous (Ref. 59043). Subtropical
Africa: along North African coasts of Mediterranean Sea from the Rif Peninsula in Morocco to northern Tunisia (Ref. 10538), also entering permanent rivers in Algeria and Tunisia (Ref. 10538, 59043). A landlocked population exists in Lake Ichkeul, Tunisia (Ref. 59043). In Europe, it is restricted to western Sardinia, Italy (Ref. 59043).
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 43.5 cm SL male/unsexed; (Ref. 10538); 50.0 cm SL (female)
Morphology | Morphometrics
soft rays: 20 - 25;
Vertebrae: 53 - 57. Diagnosis: This species is distinguished from other species of Alosa entering freshwater in the Mediterranean basin by: dorsal profile convex; 40-60 thin gill rakers in individuals larger than 200 mm standard length, with 25 to 38 on its lower part; and no teeth on palatine (Ref. 10538, 59043).
This species undertakes anadromous breeding migrations from the sea, where it spends most of its life, into the freshwater sections of rivers; it can also live permanently in brackish water (Ref. 10538). Males migrate upriver at 3-4 years, females at 4-5 years; it starts entering rivers when temperatures reach 14-18°C, mainly in May, and spawning commences when temperature rises above 20°C in May and June (Ref. 59043). The spawners return downstream immediately after spawning, but many die after spawning; most juveniles migrate to river mouth in first summer and remain at sea until they mature (Ref. 10538, 59043). Spawning occurs close to estuaries in fresh and brackish water (Ref. 59043).
In the marine and brackish water habitats, this shad consumes small fishes, such as species of Engraulis, Sardina, and Sardinella, and small benthic crustaceans, mainly isopods and amphipods (Ref. 10538).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Most juveniles migrate to river mouth in first summer and remain at sea until they mature. Males migrate upriver at 3-4 years, females at 4-5. They start entering rivers when temperatures reach 14-18°C, mainly in May to spawn when temperatures rises above 20°C. After spawning, spent individuals migrate back to sea, but many die before they do (Ref. 59043).
Kottelat, M. and J. Freyhof, 2007. Handbook of European freshwater fishes. Publications Kottelat, Cornol and Freyhof, Berlin. 646 pp. (Ref. 59043)
IUCN Red List Status (Ref. 126983)
Threat to humans
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82804
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00724 (0.00339 - 0.01546), b=3.07 (2.90 - 3.24), in cm total length, based on LWR estimates for this Genus-body shape (Ref. 93245
Trophic level (Ref. 69278
): 3.9 ±0.5 se; based on size and trophs of closest relatives
Resilience (Ref. 120179
): Medium, minimum population doubling time 1.4 - 4.4 years (Preliminary K or Fecundity.).
Fishing Vulnerability (Ref. 59153
): Moderate vulnerability (44 of 100).