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The lesser sand eel or sand lance (''Ammodytes tobianus'') is a
species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of
fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...
in the sand lance
family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Ammodytidae. It is an elongated cylindrical fish which may be up to long.


Description

The body of the lesser sand eel has an elongated shape with a rounded cross section. The head is also elongated and pointed, and the sharp prominent lower
jaw The jaw is any opposable articulated structure at the entrance of the mouth, typically used for grasping and manipulating food. The term ''jaws'' is also broadly applied to the whole of the structures constituting the vault of the mouth and serv ...
projects further than the upper jaw. When the mouth is opened, the two jaws form a tube through which food is sucked in. The top of the fish's mouth lacks
teeth A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, tear ...
. The
scales Scale or scales may refer to: Mathematics * Scale (descriptive set theory), an object defined on a set of points * Scale (ratio), the ratio of a linear dimension of a model to the corresponding dimension of the original * Scale factor, a number w ...
of the belly make a chevron pattern. The dorsal fin is long and ribbon-like, the pectoral fins are small and low set, and there are no
pelvic fins Pelvic fins or ventral fins are paired fins located on the ventral surface of fish. The paired pelvic fins are homologous to the hindlimbs of tetrapods. Structure and function Structure In actinopterygians, the pelvic fin consists of two en ...
. The
caudal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...
is bifurcated in shape. The skin color is greenish yellow on the back, yellowish on the upper sides, and a mixture of a brilliant
silver Silver is a chemical element with the Symbol (chemistry), symbol Ag (from the Latin ', derived from the Proto-Indo-European wikt:Reconstruction:Proto-Indo-European/h₂erǵ-, ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, whi ...
on the lower sides and belly. This fish can be distinguished from the greater sand eel by its smaller size (less than ) and the fact that the origin of the long dorsal fin starts approximately in line with the tip of the pectoral fin.


Behavior

Breeding Breeding is sexual reproduction that produces offspring, usually animals or plants. It can only occur between a male and a female animal or plant. Breeding may refer to: * Animal husbandry, through selected specimens such as dogs, horses, and rab ...
, can vary to which race they are native, and usually happens from February to April, or from September through into November. Adult forms become mature in 1 to 2 years (8 cm+), and will live 7 years or more. It habitates from mid-tide level below to around 30m in inshore waters, that have clean and sandy bottoms. It is commonly found swimming in huge
shoals In oceanography, geomorphology, and geoscience, a shoal is a natural submerged ridge, bank, or bar that consists of, or is covered by, sand or other unconsolidated material and rises from the bed of a body of water to near the surface. It o ...
and rapidly burrows in sand if alarmed. It is nocturnal, spending the day buried in the sand and emerging at dusk to feed. It eats
zooplankton Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by ...
, larvae of fish,
crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group ...
s, and other smaller invertebrates. In addition, it is found all throughout the coasts of the
British Isles The British Isles are a group of islands in the North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner and Outer Hebrides, the Northern Isles, ...
. Sand eels are an important part of the diet of many seabirds. Excessive fishing of sand eels on an industrial scale in the
North Sea The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian S ...
has been linked to a decline in the breeding success of kittiwakes, terns, fulmars and shags.


References


Bibliography



"The 2004 breeding season will go down as the worst in living memory for Fair Isle’s seabirds (Table 2). Numbers of birds attempting to breed were at their lowest levels for many species (Table 1) and very few chicks were seen. Common Guillemot, Razorbill, Black-legged Kittiwake, Arctic Skua, Arctic Tern and Common Tern all failed to fledge any young whilst just a single Great Skua fledged from a pitiful 96 AOT (Apparently Occupied Territories). As in most years of poor productivity, it is a lack of Lesser Sandeel (the staple diet of nearly all seabirds in Shetland) that is at the root of the problem." * Svenning, M.-A., Borgstrøm, R., Dehli, T.O., Moen, G., Pedersen, T., Barrett, R.T. & Vader, W. 2005. Large numbers of lesser sandeel (Ammodytes marinus) available as prey for marine fishes enhance the survival of Atlantic salmon smolts (Salmo salar) as they leave the Tana river, North Norway. - Fisheries Research 76: 466-474.
Fishmeal Production
{{Taxonbar, from=Q1536887 Ammodytidae Fish described in 1758 Taxa named by Carl Linnaeus ru:Песчанки (род рыб)