Twait shad are silvery, sometimes with a bronzy tinge, and there are a distinctive row of six to ten large dark spot just behind the gill cover though these may fade when the fish is dead. The adult length is typically . The twait shad is found in most of Europe and all countries bordering the Mediterranean Sea. "Alosa fallax" has a similar lifecycle to "A. alosa" (allis shad). They are known to live in sympatry. Some studies have suggested "A. fallax" and "A. alosa" species can hybridize. They are anadromous species, like many other species in the genus "Alosa". However, some
European herring gull European herring gull The European herring gull ("Larus argentatus") is a large gull (up to long). One of the best known of all gulls along the shores of western Europe, it was once abundant. It breeds across Northern Europe, Western Europe, Central Europe, Eastern Europe, Scandinavia and the Baltic states. Some European herring gulls, especially those resident in colder areas, migrate further south in winter, but many are permanent residents, e.g. in Ireland, Britain, Iceland, or on the North Sea shores. European herring gulls have a varied diet, including fish, crustaceans and dead animals as well as some plants. While