A member of the herring family, shad is also known as river herring, because it swims up the rivers to spawn—the Ardour, Garonne, Dordogne and Isle are its most important habitats in Europe, although today is it endangered.
There are two kinds, the grande alose (or allis shad, Alosa alosa) and the smaller alose feinte (or twaite shad, Alosa fallax fallax). The French often serve them with sorrel (alose à l'oseille).
Image by Hans Hillewaert, Creative Commons License