12: Trout and Char of Central and Southern Europe and Northern Africa
Javier Lobón-Cerviá, Manu Esteve, Patrick Berrebi, Antonino Duchi, Massimo Lorenzoni, and Kyle A. Young
The area of central and southern Europe, the Mediterranean, and North Africa spans a wide range of climates from dry deserts to wet forests and temperate maritime to high alpine. The geologic diversity, glacial history, and long human history of the region have interacted with broad climatic gradients to shape the historical and current phylogeography of the region’s native trout and char. The current distributions and abundances of native species are determined in large part by their fundamental niches (i.e., clean, cold water with high dissolved oxygen). Brown Trout Salmo trutta are relatively common and widespread in the northern and mountainous areas of the region but occur in isolated headwater populations in the warmer southern areas of the region. These southern areas provided glacial refugia for salmonids and today harbor much of the region’s phylogenetic diversity. Despite relatively narrow ecological requirements in terms of water quality, native and invasive trout and char occur throughout the region’s rivers, lakes, estuaries, and coastal waters. Despite having only a single widely recognized native trout species, the region’s range of environments has produced a remarkable diversity of life histories ranging from dwarf, stunted, short and long-lived, small- and large-sized, stream-resident, lake-resident, fluvial potamodromous, adfluvial potamodromous, and anadromous (see Chapter 7).
Only one trout and one char are native to the region, Brown Trout and Alpine Char Salvelinus umbla. There are four currently recognized Brown Trout relatives from the Italian peninsula and Mediterranean islands—Salmo fibreni, S. carpio, S. cettii, and S. marmoratus—and a taxonomically complex and poorly studied group of Brown Trout relatives in Morocco and Algeria. Three nonnative species from North America (sensu International Union for Conservation of Nature [IUCN]) have been introduced and established naturalized populations: Rainbow Trout Oncorhynchus mykiss, Brook Trout Salvelinus fontinalis, and Lake Trout S. namaycush. This chapter summarizes the information available on the distribution, status, and management of these trout and char.