Density-dependent growth in hatchery-reared brown trout released into a natural stream

• Hatchery-reared brown trout Salmo trutta stocked in a natural stream in addition to resident wild brown trout grew more slowly than those stocked with an experimentally reduced density of brown wild trout. In both cases, hatchery-reared brown trout grew more slowly than resident wild fish in control sections. Mortality and movements did not differ among the three categories of fish. The results showed that growth of stocked hatchery-reared brown trout parr was density-dependent, most likely as a consequence of increased competition. Thus, supplementary release of hatchery-reared fish did not necessarily increase biomass. (C) 2004 The Fisheries Society of the British Isles.

Subject headings

NATURVETENSKAP  -- Biologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences (hsv//eng)

Keyword

density-dependence

enhancement

growth

hatchery

movement

stocking

salmo-trutta l

body-size

territorial contests

rearing environment

prior residence

wild

competition

stocking

skills

fish

Publication and Content Type

ref (subject category)

art (subject category)