Definition of parr in US English:



  • A young salmon (or trout) between the stages of fry and smolt, distinguished by dark rounded patches evenly spaced along its sides.

    • ‘Over the months, their development is monitored by ‘babysitters’ as the fish grow from fry into young fish called parr and pre-smolt.’
    • ‘Quantitative analysis of duty cycle shows a significant increase in duty cycle at each position between parr and smolts.’
    • ‘Salmon parr in the wild will naturally come across patches of substrate of similar color to the marble chips used in this experiment.’
    • ‘As they gain in size, they become parr, a stage which lasts until they make their way down to the sea, undergo various changes designed to fit them for life in salt water, and acquire a new name, smolts.’
    • ‘Within minutes of the accident, fish began to leap furiously over all its quiet little pools, and within an hour the river became a floating graveyard of brown trout and salmon parr, carrying its cargo of poisoned corpses out to sea.’
    • ‘From what I can ascertain after a quick search on the net, a parr is a juvenile form of salmon and/or trout.’
    • ‘To examine expression levels, muscle samples were taken from three body positions (anterior, middle, and posterior) of red and white muscle of five parr and five smolt rainbow trout.’
    • ‘Salmonids undergo a developmental transition from parr to smolt that involves a number of physiological and morphological changes.’
    • ‘Fishery inspectors have now pinpointed the source and they estimate the kill to be in the region of 3000 between salmon parr, and trout.’
    • ‘During this year's survey we counted over 600 salmon parr over two hours at Jervaulx on the Ure.’
    • ‘For example, what is the impact of mature parr on the sex ratio of wild Atlantic salmon populations, and what is the extent of their involvement in the breeding scheme compared to that of anadromous adult males?’
    • ‘After two years or sometimes more of stream life, steelhead parr begin their down river journey to the sea.’
    • ‘At least the salmon parr have been getting a break.’
    • ‘Shelter use by salmon parr is strongly density dependent, with a smaller percentage of the fish using available shelters when at high densities.’
    • ‘There is significant shift in the MHC composition of trout red muscle between parr and smolts.’
    • ‘The fish killed were salmon parr (one year old) and trout which would have been the future stock of the river.’
    • ‘Garant and his colleagues conclude in this month's scientific journal Ecology Letters, that the presence of farmed and hybrid male parr in salmon rivers ‘ultimately threatens the long-term genetic integrity of native populations’.’
    • ‘Okay, yeah, I've caught lots of parr, but not ‘proper’ salmon, and yet I've been fishing for 45 years.’
    • ‘The salmon parr were released at 12 sites including Shap, Sedbergh, Bentham and Ingleton.’
    • ‘Tailbeat frequency increases linearly with swimming speed in both parr and smolts.’


Early 18th century: of unknown origin.