Salmonid Fish Habitat Applications of habitat data to

Salmonid Fish Habitat

Applications of habitat data to fishery management Distribution and abundance of habitat for different life stages • Barriers to migration; Waterfalls / dams • Adult habitat; Deep pools / cover • Spawning habitat; Glides / smaller substrates • Fry habitat; Shallow / smaller substrates • Parr habitat; Deeper / larger substrates Assessing habitat quality & condition • Cover for fish; in-stream and bank structure • Climate control; shading • Pressures; impacts of Land water use

In-stream cover Shelter & territories; physical cover from floods & predators • • • Size of substrates – Roughness layer Interstitial spaces – subsurface layer Flow type Vegetation Large woody debris

Flow cover • Riffle / Run – Broken water • Glide / Pool – depth or canopy

Bank-side cover • • • Undercut Draped vegetation Tree roots Rock Marginal vegetation Other

Typical habitat requirements Life Stage Salmon Brown Trout Spawning Eggs Alevins 3+ m channel width Glide or riffle flow (35 -80 cm/sˉ¹) Water depth 17 -76 cm Substrate Golf–tennis ball (20100 mm) Low fines (< 1 mm) 2. 3 – 8 % Depth of substrate >15 – 25 cm < 3 m channel width Glide or riffle flow (15 -75 cm/sˉ¹) Pea-tennis ball substrate size Low fines (< 1 mm) 8 – 12 % Depth of substrate >14 cm Fry (< 1 yr) < 20 cm depth Golf – tennis ball substrate size Shallow / broken water / Fast flow Golf ball – tennis ball substrate Shallow /medium flow / marginal cover Parr (=> 1 yr) 20 – 40 cm depth Tennis – football substrate Variety of substrate Deeper / broken water / fast flow Deeper / slower water Undercut banks / tree roots Smolt Habitat connectivity Adult Deep pools > 80 cm depth Deep water > 0. 4 m depth Slow sustained flow Bank / bed / canopy cover

Habitat / River Sequence Juvenile Adult Spawn

Habitat / River Sequence Adult Juvenile Spawn

Typical salmon habitat – low gradient Mixed juvenile habitat (0 – 1++) Adult pool habitat Spawning habitat Fry habitat

Typical salmon habitat – moderate gradient Adult pool habitat Spawning habitat Mixed parr habitat (1 – 2+) Fry habitat

Typical trout habitat - tributaries Spawn Habitat Fry habitat Parr / adult habitat

Typical trout habitat – larger streams Spawn Habitat Adult pool habitat fry habitat Parr habitat

SFCC walkover Field surveys– Main components General observations • Channel dimensions; Area of habitat • Channel type; gradient / character • In-stream cover; Flow & substrate types / LWD • Bank cover; bank type / riparian vegetation / shade Point location observations • O. S Grid refs; Survey start / end points • Spawning; Area / type / condition • Adult pools; Area / depth / cover • Obstacles; type / height / fish passage • Modifications; revetment / embankment / pollution