Warmwater Streams Chapter 19

Warmwater Streams Coolwater, warmwater Water temperatures high enough to prevent salmonids from remaining throughout the year, reproducing- >24°C Coolwater, warmwater

Warmwater Streams Many different game fish Multi-species assemblages

Warmwater Streams Classification of warmwater streams Based on physical, biological factors

Longitudinal Zonation River Continuum Concept

Longitudinal Zonation River Continuum Concept

Longitudinal Zonation River Continuum Concept

Longitudinal Zonation River Continuum Concept Headwater - tolerant, good recolonizers, small Midreach - greater diversity (habitat, species) Biological regulation becomes more important Mainstem - greater diversity, body size

Major Historical Problems Sedimentation Water table alteration

Management Differences from coldwater streams: More affected by humans - habitat, water quality Multi-species recreational fishery Lack of ecological data on fish, other biota

Species Management Approach What’s good for top carnivores should be good for entire stream

Community Management Approach Stresses balance of taxonomic or ecological groups What’s good for community should be good for sport fish

Habitat Many considerations: Depth Structure Riparian vegetation Sedimentation Hydraulic stability

Habitat Depth: Cover Low-water or winter refuge Habitat for forage fish

Habitat Structure: Woody snags Channel diversity Cover Invertebrate habitat

Habitat Riparian vegetation: Buffer strips

Habitat Sedimentation: Watershed vs. streambed, banks (50%)

Habitat Hydraulic stability: Discharge patterns Channel stability

Habitat Major goals: 1) maintain, restore hydraulic stability 2) improve diversity of depth, structure

Stocking Warmwater Streams Not a general policy No perceived need Unnecessary

Stocking Warmwater Streams May help in some situations Deal with inconsistent reproductive success Expand fishing opportunities in western warmwater streams (too warm for salmonids)

Regulations Usually no special regulations Usually identical to lake regulations Only 4 states or provinces with extensive warmwater stream regulations Others with special regs for only few streams

Regulations General failure to acknowledge warmwater streams as deserving of habitat-specific management for recreational fisheries