1. Trophic relationships Feeding roles in streams

2. Aquatic insects categorized: Food type and how food is obtained Feeding guilds = functional groups

3. Base of trophic relationship Productivity from? Microbial loop: –Fungi, bacteria –Use dissolved organic carbon (DOC) –Passed to protozoans, etc.

4. Invertebrate consumers Food resources: –Periphyton –Macrophytes –Detritus –Animals

5. Feeding roles Shredders –Leaves, associated microbiota (CPOM) –Chewing –Trichoptera, Plecoptera, Diptera CPOM = > 1 mm

6. Feeding Roles Suspension feeder / filterer-collector –FPOM and microbiota –Sloughed periphyton –Use setae, nets, etc. –Net-spinning Trichoptera, Simuliidae, Ephemeroptera

7. Feeding Roles Deposit feeder / collector-gatherer –FPOM and microbiota –Browse, collect on surface, burrow –Ephemeroptera, Chironomidae, Ceratopogonidae FPOM = < 0.5 mm

8. Feeding Roles Grazer –Periphyton (mostly diatoms) by scraping –Macrophytes by piercing –Ephemeroptera, Trichoptera, Diptera, Lepidoptera, Coleoptera

9. Feeding Roles Predator –Animals –Biting, piercing –Odonata, Megaloptera, Plecoptera, Trichoptera, Diptera, Coleoptera

10. Terrestrial Stream CPOM DOM Leaching Microbes Shredders Feces FPOM

11. FPOM consumers Suspension and deposit feeders –Many adaptations for filtering –Philopotamidae caddisfly spins net

12. FPOM consumers Suspension feeder –Black fly larvae = Simulidae

13. FPOM consumers Deposit feeder = collector-gatherer –Some in sediments, some forage

14. Consumers of autotrophs Grazers, piercers –Graze periphyton –Scraping mouthpart adaptations –Water penny beetle larva Psephenus

15. Consumers of autotrophs Another grazer –Mayfly Stenonema –Brush algae, then collect it

16. Predators Most engulf prey entire or in pieces; others have piercing mouthparts

17. Problems with trophic classification Diet shifts with age and size Many very young invertebrates feed on fine detritus, then change