Biology & Ecology of SE MN Karst Region Streams Macroinvertebrate Ecology & Bioassessments

1. Biology & Ecology of SE MN Karst Region StreamsMacroinvertebrate Ecology & Bioassessments

2. Natural History of Stream Invertebrates: Making Sense of Biotic Indices

3. Segment 2 Outline • Roles and types of aquatic macroinvertebrates • Habitats, feeding, life histories, and tolerance • Biological integrity and its application in southern MN

4. Freshwater Ecology light substrate temperature current Physical pH photosynthesis DO Biological Chemical macrophytes [nutrients] macroinvertebrates fish alkalinity

5. The Importance of Macroinvertebrates • Macroinvertebrates are an essential component of freshwater ecosystems • They serve as food for • other organisms (fish, amphibians and waterfowl) • Are essential to the breakdown and cycling of organic matter and nutrients • Macroinvertebrate diversity is vital to a properly functioning ecosystem

6. Why Study Macroinvertebrates? • Macroinvertebrates are used to assess the health of freshwater environments • Some macroinvertebrates are sensitive to stress produced by pollution, habitat modification, or severe natural events • Sampling and identifying macroinvertebrates can reveal whether a body of water is healthy or unhealthy and may reveal the cause of the problem

7. Why are macroinvertebrates biological indicators of stream health? • Spend up to one year (or more) in the stream • Have little mobility • Generally abundant • Primary food source for many fish • Good indicators of local conditions • Diversity = healthy stream • Easy to sample Adult Caddisfly

9. Stream Benthic Macroinvertebrates: Standard Habitat Samples from Iowa Streams

10. Common Macroinvertebrates Mayflies (Ephemeroptera) Isonychiidae Ephemerellidae Heptageniidae Baetidae (Adult)

11. Common Macroinvertebrates Stoneflies (Plecoptera) Pteronarcydiae Perlidae Perlodidae (Adult)

12. Common Macroinvertebrates Caddisflies (Trichoptera) Brachycentridae Phryganeidae Hydropsychidae Philopotamidae Case (Adult)

13. Common Macroinvertebrates Damselflies and Dragonflies (Odonata) True Bugs (Hemiptera) Dobsonflies, Alderflies and Fishflies (Megaloptera) Beetles (Coleoptera)

14. Common Macroinvertebrates True Flies (Diptera) Midge (Chironomidae) Blackfly (Simuliidae) Midge adult Cranefly (Tipulidae)

15. Common Macroinvertebrates Crayfish and Amphipods(Crustacea) Snails/Mussels (Mollusca) Worms and Leeches(Oligochaeta) Planarians (Platyhelminthes)

16. Macroinvertebrate Biology Habitat Movement Feeding Life History Stress Tolerance Use in Biomonitoring

17. Habitat The place where an organism lives Running waters – lotic – seeps, springs, brooks, branches, creeks, streams, rivers Standing waters – lentic – bogs, marshes, swamps, ponds, lakes erosional (riffles, wave action) or depositional areas (point bars, pools) Mineral bedrock, boulders, cobbles, pebble, gravel, sand, silt, clay Organic live plants, detritus

18. Movement Locomotion, habits, or mode of existence Clingers – maintain a relatively fixed position on firm substrates in current Climbers – dwell on live aquatic plants or plant debris Crawlers – have elongate bodies with thin legs, slowly move using legs Sprawlers – live on the bottom consisting of fine sediments Burrowers – dig down and reside in the soft, fine sediment Swimmers – adapted for moving through water Skaters – adapted to remain on the surface of water

19. Feeding Macroinvertebrates are described by how they eat, rather than what they eat Functional Feeding Groups – categories of macroinvertebrates based on body structures and behavioral mechanisms that they use to acquire their food

20. Shredders Chew on intact or large pieces of plant material • Material is usually >1 mm, referred to as Coarse Particulate Organic Matter (CPOM) Shredder-herbivores feed on living aquatic plants that grow submerged in the water (northern casemaker caddisflies) Shredder-detritivores feed on detritus, or dead plant material in a state of decay (giant stoneflies)

21. Collectors Acquire and ingest very small particles (<1 mm) of detritus, often referred to as fine particulate organic matter (FPOM) Collector-gatherers – eatfine detritus that has fallen out of suspension that is lying on the bottom or mixed with bottom sediments Collector-filterers- use special straining mechanisms to feed on fine detritus that is suspended in the water

22. Piercers mouthparts, or sometimes their entire head, protrude as modifications to puncture food and bring out the fluids contained inside Piercer-herbivores – penetrate the tissues of vascular or aquatic plants or individual cells of filamentous algae and suck the liquid contents (crawling water beetles, microcaddisflies) Piercer-predators– subdue and kill other animals by removing their body fluids

23. Scrapers/Grazers • Adapted to remove and consume the thin layer of algae and bacteria that grows tightly attached to solid substrates in shallow waters • Jaws of scrapers have sharp, angular edges (function like using a putty knife or paint scraper) • (flathead mayflies, water pennies, snails)

24. Engulfer-Predators Feed upon living animals, either by swallowing the entire body of small prey or by tearing large prey into pieces that are small enough to consume (common stoneflies and hellgrammites)

26. Autochthonous vs. Allochthonous Inputs Autochthonous– biomass produced within the system (in stream) - algae, periphyton, macrophytes Allochthonous– biomass produced outside the system (riparian and upland) - tree and shrub leaves and needles Light is a primary determinant of whether the food base for a given community is live green plants growing within the aquatic environment or decaying plant material that originated in the terrestrial environment

27. Functional Feeding Groups: The River Continuum(Vannote et al., 1980) • HEADWATERS: • Shredders abundant • Coarse POM CPOM STREAM ORDER FPOM • MID-REACHES: • Grazers abundant • Higher 1° production FPOM • LARGE RIVERS: • Collectors abundant • Fine-Ultra fine POM Relative Channel Width

28. Life History Reproduction, growth, and development of an organism Hermaphroditic organisms – contain both male and female reproductive organs (flatworms, aquatic earthworms, leeches, snails) Oviparous – females lay their eggs outside of their body Ovoviviparous – females retain their eggs and allow them to hatch within their body and release free-living offspring Growth is relatively simple in flatworms, aquatic earthworms and leeches because they are not restricted by any type of external protective structures Exoskeleton of arthropods does not grow once it has been produced, so growth of the organism is restricted. As a result, arthropods must shed their skin (molt) in order to increase in size (3-45 times). Mollusks are enclosed in non-living protective shells produced by the organism; shells are made of protein and calcium carbonate; made larger by adding material, like a tree growth ring

29. Insect Life Cycles • Metamorphosis - • biological process involving a conspicuous and relatively abrupt change in the insect's body structure through cell growth and differentiation. • Complete metamorphosis is egg > larva (nymph) > pupa > adult Incomplete metamorphosis

30. Insect Life Cycles • Many (but not all) of the aquatic macroinvertebrates are in the larval or nymphal stage while in a stream, and will eventually leave the water when they are adults that can fly. • Adult insects often have very short life spans, maybe only 24 hours or a few days. These insects may not live very long once removed from their stream habitat.

31. Voltinism • Many invertebrates can pass through only a single generation each year (or less), while others are capable of 2 or more generations • Univoltine– one brood or generation per year (most mayflies, caddisflies) • Bivoltine- two broods or generations per year (baetid mayflies) • Multivoltine- more than two broods or generations per year (some mayflies like Tricorythodes) • Semivoltine- generation time is more than one year (many stoneflies, dragonflies)

32. Stress Tolerance Natural volcanoes, forest fires, floods, landslides Anthropogenic pollution, removal of water by irrigation, dams, deforestation, removal of riparian vegetation Freshwater invertebrates vary in their ability to cope with environmental stress Biomonitoring takes advantage of this situation by identifying whether an aquatic environment is inhabited predominantly by stress tolerant or stress intolerant organisms

33. Classification of Macroinvertebrates used in Biomonitoring Kingdom: Animalia Phylum: Arthropoda (Arthropods) Annelida (Segmented Worms) Mollusca (Mollusks)

34. Group 1 Taxa Pollution Sensitive Organisms Found In Good Quality Water Stoneflies Mayflies Water Pennies Dobsonflies Riffle Beetles Mussels

35. Stonefly Water Penny Beetle Mayfly Dobsonfly Alderfly Mussel Snipe Fly Riffle Beetle Macroinvertebrates as Indicators Pollution Sensitive (“Clean Water”) Benthos

36. Group 2 Taxa Can Exist Under a Wide Range of Water Quality Conditions Generally of Moderate Quality Water Caddisflies Damselflies Dragonflies Blackflies Craneflies Water Boatman Backswimmers Crayfish Amphipods

37. Macroinvertebrates as Indicators Somewhat Pollution Tolerant Benthos BlackflyCaddisfly Isopod Cranefly Damselfly Dragonfly Crayfish Amphipod

38. Group 3 Taxa Can Exist Under a Wide Range of Water Quality Conditions, Generally are Highly Tolerant of Poor Quality Water Midgeflies/Chironomids Worms Leeches Pouch Snails

39. Macroinvertebrates as Indicators Pollution Tolerant (“Polluted Water”) Benthos Pouch Snail Midgefly Worm Leech

40. The Tolerance Index0 - 10 0 10 most pollution sensitive e.g. Stoneflies most pollution tolerant e.g. Midges & Leeches contain hemoglobin, tolerate lower DO, prefer soft substrate, less sensitive to toxins require high DO, clear water, rocky cobble substrate

41. HBI_MN Tolerance Values from Joel Chirhart Hexatoma 8.07 Ophiogomphus 0 Hesperophylax 2.67 Perlodidae 2.68 Stenelmis 8.30 Lepidostoma 0.12 Baetidae 7.18 Caenis 8.79 Ephemerella 0.26 Hyalella 7.30 Orconectes 9.41 Glossosoma 1.14 Hydropsychidae 7.55 Physa 10 Acroneuria 2.40

42. EPT Tolerance Values Family (Species range) Ephemerellidae 1 (0-2) Taeniopterygidae 2 (2-3) Rhyacophilidae 0 (0-1) Leptophlebiidae 2 (1-6) Brachycentridae 1 (0-2) Capniidae 1 (1-3) Isonychiidae 2 (2-2) Limnephilidae Baetiscidae 3 Leuctridae 0 (0-0) 4 (0-4) Heptageniidae 4 (0-7) Hydropsychidae Perlidae 1 (0-4) 4 (0-6) Caenidae 7 (3-7)

43. Other taxa tolerance values, Family (species) Elmidae 4 (2-6) Corydalidae 0 (4) Psephenidae 4 (4-5) Gomphidae 1 (1-5) Tipulidae 3 (2-7) Aeshnidae 3 (2-6) Chironomidae Tanypodinae (4-10) Podonominae (1-8) Calopterygidae 5 (5-6) Simulidae 6 (1-7) From: Benthic Macroinvertebrates in Freshwaters- Taxa Tolerance Values, Metric and Protocols (Mandaville 2002)

44. Biological Integrity “…the capability of supporting and maintaining a balanced, integrated, adaptive community of organisms having a composition, diversity and functional organization comparable to that of natural habitats of the region” (Karr and Dudley 1981)

45. J.R. Karr • First developed biotic index for fish • Became multi-metric index • IBIs are now used world-wide for many different taxa • Must be regionally calibrated with reference sites

46. The Index of Biotic Integrity (IBI) is useful because… • It is an ensemble of biological information • It objectively defines benchmark conditions • It can assess change due to human causes • It uses standardized methods • It scores sites numerically, describes in narrative form • It defines multiple condition classes • It has a strong theoretical basis • It does not require fine resolution of taxa

47. Benthic Macroinvertebrates Hydropsyche sp. (Caddisfly larva) Heptageniidae sp. (Mayfly larva) Perlodidae sp. (Stonefly larva) • Great candidates for biological monitoring…

48. Macroinvertebrates as Indicators • Limited migration patterns – good indicators of localized conditions and site-specific impacts • Integrate effects of human impacts** • Easy to sample and identify • Broad range of habitat requirements and sensitivities to pollution

49. Integrate effects of human impacts

50. EPA Recommendations • Build a comprehensive bioassessment data base • Test and validate metrics, or indices, to ensure they are reliable indicators of human disturbance and are able to discern between changes due to natural variability and human activity • Adopt numeric biocriteria for specific waterbody types sequentially into water quality standards as EPA publishes technical guidance for those waters