Biomonitoring the study of biological organisms and their responses to environmental conditions; can be fish, algae or insect communities

Benthic macroinvertebrates Benthic = Live on or in bottom substrate Macro = Large enough to be seen with unaided eye Invertebrate = Animal without a backbone

Why study macroinvertebrates? Affected by the physical, chemical and biological conditions of stream Can’t escape pollution - show the effects of short and long-term pollution events Can show the cumulative impacts of pollution May show the impacts of habitat loss

Why study macroinvertebrates? Critical part of the stream’s food web Relatively easy to sample and identify (easier than algae) Have greater diversity in stream than fish - sport fishing, stocking of fish and exotic species have altered fish community

IDENTIFICATION

Key identification features Overall body shape (NOT SIZE) Case made of sticks, leaves, stone Legs Presence and location of gills Presence and location of cerci (“tails”) Head capsule, unusual appendages Movement (crawl; swim side-to-side, up-down) These are the “key” features for getting to the order and family level; there are other common features such as wing pads, anal hooks, antennae, etc . Some family and most genus/species identification requires very specific microscope work to identify variations is small features, such as mandibles, toes, “bumps”, etc. Student Watershed Research Project (SWRP) Macroinvertebrates

Body shape Mayfly example of typical insect body: head, thorax, abdomen Student Watershed Research Project (SWRP) Macroinvertebrates

Case Case 1: Fall caddis (Family Limnephilidae, Genus Dicosmoecus) Case 2: American Grannom (Family Brachycentridae, Genus Brachycentrus) Case 3: Periwinkle, Cinnamon Sedge (Family Limnephilidae, 35+ genus in Oregon) Student Watershed Research Project (SWRP) Macroinvertebrates

Legs and prolegs Prolegs on midge Caddis removed from case Jointed legs are used primarily for movement. Prolegs are non-jointed appendages – aren’t easily identified as legs Prolegs on midge Caddis removed from case Student Watershed Research Project (SWRP) Macroinvertebrates

Gills Mayfly (Speckle-Winged Quill, Callibaetis) Presence, location and shape of gills is important for ID. Mayflies have abdominal gills, but the shape can vary. Mayfly (Speckle-Winged Quill, Callibaetis) Student Watershed Research Project (SWRP) Macroinvertebrates

Cerci (tails) Baetis has center tail that is ½ length of outer tails The number and length of tails/cerci can help with taxonomy. Keep in mind that fragile tails may break during collection, so number of tails should not be only ID feature used. Baetis has center tail that is ½ length of outer tails Student Watershed Research Project (SWRP) Macroinvertebrates

Head capsule Midges – head capsule Color can help, but isn’t a good means for sorting invertebrates Red midge on bottom is bloodworm, which is an example of where noting color can give information about organism. Bloodworms have hemoglobin – these organisms can obtain oxygen in low DO waters. Student Watershed Research Project (SWRP) Macroinvertebrates

Stoneflies (Plecoptera) Sensitive Nymphs: Two distinct "tails" called cerci, which are actually sensory feelers Usual movement = crawl; swim side-side Insect nymphs with three pair of jointed legs, each with paired claws. Two pair of wing pads (developing wings) present on thorax. No gills along abdomen Length up to 3 inches The name Plecoptera, derived from the Greek "pleco" meaning folded and "ptera" meaning wing, refers to the pleated hind wings which fold under the front wings when the insect is at rest. Student Watershed Research Project (SWRP) Macroinvertebrates

Stonefly nymph (Golden stone) Golden stone (Family Perlidae, Hesperoperla pacifica). This species is an example of sorting by key features and reaching a positive Genus/species identification. Student Watershed Research Project (SWRP) Macroinvertebrates

Stoneflies (Plecoptera) Sensitive Feeding types: Predator Shredder Omnivore Adults: resemble nymphs, but possess a long pair of wings folded down the length of the body. Eaten by a variety of fish species

Stonefly adult (Little Yellow Stone) Little Yellow Stone (Family Perlodidae, Genus Isoperla). Nymph is a predator which is sensitive to temperature and sediment pollution. Student Watershed Research Project (SWRP) Macroinvertebrates

Mayflies (Ephemeroptera) Sensitive Nymphs: Three tails, occasionally two Gills usually visible on abdomen Typical movement = crawl, swim (up-down) Small - Total length < 1 inch The name Ephemeroptera is derived from the Greek "ephemera" meaning short-lived, and "ptera" meaning wings.   This is a reference to the short lifespan of most adult mayflies. Student Watershed Research Project (SWRP) Macroinvertebrates

Mayfly nymph (Pale Evening Dun) Head is widest part of body Pale Evening Dun (Family Heptageniidae, Genus Heptagenia). Dorsal-ventrally flattened; 3 well developed tails; head is widest part of body Student Watershed Research Project (SWRP) Macroinvertebrates

Mayfly nymph (Small Yellow May) Nymph with only two tails Small Yellow May (Family Heptageniidae, Genus Epeorus). Dorsal-ventrally flattened; 2 tails; head is widest part of body Head is widest part of body Student Watershed Research Project (SWRP) Macroinvertebrates

Mayflies (Ephemeroptera) Sensitive Feeding Types: Collector-Gatherers Scrapers Adults: Resemble nymphs with two pair of long, lacy wings folded upright Adults usually have only two tails (cerci) Food for fish and predatory macroinvertebrates

Mayfly adult

Mayfly adult (Hexagenia) The genus Hexagenia (family Ephemeridae) is the exception to the rule that mayflies are usually small – some of these adults can be 2 inches long. Student Watershed Research Project (SWRP) Macroinvertebrates

Caddisflies (Tricoptera) Sensitive Larvae: Soft “worm-like”bodies Head contains a hard covering Larvae are known for their construction of hollow cases that they either carry with them or attach to rocks built from twigs or bark, small stones, or rolled leaves used for protection and pupation Anal hooks usually present Large - Length up to 2 inches The name Trichoptera, derived from the Greek words "trichos" meaning hair and "ptera" meaning wings, refers to the long, silky hairs that cover most of the body and wings. Student Watershed Research Project (SWRP) Macroinvertebrates

Caddisfly larvae w/ case October caddis Fall caddis (Family Limnephilidae, Genus Dicosmoecus) Student Watershed Research Project (SWRP) Macroinvertebrates

“Free-living” Caddisfly Spotted sedge Spotted sedge (Family Hydropsychidae, Genus Hydropsyche). All 3 thoracic segments have hardened exoskeleton; large anal hooks; Branched gills on abdomen Student Watershed Research Project (SWRP) Macroinvertebrates

Caddisflies (Tricoptera) Sensitive Feeding Types: Predators Grazers Collector-Gatherers Adults: “Moth-like”; usually nocturnal Wings fold into “tent” on back Eaten by fish and by some macroinvert predators Collector-Filterers Scrapers Shredders

Caddisfly adult (October caddis) Fall caddis (Family Limnephilidae, Genus Dicosmoecus) Student Watershed Research Project (SWRP) Macroinvertebrates

Water Pennies (Coleoptera) Sensitive Circular-shaped Attach firmly to rocks Sensitive – need high oxygen and fast flowing water The name Coleoptera, derived from the Greek words "koleos" meaning sheath and "ptera" meaning wings, refers to the modified front wings which serve as protective covers for the membranous hind wings. Student Watershed Research Project (SWRP) Macroinvertebrates

Megaloptera Sensitive Dobsonfly/ hellgrammites (Corydalidae) Large mandibles 2 short “tails” Predator Alderfly (Sialidae) Long, single “tail”                                                                                          Megaloptera have a large wing span (mega = large ptera = wing) - up to 16 cm. Corydalidae are sometimes called hellgrammites or toe biters. Student Watershed Research Project (SWRP) Macroinvertebrates

Odonata Wide range Damselfly Dragonfly 3 fan-shaped caudal gills Robust body Well-developed “jaws” The name Odonata, derived from the Greek "odonto-" meaning tooth, refers to the strong teeth found on the mandibles of most adults. Student Watershed Research Project (SWRP) Macroinvertebrates

Cranefly (Diptera) Wide Range Worm-like Head capsule, usually retracted into “accordion-like” body Shredders The name Diptera, derived from the Greek words "di" meaning two and "ptera" meaning wings, refers to the fact that true flies have only a single pair of wings. Student Watershed Research Project (SWRP) Macroinvertebrates

Midge Larvae (Diptera) Tolerant Pear-shaped body, with swollen base where they attach Filter feeders                                                                                               

Snails (Gastropoda) Tolerant Cylindrical shell May be right or left handed Gastro = stomach, poda = foot Student Watershed Research Project (SWRP) Macroinvertebrates

Others Tolerant Worms (Oligochaeta) Leeches (Hirundinea) Segmented bodies Leeches (Hirundinea) Suckers at both ends Oligo = little or few, chaeta = hairs Student Watershed Research Project (SWRP) Macroinvertebrates

Identification Are these the same organism? Soft or covered body? Head or head capsule? Legs or prolegs? Do we consider color? Student Watershed Research Project (SWRP) Macroinvertebrates

Green Rock Worm (Tricoptera) No case Predator Found in riffles Only first thoracic segment has hard shell Pair of anal hooks

Data Analysis Data collection is key Level of ID determines level of analysis Score (5) vs. interpretation (“POOR”) Use the same data analysis tool for comparing data Local-scale tool most accurate Requires time High quality “reference” sites Collecting and reporting the data is most important. The data can be interpreted many ways, but as long as all crucial data is reported (organisms, taxa, number in sample), a different data analysis tool can be applied to the same data in the future. Student Watershed Research Project (SWRP) Macroinvertebrates

Pollution Tolerance Index National-level tool ID to Order 3 groups Pollution Sensitive (3 pts) Wide Range (2 pts) Pollution Tolerant (1 pt) Data limited since # organisms not considered

Biometrics “Biometric” - a measure of some characteristic of the biological community Taxa Richness and Composition EPT Tolerance and Intolerance HBI Feeding Ecology % or abundance of functional feeding groups Population Attributes dominance “Biometrics” are usually only applied at the family or genus/species level. Student Watershed Research Project (SWRP) Macroinvertebrates

Family-level metrics Taxa Richness (# diff taxa identified) Mayfly Taxa Stonefly Taxa Caddisfly Taxa % Diptera HBI Examples from Guide to Pacific Northwest Aquatic Invertebrates by Rick Hafele and Steve Hinton (available through Oregon Trout) Student Watershed Research Project (SWRP) Macroinvertebrates

Multi-metric indices Include several (usually 5-10) metrics Combined, they measure various aspects of stream health Examples: Index of Biological Integrity (IBI) State of Oregon Multi-metric Index Student Watershed Research Project (SWRP) Macroinvertebrates