Macroinvertebrates may be small and

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1 Monitoring your Wetland a primer to site-level monitoring activities for volunteer coordinators Macroinvertebrates Macroinvertebrates may be small and spineless, but when it comes to the cycling of wetland nutrients there s nary a niche where you won t find them. Some, HIGH HIGH like snails, graze peacefully on aquatic plants, while others, like dragonfly nymphs, voraciously prey on other invertebrates. Sowbugs, caddisfly larvae, clams LOW LOW and other janitorial macroinvertebrates recycle decomposing and particulate matter. Finally, all macroinvertebrates provide food for other wetland animals. Most macroinvertebrates are too small to noticeably stir the water s surface, but are large enough to see with the naked eye. They include EXPERTISE RESOURCES small worms, mollusks, leeches, crustaceans, insects and insect larvae. Besides playing a star role in many important Snail wetland functions, macroinvertebrates are sometimes employed as a tool for characterizing aquatic habitats and learning about aquatic habitat water quality. Macroinvertebrates are sensitive to physical, chemical and biological environmental stressors. And because of their limited mobility, they cannot easily avoid pollution, low oxygen levels or other unfavorable conditions. Bob Korth Macroinvertebrate monitoring can help characterize wetlands, but as a water quality indicator, wetland macroinvertebrate monitoring has not yet matured. In other aquatic habitats, and particularly streams, macroinvertebrate monitoring has a long history as a tool for assessing water quality. Volunteers who monitor macroinvertebrates in streams look for the presence, absence or dominance of sensitive or tolerant species and then use a biotic index of health to interpret what they indicate about the quality of the stream. About Macroinvertebrate Surveys Crayfish Unfortunately, macroinvertebrate monitoring in wetlands is much more challenging than in streams. The macroinvertebrate community found in a wetland will differ considerably from the communities in other wetland types. And, because there is a great deal of variation among wetland types, it is difficult to standardize protocol for collecting repre sen tative macroinvertebrate samples or identifying a healthy or unhealthy macro invertebrate community. Consequently, it is also difficult to determine when variations in sampled macroinvertebrate This publication is part of a Monitoring Your Wetland series available online in pdf format at: wetlandmonitoring.uwex.edu

2 Jeffrey J. Strobel photos Wetlands alongside a lake Bog wetland Wetland with ponds About Macroinvertebrate Surveys continued from front page communities are due to wetland degradation or natural wetland characteristics. Differences in wetland characteristics that have nothing to do with degradation can influence the presence or absence of various species of macroinvertebrates. In contrast to shallow, land-locked wetlands, for example, wetlands connected to lakes or rivers typically have fish, which tend to reduce macroinverte brate abundance and species diversity. Additionally, naturally high levels of acidity in bogs can also reduce macroinvertebrate diver sity, but don t necessarily indicate poor wetland quality. Macroinvertebrate monitoring is one of the more difficult and costly monitoring efforts a wetland volunteer monitoring group can engage in. Wetland monitoring groups often become frustrated trying to achieve satisfactory results if they are determined to develop a complete inventory of wetland macroinvertebrate species or monitor macroinvertebrates as an indicator of wetland quality. When trying to monitor macroinvertebrates as indicators, sampling, picking and especially specimen identification can be difficult. All of this having been said, macroinvertebrate monitoring may be a great activity to Macroinvertebrate monitoring may be a great activity to engage your volunteers in if your primary goals are to raise awareness and characterize the wetland. engage your volunteers in if your primary goals are to raise awareness and characterize the wetland. Macroinvertebrate monitoring is a good way to teach volunteers about wetland ecology. And identifying some of the types of macroinvertebrates living in your wetland contributes to what you know about it. This publication outlines some basic macroinverte brate survey methods that can be applied to a broad range of wetland types. These are methods designed to help maximize volunteers ability to produce an inventory of species that will help characterize a wetland. We will not explain what sampling results indicate about wetland health, since methods for doing so are nascent even for professional biologists. But for those of you interested in experimenting with preliminary methods for mon itoring macroinvertebrates as wetland health indicators, we will briefly describe and provide references to projects testing such methods in Midwestern wetland areas (see Informational Resources on the back page). 2

3 Supplies and Equipment Costs for the equipment, supplies and possibly laboratory services needed to support macroinvertebrate monitoring can range from moderate to high depending on the rigor of the identification standards used. Monitoring will, at minimum, require equipment for collecting samples. Depending on how you structure your volunteer group s monitoring activities, they may also need equipment and supplies for separating specimens from organic matter, identification and preserving specimens. For Collecting Samples Volunteers need at least three basic pieces of equipment to gather macroinvertebrate samples. First, they need D-frame macroinvertebrate sampling dip nets and basins or pails for holding samples. Recommended mesh sizes for the sampling nets ranges from 600-1,200 microns. Finer mesh nets will capture more macroinvertebrates, but will also clog easily and can collect an unnecessarily large, debris-laden sample. Finally, because volunteers need to leave dry land to collect samples, they will also need hip boots or waders and possibly a canoe. For Picking Specimens When volunteers sample macroinvertebrates from a wetland they will almost definitely gather a great deal of organic matter and need to pick macroinvertebrate specimens from a mat of duckweed, plant fragments and muck. White invertebrate counting trays made out of fiberglass or plastic will help volunteers sort through the mess. Trays used to hold collect ed samples while volunteers pick specimens out of organic matter should be light-weight, flat-bottomed and shouldn t twist or easily spill. Macroinvertebrate picking trays can come in a variety of sizes, but a typical tray might measure 25 cm wide, by 30 cm long and 5 cm deep. Some volunteer groups use dish pans, which are affordable and easy to find. To assist in separating organic matter from macroinvertebrate specimens you may also want to provide each volunteer with a framed screen. The screen frame can be made out of wood and the screen can be made out of chicken wire, hardware cloth or other wire mesh with holes big enough for large macroinvertebrates to fall through, but small enough to hold back a large quantity of vegetative matter. The screen frame should just fit within the perimeter of a tray and suspend the screen below the lip of the tray and above the tray bottom. You will also need tools for grabbing and removing specimens from organic matter, such as forceps and eyedroppers. Volunteers may prefer different tools for picking and you may want to experiment with a number of tools, such as plastic spoons, basting brushes or turkey basters. For Identification and Preserving After picking, you will need additional supplies and possibly laboratory services to complete the identification process. For rudimentary identification that can be conducted in the field, volunteers will need a few basic supplies including macroinvertebrate taxonomic keys, ice cube trays for sorting picked macroinvertebrates into families, hand-held magnifying glasses and data recording sheets. For more rigorous identification, volunteers will need access to a laboratory supplied with microscopes. If they are not identifying in the field, they will also need supplies for preserving specimens including vials or bottles to hold macroinvertebrates and a preservative, such as alcohol or glycerin. To obtain the most rigorous identification of sample specimens, volunteer groups will need professional laboratory services. Unfortunately, laboratory services can cost hundreds of dollars and often exceed the resources available to many volunteer monitoring groups. 3

4 Volunteers empty a D-frame sampling dip net into containers. As little as two to three hours of field training may be sufficient to train volunteers to collect samples. However, picking, and particularly identifying macroinvertebrates, can be very difficult and requires a high level of skill that cannot be taught over a short period of time. wetland macroinvertebrate monitoring A team will require a highly skilled team leader and moderate-to-high skill levels among other volunteers, depending on the design of the monitoring effort. Three tasks must be completed to determine the types and species of macroinvertebrates present in a wetland. Samples must be collected, macro invertebrates must be picked from the organic matter mixed in the sample and the macroinvertebrates must be identified. Samples must be collected using consistent methods, but volunteers can learn these methods Survey Participants relatively easily when taught by an experienced instructor. As little as two to three hours of field training may be sufficient to train volunteers to collect samples. However, picking, and particularly identifying macroinvertebrates, can be very difficult and requires a high level of skill that cannot be taught over a short period of time. If you ask volunteers to pick and identify specimens, you will need a highly experienced team leader to ensure volunteers are properly picking and to double check identifications. Generally, volunteers are said to struggle with identifying down to the family level. 4

5 Surveying When, Where & How to Sample To get the most representative macroinvertebrate sample possible, volunteers need to sample at the right time and in the right locations. Volunteers don t need to wake up before dawn or limit monitoring to days with low wind speeds, but they do need to take samples at the right time of year. The best time to sample macroinvertebrates is roughly from early June through July or mid-august. Samples collected earlier could contain large numbers of underdeveloped organ isms, which will be difficult to identify. Sampling is typically completed before August, since by late summer the macroinvertebrate community is more likely to include macroinvertebrates that have migrated in from connected water bodies and will be less representative of the wetland. Also, in late summer many wetlands can become dry. Volunteers can determine where to sample by examining wetland vegetative composition and water depths. Volunteers should sample macroinvertebrates from both emergent herbaceous plant communities (the underwater portion) and submerged and floating aquatic communities when both are present. They should also take samples that represent a range of water Depending on how dense the vegetation is, volunteers should sample in water depths ranging from no deeper than hip level down to ankle level. D-frame dip net, macroinvertebrate key, containers and tools. depths. Depending on how dense the vegetation is, volunteers should sample in water depths ranging from no deeper than hip level down to ankle level. In deep water volunteers may find sowbugs, midges and worms, but macroinvertebrate diversity will be low compared with shallow water areas surrounded by emergent vegetation. When taking a sample, volunteers should sweep the net through the entire water column with a vigorous jabbing motion, starting near the sediment surface. With each jab of the net, the volunteer reaches outward and then rapidly pulls toward their body with the net, dislodging macroin vertebrates from emergent and floating vegetation. When a volunteer reaches the water s surface with their sample, they should deposit it in a pail. To ensure the pail contains a robust collection of macro invertebrates, the volunteer should dipnet one to two more additional samples in the same general area and combine them in the pail with the first. These two to three samples will be treated as one sample when picking and identifying. 5

6 Unless you send unpicked samples to a lab for identification, volunteers will need to learn how to pick macroinvertebrates from the organic matter scooped up in their dip nets. Even if your volunteers will be sending sampled specimens to a lab for professional identification, your group will likely want to pick the samples first since laboratory fees for unpicked samples are very high. Volunteers should process samples right away while the macroinvertebrates are still moving and easy to see. To pick, volunteers should spread their sample over screens placed inside white picking trays. The macroinvertebrates will squirm down toward the bottom of the tray to escape the light and fall through the screen into the tray. Volunteers should let the sample sit for about five to ten minutes while the macroinvertebrates move down. Physical features examined to identify macroinvertebrates include overall body shape, number and location of legs, presence and location of gills and tails, the shape of the head capsule and unusual appendages. Macroinvertebrate casings and mode of locomotion can also be used to identify macroinvertebrates. Some crawl, swim side to side or swim updown. And among Surveying Picking & Preserving Identification Sorted macroinvertebrates and identification notes. After allowing the sample to settle for five to ten minutes, the screen and organic matter caught by it can be removed. Before removing the screen, volunteers should inspect it for invertebrates that did not move down into the tray. After removing the tray, volunteers can begin picking. Volunteers should continue to pick either until they have picked 150 specimens from their sample or have been picking for 30 minutes. To avoid picking bias, volunteers should resist the urge to ignore macroinvertebrates that are difficult to pick because they are fast or very small. Volunteers should pick big, small, slow and fast macroinvertebrates. Volunteers should use tweezers or an eye dropper to grab specimens, then drop them into a jar or bottle of water for temporary storage until they can be sorted and/or preserved. those that have casings, some have a case of sticks and others a case of stone. Even with all of these possible distinguishing features, macroinvertebrate identification is incredibly difficult. Unless your volunteers are retired entomologists, they will probably only be able to identify most macroinvertebrates down to the order or family taxonomic levels. Non-expert entomologists will 6

7 MACROINVERTEBRATES Tubifex worm: Jason Neuswanger, troutnut.com; scud and black fly: Missouri Dept. of Conservation; mayfly: Dr. Stanley Szczytko, UW-Stevens Point Tubifex worm Scud or sideswimmer Black fly larva Mayfly typically not be able to identify macroinvertebrates down to the species or even the genus level. If it is important to you to have a large proportion of sampled macroinvertebrates identified down to the genus or species level and you have substantial resources to support the monitoring project, you might consider sending samples to a professional lab for identification. Laboratories in Stevens Point and at UW-Superior offer identification services. A monitoring project can expect to pay approximately $150 in laboratory fees to have a single pre-sorted sample of macroinvertebrate specimens identified down to the lowest practical taxonomic level, usually genus or species. If you plan to have volunteers identify macroinvertebrates in the field, they ll need ice cube trays for separating macroinvertebrates into families and macroinvertebrate identification informational resources. Two online identification resources are listed among the Informational Resources on the back page a guide to macroinvertebrates of the Upper Midwest and a flow chart for identifying common macroin vertebrates found in Wisconsin wetlands. The Key to Life in the Wetlands flow chart 7

8 Monitoring your Wetland a primer to site-level monitoring activities for volunteer coordinators Macroinvertebrates INFORMATIONAL RESOURCES Minnesota Pollution Control Agency Macroinvertebrate Community Sampling Protocol for Depressional Wetland Monitoring Sites This document outlines protocol developed for expert-led volunteer monitoring of depressional wetlands in Minnesota. The methods are designed to use macroinvertebrate monitoring as a means of assessing water quality and require identification of macroinvertebrates down to the genus or species level using microscopes. (see website link on wetland monitoring site) Field Testing the Wisconsin Depressional Wetland Macroinvertebrate and Plant Indices of Biological Integrity for Application by Trained Volunteers This report documents the effectiveness of Wisconsin Department of Natural Resources developed macroinvertebrate and plant biotic index for assessment of isolated depressional wetlands in Wisconsin, when used by DNR biologists not trained in aquatic entomology. (see website link on wetland monitoring site) The Monitoring Your Wetland series includes 9 sections: Introduction to Wetland Monitoring Birds Small Mammals Dragonflies & Damselflies (Odonata) Frogs and Toads (Anurans) Butterflies (Lepidoptera) Invasive Plants Water Quality Macroinvertebrates Available online in pdf format at: wetlandmonitoring.uwex.edu Great Lakes Coastal Wetlands Consortium Great Lakes Coastal Wetlands Monitoring Plan The fourth chapter of this plan outlines protocol for monitoring macroinvertebrates in Great Lakes coastal wetlands. Requires laboratory identification of macroinvertebrates down to species and genus level. Water Action Volunteers Biotic Index This Web page and linked documents are designed to help volunteers monitor macroinvertebrates in streams as part of the Water Action Volunteers program. These guidelines cannot be used to monitor macroinvertebrates in wetlands, but can be used when wetland volunteers monitoring a wetland in which there is a stream would like to monitor the stream. University of Minnesota, Guide to the Aquatic Invertebrates of the Upper Midwest This guide provides an identification key for common aquatic invertebrates found in the Upper Midwest, based on mature larvae or adults. Wisconsin Department of Natural Resources and University of Wisconsin Extension Key to Life in the Wetlands This is a flow chart for identifying common macroinvertebrates found in many Wisconsin wetlands. This chart is handy for identification of macroinvertebrates in the field. University of Wisconsin-Superior and University of Wisconsin-Stevens Point Laboratory Identification Services For macroinvertebrate identification contact either UW-Superior Aquatic Entomology Assistant Professor Kurt Schmude, kschmude@uwsuper.edu (715) or UW-Stevens Point Aquatic Entomology Laboratory Supervisor & Research Specialist Jeff Dimick, jdimick@uwsp.edu (715) March 2011 Project coordination by the Rock River Coalition and Suzanne Wade, UW-Extension Basin Education Initiative. Researched and written by Patrice Kohl With editorial contributions from Kurt Schmude University of Wisconsin-Superior assistant professor, aquatic entomology; and Dick Lillie, biologist. Editorial assistance by Marie Martinelle and graphic design by Jeffrey J. Strobel, UW-Extension Environmental Resources Center. Photography by Kris Stepenuck/Citizen Monitoring except where otherwise noted. Project funded through a DNR Citizen-Based Monitoring Partnership Program Grant with support from University of Wisconsin-Extension. University of Wisconsin, U.S. Department of Agriculture and Wisconsin counties cooperating. An EEO/AA employer, University of Wisconsin Extension provides equal opportunities in employment and programming, including Title IX and American with Disabilities (ADA) requirements.