Funding for composing and publishing this paper was provided through multiple grants and contracts to the Chironomidae Research Group (L. C. Ferrington, Jr., PI) in the Department of Entomology at the University of Minnesota. &#160;Thanks to Nathan Roberts for sharing fieldwork photographs used as figures in the video associated with this manuscript.

1. Preparation of Field Collection Supplies
<ol>
	<li>Determine the number of SFPE samples that should be collected based on the study design and acquire one sample jar (e.g., 60 ml) for each sample.</li>
	<li>Prepare two date and locality labels for each sample jar. Place one on the inside and affix the other to the outside of the jar. Ensure that each date and locality label includes the following information:&#160;&#160;country, state, county, city, water body, GPS coordinates, date, and name of person(s) c...

<ol>
	<li>Southerland, M. T., Stribling, J. B., Davis, W. S., Simon, T. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Biological Assessment and Criteria: Tools for Water Resource Planning and Decision Making. , 81-96 (1995).</li><li>Merritt, R. W., Cummins, K. W., Resh, V. H., Batzer, D. P., Merritt, R. W., Cummins, K. W., Berg, M. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> An Introduction to the Aquatic Insects of North America. , 15-37 (2008).</li><li>Ferrington, L. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Sediment and Stream Water Quality in a Changing Environment: Trends and Explanation. , 181-190 (1991).</li><li>Ferrington, L. C., Balian, E. V., L&#233;v&#234;que, C., Segers, H., Martens, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Freshwater Animal Diversity Assessment in Hydrobiology. , 447-455 (2008).</li><li>Ferrington, L. C., Berg, M. B., Coffman, W. P., Merritt, R. W., Cummins, K. W., Berg, M. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> An Introduction to the Aquatic Insects of North America. , 847-989 (2008).</li><li>Armitage, P. D., Cranston, P. S., Pinder, L. C. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Chironomidae: Biology and Ecology of Non-Biting Midges. 572, (1995).</li><li>Coffman, W. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Energy+Flow+in+a+Woodland+Stream+Ecosystem:+II.+The+Taxonomic+Composition+of+the+Chironomidae+as+Determined+by+the+Collection+of+Pupal+Exuviae.">Energy Flow in a Woodland Stream Ecosystem: II. The Taxonomic Composition of the Chironomidae as Determined by the Collection of Pupal Exuviae.</a> Archiv fur Hydrobiologie. 71, 281-322 (1973).</li><li>Anderson, A. M., Ferrington, L. C., Ekrem, T., Stur, E., Aagaard, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Proceedings of 18th International Symposium on Chironomidae on Fauna norvegica. 31, (2011).</li><li>Bouchard, R. W., Ferrington, L. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Effects+of+Subsampling+and+Sampling+Frequency+on+the+Use+of+Surface-Floating+Pupal+Exuviae+to+Measure+Chironomidae+(Diptera)+Communities+in+Wadeable+Temperate+Streams.">The Effects of Subsampling and Sampling Frequency on the Use of Surface-Floating Pupal Exuviae to Measure Chironomidae (Diptera) Communities in Wadeable Temperate Streams.</a> Environmental Monitoring and Assessment. 181, 205-223 (2011).</li><li>Wilson, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Monitoring+the+Effect+of+Sewage+Effluent+on+the+Oxford+Canal+Using+Chironomid+Pupal+Exuviae.">Monitoring the Effect of Sewage Effluent on the Oxford Canal Using Chironomid Pupal Exuviae.</a> Water and Environment Journal. 8, 171-182 (1994).</li><li>Wentsel, R., McIntosh, A., McCafferty, W. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Emergence+of+the+Midge+Chironomus+tentans+when+Exposed+to+Heavy+Metal+Contaminated+Sediment.">Emergence of the Midge Chironomus tentans when Exposed to Heavy Metal Contaminated Sediment.</a> Hydrobiologia. 57, 195-196 (1978).</li><li>Thienemann, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Das+Sammeln+von+Puppenh&#228;uten+der+Chironomiden.+Eine+Bitte+um+Mitarbeit.">Das Sammeln von Puppenh&#228;uten der Chironomiden. Eine Bitte um Mitarbeit.</a> Archiv fur Hydrobiologie. 6, 213-214 (1910).</li><li>Anderson, A. M., Kranzfelder, P., Egan, A. T., Ferrington, L. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Survey+of+Neotropical+Chironomidae+(Diptera)+on+San+Salvador+Island,+Bahamas.">Survey of Neotropical Chironomidae (Diptera) on San Salvador Island, Bahamas.</a> Florida Entomologist. 97, 304-308 (2014).</li><li>Coffman, W. P., de la Rosa, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Taxonomic+Composition+and+Temporal+Organization+of+Tropical+and+Temperate+Assemblages+of+Lotic+Chironomidae.">Taxonomic Composition and Temporal Organization of Tropical and Temperate Assemblages of Lotic Chironomidae.</a> Journal of the Kansas Entomological Society. 71, 388-406 (1998).</li><li>Brundin, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transantarctic+Relationships+and+their+Significance,+as+Evidenced+by+Chironomid+Midges.+With+a+Monograph+of+the+Subfamilies+Podonominae+and+Aphroteniinae+and+the+Austral+Heptagyiae.">Transantarctic Relationships and their Significance, as Evidenced by Chironomid Midges. With a Monograph of the Subfamilies Podonominae and Aphroteniinae and the Austral Heptagyiae.</a> Svenska Vetenskapsakademiens Handlingar. 11, 1-472 (1966).</li><li>Anderson, A. M., Ferrington, L. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Resistance+and+Resilience+of+Winter-Emerging+Chironomidae+(Diptera)+to+a+Flood+Event:+Implications+for+Minnesota+Trout+Streams.">Resistance and Resilience of Winter-Emerging Chironomidae (Diptera) to a Flood Event: Implications for Minnesota Trout Streams.</a> Hydrobiologia. 707, 59-71 (2012).</li><li>Ferrington, L. C., Anderson, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Contributions to the Systematics and Ecology of Aquatic Diptera-A Tribute to Ole A. Saether. , 99-105 (2007).</li><li>Bouchard, R. W., Ferrington, L. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Winter+Growth,+Development,+and+Emergence+of+Diamesa+mendotae+(Diptera:+Chironomidae)+in+Minnesota+Streams.">Winter Growth, Development, and Emergence of Diamesa mendotae (Diptera: Chironomidae) in Minnesota Streams.</a> Environmental Entomology. 38, 250-259 (2009).</li><li>Hardwick, R. A., Cooper, P. D., Cranston, P. S., Humphrey, C. L., Dostine, P. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spatial+and+Temporal+Distribution+Pattens+of+Drifting+Pupal+Exuviae+of+Chironomidae+(Diptera)+in+Streams+of+Tropical+Northern+Australia.+.">Spatial and Temporal Distribution Pattens of Drifting Pupal Exuviae of Chironomidae (Diptera) in Streams of Tropical Northern Australia. .</a> Freshwater Biology. 34, 569-578 (1995).</li><li>Wilson, R. S., Bright, P. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Use+of+Chironomid+Pupal+Exuviae+for+Characterizing+Streams.">The Use of Chironomid Pupal Exuviae for Characterizing Streams.</a> Freshwater Biology. 3, 283-302 (1973).</li><li>Raunio, J., Paavola, R., Muotka, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+Emergence+Phenology,+Taxa+Tolerances+and+Taxonomic+Resolution+on+the+Use+of+the+Chironomid+Pupal+Exuvial+Technique+in+River+Biomonitoring.">Effects of Emergence Phenology, Taxa Tolerances and Taxonomic Resolution on the Use of the Chironomid Pupal Exuvial Technique in River Biomonitoring.</a> Freshwater Biology. 52, 165-176 (2007).</li><li>Ruse, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lake+Acidification+Assessed+using+Chironomid+Pupal+Exuviae.">Lake Acidification Assessed using Chironomid Pupal Exuviae.</a> Fundamental and Applied Limnology. 178, 267-286 (2011).</li><li>Rufer, M. R., Ferrington, L. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sampling+Frequency+Required+for+Chironomid+Community+Resolution+in+Urban+Lakes+with+Contrasting+Trophic+States.">Sampling Frequency Required for Chironomid Community Resolution in Urban Lakes with Contrasting Trophic States.</a> Boletim do Museu Municipal do Funchal (Hist&#243;ria Natural) Supplement. 13, 77-84 (2008).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> CEN. 15196, 1-13 (2006).</li><li>Ferrington, L. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Collection+and+Identification+of+Surface+Floating+Pupal+Exuviae+of+Chironomidae+for+Use+in+Studies+of+Surface+Water+Quality.">Collection and Identification of Surface Floating Pupal Exuviae of Chironomidae for Use in Studies of Surface Water Quality.</a> Standard Operating Procedure No. FW 130A. , (1987).</li><li>Saither, O. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glossary+of+Chironomid+Morphology+Terminology+(Chironomidae+Diptera).">Glossary of Chironomid Morphology Terminology (Chironomidae Diptera).</a> Entomologica Scandinavica Supplement. 14, 51 (1980).</li><li>Pinder, L. C. V., Reiss, F., Wiederholm, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Chironomidae of the Holarctic region. Keys and Diagnoses Part 2. Pupa. 28, 299-456 (1986).</li><li>Wiederholm, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Chironomidae of the Holarctic region - Keys and Diagnoses, Part 2, Pupae. 28, (1989).</li><li>Merritt, R. W., Webb, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> An Introduction to the Aquatic Insects of North America. , (2008).</li><li>Wilson, R. S., Ruse, L. P., Sutcliffe, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> A Guide to the Identification of Genera of Chironomid Pupal Exuviae Occurring in Britain and Ireland (including Common Genera from Northern Europe) and Their Use in Monitoring Lotic and Lentic Fresh Waters. , (2005).</li><li>Egan, A. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Communities in Freshwater Coastal Rock Pools of Lake Superior, with a Focus on Chironomidae (Diptera). , (2014).</li><li>Raunio, J., Heino, J., Paasivirta, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Non-Biting+Midges+in+Biodiversity+Conservation+and+Environmental+Assessment:+Findings+from+Boreal+Freshwater+Ecosystems.">Non-Biting Midges in Biodiversity Conservation and Environmental Assessment: Findings from Boreal Freshwater Ecosystems.</a> Ecological Indicators. 11, 1057-1064 (2011).</li><li>Kavanaugh, R. G., Egan, A. T., Ferrington, L. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Factors+affecting+decomposition+rates+of+chironomid+(Diptera)+pupal+exuviae.">Factors affecting decomposition rates of chironomid (Diptera) pupal exuviae.</a> Chironomus: Newsletter on Chironomidae Research. 27, 16-24 (2014).</li><li>Anderson, A. M., Stur, E., Ekrem, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+and+Morphological+Methods+Reveal+Cryptic+Diversity+and+Three+New+Species+of+Nearctic+Micropsectra+(Diptera:+Chironomidae).">Molecular and Morphological Methods Reveal Cryptic Diversity and Three New Species of Nearctic Micropsectra (Diptera: Chironomidae).</a> Freshwater Science. 32, 892-921 (2013).</li><li>Ekrem, T., Willassen, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exploring+Tanytarsini+Relationships+(Diptera:+Chironomidae)+using+Mitochondrial+COII+Gene+Sequences.">Exploring Tanytarsini Relationships (Diptera: Chironomidae) using Mitochondrial COII Gene Sequences.</a> Insect Systematics &amp; Evolution. 35, 263-276 (2004).</li><li>Ekrem, T., Willassen, E., Stur, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Comprehensive+DNA+Sequence+Library+is+Essential+for+Identification+with+DNA+Barcodes.">A Comprehensive DNA Sequence Library is Essential for Identification with DNA Barcodes.</a> Molecular Phylogenetics and Evolution. 43, 530-542 (2007).</li></ol>

The authors declare that they have no competing financial interests.

The most critical steps for successful SFPE sample collection, picking, sorting, slide mounting, and identification are: (1) locating areas of high SFPE accumulation within the study area during field collection (Figure 2A); (2) slowly scanning the contents of the Petri dish for detection of all&#160;SFPE during sample picking; (3) developing the necessary manual dexterity to dissect the cephalothorax from the abdomen during slide mounting (Figure 4A); and (4) recognizing key morphologic...

Biological monitoring programs, which use living organisms to evaluate environmental health, are often used to assess water quality or monitor success of ecosystem restoration programs. Rapid bioassessment protocols (RBP) using benthic macroinvertebrate assemblages have been popular among state water resource agencies since 19891. Traditional methods of sampling benthic macroinvertebrates for RBPs, such as the dip-net, Surber sampler, and Hess sampler2, can be time-consuming, expensive, and may only measure assemblages from a particular microhabitat3. An efficient, alternative RBP for generating biological information about a particular water body involves collection of Chironomidae surface-floating pupal exuviae (SFPE)3.
The Chironomidae (Insecta: Diptera), commonly known as non-biting midges, are holometabolous flies that typically occur in aquatic environments before emerging as adults&#160;on the water&#8217;s surface. The chironomid family is species-rich, with approximately 5,000 species described worldwide; however, as many as 20,000 species are estimated to exist4. Chironomids are useful in documenting water and habitat quality in many aquatic ecosystems because of their high diversity and variable pollution tolerance levels5. Furthermore, they are often the most abundant and widespread benthic macroinvertebrates in aquatic systems, typically accounting for 50% or more of the species in the community5,6. Following emergence of the terrestrial adult, the pupal exuviae (cast pupal skin) remains floating on the water&#8217;s surface (Figure 1). Pupal exuviae accumulate along banks or behind obstructions through the action of wind or water current and can be easily and rapidly collected to give a comprehensive sample of chironomid species that have emerged during the previous 24-48 hr7.
The relative abundance and taxonomic composition of collected SFPE reflects water quality, considering that some species are very pollution tolerant, while others are quite sensitive5. The SFPE method has many advantages over traditional larval chironomid sampling techniques including: (1) minimal, if any, habitat disturbance occurs at a sampling area; (2) samples do not focus on collecting living organisms, but rather the non-living skin, so the trajectory of community dynamics is not affected; (3) identification to genus, and often species, is relatively easy given appropriate keys and descriptions3; (4) collecting, processing, and identifying samples is efficient and economical in comparison to traditional sampling methods3,8,9; (5) accumulated exuviae represent taxa that have originated from a wide range of microhabitats10; (6) the method is applicable in nearly all aquatic environments, including streams and rivers, estuaries, lakes, ponds, rock pools, and wetlands; and (7) SFPE maybe be a more sensitive indicator of ecosystem health since they represent individuals that have completed all immature stages and successfully emerged as&#160;adults11.
The SFPE method is not a new approach for gathering information about chironomid communities. Use of SFPE was first suggested by Thienemann12 in the early 1900s. A variety of studies have used SFPE for taxonomic surveys (e.g.,&#160;13-15), biodiversity and ecological studies (e.g. 7,16-19), and biological assessments (e.g.,20-22). Additionally, some studies have addressed different aspects of sample design, sample size, and number of sample events required for achieving various detection levels of species or genera (e.g.,8,9,23). These studies indicate that relatively high percentages of species or genera can be detected with moderate effort or expense associated with sample processing. For example, Anderson and Ferrington8 determined that based on a 100-count subsample, &#160;1/3rd less time was required&#160;to pick SFPE samples compared to dip-net samples. Another study determined that 3-4 SFPE samples could be sorted and identified for every dip-net sample and that SFPE samples were more efficient than dip-net samples at detecting species as species richness increased3. For example, at sites with species richness values of 15-16 species, the average dip-net efficiency was 45.7%, while SFPE samples were 97.8% efficient3.
Importantly, the SFPE method has been standardized in the European Union24 (known as chironomid pupal exuviae technique (CPET)) and North America25 for ecological assessment, but the method has not been described in detail. One application of the SFPE methodology was described by Ferrington, et al.3; however, the primary focus of that study was to evaluate the efficiency, efficacy, and economy of the SFPE method. The purpose of this work is to describe all steps of the SFPE method in detail, including sample collection, laboratory processing, slide mounting, and genus identification. The target audience includes graduate students, researchers, and professionals interested in expanding traditional water quality monitoring efforts into their studies.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>Ethanol</td>
			<td>Fisher Scientific</td>
			<td>S25309B&#160;</td>
			<td>70-95%</td>
		</tr>
		<tr>
			<td>Plastic wash bottles</td>
			<td>Fisher Scientific</td>
			<td>0340923B</td>
			<td></td>
		</tr>
		<tr>
			<td>Sample jar</td>
			<td>Fisher Scientific</td>
			<td>0333510B</td>
			<td>Glass or plastic, 60-mL recommended</td>
		</tr>
		<tr>
			<td>Testing sieve</td>
			<td>Advantech</td>
			<td>120SS12F</td>
			<td>125-micron mesh size</td>
		</tr>
		<tr>
			<td>Larval tray</td>
			<td>BioQuip</td>
			<td>5524</td>
			<td>White</td>
		</tr>
		<tr>
			<td>Stereo microscope</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Glass shell vials</td>
			<td>Fisher Scientific</td>
			<td>0333926B</td>
			<td>1-dram size</td>
		</tr>
		<tr>
			<td>Plastic dropper</td>
			<td>Thermo Scientific</td>
			<td>1371110</td>
			<td>30 to 35 drops/mL</td>
		</tr>
		<tr>
			<td>Fine forceps</td>
			<td>BioQuip</td>
			<td>4524</td>
			<td>#5</td>
		</tr>
		<tr>
			<td>Petri dish</td>
			<td>Carolina</td>
			<td>741158</td>
			<td>Glass or plastic</td>
		</tr>
		<tr>
			<td>Multi-well plate</td>
			<td>Thermo Scientific</td>
			<td align="right">144530</td>
			<td>Glass or plastic</td>
		</tr>
		<tr>
			<td>Glass microslides</td>
			<td>Thermo Scientific</td>
			<td>3010002</td>
			<td>3 x 1 in.</td>
		</tr>
		<tr>
			<td>Glass cover slips</td>
			<td>Thermo Scientific</td>
			<td>12-519-21G</td>
			<td>Circular or square</td>
		</tr>
		<tr>
			<td>Euparal mounting medium&#160;</td>
			<td>BioQuip</td>
			<td>6372B</td>
			<td></td>
		</tr>
		<tr>
			<td>Pigma pen</td>
			<td>BioQuip</td>
			<td>1154F</td>
			<td>Black</td>
		</tr>
		<tr>
			<td>Probe</td>
			<td>BioQuip</td>
			<td>4751</td>
			<td></td>
		</tr>
		<tr>
			<td>Kimwipes</td>
			<td>Kimberly-Clark Professional&#8482;</td>
			<td align="right">34120</td>
			<td></td>
		</tr>
	</tbody>
</table>

use of chironomidae (diptera) surface-floating pupal exuviae as a rapid bioassessment protocol for water bodies

Rapid bioassessment protocols using benthic macroinvertebrate assemblages have been successfully used to assess human impacts on water quality. Unfortunately, traditional benthic larval sampling methods, such as the dip-net, can be time-consuming and expensive. An alternative protocol involves collection of Chironomidae surface-floating pupal exuviae (SFPE). Chironomidae is a species-rich family of flies (Diptera) whose immature stages typically occur in aquatic habitats. Adult chironomids emerge from the water, leaving their pupal skins, or exuviae, floating on the water&#8217;s surface. Exuviae often accumulate along banks or behind obstructions by action of the wind or water current, where they can be collected to assess chironomid diversity and richness. Chironomids can be used as important biological indicators, since some species are more tolerant to pollution than others. Therefore, the relative abundance and species composition of collected SFPE reflect changes in water quality. Here, methods associated with field collection, laboratory processing, slide mounting, and identification of chironomid SFPE are described in detail. Advantages of the SFPE method include minimal disturbance at a sampling area, efficient and economical sample collection and laboratory processing, ease of identification, applicability in nearly all aquatic environments, and a potentially more sensitive measure of ecosystem stress. Limitations include the inability to determine larval microhabitat use and inability to identify pupal exuviae to species if they have not been associated with adult males.

Figure 1 illustrates the chironomid life cycle; immature stages (egg, larva, pupa) typically take place in, or closely associated with, an aquatic environment. Upon completion of the larval life stage, the larva constructs a tube-like shelter and attaches itself with silken secretions to the surrounding substrate and pupation occurs. Once the developing adult has matured, the pupa frees itself and swims to the surface of the water where the adult can emerge from the pupal exuviae. The exuviae fills with ...

Watch this Scientific Journal Video about Use of Chironomidae Diptera Surface-Floating Pupal Exuviae as a Rapid Bioassessment Protocol for Water Bodies at JoVE.com

Use of Chironomidae Diptera Surface-Floating Pupal Exuviae as a Rapid Bioassessment Protocol for Water Bodies

Rapid bioassessment protocols using benthic macroinvertebrates are often used to monitor and assess water quality. An efficient protocol involves collections of Chironomidae surface-floating pupal exuviae (SFPE). Here, techniques for field collection, laboratory processing, slide mounting, and identification of Chironomidae SFPE are described.

Use of Chironomidae (Diptera) Surface-Floating Pupal Exuviae as a Rapid Bioassessment Protocol for Water Bodies

Rapid bioassessment protocols using benthic macroinvertebrate assemblages have been successfully used to assess human impacts on water quality. ...

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11.5K Views.  University of Minnesota. Rapid bioassessment protocols using benthic macroinvertebrates are often used to monitor and assess water quality. An efficient protocol involves collections of Chironomidae surface-floating pupal exuviae (SFPE). Here, techniques for field collection, laboratory processing, slide mounting, and identification of Chironomidae SFPE are described.