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Published byTiffany Allyson Chase Modified over 9 years ago
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Chris Nagai Nick Foster Christen Dschankilic Streams of Science
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Pickering Watershed
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How We Didn’t Do It Study Chemicals Precise indication of quality Brief snapshot Expensive Study fish Data represents greater time period Difficult to catch Collection can damage live samples
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How Did We Do It? Study Benthic Macroinvertebrates Positives Represents good time period Good indication of quality Easy to collect Negatives Collection can damage samples Difficult to ID
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The Protocol Systematic set up of transects Systematic set up of transects Notation of riparian data, etc Collection of sample with D-nets Randomized selection of insects to be counted Identify samples
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Credible Carefully followed protocol Protocol recognised by Citizen’s Environment Watch (CEW) as well as Conservation Authority
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Indices % Aquatic Worm %Midge%Sowbug # of Taxa %Snail %Dominant Taxa %EPT%Diptera%Insects Hilsenhoff Biotic Index (HBI) Based on these indices our streams can be rated unimpaired or possibly impaired
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Aquatic Worm % Indicates an area with low oxygen levels Indicates an area with low oxygen levels This makes it harder for other macroinvertebrates to survive A high percentage often indicates poor water quality A high percentage often indicates poor water quality
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Midge % Midges are found in almost every type of habitat Midges are found in almost every type of habitat A high percentage of midges indicates unhealthy stream conditions A high percentage of midges indicates unhealthy stream conditions However, their absence is often unexpected and can indicate potential damage of a stream. However, their absence is often unexpected and can indicate potential damage of a stream.
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# of Taxa A high number of taxa (groups) indicates good water quality This is because in order for a great variety of species to exist at the same site, there must be a diverse range in habitats.
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EPT This index consists of three groups of macroinvertebrates; mayflies, stoneflies, and caddisflies All three require high quality stream environments Thus, a high percentage of EPT indicates good water and habitat quality.
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HBI This index shows the nutrient levels of the stream It incorporates the tolerance value of each group to give a snap shot of the nutrient conditions A low HBI value implies low nutrient conditions A high HBI implies excessive nutrient conditions.
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Gandi Possibly impaired (5 unimpaired, 2 possibly impaired, 3 impaired) Midge levels are declining and EPT is rising River appears improving Not enough bugs found, therefore technically not valid data
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Urfe This year was found to be potentially impaired. 3 unimpaired 3 possibly impaired, 4 impaired Doing well in 2007 and 2008
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Little Rouge Unimpaired (7 unimpaired, 3 possibly impaired) River is improving EPT is starting to decline, Midges are on the rise River is good, but needs help to stay that way
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Box Grove Box Grove is possibly impaired (4 unimpaired, 1 possibly impaired, 5 impaired) Consistently large amounts of Midges with low EPT and poor HBI Small river next to subdivision under construction Rainbow trout nest found.
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Conclusion Our rivers appear to be improving from past years Action should be taken to keep it that way. Human activity like construction (Box Grove) can be detrimental
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