Monitoring Wetland Health in the Credit River Watershed

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1 Monitoring Wetland Health in the Credit River Watershed Preliminary Results and Trends Aviva Patel

2 Terrestrial Monitoring Goals Identify status and trends in wetland health parameters at the watershed scale, link to watershed health Identify spatial patterns in wetland health parameters Provide meaningful data on which watershed management decisions can be based

3 Why Monitor Wetlands? Wetlands provide numerous functions: Flow moderation Water purification Erosion control Carbon sequestration Wetland Monitoring allows: Detection of habitat loss or degradation Adaptive environmental management

4 Credit River Watershed

5 Credit Valley Watershed Physiographic Zones Lower: Heavily urbanized Middle: Niagara Escarpment & Oak Ridges Moraine Upper: Urban, agriculture and natural Monitoring Sites 18 Vegetation Sites 26 Amphibian Sites

6 Wetland Indicators Wetland Health Landscape Vegetation 4 years Regeneration Ground cover Wildlife 6 years Marsh birds Amphibians (frogs & toads) Water

7 Wetland Cover 6% of watershed area <3% in Lower Watershed Fair Good in Middle and Upper Watersheds ~48% wetland loss since % swamp, 18% marsh

8 Wetland size Majority of wetlands <1ha but these contribute only 25% of total wetland area Frequency % of area >100 Wetland size class (ha)

9 Vegetation - Methods EMAN & CVC Methodology 50 m transect 12 subplots 2 x 2 m Regeneration 1 x 1 m Vegetation All taxa identified to species & percent cover recorded

10 Vegetation - Indicators Richness Diversity Locally and Regionally rare species Floristic Quality Assessment Mean Coefficient of Conservatism (mcc) CC 8-10 Average Wetness Average Weediness Weediness Score -3

11 Vegetation - Results 465 herbaceous and woody plants identified to species level (37% of watershed total) 82% native 6% 10% 0% 8% Tree 0% Shrub 2% 17% Forb Fern 4% Vine Rush Grass Sedge Other 53%

12 Vegetation species richness & diversity Temporal Trends Ground Vegetation Increasing plant species richness and diversity Richness Increasing knowledge of sites Changes in monitoring team Diversity

13 Vegetation native species Temporal patterns Proportion of native species decreasing over time Proportion of Native Species Year

14 Vegetation native species Spatial patterns Proportion of native species Lower < Middle and/or Upper 1.00 Proportion of Native Species Year Lower Middle Upper

15 Vegetation weedy species Temporal patterns Number of weedy species (Weediness score - 3) is increasing 3 Mean -3 Per Site Year

16 Vegetation weedy species Spatial patterns -3 weedy species different among zones Lower > Middle & Upper 5 Number of Species Lower Middle Upper Year

17 Amphibians - Methods Marsh Monitoring Program protocols Calls recorded to estimate amphibian numbers and species C1 calls not overlapping C2 calls overlapping C3 full chorus

18 Amphibians - Indicators Frogs and toads: Richness Abundance Site Occupancy

19 Amphibians trend analysis Nine species detected, only mink frog not detected No observable trend in amphibian species richness, abundance or site occupancy over the monitoring period Species richness per site Amphibians number of species per site Year

20 Amphibians spatial analysis Species richness varied between physiographic regions Lower < Middle and/or Upper Amphibian Species Richness Species richness per site Year Lower Middle Upper

21 Amphibians spatial analysis Spring Peeper absent from Lower zone Photo credit: Toronto Zoo No full chorus of any frog or toad species detected in Lower zone

22 Summary Relatively stable plant and amphibian richness and diversity Relatively stable trends in plant wetness index and coefficient of conservatism Data suggest urbanization is affecting native biodiversity Lower Watershed has fewer amphibian species and lower proportion of native plants than Middle and Upper Watershed Increasing numbers of -3 level weedy species in watershed

23 Future Work Increase number of sites Panel design to minimize impact on sites Addition of hydrology and water quality parameters

24 Thank you