2015 Aquatic Plant Surveys

Transcription

1 Lake Puckaway 2015 Aquatic Plant Survey Results June 13, 2016 Shallow Lakes are Special Clear State Turbid State Brenton Butterfield Tim Hoyman Paul Garrison Aquatic Plants are Incredibly Important Shallow Lakes are Special Aquatic Plants Stabilize bottom sediments Provide zooplankton habitat Uptake of nutrients from water (coontail, waterweed) Create more diverse fishery Factors which cause loss of aquatic vegetation cause transition to turbid state Excessive nutrient loading Water level stabilization Benthivorous fish (e.g. common carp) Once in a turbid state, very difficult to revert back to clear state 2015 Aquatic Plant Surveys Assess both non native & native species Four surveys completed in 2015 Early Season AIS Survey Whole Lake Point Intercept Survey Emergent/Floating Leaf Community Mapping Survey Late Summer EWM Peak Biomass Survey June 13,

2 Whole Lake Point Intercept Survey: July 20 21, 2015 Lake Puckaway 155 meter resolution 872 total points Aquatic Plant Survey Results Summary 45 Species Located 17 emergent or floatingleaf 23 submergent 1 submergent/emergent 4 free floating 39 Native Species 6 Non Native Pale yellow iris Purple loosestrife Hybrid water milfoil Brittle Naiad Curly leaf pondweed Curly leaf hybrid Growth Form Emergent FL Submergent Scientific Name Common Name Coefficient of Conservatism (C) 2015 (Onterra) Bolboschoenus fluviatilis River bulrush 5 I Eleocharis erythropoda Bald spikerush 3 I Iris pseudacorus Pale-yellow iris Exotic I Lythrum salicaria Purple loosestrife Exotic I Phragmites australis subsp. americanus Common reed 5 I Sagittaria latifolia Common arrowhead 3 I Sagittaria rigida Stiff arrowhead 8 X Schoenoplectus acutus Hardstem bulrush 5 X Schoenoplectus pungens Three-square rush 5 I Schoenoplectus tabernaemontani Softstem bulrush 4 I Sparganium eurycarpum Common bur-reed 5 I Typha spp. Cattail spp. 1 I Zizania spp. Wild rice sp. 8 I Nelumbo lutea American lotus 8 X Nuphar variegata Spatterdock 6 X Nymphaea odorata White water lily 6 X Persicaria amphibia Water smartweed 5 I Ceratophyllum demersum Coontail 3 X Chara spp. Muskgrasses 7 X Elodea canadensis Common waterweed 3 X Heteranthera dubia Water stargrass 6 X Myriophyllum sibiricum Northern water milfoil 7 X Myriophyllum sibiricum X spicatum a Hybrid water milfoil Exotic X Najas flexilis Slender naiad 6 X Najas guadalupensis Southern naiad 7 X Najas minor Brittle naiad Exotic X Potamogeton berchtoldii Slender pondweed 7 X Potamogeton crispus Curly-leaf pondweed Exotic I Potamogeton friesii Fries' pondweed 8 I Potamogeton X rectifolius b Clasping-leaf X Long-leaf pondweed N/A I Potamogeton natans Floating-leaf pondweed 5 X Potamogeton nodosus Long-leaf pondweed 5 I Potamogeton richardsonii Clasping-leaf pondweed 5 I Potamogeton strictifolius Stiff pondweed 8 X Potamogeton X undulatus b Curly-leaf X White-stem pondweed Exotic I Potamogeton zosteriformis Flat-stem pondweed 6 I Stuckenia pectinata Sago pondweed 3 X Utricularia vulgaris Common bladderwort 7 X Vallisneria americana Wild celery 6 X Zannichellia palustris Horned pondweed 7 X S/E Eleocharis acicularis Needle spikerush 5 X FF Lemna minor Lesser duckweed 5 X Lemna trisulca Forked duckweed 6 X Spirodela polyrhiza Greater duckweed 5 X Wolffia spp. Watermeal spp. N/A X 2015 Point Intercept Survey: Substrate 2015 Point Intercept Survey: Vegetation Distribution Max Depth of Plants: 5.0 feet Number of Littoral Sampling Locations: 679 Veg. Littoral Freq. of Occurrence: 19.3% TRF = 3 2% Soft Sediments Rock Sand E Non-navigable/Temporary Obstacle Soft Sediments 81% Sand 19% Rock 0% E No Vegetation Total Rake Fullness = 1 E Deeper Than Max Depth of Plants (5.0 feet) E Non-Navigable TRF = 2 5% TRF = 1 13% No Vegetation 80% Total Rake Fullness = 2 Total Rake Fullness = 3 June 13,

3 Aquatic Plant Species Littoral Frequency of Occurrence 2005, 2014, & 2015 Survey Comparison 100 Overall Occurrence of Vegetation Littoral Frequency of Occurence (%) Littoral Frequency of Occurrence (%) % Reduction (Statistically Valid) 40% Reduction (Statistically Valid) 21.6 Not Statistically Different & 2015 Survey Comparison Wisconsin Ecoregions (Maxim Technologies) 2015 (Onterra) Littoral Frequency of Occurrence (%) * Occurrence statistically diff erent from 2005 (Chi-square α =.005) 10 0 * * * * * * * * * June 13,

4 2005, 2014, & 2015 FQI Comparison 2005, 2014, & 2015 Simpson s Diversity Simpson's Diversity Index Simpson s Diversity 2005: : : Median Outlier 0.00 SWTP Maximum Upper Quartile Lower Quartile Minimum State Lake Puckaway 2005 Lake Puckaway 2014 Lake Puckaway Emergent & Floating leaf Communities Curly Leaf Pondweed Small Plant Community Large Plant Community Emergent Emergent Floating-Leaf Floating-Leaf Mixed Emergent Mixed Emergent & Floating-Leaf & Floating-Leaf Mixed Emergent & Floating-leaf 96 Acres 14% Floating-leaf 478 Acres 70% Emergent 105 Acres 16% Total Acres: 679 (~13% of lake area) Highly Highly Surface Matting Single or Few Plants Clump of Plants Small Plant Colony 1.3 Acres 21% Highly 4.6 Acres 77% Total Acres: Acres 2% June 13,

5 Curly Leaf Pondweed Hybrid Hybrid Water Milfoil Highly Highly Single or Few Plants Clump of Plants Small Plant Colony 11.6 Acres 15% 22.6 Acres 29% Highly 36.3 Acres 47% Highly 2.6 Acres 3% Surface Matting 4.6 Acres 6% Surface Matting Total Acres: 77.7 Brittle Naiad Aquatic Plant Community Conclusions Native Plant Community Species richness, diversity, and average conservatism are high, but Overall occurrence of submersed vegetation is very low High quality native emergent/floating leaf plant communities present (limited in area) Reduced light availability, carp, and unnatural water level regime inhibit growth Non Native Plants Few occurrences of purple loosestrife & pale yellow iris Occurrence of CLP (& CLP hybrid) & brittle naiad low HWM most prevalent non native plant (~78 acres) Highly Highly Surface Matting Single or Few Plants Clump of Plants Small Plant Colony Located on Rake During PI Survey June 13,

6 Thank You Many of the graphics used in this presentation were supplied by: Wisconsin Lakes Partnership June 13,