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Delineation of the Monoecious Hydrilla Discovery in Cayuga Lake at Aurora, NY Presence and Location of Hydrilla at Wells College Bay ---PAGE BREAK--- Cover Map and Monitoring Numbers The map on the cover shows the results of our rake-toss survey describing the presence and location of Hydrilla verticillata at Wells College Bay in Aurora, NY during 2016. Each icon an evaluation of hydrilla presence at a predetermined location identified by the interception of the X and Y lines of the Universal Transverse Mercator (UTM) coordinate system at North American Datum 1983 (NAD 83), true north. This method assumes that the data values recorded from the collections of the two-thrown rake tosses at the point of the line intercepts is representative of the aquatic plant species present within a 25m X 25m area grid. This finer search pattern of 25m X 25m rather than a typical 100m X 100m or 50m X 50m search grid allows us to better search the lake area with the greatest probability of new hydrilla finds. The map boxes in RED type are locations where hydrilla was found during our survey. The BLACK type boxes were locations where we did not find hydrilla. 2 ---PAGE BREAK--- Contents List of List of Introduction and Summary Results Report to the Finger Lakes PRISM and New York State Department of Environmental Conservation. Prepared by Racine-Johnson Aquatic Ecologists 1185 Ellis Hollow Road Ithaca, NY 14850 Robert L. Johnson [EMAIL REDACTED] January 2017 3 ---PAGE BREAK--- Tables Table 1. Abundance categories or rake-toss ratings used to describe a collected sample assumes mean dry weight ranges for spreadsheet processing of field data. Our estimate of abundance allows the use of a visual depiction of the mass of all individual species combined as well as the mass of individual Figures Figure 1. Example of a small section of our UTM grid used to predetermine locations to sample aquatic plant presence and abundance. Locations sampled are at points defined by the line intercepts of the NAD 1983 X coordinate East and NAD 1983 Y coordinate Figure 2. Sampling team on Cayuga (left) while processing a macrophyte sample from dual- headed rakes by separating to individual species for an estimate of each species’ percentage of the whole mass Figure 3. Best-fit line to describe the relationship between onsite estimates of abundance made with the rake-toss method of collection contrasted with a measured estimate of biomass (three individual in-lake biomass quadrat experiments determined the regression equation) Figure 4. The red blocks indicate the locations of where positive hits of Hydrilla were found along a 25m X 25m UTM Figure 5. Estimated area that should be considered as a potential treatment zone. The teal area expands beyond the red blocks containing Hydrilla for a conservative approximation of the concerned Figure 6. Adjusted depths for an accurate estimate of each depth per rake-toss abundance location. Depths were adjusted to those of the USGS surface elevation in Ithaca, NY in July of 2016 to present an accurate Figures 7 – 23. Map locations of groups and individual aquatic plant species and the relative abundance assigned to each. Two rake-tosses at each location determined the values…………………….13 4 ---PAGE BREAK--- Introduction and Summary We submit this 2016 report to the Finger Lakes PRISM and the New York State Department of Environmental Conservation. This document summarizes the 2016 aquatic plant evaluations from our plant monitoring survey in the Wells College Bay in Aurora, NY. This delineation, is a first step toward eradication of Hydrilla verticillata from this area. Hydrilla fragments were found Sept. 13, 2016 a few hundred meters south of the Wells College dock during sampling by the Cayuga Lake Floating Classroom with Wells College Campus Greens. The identification and expert verification of monoecious H. verticillata (hydrilla) in the Wells College Bay at Aurora, NY prompted a rapid response to stop the spread from the Wells College Bay of this non-native invasive to neighboring water and waterways. A local effort began immediately to identify the location and extent of the hydrilla growth. Several volunteers sampled the area recording the GPS (global positioning system) locations of hydrilla found by visually by divers and tethered double headed garden rakes by others. We depict the initial 2016 hydrilla findings by our survey by tossing a two-headed rake twice at each location (Figure The presence of hydrilla was wide spread over the bay area and likely covers an area greater than 27 acres. The density and spread pattern of hydrilla observed at individual locations within the bay suggests the hydrilla has been in the bay for several years. To cover this ~ 27-acre area with hydrilla from an assumed single point introduction we suggest that the introduction took place at least 5 years previous. We base this on the growth rate and spread possible in one year that we observed with the finding of hydrilla beds in the SE corner of Cayuga Lake at Ithaca in 2014 from hydrilla likely introduced in the summer of 2013 (Johnson 2013, 2014, 2015 and 2016). The prevailing winds from the NW likely play a part in the spread and rate. Additionally, the anecdotal information that the Cayuga Inlet introduction was 2007 - 2008 (Johnson 2013, 2014, 2015 and 2016). Locations with hydrilla identified by this project in 2016 are available on the website iMapInvasives owned by NatureServe, http://www.imapinvasives.org/new-yorklogin. Funding for the NY iMapInvasives Project is provided by the New York State Environmental Protection Fund through the New York State Department of Environmental Conservation. This report lists aquatic plant data collected by surveys in 2016 using the line intercept method (Madsen 1999) by Racine-Johnson Aquatic Ecologists of Ithaca, NY. We determined the presence and location of plant species by this line-intercept method and additionally added an estimate of each species’ abundance (estimated biomass) from each rake-toss. We depict this 2016 information in tables, and abundance pictorials as maps to provide current information about the aquatic plant community. Methods used for this delineation are the same as Racine-Johnson Aquatic Ecologists has used in the southern end of Cayuga Lake since 2011 through 2016 with the Ithaca project to eradicate hydrilla from the Cayuga Inlet, Fall Creek and the southeast corner of Cayuga Lake (Johnson 2013, 2014, 2015, and 2016). This location has some special challenges to a successful control and eradication of hydrilla. These include but are not limited to a portable water intake, possible high traffic area, water depths to hydrilla of 17 to 18+ feet, potential fast flushing rate and probable frequent high wave action. Wave height is influenced by wind speed, wind duration (how long the wind blows) and fetch all likely at this location. 5 ---PAGE BREAK--- Methods The survey team applied a systematic search grid using the line intercept method (Madsen 1999) to hunt for the presence of monoecious hydrilla. Additionally, we identified all individual aquatic plant species present and estimated the relative abundance of each species to document the plant community structure. We sampled and recorded aquatic plant species presence and abundance at pre-selected locations determined by overlaying a UTM grid in Wells College Bay at Aurora, NY in 2016 (Figure Racine-Johnson Aquatic Ecologists from Ithaca NY collected the 2016 rake-toss data presented in this report. We used a basic line intercept sampling method to preselect locations to sample by using a global positioning system (GPS) to guide us to sampling points defined by a geographic information system (GIS). Monitoring crews in boats tossed a tethered dual-headed rake to collect data from two rake tosses at each sample point of a 25m X 25m UTM (NAD 1983 datum and True North) transect grid. Hand-held and/or boat-mounted GPS equipment guided our movement to these locations. Members of the sampling crew tossed the double-headed rake at each selected location and then pulled the rake along the bottom about 10 meters. The individual throwing the rake lifted any plant mass into the boat or to shore. An estimate of overall plant abundance and individual species percentages of the total plant mass from each randomly tossed rake enhanced the basic line intercept method described by Madsen 1999. Figure 1. Example of a small section of our UTM grid used to predetermine locations to sample aquatic plant presence and abundance. Locations sampled are at points defined by the line intercepts of the NAD 1983 X coordinate East and NAD 1983 Y coordinate North. The monitoring team then separated each plant mass collected by rake into individual species, analyzed the separations by recording the species identification (Borman et al. 1999, Crow and Hellquist 1999) and assigned a percentage estimate of mass to each species (Figure We use a classification of dense, medium, sparse, trace or zero to classify the overall plant biomass of each individual rake toss. A rating of “dense” is more than an armful 6 ---PAGE BREAK--- and difficult to get into the boat, while an arm-full or when all rake tines are full receives a “medium” rating. A “sparse” is when two hands are full or about 50% of the tines on the rake are full, a “trace” is less than a small handful or when plants are on a couple of rake tines, and a “zero” is a bare rake. Figure 2. Sampling team on Cayuga (left) and processing a dense macrophyte samples from dual-headed rakes by separating to individual species for an estimate of each species’ percentage of the whole mass (right). To obtain an all-species combined (native and non-native) abundance value at a specific location for the pictorial abundance maps in Wells College Bay we simply average the two on-water estimated rake abundance categories for the two rake tosses at each location to produce a mean value. For example, at the sample location if rake-toss one is an armful or all the rake tines very full, that plant mass is recorded as a medium or abundance rating of 3 (Table If the second rake-toss at that location amounts to a small handful or less, or if using a similar method estimating amount on the rake as about two tines full on a rake that is recorded as a (trace) or an abundance value rating of 1 (Table If we have a rake-toss of a value rating 3 (medium) and the second rake- toss as a rating of 1 (trace), we calculate the mean as 2 or a (sparse) for that location. If we recorded one rake-toss as a (medium) and the second as a bare rake the mean would be a value of 1.5, also a (sparse), (Table Table 1. Abundance categories or rake-toss ratings used to describe a collected sample assumes mean dry weight ranges for spreadsheet processing of field data. Our estimate of abundance allows the use of a visual depiction of the mass of all individual species combined as well as the mass of individual species. We base our abundance analysis for each rake toss on our broad categories of rake-toss abundance reported in the field. Our abundance ratings originate from assumptions based on the biomass relationship to rake-toss shown in (Figure 3) and determined by field experiments. Abundance Categories Rake-toss Abundance Rating Dry Weight (g/m2) Ranges associated with Total Plants Abundance ~ Range Midpoint (g/m2) for calculation Dry Weight (g/m2) Ranges associated with Single Species Abundance = no plant(s) 0 ~ 0 0 same = trace plant(s) 1 ~ 0.0001 – 0.999 0.5 same = sparse plant(s) 2 ~ 1 – 24.999 13 same = medium plant(s) 3 ~ 25 – 99.99 62.5 same = dense plant(s) 4 ~ 100 – 400+ 250 same 7 ---PAGE BREAK--- After observational data collected from pre-determined locations in Wells College Bay arrives at our office, members of our team enter the information into MS Excel spreadsheets, check the spreadsheet for data entry errors, perform analysis and list in a report. Data tables 1 and 2 in the appendix are the actual field collected observations that are transformed into pictorial depictions that appear as abundance values in figures 7 – 23. We show in Figure 4 specific depictions of hydrilla locations. Specific coordinate locations of hydrilla finds in 2016 are in the appendix of this report as a table, Coordinates 1. Additionally, we recorded this data on the iMapInvasives website owned by NatureServe. http://www.imapinvasives.org/new-yorklogin Figure 3. Best-fit line to describe the relationship between onsite estimates of abundance made with the rake-toss method of collection contrasted with a measured estimate of biomass (three individual in-lake biomass quadrat experiments determined the regression equation). To analyze the abundance data of individual species we used the values in Table 1. Specifically, the standard assumed abundance rating or category as it relates to dry biomass (g/m2). Figure 3 describes the foundation for Table 1 concluded from experiments conducted in Chautauqua Lake, NY during 2006 and 2007 (Johnson 2008). Along with additional data collected in 2011, we contrasted the “rake-toss” estimates at specific locations to the absolute dry biomass data collected from the same locations at the same time. We used 28 lake locations, collected five 0.25m2 quadrat samples from each location for a total of 140 biomass samples and determined dry mass by drying the quadrat samples to 105oC. We calculated a mean biomass dry weight (g/m2) for each of the 28 locations. From this quadrat biomass sampling and the accompanying rake- toss estimate of abundance, we determined the best-fit regression line shown in Figure 3. In practice using the relationships in Table 1 and the 2016 rake-toss data sets we calculated mean species abundances for each location sampled by using the field percent estimate of each biologist’s rake toss. With the use of GIS, we placed the resulting abundance values on individual species maps for each sampled location to create a visual record of the relative species abundance for all locations. In the Results section following, the Wells College Bay abundance maps show the rake-toss results for the Wells College Bay area. 4 3 2 1 0 1000 100 10 1 0.1 0.01 0.001 Rake-toss Abundance Rating Biomass g/m2 DW S 0.345182 R-Sq 89.5% R-Sq(adj) 88.6% Regression 95% CI 95% PI Biomass vs Rake-toss Relationship 8 ---PAGE BREAK--- Results This report summarizes and displays the results of the 2016 aquatic plant species monitoring for the Wells College Bay in the figures that follow. Figure 4. The red blocks indicate the locations of where positive hits of Hydrilla were found along a 25m X 25m UTM grid. 9 ---PAGE BREAK--- Figure 5. Minimum estimated area that should be considered as a potential Hydrilla treatment zone for the Wells College Bay based on Hydrilla presence. The teal area expands beyond the red blocks containing Hydrilla for a conservative approximation of the concerned area. 10 ---PAGE BREAK--- Figure 6. Adjusted depths for an accurate estimate of each depth per rake-toss abundance location. Depths were adjusted to those of the USGS surface elevation in Ithaca, NY in July of 2016 to present an accurate depth. 11 ---PAGE BREAK--- Figure 7. All species combined as abundance by two rake tosses. All species combined Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 12 ---PAGE BREAK--- Figure 8. Native species combined as abundance by two rake tosses. Native species combined Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 13 ---PAGE BREAK--- Figure 9. Non-native species combined as abundance by two rake tosses. Non-native species combined Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 14 ---PAGE BREAK--- Figure 10. demersum (coontail) as abundance by two rake tosses. demersum (coontail) Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 15 ---PAGE BREAK--- Figure 11. Chara vulgaris (muskgrass) as abundance by two rake tosses. Chara vulgaris (muskgrass) Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 16 ---PAGE BREAK--- Figure 12. Elodea sp. (elodea) as abundance by two rake tosses Elodea sp. (elodea) Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 17 ---PAGE BREAK--- Figure 13. Heteranthera dubia (water stargrass) as abundance by two rake tosses. Heteranthera dubia (water stargrass) Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 18 ---PAGE BREAK--- Figure 14. Hydrilla verticillata (hydrilla) as abundance by two rake tosses. Hydrilla verticillata (hydrilla) Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 19 ---PAGE BREAK--- Figure 15. spicatum (Eurasian watermilfoil) as abundance by two rake tosses. spicatum (Eurasian watermilfoil) Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 20 ---PAGE BREAK--- Figure 16. Najas flexilis (slender water as abundance by two rake tosses. Najas flexilis (slender water Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 21 ---PAGE BREAK--- Figure 17. Najas guadalupensis (common water as abundance by two rake tosses. Najas guadalupensis (common water Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 22 ---PAGE BREAK--- Figure 18. Nitellopsis obtusa (starry stonewort) as abundance by two rake tosses. Nitellopsis obtusa (starry stonewort) Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 23 ---PAGE BREAK--- Figure 19. Potamogeton praelongus (white-stem pondweed) as abundance by two rake tosses. Potamogeton praelongus (white-stem pondweed) Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 24 ---PAGE BREAK--- Figure 20. Stuckenia pectinata (sago pondweed) as abundance by two rake tosses. Stuckenia pectinata (sago pondweed) Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 25 ---PAGE BREAK--- Figure 21. Stuckenia vaginata (sheathed pondweed) as abundance by two rake tosses. Stuckenia vaginata (sheathed pondweed) Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 26 ---PAGE BREAK--- Figure 22. Vallisneria americana (wild celery) as abundance by two rake tosses. Vallisneria americana (wild celery) Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). 27 ---PAGE BREAK--- Figure 23. Minor species as abundance by two rake tosses. Minor species Relative Plant Abundance Estimate no plants, trace plants 0.01 to 0.99 g / m2 dry weight), sparse plants 1.0 to 24.9 g / m2 dry weight), medium plants 25.0 to 99.9 g / m2 dry weight), dense plants 100 to 400+ g / m2 dry weight). odorata – white water lily Potamogeton crispus – curly-leaf pondweed Potamogeton foliosis – leafy pondweed Potamogeton pusillus – small pondweed Zannichellia palustris horned pondweed 28 ---PAGE BREAK--- Appendix Data 1. Wells College Bay rake-toss measurements recorded in 2016. The values for each plant species in each row is the biologist’s percentage estimate as part of the whole rake-toss…………….….30 Data 2. Wells College Bay rake-toss measurements recorded in 2016. Each rake-toss is recorded as either D = dense; M = medium; S = sparse; T = trace; or O = zero as an abundance rating. The only species recorded at these locations was Coordinates 1. Dates and locations of hydrilla discoveries in Wells College Bay during 2016, using True North and North American Datum 29 ---PAGE BREAK--- Data 1. Wells College Bay rake-toss measurements recorded in 2016. Each rake-toss is recorded as either D = dense; M = medium; S = sparse; T = trace; or O = zero as an abundance rating. The values for each plant species in each row is the biologist’s percentage estimate as part of the whole rake-toss. Date Sampled in 2016 NAD83 X cord EAST 18T NAD83 Y cord NORTH Depth 2016 Rake toss # Rake Abundance Rating Alisma gramineum demersum Chara vulgaris Elodea sp. Heteranthera dubia Hydrilla verticillata spicatum Najas flexilis Najas guadalupensis Nitellopsis obtusa odorata Potamogeton crispus Potamogeton foliosus Potamogeton praelongus Potamogeton pusillus Stuckenia pectinata Stuckenia vaginata Vallisneria americana Zannichellia palustris Total Species Non-Native Species Native Species 10/19 360750 4733425 0.7 1 S 10 10 0.01 20 50 0.01 0.01 0.01 10 9 2 7 10/19 360750 4733425 0.7 2 S 5 2 12 1 12 66 1 0.01 1 9 2 7 10/20 360725 4733425 0.7 1 S 5 2 10 38 39 0.01 5 0.01 1 9 2 7 10/20 360725 4733425 0.7 2 S 10 4 8 8 0.01 24 30 3 5 0.01 2 5 1 13 3 10 10/19 360775 4733450 1.0 1 T 5 15 1 63 1 15 6 3 3 10/19 360775 4733450 1.0 2 T 2 1 1 2 2 3 80 1 1 2 5 11 2 9 10/19 360750 4733450 1.3 1 S 0.01 0.01 10 5 50 20 5 0.01 0.01 10 10 3 7 10/19 360750 4733450 1.3 2 S 18 0.01 18 34 5 0.01 0.01 0.01 10 5 10 0.01 12 3 9 10/20 360725 4733450 1.7 1 T 34 1 5 10 35 5 10 7 2 5 10/20 360725 4733450 1.7 2 S 5 5 5 2 30 50 0.01 2 0.01 0.01 1 11 3 8 10/19 360775 4733475 1.5 1 T 1 1 67 30 1 5 2 3 10/19 360775 4733475 1.5 2 S 0.01 5 85 10 0.01 5 2 3 10/19 360750 4733475 1.7 1 M 0.01 10 15 55 5 10 5 7 2 5 10/19 360750 4733475 1.7 2 M 0.01 0.01 54 34 2 5 0.01 0.01 5 9 2 7 10/20 360725 4733475 1.8 1 M 2 50 0.01 30 0.01 0.01 18 7 1 6 10/20 360725 4733475 1.8 2 M 0.01 10 30 5 20 35 6 2 4 10/20 360800 4733500 1.2 1 T 5 20 5 5 60 5 6 2 4 10/20 360800 4733500 1.2 2 T 40 5 10 40 1 4 6 2 4 10/19 360775 4733500 1.5 1 T 1 3 65 30 1 5 2 3 10/19 360775 4733500 1.5 2 S 5 0.01 55 40 0.01 5 2 3 10/19 360750 4733500 1.7 1 M 50 50 0.01 0.01 0.01 5 2 3 10/19 360750 4733500 1.7 2 M 0.01 30 20 30 0.01 0.01 10 5 5 0.01 10 2 8 10/20 360725 4733500 1.9 1 S 0.01 0.01 35 50 15 5 2 3 10/20 360725 4733500 1.9 2 S 0.01 10 50 0.01 35 0.01 5 7 2 5 10/20 360800 4733525 1.5 1 T 5 15 5 55 13 5 1 1 8 2 6 10/20 360800 4733525 1.5 2 S 1 27 5 5 28 28 0.01 3 0.01 2 0.01 1 12 3 9 10/19 360775 4733525 1.6 1 M 0.01 1 46 46 0.01 2 5 7 2 5 10/19 360775 4733525 1.6 2 M 3 80 17 0.01 4 2 2 10/19 360750 4733525 1.8 1 S 0.01 0.01 40 30 0.01 0.01 30 7 2 5 10/19 360750 4733525 1.8 2 S 0.01 30 20 5 20 25 6 2 4 10/20 360725 4733525 2.0 1 M 90 5 5 0.01 4 2 2 10/20 360725 4733525 2.0 2 S 5 10 60 0.01 2 10 3 10 8 2 6 10/20 360800 4733550 1.5 1 T 3 15 10 49 10 2 1 10 8 2 6 10/20 360800 4733550 1.5 2 T 20 10 35 15 15 1 4 7 3 4 10/19 360775 4733550 1.7 1 M 0.01 0.01 45 45 7 3 0.01 7 2 5 10/19 360775 4733550 1.7 2 M 0.01 0.01 0.01 0.01 20 55 0.01 10 15 9 2 7 30 ---PAGE BREAK--- Date Sampled in 2016 NAD83 X cord EAST 18T NAD83 Y cord NORTH Depth 2016 Rake toss # Rake Abundance Rating Alisma gramineum demersum Chara vulgaris Elodea sp. Heteranthera dubia Hydrilla verticillata spicatum Najas flexilis Najas guadalupensis Nitellopsis obtusa odorata Potamogeton crispus Potamogeton foliosus Potamogeton praelongus Potamogeton pusillus Stuckenia pectinata Stuckenia vaginata Vallisneria americana Zannichellia palustris Total Species Non-Native Species Native Species 10/19 360750 4733550 2.0 1 S 100 1 1 0 10/19 360750 4733550 2.0 2 S 95 5 2 1 1 10/20 360725 4733550 2.5 1 M 2 38 37 8 5 10 6 2 4 10/20 360725 4733550 2.5 2 M 0.01 0.01 15 45 0.01 15 0.01 15 10 9 3 6 10/20 360800 4733575 1.5 1 S 10 4 40 25 1 15 5 0.01 8 2 6 10/20 360800 4733575 1.5 2 S 15 3 60 20 1 1 0.01 0.01 8 3 5 10/19 360775 4733575 1.8 1 M 0.01 40 20 0.01 20 20 0.01 7 2 5 10/19 360775 4733575 1.8 2 M 0.01 0.01 63 32 0.01 0.01 5 0.01 0.01 9 3 6 10/19 360750 4733575 2.5 1 D 80 10 0.01 5 0.01 5 6 2 4 10/19 360750 4733575 2.5 2 D 70 19 1 0.01 5 5 6 3 3 10/20 360725 4733575 2.9 1 M 0.01 0.01 3 40 50 2 2 3 0.01 9 3 6 10/20 360725 4733575 2.9 2 M 1 33 30 0.01 32 0.01 0.01 4 8 2 6 10/20 360800 4733600 1.6 1 T 5 10 70 10 4 1 6 3 3 10/20 360800 4733600 1.6 2 S 1 0.01 5 25 60 0.01 1 0.01 3 3 2 11 3 8 10/19 360775 4733600 2.0 1 M 5 0.01 20 15 20 20 20 7 2 5 10/19 360775 4733600 2.0 2 M 0.01 3 0.01 40 20 0.01 20 2 15 9 2 7 10/19 360750 4733600 2.7 1 S 100 1 1 0 10/19 360750 4733600 2.7 2 M 98 2 0.01 3 2 1 10/20 360725 4733600 3.5 1 S 10 1 48 0.01 1 30 10 7 3 4 10/20 360725 4733600 3.5 2 M 20 0.01 1 0.01 49 0.01 10 20 0.01 9 3 6 10/20 360800 4733625 1.7 1 T 5 12 5 3 75 5 3 2 10/20 360800 4733625 1.7 2 T 10 40 15 4 1 30 6 3 3 10/19 360775 4733625 2.3 1 M 3 2 5 10 60 20 6 2 4 10/19 360775 4733625 2.3 2 M 1 50 15 2 30 2 6 2 4 10/19 360750 4733625 3.0 1 M 70 20 0.01 0.01 0.01 10 6 2 4 10/19 360750 4733625 3.0 2 M 0.01 3 63 10 0.01 15 0.01 3 3 3 10 3 7 10/20 360725 4733625 4.0 1 M 5 0.01 0.01 45 0.01 0.01 5 10 2 33 10 3 7 10/20 360725 4733625 4.0 2 M 10 0.01 40 0.01 5 35 5 5 8 3 5 10/20 360800 4733650 1.5 1 S 0.01 8 10 10 40 2 30 7 2 5 10/20 360800 4733650 1.5 2 T 1 5 1 63 5 10 5 10 8 2 6 10/19 360775 4733650 2.5 1 M 0.01 0.01 10 50 0.01 10 10 5 15 9 2 7 10/19 360775 4733650 2.5 2 M 0.01 20 20 20 0.01 10 20 10 8 2 6 10/19 360750 4733650 3.1 1 M 0.01 79 5 0.01 1 10 5 7 3 4 10/19 360750 4733650 3.1 2 M 0.01 90 2 0.01 0.01 5 3 7 2 5 10/20 360725 4733650 3.9 1 S 20 35 5 5 35 5 1 4 10/20 360725 4733650 3.9 2 S 0.01 60 3 2 5 30 6 2 4 10/20 360800 4733675 1.9 1 T 1 5 50 2 6 1 35 7 2 5 10/20 360800 4733675 1.9 2 S 0.01 5 5 30 1 1 0.01 1 57 9 3 6 10/19 360775 4733675 2.6 1 M 2 58 10 0.01 20 5 5 7 2 5 10/19 360775 4733675 2.6 2 M 2 1 10 0.01 45 3 20 15 1 3 10 2 8 31 ---PAGE BREAK--- Date Sampled in 2016 NAD83 X cord EAST 18T NAD83 Y cord NORTH Depth 2016 Rake toss # Rake Abundance Rating Alisma gramineum demersum Chara vulgaris Elodea sp. Heteranthera dubia Hydrilla verticillata spicatum Najas flexilis Najas guadalupensis Nitellopsis obtusa odorata Potamogeton crispus Potamogeton foliosus Potamogeton praelongus Potamogeton pusillus Stuckenia pectinata Stuckenia vaginata Vallisneria americana Zannichellia palustris Total Species Non-Native Species Native Species 10/19 360750 4733675 3.2 1 M 100 0.01 0.01 0.01 4 2 2 10/19 360750 4733675 3.2 2 M 98 1 1 0.01 4 2 2 10/20 360725 4733675 4.2 1 S 35 1 0.01 0.01 15 5 1 41 2 9 4 5 10/20 360725 4733675 4.2 2 S 20 5 35 33 2 5 6 2 4 10/20 360800 4733700 2.0 1 T 5 95 2 1 1 10/20 360800 4733700 2.0 2 T 10 10 49 1 30 5 2 3 10/19 360775 4733700 2.7 1 M 2 45 8 0.01 45 0.01 6 3 3 10/19 360775 4733700 2.7 2 M 0.01 0.01 0.01 2 2 60 0.01 0.01 33 3 10 2 8 10/19 360750 4733700 3.7 1 M 0.01 8 0.01 20 0.01 0.01 5 50 15 2 10 3 7 10/19 360750 4733700 3.7 2 M 10 0.01 0.01 30 0.01 1 4 25 5 25 10 2 8 10/20 360725 4733700 4.5 1 T 5 25 20 50 4 1 3 10/20 360725 4733700 4.5 2 T 58 5 2 10 20 5 6 2 4 10/20 360800 4733725 2.1 1 S 45 5 0.01 50 4 1 3 10/20 360800 4733725 2.1 2 S 10 10 25 0.01 0.01 55 6 1 5 10/19 360775 4733725 3.1 1 M 3 2 0.01 0.01 68 2 0.01 10 3 2 10 11 3 8 10/19 360775 4733725 3.1 2 M 3 2 0.01 0.01 68 2 0.01 10 3 2 10 11 3 8 10/19 360750 4733725 4.0 1 D 5 70 0.01 0.01 10 10 5 7 1 6 10/19 360750 4733725 4.0 2 D 0.01 0.01 0.01 78 5 7 5 0.01 5 9 3 6 10/20 360725 4733725 4.5 1 S 60 0.01 0.01 0.01 30 0.01 10 7 2 5 10/20 360725 4733725 4.5 2 S 65 5 0.01 10 5 0.01 10 5 8 4 4 10/20 360800 4733750 1.7 1 S 60 40 2 1 1 10/20 360800 4733750 1.7 2 M 65 0.01 35 3 1 2 10/19 360775 4733750 3.3 1 D 0.01 0.01 95 0.01 0.01 0.01 5 0.01 0.01 9 2 7 10/19 360775 4733750 3.3 2 M 5 0.01 88 0.01 0.01 5 0.01 2 8 3 5 10/19 360750 4733750 3.8 1 S 5 10 30 20 30 5 6 2 4 10/19 360750 4733750 3.8 2 T 10 5 1 5 1 68 10 7 2 5 10/20 360725 4733750 4.6 1 T 94 5 1 3 1 2 10/20 360725 4733750 4.6 2 T 60 10 5 25 4 2 2 10/20 360800 4733775 1.7 1 T 70 30 2 1 1 10/20 360800 4733775 1.7 2 S 15 10 10 0.01 65 5 1 4 10/19 360775 4733775 3.3 1 D 0.01 92 3 1 3 1 6 2 4 10/19 360775 4733775 3.3 2 D 3 90 0.01 0.01 3 2 2 7 2 5 10/19 360750 4733775 4.0 1 S 5 0.01 25 5 55 10 6 2 4 10/19 360750 4733775 4.0 2 S 34 0.01 10 0.01 0.01 10 44 1 1 9 1 8 10/20 360725 4733775 4.6 1 T 50 50 2 1 1 10/20 360725 4733775 4.6 2 S 42 0.01 0.01 5 5 0.01 10 3 35 9 3 6 10/19 360800 4733800 1.9 1 T 60 40 2 1 1 10/19 360800 4733800 1.9 2 T 70 30 2 1 1 10/19 360775 4733800 3.3 1 M 0.01 90 10 3 1 2 10/19 360775 4733800 3.3 2 M 80 0.01 20 3 2 1 32 ---PAGE BREAK--- Date Sampled in 2016 NAD83 X cord EAST 18T NAD83 Y cord NORTH Depth 2016 Rake toss # Rake Abundance Rating Alisma gramineum demersum Chara vulgaris Elodea sp. Heteranthera dubia Hydrilla verticillata spicatum Najas flexilis Najas guadalupensis Nitellopsis obtusa odorata Potamogeton crispus Potamogeton foliosus Potamogeton praelongus Potamogeton pusillus Stuckenia pectinata Stuckenia vaginata Vallisneria americana Zannichellia palustris Total Species Non-Native Species Native Species 10/19 360750 4733800 4.1 1 M 40 0.01 10 0.01 0.01 0.01 30 0.01 20 9 2 7 10/19 360750 4733800 4.1 2 M 18 0.01 0.01 18 18 18 17 11 8 1 7 10/20 360725 4733800 4.7 1 T 20 1 79 3 1 2 10/20 360725 4733800 4.7 2 S 68 11 11 0.01 10 5 2 3 10/19 360800 4733825 1.8 1 T 20 80 2 1 1 10/19 360800 4733825 1.8 2 T 44 1 55 3 1 2 10/19 360775 4733825 3.2 1 D 5 90 0.01 5 4 2 2 10/19 360775 4733825 3.2 2 D 98 2 2 1 1 10/19 360750 4733825 4.1 1 S 30 20 0.01 5 20 20 5 0.01 8 2 6 10/19 360750 4733825 4.1 2 S 20 0.01 30 0.01 10 0.01 20 10 10 9 2 7 10/20 360725 4733825 4.5 1 S 100 0.01 0.01 0.01 0.01 5 2 3 10/20 360725 4733825 4.5 2 S 69 0.01 1 0.01 10 0.01 20 7 2 5 10/19 360800 4733850 1.7 1 T 10 90 2 1 1 10/19 360800 4733850 1.7 2 T 10 90 2 1 1 10/19 360775 4733850 3.2 1 D 10 80 0.01 5 0.01 5 6 2 4 10/19 360775 4733850 3.2 2 D 0.01 80 0.01 0.01 0.01 15 0.01 5 8 2 6 10/19 360750 4733850 3.9 1 M 15 27 0.01 5 28 10 15 7 2 5 10/19 360750 4733850 3.9 2 M 0.01 0.01 0.01 31 0.01 1 38 0.01 30 9 2 7 10/20 360725 4733850 4.6 1 S 40 5 0.01 0.01 10 40 5 7 2 5 10/20 360725 4733850 4.6 2 S 50 10 0.01 20 0.01 0.01 20 7 3 4 10/19 360825 4733875 0.5 1 T 98 2 2 0 2 10/19 360825 4733875 0.5 2 T 45 55 2 0 2 10/19 360800 4733875 1.7 1 T 4 40 1 55 4 1 3 10/19 360800 4733875 1.7 2 T 10 90 2 1 1 10/19 360775 4733875 2.7 1 M 85 0.01 0.01 10 5 5 2 3 10/19 360775 4733875 2.7 2 M 0.01 0.01 80 0.01 0.01 10 10 7 2 5 10/19 360750 4733875 4.0 1 S 5 20 0.01 55 15 5 6 2 4 10/19 360750 4733875 4.0 2 S 10 60 0.01 0.01 10 10 10 7 2 5 10/20 360725 4733875 4.6 1 M 0.01 20 1 39 0.01 5 35 7 2 5 10/20 360725 4733875 4.6 2 M 30 10 30 0.01 10 10 10 7 3 4 10/19 360800 4733900 1.5 1 S 5 2 50 2 41 5 1 4 10/19 360800 4733900 1.5 2 S 5 5 44 0.01 2 0.01 44 7 1 6 10/19 360775 4733900 2.5 1 M 0.01 69 1 10 0.01 20 6 1 5 10/19 360775 4733900 2.5 2 M 2 70 0.01 5 23 5 1 4 10/19 360750 4733900 3.8 1 M 10 0.01 40 0.01 10 20 20 7 2 5 10/19 360750 4733900 3.8 2 M 0.01 30 0.01 0.01 20 40 10 7 2 5 10/19 360725 4733900 4.7 1 T 100 1 0 1 10/19 360725 4733900 4.7 2 T 35 65 2 1 1 11 73 67 60 21 86 139 50 81 72 1 7 2 86 7 79 26 120 2 33 ---PAGE BREAK--- Data 2. Wells College Bay rake-toss measurements recorded in 2016. Each rake-toss is recorded as either D = dense; M = medium; S = sparse; T = trace; or O = zero as an abundance rating. Hydrilla was the only species recorded in the data below. Date Sampled in 2016 NAD83 X cord EAST 18T NAD83 Y cord NORTH Depth 2016 Rake toss # Rake Abundance Rating Alisma gramineum demersum Chara vulgaris Elodea sp. Heteranthera dubia Hydrilla verticillata spicatum Najas flexilis Najas guadalupensis Nitellopsis obtusa odorata Potamogeton crispus Potamogeton foliosus Potamogeton praelongus Potamogeton pusillus Stuckenia pectinata Stuckenia vaginata Vallisneria americana Zannichellia palustris 12/6 360700 4733400 0.5 1 T 12/6 360700 4733400 0.5 2 T 12/6 360650 4733400 0.5 1 S 12/6 360650 4733400 0.5 2 S 12/6 360700 4733425 1.3 1 M 12/6 360700 4733425 1.3 2 M 12/6 360675 4733425 0.5 1 T 12/6 360675 4733425 0.5 2 T 30 12/6 360650 4733425 2.5 1 M 12/6 360650 4733425 2.5 2 M 12/6 360700 4733450 1.7 1 M 0.01 12/6 360700 4733450 1.7 2 M 12/6 360675 4733450 1.5 1 M 12/6 360675 4733450 1.5 2 M 12/6 360700 4733475 2.0 1 M 20 12/6 360700 4733475 2.0 2 M 5 12/6 360675 4733475 2.0 1 M 12/6 360675 4733475 2.0 2 T 12/6 360700 4733500 2.4 1 M 2 12/6 360700 4733500 2.4 2 M 0.01 12/6 360675 4733500 2.5 1 M 0.01 12/6 360675 4733500 2.5 2 M 12/6 360700 4733525 2.5 1 M 2 12/6 360700 4733525 2.5 2 M 0.01 12/6 360675 4733525 3.0 1 T 1 12/6 360675 4733525 3.0 2 S 12/6 360700 4733550 3.0 1 S 12/6 360700 4733550 3.0 2 S 0.01 12/6 360675 4733550 3.5 1 S 12/6 360675 4733550 3.5 2 S 0.01 12/6 360700 4733575 3.5 1 S 0.01 12/6 360700 4733575 3.5 2 S 12/6 360675 4733575 3.5 1 T 5 12/6 360675 4733575 3.5 2 S 12/6 360700 4733600 3.5 1 S 0.01 12/6 360700 4733600 3.5 2 S 40 34 ---PAGE BREAK--- Date Sampled in 2016 NAD83 X cord EAST 18T NAD83 Y cord NORTH Depth 2016 Rake toss # Rake Abundance Rating Alisma gramineum demersum Chara vulgaris Elodea sp. Heteranthera dubia Hydrilla verticillata spicatum Najas flexilis Najas guadalupensis Nitellopsis obtusa odorata Potamogeton crispus Potamogeton foliosus Potamogeton praelongus Potamogeton pusillus Stuckenia pectinata Stuckenia vaginata Vallisneria americana Zannichellia palustris 12/6 360675 4733600 4.3 1 T 12/6 360675 4733600 4.3 2 T 12/6 360700 4733625 4.0 1 S 0.01 12/6 360700 4733625 4.0 2 S 0.01 12/6 360675 4733625 4.5 1 O 12/6 360675 4733625 4.5 2 T 12/6 360700 4733650 4.0 1 T 12/6 360700 4733650 4.0 2 S 1 12/6 360675 4733650 4.4 1 T 12/6 360675 4733650 4.4 2 T 12/6 360700 4733675 4.0 1 T 12/6 360700 4733675 4.0 2 T 12/6 360675 4733675 4.5 1 O 12/6 360675 4733675 4.5 2 T 12/6 360700 4733700 4.4 1 T 12/6 360700 4733700 4.4 2 T 12/6 360675 4733700 4.5 1 O 12/6 360675 4733700 4.5 2 T 12/6 360700 4733725 4.4 1 T 12/6 360700 4733725 4.4 2 T 12/6 360675 4733725 4.8 1 T 12/6 360675 4733725 4.8 2 T 5 12/6 360700 4733750 4.5 1 T 12/6 360700 4733750 4.5 2 T 12/6 360675 4733750 4.5 1 T 12/6 360675 4733750 4.5 2 T 12/6 360700 4733775 4.5 1 T 12/6 360700 4733775 4.5 2 T 12/6 360675 4733775 4.5 1 O 12/6 360675 4733775 4.5 2 T 2 12/6 360700 4733800 4.5 1 S 12/6 360700 4733800 4.5 2 S 12/6 360675 4733800 4.5 1 O 12/6 360675 4733800 4.5 2 O 12/6 360700 4733825 4.6 1 T 12/6 360700 4733825 4.6 2 T 12/6 360675 4733825 4.7 1 T 12/6 360675 4733825 4.7 2 T 12/6 360700 4733850 4.7 1 T 12/6 360700 4733850 4.7 2 T 35 ---PAGE BREAK--- Date Sampled in 2016 NAD83 X cord EAST 18T NAD83 Y cord NORTH Depth 2016 Rake toss # Rake Abundance Rating Alisma gramineum demersum Chara vulgaris Elodea sp. Heteranthera dubia Hydrilla verticillata spicatum Najas flexilis Najas guadalupensis Nitellopsis obtusa odorata Potamogeton crispus Potamogeton foliosus Potamogeton praelongus Potamogeton pusillus Stuckenia pectinata Stuckenia vaginata Vallisneria americana Zannichellia palustris 12/6 360675 4733850 4.9 1 T 12/6 360675 4733850 4.9 2 O 12/6 360700 4733875 4.5 1 T 12/6 360700 4733875 4.5 2 S 0.01 12/6 360675 4733875 4.9 1 O 12/6 360675 4733875 4.9 2 T 12/6 360700 4733900 4.5 1 T 12/6 360700 4733900 4.5 2 T 12/6 360675 4733900 5.0 1 T 12/6 360675 4733900 5.0 2 O 12/6 360775 4733925 1.5 1 D 12/6 360775 4733925 1.5 2 M 12/6 360750 4733925 3.1 1 M 12/6 360750 4733925 3.1 2 S 12/6 360725 4733925 4.0 1 S 12/6 360725 4733925 4.0 2 S 12/6 360700 4733925 4.5 1 T 12/6 360700 4733925 4.5 2 T 12/6 360775 4733950 1.6 1 M 12/6 360775 4733950 1.6 2 M 12/6 360750 4733950 3.0 1 S 12/6 360750 4733950 3.0 2 S 12/6 360725 4733950 4.0 1 T 12/6 360725 4733950 4.0 2 T 12/6 360700 4733950 4.5 1 O 12/6 360700 4733950 4.5 2 T 22 36 ---PAGE BREAK--- Coordinates 1. Dates and locations of hydrilla discoveries in Wells College Bay in 2016, using True North and North American Datum 1983. Date UTM X coord EAST UTM Y coord North Date UTM X coord EAST UTM Y coord North 10/19 360750 4733425 12/6 360700 4733575 10/20 360725 4733425 12/6 360675 4733575 12/6 360675 4733425 10/20 360800 4733600 10/19 360775 4733450 10/19 360775 4733600 10/19 360750 4733450 10/19 360750 4733600 10/20 360725 4733450 10/20 360725 4733600 12/6 360700 4733450 12/6 360700 4733600 10/19 360775 4733475 10/20 360800 4733625 10/19 360750 4733475 10/19 360775 4733625 10/20 360725 4733475 10/19 360750 4733625 12/6 360700 4733475 10/20 360725 4733625 10/20 360800 4733500 12/6 360700 4733625 10/19 360775 4733500 10/20 360800 4733650 10/19 360750 4733500 10/19 360775 4733650 10/20 360725 4733500 10/19 360750 4733650 12/6 360700 4733500 12/6 360700 4733650 12/6 360675 4733500 10/20 360800 4733675 10/20 360800 4733525 10/19 360775 4733675 10/19 360775 4733525 10/20 360725 4733675 10/19 360750 4733525 10/20 360800 4733700 10/20 360725 4733525 10/19 360775 4733700 12/6 360700 4733525 10/19 360750 4733700 12/6 360675 4733525 10/19 360775 4733725 10/20 360800 4733550 10/19 360750 4733725 10/19 360775 4733550 10/20 360725 4733725 10/19 360750 4733550 12/6 360675 4733725 10/20 360725 4733550 10/19 360775 4733750 12/6 360700 4733550 10/20 360725 4733775 12/6 360675 4733550 12/6 360675 4733775 10/20 360800 4733575 10/20 360725 4733800 10/19 360775 4733575 10/20 360725 4733825 10/19 360750 4733575 10/20 360725 4733850 10/20 360725 4733575 12/6 360700 4733875 Wells College Bay Wells College Bay 37 ---PAGE BREAK--- References Borman, R. Korth, J. Temte. 1999. Through the Looking Glass: A Field Guide to Aquatic Plants. Wisconsin Lakes Partnership, University of Wisconsin-Extension. Reindl Printing, Inc. Merrill, WI. pp. 1-238. Crow, G. E. and C. B. Hellquist. 2000. Aquatic and Wetland Plants of Northeastern North America. The University of Wisconsin Press. 2 volumes. pp. 1-480; 1-400. Madsen, J. D. 1999. Point and line intercept methods for aquatic plant management. APCRP Technical Notes Collection (TN APCRP-M1-02), U.S. Army Engineer Research and Development Center, Vicksburg, MS. pp. 1-16. ADA361270 Johnson, R. L. 2008. Aquatic Plant and Aquatic Macroinvertebrate Monitoring in Chautauqua Lake during 2007. Racine-Johnson Aquatic Ecologists, 1185 Ellis Hollow Road, Ithaca, NY 14850. pp. 1-49. Johnson, R. L. 2013. Cayuga Lake and Cayuga Inlet Aquatic Plant Community 2012. Racine-Johnson Aquatic Ecologists, 1185 Ellis Hollow Road, Ithaca, NY 14850. pp. 1-179. Johnson, R. L. 2014. 2013 Monitoring Report of the Cayuga Inlet and Southern Cayuga Lake Monoecious Hydrilla Eradication Project. Racine-Johnson Aquatic Ecologists, 1185 Ellis Hollow Road, Ithaca, NY 14850. pp. 1-272. Johnson, R. L. 2015. 2014 Monitoring Report of the Cayuga Inlet and Southern Cayuga Lake Monoecious Hydrilla Eradication Project. Racine-Johnson Aquatic Ecologists, 1185 Ellis Hollow Road, Ithaca, NY 14850. pp. 1-271. Johnson, R. L. 2016. 2015 Monitoring Report of the Cayuga Inlet and Southern Cayuga Lake Monoecious Hydrilla Eradication Project. Racine-Johnson Aquatic Ecologists, 1185 Ellis Hollow Road, Ithaca, NY 14850. pp. 1-299. Racine-Johnson Aquatic Ecologists Erica M. Herman Robert L. Johnson Mikhail S. Kern Mihai C. Miroiu Melanie K. Rooney 38