Aquatic Plant Survey

About Prospect Lake:

The W̱SÁSENEĆ name for Prospect Lake is XOĆE EṮ W̱SÁSENEĆ – The lake of Little Saanich Mountain” J,SIṈTEN (John Elliott):
There are four lakes, Prospect, Maltby, Killarney and Durrance within the 2,344 hectare Tod Creek Watershed
Prospect Lake is at an elevation of 47 m above sea level and is the headwaters of Tod Creek
Maximim Depth: 14 m
Mean Depth: 6.7 m
Surface Area: 0.6 km2
Shoreline Perimeter: 4.7 km

About the Annual Aquatic Plant Survey:

First aquatic plant survey conducted by P Warrington – 1980
Second survey with Dr Angeline Tilmans, University of Victoria – 2013
Aquatic Plant identification workshop instructed by Dr Rick Nordin – 2015
First Friends of Tod Creek Watershed Aquatic Plant Survey (eight sites) – 2015
Consecutive Plant Surveys – 2015 to 2023
*First sample of Myrophyllum spicatum, Eurasian water milfoil, at two sites in 2019
*Eurasian water milfoil found in all sites 2020
*Eurasian milfoil dominant plant in most sites 2022

Poster Presentation and Lakeside Demonstration

Presentation at Power To Be on Sept 24th 2023

Photo by: Winona Pugh

Cropped from photo: details about the lake and plant survey:

Lakeside Demo

Winona Pugh and Lori James Derry. Photo by: Carmel Thomson
Winona demonstrates our simple plant collection method: after the floating barge arrives at 1 of our 8 Sites around the lake,
a rope marker [tied off in knotted measurements] tells us where to gather plants at a depth of 2, 4 & 6 meters.

Here she tosses a rake, which comes to rest on the determined depth, then is dredged up with the aquatic plants.
Still photo from video by: Carmel Thomson
Photo by: Lori James Derry
Photo by: Lori James Derry
After a dearth of rain this summer, a storm was predicted for the day of our demo. Everything was weighted down with rocks. Photo by: Carmel Thomson
Photo by: Lori James Derry
The equipment is laid out here in order of processing.
Photo by: Carmel Thomson
Photo by: Carmel Thomson
Photo by: Carmel Thomson
Photo by: Lori James Derry
Left to Right:
the bathymetric map of Prospect Lake, showing our 8 Sites, plus depth in meters; below that is a bin of plant samples;
all set against the square meter density measuring mat; on the right lower quadrant of the mat,
we always display the site & depth before photographing [ie Site 2: 4 meters];
the labels are drying in the bin to the right; second bin right is our Aquatic Plant Identification Guide;
to the top right of the mat are examples of how we enter the data onto our website, complete with plant IDs, and photos;
right of the data board is a screen grab of our website, plus our QR code for quick access;
and finally, iNaturalist info, one of our data destinations.
Photo by: Lori James Derry
Bathymetric map, 8 Sites marked off.
To the left of Site 4 you can see the three depth lines of 2, 4 & 6 meters, delineations that circle the lake.
Above Site 8 is the island.
Photo by: Lori James Derry
The plants are teased out, spread onto a square meter mat for a density measurement: Sparse [under 5 plants], Moderate [5 – 10 plants], and Dense [0ver 10].
We save good examples of individual plants for ID, and photographing.
Photo by: Lori James Derry
On the right lower quadrant of the mat, we always display the site & depth before photographing [ie Site 2: 4 meters].
Photo by: Lori James Derry
Site labels; and top left are the real-time plant IDs, later entered onto the website.
Photo by: Lori James Derry
Photo by: Lori James Derry
How we enter our data onto website; and a photo progression toward a standardized measuring tool
[ie no more ziplocks, or linen napkins of undetermined sizes].
Photo by: Lori James Derry
Bottom left: our Plant ID guide; above is the screen grab of our website Home Page, plus our QR code;
and right is the iNaturalist guide.
Photo by: Lori James Derry

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