The Bottom of the Web
Everything in this lake eats something, and at the bottom of that the chain runs out into things too small to see. Since 1992 a boat has gone to fifteen fixed stations about ten times a year and measured what is in the water. The chemistry is still being measured. The plankton is not.
This is the other half of What Lives in It. That page can say what is in the lake and cannot say how much of anything there is, because an occurrence record counts observers. This one counts organisms and water chemistry, at known places, on a known schedule — and its interest is as much in when the counting stopped as in what it found.
What was measured, and until when
Every series in the program, as a bar from its first year to its last. The chemistry runs to the present. The two biological series do not.
Where in the lake
The lake-wide line below is an average of fifteen stations, and the stations are not one lake. Missisquoi Bay and the Main Lake sit at opposite ends of every scale the program measures. Pick a year and a measure; the color is fixed across the whole record, so a bright station means the same thing in 1994 as in 2024.
How much algae there is
Chlorophyll-a, the pigment assay, as the mean of the station means for each year. It answers how much, and it is the series that survived.
And the phosphorus that feeds it
Does any of it predict a bloom?
This site already carries thirteen seasons of the Vermont Health Department's cyanobacteria reports, on Summers of Blooms. Here it is set beside the chemistry. Each point below is one segment in one year: the monitoring stations' mean against the share of that segment's volunteer reports filed at alert level.
Which algae — ten years of it
Net phytoplankton biovolume by division, 2006 to 2015. This is the series that can tell a diatom from a cyanobacterium, and it is the one that stopped.
And what was eating them — nothing to show
The program's own parameter table offers four zooplankton series from the New York lab, 1993 to 2013: total density, copepods, cladocerans, rotifers. The query tool returns no rows for any of them, at any of the fifteen stations, over any span — asked through its own form and through a request built by hand.