Emily Runnells and Meghan Brown With Thanks To: ~Field and Lab Help: The Brown and Halfman Lab Crews ~Funding: Senator Nozzolio and the State of NY, and Hobart and William Smith

Owasco Lake Relative to other Finger Lakes –Large watershed –Small volume –Poor water quality Recently,phytoplankton blooms and macrophyte growth increasingly common 2007 ~2 μg/L Chl a Chlorophyll Asterionella

Why Monitor with Zooplankton? Phytoplankton Carnivorous Zooplankton Forage fish Sport fish Herbivorous Zooplankton Nutrients

Measures of Productivity LOWHIGH Secchi Transparency Several meters, usually into the hypolimnion. Few meters, in the epilimnion. Chlorophyll aLessMore Zooplankton Low density Selective feeders High density Tolerant of lower quality food

The Questions Asked: Does zooplankton composition data agree with other data measuring productivity in Owasco Lake? Does zooplankton composition analysis indicate increased productivity of Owasco Lake? ? ==

Sampling Secchi Zooplankton Chl a

Low Productivity High Productivity May June July Gannon Index = Σ Calanoid Σ (Cyclopoid + Cladocerans)

Station 1: Productivity Measures Gannon Secchi Depth (m) Chl a (μg/L) May June July Σ Calanoid Σ ( Cyclopoid + Cladocerans)

Station 2: Productivity Measures Chl a (μg/L) Secchi Depth (m) Gannon May June July Σ Calanoid Σ ( Cyclopoid + Cladocerans)

And so…. Does zooplankton composition data agree with other data measuring productivity in Owasco Lake? Yes and No Sometimes agreement Not consistently one parameter that is out of line

Does zooplankton composition analysis indicate increased productivity of Owasco Lake? ►Yes: May and July ►Overall lake has moderate productivity More Bosmina than Daphnia More cyclopoid than calanoid