Plankton assemblages in Canadian Shield lakes are currently in a
state of dramatic flux, but we cannot explain these changes by simply
looking at environmental co-variations, eg. changes in lake physics,
chemistry or fisheries assemblages that may be correlated with
zooplankton changes. The problem is not simply that correlation may not
connote causation, rather it is that there are so many significant
correlations. To identify the cause or causes of these changes I have
constructed the FLAMES lab at Dorset, in collaboration with the Ontario
Ministry of the Environment. With the facilities of this lab we can
determine which among the logical possibilities are the actual
explanations for ecological change on the Shield.
In the FLAMES lab we maintain many cultures of zooplankton isolated
from central Ontario lakes, and they are maintained in fully-defined
media modeled after the chemistry of Dorset-area lakes that support
diverse plankton assemblages. The lab is designed to allow us to test
(in batch or continuous flow mode) the separate and joint effects of
multiple ecological stressors on zooplankton in soft-water across a
range of temperatures. Dallas Linley, the FLAMES lab supervisor,
maintains the lab in a state of readiness for the use of multiple
students and researchers. All our media are prepared from scratch
starting with extremely pure chemical-free water. The experiments are
normally conducted across a range of temperatures, as climate change is
a reality in the area. There is lots of room for students and
collaborating scientists to work, as the foot print of the lab is a
roomy 2700 square feet. Here are some examples of recent or ongoing work
being conducted in the FLAMES lab:
1. Dawn Ashforth (MSc 2006 York University) determined how Ca
thresholds affecting population parameters of Daphnia pulex would be
affected by changes in temperature and food availability.
2. Dallas Linley (FLAMES lab supervisor) identified Ca thresholds
affecting population parameters of 4 daphniid species in softwater.
3. Dr. Howard Riessen (SUNY Collge Buffalo) is identifying the
fitness tradeoffs of size at maturity, and production of neck teeth of
differently sized daphniid species in response to different sized
invertebrate predators.
4. Martha Celis-Salgado (PhD student, York University) is quantifying
the affects of Cu and Ni, alone and in mixtures, on Daphnia species at
various temperatures and Ca levels in order to explain the delayed
recovery of Cladocera in comparison with Copepoda in Sudbury lake.
5. Natalie Kim (MSc student, York University) is quantifying the
effects of light, temperature and pH on probability of establishment
success of the spiny water flea, Bythotrephes.
6. Christine Gibson (incoming MSc student, York Unviversity) will be
looking at the effects of pH and temperature on Ca thresholds of various
species of daphniids in soft-water media.
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