The Peter G. Meier Water Quality Survey

Black Pond is situated in a hardwood forest north of the Leslie Science Center, Ann Arbor, Michigan. Perched above the surrounding countryside, one walks up a winding log-lined path to reach the pool.

Black Pond was added to the Water Quality Survey in the spring of 2010 and we are currently establishing base line data for the site. Notable among the pond's physico-chemical parameters is a relatively low capacity to conduct an electric current. This capacity is called specific conductance and in March of 2010 we recorded a value of just 117 µS for that parameter. The pond water's low capacity to conduct an electrical current is essentially due to a lack of inorganic ions on the one hand, and to an abundance of organic compounds on the other hand.

Aquatic Macroinvertebrates

In our collection made 27 March 2010, the abundance and diversity of crustaceans was particularly noteworthy. The back-swimming fairy shrimp were common in the samples, as were seed shrimp (Ostracoda), scuds (Amphipoda), water fleas (Copepoda), and aquatic sow bugs (Isopoda).

The fairy shrimp are a late-winter, early spring phenomenon: their abundance is short-lived, and they spend most of the year as resting eggs in the debris at the bottom of the pond.

During the sorting, I was startled by the appearance of macrobdella leech, a red-striped specimen that had secreted itself to the rim of the sorting pan and had extended its body above the rim about 15 cm (~6.0 in). It was searching back and forth and I nearly grasped the creature as I was about to lift the pan while glancing at a specimen under the dissecting scope.