Ship Ballast Studies
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Greater than 90% of ships entering the Great Lakes between 1995-1998 carried No declarable Ballast On Board (i.e. they declared NOBOB status).  These ships typically carry about 40 tonnes (40,000L) of unpumpable ballast water and 10 tonnes of residual sediment.  The water may contain live organisms, while the sediment may contain huge numbers of resting stages (e.g. cysts, ephippia, resting eggs).  NOBOB vessels will typically visit a series of ports on the Great Lakes, at which they discharge cargo and load Great Lakes ballast water.  At their final port of call (ca. 70% of the time this is another Great Lakes port), they discharge the Great Lakes ballast water.  During the period between initial uptake of ballast water and its release into the Great Lakes, live NIS animals may have reproduced and resting eggs may have hatched.

Doctoral student Sarah Bailey conducted a series of studies to:

1) quantify the amounts of water and sediment in NOBOB ships entering the Great Lakes;
2) quantify the diversity and abundance of resting eggs of invertebrate species in these ships;
3) Experimentally test the conditions under which these eggs will hatch in the laboratory  and in situ (on board the vessels);
4) Determining the effects of egg burial, temperature, and salinity on hatch rates in lab studies;
5) Assessing whether exposure of eggs of freshwater  species to salt water will reduce the subsequent viability of the eggs.

Sarah's work has been published in a variety of journals including Limnology and Oceanography, Freshwater B