RAP
xiii. Degradation of Plankton Populations
Below are the 14 Beneficial Use Impairments (BUIs) in the Hamilton Harbour Area of Concern. BUIs identify specific problems in the Harbour that result in limited use of the area and are caused by unfavourable changes to the chemical, biological, or physical makeup of the water. These BUIs must be remediated (using the RAP) in order to delist Hamilton Harbour as an Area of Concern.
BUI xiii Degradation of Phytoplankton and Zooplankton Populations
Status: Requires Further Assessment
What was the original problem? The concern across many Area Of Concerns was various effluents entering the water, particularly phosphorous from sewage treatment plants and industrial contaminants, were creating chemically driven, unhealthy populations. Hamilton Harbour phytoplankton and zooplankton communities were described as being reflective of a eutrophic system due to their high numbers and their high level of activity. Studies of the toxicity of Hamilton Harbour water to phytoplankton and zooplankton indicated no unusual toxicity, but the situation was under review.Listing Guideline: When phytoplankton or zooplankton community structure significantly diverges from unimpacted control sites of comparable physical and chemical characteristics. In addition, this use will be considered impaired when relevant, field-validated, phytoplankton or zooplankton bioassays (e.g. Ceriodaphnia; algal fractionation bioassays) with appropriate quality assurance/quality controls confirm toxicity in ambient waters.
Delisting Guideline: When phytoplankton and zooplankton community structure does not significantly diverge from unimpacted control sites of comparable physical and chemical characteristics.
What Has Been Done?
- Various projects aim to move the Harbour from a eutrophic state towards a mesotrophic state (Wastewater Treatment Plant upgrades, Combined Sewer Overflow containment, improved industrial discharges, watershed stewardship, etc.)
How Are Things Today?
- The Ontario Ministry Of the Environment has sampled Hamilton Harbour as part of their Great Lakes Index-Reference Station Monitoring Program which cycles every three years, three times/year. Phytoplankton and zooplankton data are part of this data set; however, there has been no money to analyze the samples until now
- Department of Fisheries and Oceans Great Lakes Laboratory for Fisheries and Aquatic Sciences has conducted biweekly surveys of phytoplankton, zooplankton, microbial and benthic communities at 2 index stations from 2002 – 2009 with comprehensive spatial surveys in 2006
What Still Needs To Happen?
- In 2011, Environment Canada arranged for the counting and identification of the seasonal Ontario Ministry Of the Environment phytoplankton and zooplankton samples. The Department of Fisheries and Oceans will interpret this data once the counting and identification are completed
- From 2012-2015, the Department of Fisheries and Oceans will be combining data from a number of Lake Ontario sites to develop a reference condition data set for a mesotrophic embayment. This data set is needed as there is not one ideal reference site for Hamilton Harbour to use for comparison. New sites will be identified and sampled to augment Ontario Ministry Of the Environment and Department of Fisheries and Oceans data sets
When Will The Status Change?
- A status change from “requires further assessment” is expected around 2015 after an evaluation of all lines of evidence by the Hamilton Harbour RAP Technical Team
For full information on BUI xiii:
Photo Credit: Royal Botanical Gardens
