Beneficial Use Impairment #6
BUI #6 - Degradation of benthos
Status - Impaired - undergoing redesignation
Benthic Macroinvertebrates or benthos are small creatures that live in the sediment on the bottom of lakes, rivers and streams. They include aquatic insects, snails, clams and worms. The variety and abundance of each species provide indicators of water quality. Some species are tolerant of poor water quality, while others require good water quality to survive.
In the early 1990s, benthos in the Bay were identified as degraded due to a lack of species variety. Poor water quality restricted the species of benthos that could survive in the Bay of Quinte. However, over the years, there have been improvements to the water quality in the Bay.
As well, there have been historic land use changes in the ecosystem - changing the land cover from forests to urban and rural land uses - which changed the of sediment base of the Bay from gravelly to silty.
Also, the introduction of invasive species like, zebra mussels and round goby have impacted the benthic communities.
These are permanent changes, that not only affected the Bay of Quinte but the whole Great Lakes basin.
The historic land use changes and the introduction of invasive species continue to influence the composition of the benthic communities in the Bay. These changes have reduced the diversity of benthos in the Bay of Quinte, however, there are still species in the Bay that require good water quality to survive.
This environmental challenge has met all the scientific criteria outlined in the Remedial Action Plan.
Here is the final report.Degradation of benthos - underwater bugs - Final Report