Offshore Wind Power Projects in the Great Lakes - Ministry of ...

Offshore wind power projects in the Great Lakes: Background and science considerations for fish and fish habitat
and nocturnal reef inhabitants (e.g. Creque et al. 2006; Kevern et al. 1985). More recently, the
use of hydroacoustic methods has been promoted as an approach to improve the quantification of
fish stocks near introduced hard structures (Hvidt et al. 2006; see section below).
In addition to assessing the fish aggregating effect of wind turbines, it would also be useful to
determine whether local fish species actually use the newly created habitat for foraging or
spawning activities. This should certainly be a focus of investigation if turbine foundations and
scour protecting materials are designed specifically to enhance fish habitat so that proponents
can evaluate the degree of success of their efforts. Evidence of spawning around wind turbines
can most definitively be obtained if eggs or fry are found. At artificial reefs in the Great Lakes,
evidence for spawning has been obtained from visual searches conducted by scuba divers during
known spawning or egg hatching periods, by vacuum pumping rocky crevices to find and collect
eggs, by deploying and checking fry traps around the area, or even using plankton nets to trawl
for nearby fry (Kevern et al. 1985). Currently, however, the use of egg nets set and retrieved by
scuba divers is the most commonly employed method for evaluating the use of reefs as spawning
habitat (Fitzsimons personal communication). For deeper water reefs, remotely operated
electrofishers with video and gang-line deployment of deepwater egg traps have also proven
effective to evaluate lake trout reproductive activity (Riley et al. 2010). With regards to assessing
foraging use or feeding behaviour of fish associated with wind turbine structures, the stomach
contents of fish could be compared with reef epifauna or prey items or, alternatively, using lipid
analysis or isotopic techniques (Linley et al. 2007). Finally, site fidelity or residency times of
different fish species could be assessed using acoustic telemetry or mark-recapture studies
(Linley et al. 2007), which could prove useful to determine whether or not species like lake trout
are consistently attracted to spawn at these novel habitats.
5.8 Common approaches for monitoring fish populations
Above we reviewed several examples of specific monitoring approaches that could be employed
to assess some of the potential impacts associated with wind power projects in the Great Lakes.
While we have touched upon several of them already, in the next section we will describe several
recommended monitoring protocols or survey techniques commonly employed by individuals or
institutions engaged in fish community surveys within the Great Lakes, and highlight examples
of where they have been used in baseline or effects monitoring programmes for wind power
Aquatic Research and Development Section 69