Fish Program
The IISD-ELA fish research program covers all aspects of fish ecology, including population and community abundance and structure, behaviour, food web interactions, contaminants, and energy transfer
The fish program at IISD-ELA is responsible for monitoring the general health and well-being of fish species, including natural variability and responses to experimental manipulation. Fish do not always respond immediately to external influences, so there is a strong need for long-term monitoring to see how effects of whole ecosystem experiments cascade through the food web and ultimately affect fish feeding at specific trophic levels. We monitor all fish species present in lakes at IISD-ELA, including sport fish such as lake trout, northern pike, yellow perch, and lake whitefish, benthic feeding fish such as white sucker, and forage and minnow species, including fathead minnows and a variety of dace.
During the spring and fall seasons we use mark-recapture techniques to estimate population abundance and structure in many of the IISD-ELA lakes. These estimates are used as background information for experiments and as baseline information for future studies. These data illustrate natural variability in fish populations, and provide the backbone for fish research at IISD-ELA.
We also study the effects of a wide-range of environmental perturbations on fish, including effects on growth, survival, condition, and behaviour. Contaminants, physical changes to the ecosystem, introduction of competing species, and other impacts are all studied at IISD-ELA. However, our lakes and their resident fish populations are small, so it is essential that we treat the animals with care. We use non-lethal methods to assess things like contaminant concentrations, stable isotopes of carbon and nitrogen, stress markers, and diet preferences, among others and we set a strong focus on using and developing new non-lethal sampling procedures.
Some of our work, like populations monitoring, involves directly handling fish. However, for more than a decade, researchers at IISD-ELA have also been able to employ a more hands-off approach by tracking fish remotely using acoustic telemetry systems. Acoustic transmitters are implanted in the gut cavity of fish with a brief surgical procedure (see a video here). These transmitters allow us to continuously monitor individual fish locations in a number of IISD-ELA lakes, providing answers to important questions like habitat requirements, space use, activity levels, and winter behaviour.
Types of data collected in this program:
- Biological, morphometric and general health measurements (such as length, weight and condition)
- Population abundance estimates (based on mark-recapture) and catch per unit effort
- Age data and aging structures
- Acoustic telemetry (spatial, depth, activity, temperature)
- Food web carbon and nitrogen stable isotopes
- Diet/gut contents
- Mercury concentrations
- Other contaminants (related to specific experiments)
- Hydroacoustic surveys
See our data request page for more information.