The Fish Sustainability Index (FSI) combines scientific, and local knowledge to assess the health of mooneye in Alberta.
Mooneye FSI Maps
Adult Density (Current and Historic)
Stocked lake populations are denoted with a circle. Please note that data reliability is not currently displayed in these figures.
Habitat and Overharvest Protection Needs
Please note that data reliability is not currently displayed in these figures.
The complete FSI spatial data layers WinZip file package can be downloaded at:
Mooneye Population Status
In summary, mooneye are a recent arrival in Alberta rivers, apparently naturally expanding their range and slightly increasing their numbers. One population in
the Battle River appears to be declining because of habitat loss (poor water quality). Mooneye are commonly misidentified as goldeye, and monitoring for either
species has not been consistent. Consequently, our conclusions are uncertain.
Historically, mooneye were not reported in Alberta until the 1970s, when occasional catches of mooneye began to be made in most of the rivers of the Saskatchewan
River system (i.e., North Saskatchewan, Red Deer, Battle, Bow, Oldman, and South Saskatchewan).
Overall, abundance has continued to slowly increase, but with most populations still at low to moderate abundance. The mooneye that formed an initial population
in the Battle River appear to have suffered the same fate as goldeye in this degraded watershed and are nearly lost.
Threats to Sustainability
The main threats to sustainability of mooneye appear to be:
- Poor water quality in the Battle River, especially low oxygen levels associated with nutrients and run-off from intensive land use, is likely a main cause of
this population’s decline.
- Large dams near the headwaters of mainstem rivers like the North Saskatchewan, Red Deer and Bow rivers may have resulted in changes to river habitat that mooneye
preferred (e.g., less glacial silt, lower summer flows), allowing them to move into the Alberta portions of their natural range. Dams lower in the river systems,
however, would block migrations of this highly migratory fish.
- Mooneye may have been overfished in certain locations (e.g., near the cities of Edmonton and Red Deer) but overfishing by angling does not appear to be a widespread
- As with goldeye, monitoring mooneye in Alberta has neither been consistent or effective. Migratory and schooling, mooneye pose great difficulties to accurate
monitoring. The status of mooneye and our conclusions are therefore quite uncertain. Efficient techniques to assess the abundance and population structure of mooneye
must be developed and implemented.
- Evaluate current regulations to ensure they align with the status of mooneye stocks.
- Understanding the effects of dams, water use, and land use on Alberta’s large rivers and fishes is complex, and continued work is needed to achieve our goals
of sustaining healthy populations of river fish such as mooneye.
Updated: Dec 9, 2015