ODFW conducts creel surveys at Diamond Lake to interview anglers about their catch and harvest to assess the lake’s fishery. A statistically based sample of days is randomly selected each summer to survey enough weekdays and weekends throughout the fishing season to estimate total catch and harvest at the lake each year.
During creel surveys at the lake, staff can also get lengths of fish to assess fish growth rates. Creel surveyors are also able to answer questions on fishing, regulations, and conduct boat inspections to look for invasive species. Anglers may be asked if surveyors can sample stomachs from fish harvested to look at trout diets in the lake.
These surveys help ODFW estimate total anglers that fish the lake and total harvest of fish out of the lake.
Historic angler trips and total catch per year (pdf)