Which technique for gathering data (observational study or experiment) do you think was used in the following studies? (a) The Colorado Division of Wildlife netted and released 774 fish at Quincy Reservoir. There were 219 perch, 315 blue gill, 83 pike, and 157 rainbow trout. This is an observational study because observations and measurements of individuals are conducted in a way that doesn't change the response or the variable being measured. This is an observational study because a treatment was deliberately imposed on the individuals in order to observe a possible change in the response or variable being measured. This is an experiment because a treatment was deliberately imposed on the individuals in order to observe a possible change in the response or variable being measured. This is an experiment because observations and measurements of individuals are conducted in a way that doesn't change the response or the variable being measured