Selects specific ages and ranges of ages among a species' cohorts for harvesting.
        public void Init()
        {
            abiebals = TestUtil.Species.SampleDataset["abiebals"];

            selector_25_50_75_100to200_300to500 = CreateSelector(25, 50, 75, null,
                                                                 100, 200,
                                                                 300, 500);
            selector_2to99_250 = CreateSelector(250, null,
                                                2, 99);

            isHarvested = new SpeciesCohortBoolArray();
        }
        //---------------------------------------------------------------------

        private void SelectCohorts(ISpeciesCohorts            cohorts,
                                   SpecificAgesCohortSelector selector)
        {
            isHarvested.SetAllFalse(cohorts.Count);
            selector.SelectCohorts(cohorts, isHarvested);
        }