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I I I I I I I I I I I I I I I I I I I . TRANSPORTATION PROCEDURES Half-gallon thermal jugs (Rubbermaid Incorporated, Wooster, OR) were used to transport one shipment of 16-24 hour-old fertilized pikeminnow eggs from DNFH to the FRH. Eggs in water were poured into the water-filled jugs. Excess water flowed over the top of the jug and eggs sank to the bottom of the containers. Jugs were capped and placed into a cardboard box for . transportation. Eggs were in these containers approximately 8 hours and water temperature (600 F) stayed constant. INCUBATORS V ertical- Tray Incubators (Heath Incubators) Standard vertical incubators (Heath Tray, Marl Source, Tacoma, W A) are designed for salmonid eggs (@ 6,000Ilb) and must be modified for the smaller pikeminnow eggs (@60,000/lb) and newly hatched fry. Because pikeminnow fry are small enough to go through the standard size mesh screen (16 squaresflllch) on an egg tray, a vertical incubator was modified so that all the water drained into a screened catch basin below the incubator. The catch basin had a smaller screen size (cloth mosquito netting with 30 squares/inch) that prevented newly hatched fry from escaping. The FRH used this modified Heath incubator system only once to incubate and hatch one large lot of pike minnow (150,000 eggs divided into two trays). It is recommended that trays have smaller screen size (@30 squaresfmch or smaller) installed to reduce escapement offry. Extra caution needs to be taken when using smaller mesh screens to make sure that they are always clean to prevent fouling of the water and potential mortality of eggs and/or fry. Due to possible escapement, even with smaller screen, one bank of incubators should be used per individual lot of pikeminnow to avoid mixing lots. Vertical incubators are recommended for handling large lots because they are more efficient in water usage, space, and chemical treatments needed for fungus control than hatching in trays in a trough. Egg Trays and HatchinglRearing Containers Due to the need to keep many small lots isolated from each other, the FRH designed egg trays that were placed inside individual hatching/rearing containers. To ensure even more isolation, each. individual hatching/rearing container was put into an individual trough. The egg trays were round clear plexiglass rings (2 inches deep x 6.5-inch diameter x 0.25-inch thick) with plastic screening material (16 squares/inch). and support structures glued to the bottom. Screen size (16 squares/inch) was small enough to hold eggs off the bottom but large enough to allow fry to fall through upon hatching. Hatching/rearing containers were made by cutting the bottoms off white plastic buckets. Each was approximately 5 inches deep and 9 inches in diameter at the top (7.5 inches diameter at the bottom). For water circulation, two rectangular (3 x 5 inch) windows were cut out of the side of the 7