Figure 112. Plastic bag shipment of fish. The container should be at least 4-mil 

 plastic and preferably thicker for catfish and large sunfish. (l) The proper weight 

 of fish is combined with the required amount of water. (2) Fish then are poured 

 into the plastic shipping bag. Any chemicals such as anesthetics or buffers 

 should be added to the water before the fish are introduced. (3) The bag is then 

 filled with oxygen. All the air is first forced out of the bag, which is then refilled 

 with oxygen through a small hole at the top of the bag, or the bag can be 

 bunched tightly around the oxygen hose. Approximately 75"i> of the volume of 

 the bag should be oxygen. The bag then is heat-sealed or the top is twisted 

 tightly and secured with a heavy-duty rubber band. (4) Because cool water can 

 support more fish than warm water, the water temperature in the shipping con- 

 tainer should be kept as cool as the fish will tolerate. If ice is needed it may be 

 placed directly with the fish or in separate bags (arrow) next to the fish con- 

 tainer. In this way the fish and water are cooled simultaneously. (5) 

 Polyurethane foam - inch thick is excellent insulation for shipping, but it is 

 heavier and less efficient than foam. (6) The package then is sealed and prop- 

 erly labelled for shipment. (Photos courtesy Don Toney, Willow Beach National 

 Fish Hatchery, FWS.) 



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