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Name: Jason S Kay
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Dear Mr. or Ms. Scientist, why do fish come to the surface and gulp like they're breathing air or trying to eat when there's no food there?

I'm not sure of the correct answer but I can make some guesses. First, are you sure there is no food? Second, fish are able to suspend themselves in water by adjusting their buoyancy with an air bladder. This is an organ that like a balloon, is filled with air. Some fish that are deep living (e.g. lake trout) are rumored to stop fighting when caught as they are brought near the surface because the decrease in water pressure allows the air bladder to expand enough to shock the fish. Third, could it be that the fish you were observing has an adaptation to allow it to absorb oxygen from its stomach when there is not enough oxygen in the water for the gills to extract?? If this is a pet, try oxygenating the water and see if the behavior subsides. GOOD LUCK!

Michael B Lomonaco

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