I have a large juvenile box turtle that is 5.25 inches SCL and 405 grams in weight. He is very active with a very good appetite. But he sometimes makes whistling sounds when he breathes. There are no other symptoms of anything else. I have noticed the whistling sound for maybe the past 3 months. Initially I was very concerned and upped the temps a little and gave a little cod live oil for a few weeks. The whistling never really stopped. It does not happen when he is bedded down in his moss with his head poking out. It does not happen when he is basking. It happens when he is out and about, roaming his enclosure maybe looking for food. Or looking up at me begging for food...lol. No other symptoms have ever surfaced. No eye problems, no bubbles at the nose, no loss of appetite....nothing. What do you make of this?