Hi-
As long as his abdomen is rounded and not shrinking excessively, your tarantula is doing fine in its own mysterious way. These types of tarantulas are very mysterious and, as I've read, many spider experts like to call them "oddballs" that put their owners into unnecessary fear about their health. Sometimes they stop eating for long periods of time, and then start eating again many months later. These behaviors are reported frequently. He could be perfectly healthy. Though stopping to eat usually signifies an upcoming molt, there are frequent times they dont: Sometimes they don't molt for as long as three years, though this is usually recorded in the females. (This doesn't happen in the wild- only in 'captivity').
Keep a good eye on him and if his abdomen does not seem to be 'disappearing' before your eyes, I would not worry.
Occassionally, you can try the following:they will eat crickets, moths, beetle larvae (meal worms or superworms), houseflies and cockroaches. But don't try to force it. A good rule of thumb is to offer prey items that are about half the spider's size, although some tarantulas are aggressive eaters and will eat prey as large as themselves. Spiders, in general, will keep eating until they are full, approaching a molt, or ready to lay an egg sac. Care must be taken to remove any prey items that have not been eaten within 24 hours or so, as uneaten prey items can be stressful for the tarantula and have been known to damage them if left longer.
So basically, not eating for 2 weeks can signify either a molt is approaching or that you just have a typical oddball tarantula. They go onto their backs during a molt, so dont worry if this should occur. If he does not molt, just keep your eye on him, and if his belly is not 'melting away' on him, consider it normal behavior. I do hope i could help and shed light on this for you.
Good luck.
-christine
Christine M. Peterson, Licensed Veterinary Technician (NY)
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