im not sure why snakes do that. kind of like us people with eyes bigger than our stomachs. some of mine will make the "kill" but then never eat. what has worked for me a few times in the past is when the snake has the prey in its mouth i will grab the rat or mouse by the tail with the hemostats and wiggle it. most of the time this will cause the snake to constrict further and cause the snake to believe that he has actually killed some thing. that may sound strange but im sure that at least one person in here has received that look from a snake (the "hey, this thing is already dead" look). this actually happened with my rtb last night. she had the rat in her mouth for an hour just laying there with it. finally i wiggled the rat around, the boa constricted on it real tight, and about 20 minutes later she had it eaten. im not sure why it worked, but who cares? im just glad she ate.
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1.1.0 Colombian Redtail Boas (normals)
2.1.0 Sumatran Blood Pythons (normals)
1.0 Dumeril's Boa (normal)
0.1 Coastal Carpet Python (normal)
0.1 Jungle Carpet Python (normal)
1.1 Surinam Redtail Boa (normal)
0.1 Roommate (sigh...okay, she has a corn snake)