rat snake

Question
QUESTION: I raise bantum chickens, and a large black rat snake has regularly come to feed on my chicks and eggs. I have caught him in the act several times, and have hauled him off a couple of miles and released him, and he comes back. I know because he has a wound on his back from getting caught in plastic deer netting, that i had to cut him free from.  The last time I caught him, I kept him. which was 3 weeks ago. he was eating on of my duck eggs that was being "set on" my the mother duck. he went to a 55 aquarium with a lid, and he is on the covered porch of the house. He threw up the duck egg. stress i guess, though the capture was uneventful. this snake has never struck or been hostile, even took it patiently when I had to cut out the deer netting in several places on its body. I tried to feed him another egg, which sat for a week, with no interest.  Then I fed a mouse.  I think he ate that as I did not find any remains. that was 2 weeks ago. since then I have put a white mouse in there with no interest, i tried several times. then I bought a brown mouse, he eventually killed it, but didn't eat right away.  then he ate and threw it up the next day. ( yesterday). I am worried this snake is ill.  It is really hot here, and I have had a fan on the cage and even placed refreezable cold pack in the aquarium as i think it is too hot in there for him ( thermometer is at 85). Then i read your answer about stomach acid needing to "refresh".  Except this big guy should eat a couple of mice, if my boa experience translated at all.  He is about 5ft give or take a couple of inches.
Other than letting him go, any suggestions.  I will release him , as I would never take an animals life ONLY because I want to observe him; 'keep" him.  
I thought i strange he went after the duck egg, as they are quite a bite for the size of his head, it was stretched to the max, as I watched him eat it.  We are not certain this animal was not a pet at one time.  we found a small expemsive pet carrier down at our mailbox, with the door open. someone released something, something that they didn't want to wait to retrieve the carrier for.  This is the most docile wild snake I have ever encountered ( and have encountered hundreds), and no matter how far away i take him, ends up back here.  comments? ideas?
Thank

ANSWER: Sharon,
 That is a really good story. Most folks would have killed the snake a long time ago but I applaud your efforts. At his size, he can go 5 months without eating and be ok. If it was me, the next time I took a longer trip out of town, I would release him and try once more to set him free. He sounds like he is not adapting well to captivity. It is very odd that he is not aggressive. It also makes sense that he might of found a food supply and just wants to stay close to it. Here id a care sheet on rat snakes. Follow it and see if you can keep him. If not, sacrifice the gas to drive 30 miles away and release him. Hope this helps.

http://www.reptileallsorts.com/blkratcareguide.htm

---------- FOLLOW-UP ----------

QUESTION: Your advice about releasing him "far away" would be excellent advice for 99% of the people that have a similar problem, except I forgot to include one factor. I live in the ozarks, on a bluff overlooking a sizable river.  I am already at war with the genorous amount of copperheads, and the occasional water moccasin ( cottonmouth).  I have plenty of other snakes that are welcome if the can survive the geese, burros , goats, without getting trampled, not to mention the dozen or so neutered cats that live for free here.  I take those non-venomous that survive the gaunlet and get to the house or bird yards , to the wild back part of our acreage and free them.
I have never attempted to retain any of those, as a child I found that most snakes do NOT adapt, and live in fear and stress in captivity.
This one is so passive, it IS very strange, yet he looks very healthy and magnificent, except for the scar from the deer mesh/netting.
Only during the fisrt few minutes as he explored the tank, has he shown interest in the "exit".  I also forgot to clarify that the reason we keep catching him, is he comes in broad daylight, through all those cats, and the pair of great pyrenees that guard the flocks, and with us outisde, and acts as if he doesn't know any better, to have lunch. I have photos of him last year, crawling all over the pidgeon hutch, trying to find a way into the hutch for some squab .  and he and I have had a tug of war before, with me trying to evict him from inside of the banty house, when he was trying to stay. AND, earlier this year, i went out to check banty setting hens, and found him curled up in as nest box.  Lastyear when he got himself caught in the netting, we stood right there on the deck and said, "look what that idiot is doing "; again broad daylight.
This snake has very little wild , actually none, behavior.  It is a mystery to me .  the last time we took him a mile down our uninhabited road and turn ed him loose, I didn't want to get into the bushes myself, so I just placed him on the edge of the road, and expected an explosion of speed toward freedom. he did nothing, just laid there. so I go over and touch him, hoping the unexpected touch would force evasive action, nothing.  finally, I picked him back up and did place him in the bushes. Good Grief, we said . He may have decided since we have never harmed him, we are nothing to fear.  Thank you for your time.  I may try to wait for a full week, and introduce some food.
question:
would my odor on an egg make him reject the egg ( I KNOW he likes eggs)?
and , have you ever heard of snakes rejecting white mice?  ( as he had zero interest in the white mouse, and I had to watch that carefully so the mouse did not bite him)?
Could the heat make him throwup?
His tank is on a sitting encloded porch off my bedroom, there is no noise or traffic through there, very quiet (little vibrations); I placed it as stress free as possible.  he also has not minded or struggled ( though he does tense up) when i pick him up to chnage his substrate and clean his water bowl ( which he likes very much), so he is not "obviously" stressed.
thank you again

Answer
would my odor on an egg make him reject the egg ( I KNOW he likes eggs)? I don't think so. All of mine feed on thawed rats which I have handled and I imagine your scent is all over the general area. I would guess he is used to you by now.


and , have you ever heard of snakes rejecting white mice?  ( as he had zero interest in the white mouse, and I had to watch that carefully so the mouse did not bite him)? Yes. It is not uncommon for a snake to prefer one color or the other, although most will eat either. I have one python that would only eat hamsters until I successfully converted her over to rats.


Could the heat make him throwup? It could, although if he is out of direct sunlight, it shouldn't.


His tank is on a sitting encloded porch off my bedroom, there is no noise or traffic through there, very quiet (little vibrations); I placed it as stress free as possible.  he also has not minded or struggled ( though he does tense up) when i pick him up to chnage his substrate and clean his water bowl ( which he likes very much), so he is not "obviously" stressed.
thank you again

Not eating is also a sign of stress, but I would not be worried unless he does not eat for months. Worst case scenario, ship him to me and I can release him here in Tennessee. I rescue dozens of rat, corn, and banded water snakes from the local dog park each summer and release them around the house. There are about 100 acres here for them to play on.