They are notoriously difficult to feed as wc.
That said, I had a wc male that I found malingering away in a wholesalers that was covered in retained shed skin. I kept him in a warm, humid and very quiet viv, the retained skin came off within 24 hours and a mouse fluff that I left in the viv was eaten. He fed every time but only by leaving it in overnight.
So they will take defrost mice but I think I was just very lucky.
You may need to scent with lizard to get them feeding. Live feeding may also be an option.
However, the fact that they were feeding before you took them on suggests your husbandry isn't right, especially as they came from different places and were both feeding.
Tube feeding is not the answer.
I would suggest you contact both sellers and ask them EXACTLY how they were keeping them, what food was offered and how it was offered, down to the smallest detail of how they defrosted the food (assuming they ere fed frozen/thawed and what colour the fur was.
When I first got my Mexican hognoses, CB but imported from the US, the male just would not feed. Turned out that the dealer I got them from defrosted differently to me, adopted the same way and he fed straight away.
Other keepers have had snakes that would only eat mice with specific fur colour.
Pinks are sometimes useful to get snakes back into feeding.
But I think the key to this is an honest look at your husbandry compared to how they were kept when they were feeding.

 

I’ve also worried about my husbandry, but I’ve done research and tried making little tweaks. I found out the male lived in a rack, and I can bet the female did too. They’re in enclosures now and I wonder if that is stressing them out.

 

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they do better in tubs than caging, their exceptionally shy, they need a large shallow water dish (a quiche dish is good), they spend a lot of time in the water, like xenopeltis their skin will suffer if kept too dry. moss is a good substrate topper for them to stalk from. the room should be on the warm side or setup gently air-heated, without direct lighting, or dim led lighting at most (their one of those species arcadia don't believe exist). they often feed better when offered food while soaking. their parasite load should only be addressed once settled hydrated and feeding, unless they're actively passing them in their stools. they don't like handling and start stressing very quickly, for such a small snake their bite is surprising (like elapsoides). in the wild they can often be found a few inches off the ground on tiny branches waiting for something to strike at, they're not active hunters but rather ambush predators like gaboons bloods etc that's why they're so chubby, opportunities are few and far between, so feed accordingly, females just because of their size tend to be easier.

rgds
ed

They are in storage tubs but they’re larger ones. They both have large water dishes they occasionally soak in. They are kept quite humid. My room stay a bit warmer, especially during these summer months. These are LTC that have already been treated for parasites. My female had an infection which is why I originally took her to the vet. I only handle them when necessary, they’re both sweet snakes. They have many hiding places and lots of substrate to burrow in..
I’m looking at a small rack for them..I really don’t like racks long term but if that’s what they seem to prefer and they’ll eat I’m willing to try it.

 

Can you post some pictures of their enclosures. What is the heat source and how are you measuring and controlling the temperature?

 

Excuse the water dish, I haven’t changed it yet today. This was meant to be a temporary enclosure, I have PVC’s being made that were going to be bioactive for them..this is the males setup, it’s about 30x18”..he has a heat mat hooked up to a thermostat set to 88. I have a hygrometer in the back that stays about 80%

 

There's your problem.
You are using a heat mat.
These are tropical snakes that need a warm ambientvair temperature, which a mat cannot give.
Heat mats are a contact heater. They don't warm the air.
Great in a heated room to provide an elevated hot spot, or for species that don't need warm ambient air temperatures, but not for what you need.
I can guarantee that'll this is the issue.
You need to use an overhead heater that will warm the air, not the substrate they are laying on.

 

I don’t believe this is the problem. I had overhead heating for them before switching to heat mats and it made no difference. Even when snakes “bask”, they are lying there because the sun has already made the rock hot, providing heat to their belly. Also, my ambient room temp is 76 right now.

 

How are you trying to feed them?
Drop feeding or strike/ tease feeding?

I never really had any issues with WC adult Viper boas - I would tease feed them small prey items (fuzzy mice), their snappiness and strike response meant they usually struck and bit anything that touched them. It was then a case of doing this until they hold on to what they bite, and then staying really still until they decide to swallow it. Works best with relatively small prey items like fuzzy mice.

They seem to like wallowing in high humidity, on substrate that is moist/ damp to the point it might give other snakes skin blisters. They also don't seem to like too much heat. I had best success with ambient temperatures around 24c, no higher. They will avoid higher temps than this in my experience.

They also do not need feeding very often. They seem to be very energy efficient snakes. One small meal lasts them a good while, so I would feed them maybe once a month or so. Especially once they got the hang of feeding and would accept larger prey like adult mice. This also meant there was minimal stress between feedings - definitely a species you do not want to bother too often.

I used to keep mine in tubs when I had them, I would not now. As long as they have plenty of cover, and the right humidity and temperature, they should be fine. I would provide a little more low cover to your setup above, maybe more plastic plants or leaf litter they can hide under.

The babies on the other hand... those will make you tear your hair out...

 

I try tease feeding and after about 10 minutes of absolutely no interest I leave it there overnight and it never gets eaten. I’ve tried different prey sizes too. The enclosure is very humid. I notice the male laying just off to the side of the heat mat, and the female will lay directly on hers. I’ve been offering food every 2-3 weeks..the male hasn’t eaten since March. Female hasn’t eaten normal prey since February, but has been tube fed at the vet twice. I’ll add some more cover, maybe try a live plant in there. Your boas are beautiful! Love this species..hope to breed them eventually.

 

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i hate giving op's conflicting info when they're in need of help, but even more than that i dislike disagreeing with a keeper of Ian's skill and experience. but that's the nature of the forum i suppose.

so, as for heatmats being an outdated method i have to disagree, heat emitters for air heating considerably predate heatmats, so heatmats are technically the newer tech, though the bulbs have improved in production methods and efficiency, their still very much the same use case, though specialist ceramics are much better, (except arcadia heat emitters, their frankly very limited in their uses) we used to use ceramics meant for keeping food hot, yes I'm that old, in fact the first pet heatmats on the uk market weren't for reptiles, they were for aquariums believe it or not, i used the very 1st commercially available ones, again yes I'm that old. just because the sun is high above warming the air (and the soil) doesn't always translate to keeping a snake in a box, whether a cage or tub.

So aspera and heating and specifically in the U.S, aspera have been bred to at least F2 solely in racks with underbelly heating, inc at least f1 het albinos (so have indigo's cribo's < a travesty, mangroves, bloods, boas constrictors (to get a b.c.c to carry a litter to a successful term is a testament to a heatmat's suitability) many many many thousands of regius to god knows what generation, and virtually every species u can think of, whether racks are appropriate housing for that species or not.

In the U.S ambient's are typically higher, more uniform than in blighty, also energy is cheaper so heating the background temps of reptile rooms is far more viable than in the u.k. given the info supplied by the op re his setup/temps i do not believe the 76of room temp/heatmat is the cause of the non feeding.

some ideas, make sure the vipers have direct contact with heated bottom, sitting on 1.5" of substrate rapidly diffuses a 88of output if that makes sense (86-88 is preferable to 88-90), offer food less frequently, every 10 days, this is to reduce stress caused by failed attempts, only feed a couple hours after dark, ie midnight, offer young LIVE mice, LIVE lrg rat pups, avoid white lab strains and try to get natural colours, but if white is all u can get so be it, try putting the live food in a covered dish with a small access hole, it encourages a more instinctive hunt (this works with other small boas like eryx charina and rosys).

that little half round hide in the pic isn't suitable for aspera, instead a deep mix of leaves/chopped moss throughout the setup will allow them to move unseen wherever they wish, remove the corner plastic plants, the big leafy one is good, FLAT bark on top is helpful. spray the tub heavily with warm water 1 hour before feeding attempts (the rain brings all the animals out to play), black out the tub completely, tape paper around the entire circumference of the tub..

lastly, you have chosen a notoriously finicky species to acclimate from wc, ltc is only helpful if they've actually settled, otherwise there's not much improvement over wc. many wild aspera simply perish, there is a percentage that are naturally more suited to captivity, they stress less and are simply more accepting of lab rodents, that's why some thrive and others fail under identical conditions.

rgds
ed.

Unfortunately controversial info is an issue of the community..animals have been kept in different ways, both successfully. Both vipers have direct access to their heat mats..and they use them. The male likes to sit off to the side but I felt the bottom and its warm where he sits. The female will sit right in the middle. I offer food every 2 weeks. He has about 3+ inches of moss/leaf litter to move around in..only time I see him is occasionally in his water dish or a head poking out lol. I have yet to try live food as I’d prefer not to feed live, but my vet also mentioned that as an option to try so might have to give that a go. Thank you!!

 

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