He explains: "If you introduce these guys back into the wild they've got to go through exactly the same trip they've just been through to get into this country and the amount of stress they go through is a lot."
Centres like the Living Rainforest try and raise awareness that some animals shouldn't be kept as pets.
Mike Bungard hopes to help stop the trade in rare reptiles and insects.
He explains: "If we educate people about why you don't want to keep them as pets then hopefully we'll stop people wanting to keep them then the illegal trade in them will slow down."
But for now it's business as usual for the men at Heathrow - and back to the crates.