You can tell this to hen and pigs. You will be astonished by their answers about how few generations of artificial selection will result in successful variety. 
I once spent a year working with a private zoo owner and collector. He had several species successfully bred in captivity, while the mainstream opinion was &quot;its impossible to breed Eublepharis turcmenicus in captivity&quot;. Before 1988 there were only 40 known specimen. He alone had 20 alive and breeding. Just a matter of observation, careful experiment and some money, not much. 
That hornbill is a challenge, but not impossible one. I bet you, its cheaper to establish breeding program, than spent money on poachers.<p>Disclaimer: Worked 6 years in nature conservation programmes.