In response to your interest in the Fer-De Lance. Just a note as to the name Fer-De lance. It is not recognized as valid. Numerous Lanceheads may be generically referred to as a Fer-De lance. There is estimated 37 different types of Lanceheads (Bothrops) and about 1/3 of these are referred to as Fer-De Lance. There are several books available that have references to the Bothrops group. Campbell and Lamar have a new 2 volume set Venomous Reptiles of the Western Hemisphere, which contains a lot of info that might interest you. As far as the Bothrops group, which contains many large terrestrial pit vipers, most of which are capable of fatal bites. I have had experience of working with numerous Bothrops over the years. They are not only veritable in patterns and colors but temperament as well. I have worked with these animals in the field and maintained large numbers in captivity. As much as we would like to think they are predictable, they are not. Sub adults are more flighty than juveniles and mature adults, not say that juveniles and adults are not capable of spastic attitudes. They can be nervous and very quick.
Since the 1970's, I have focused most of my work on the island of St. Lucia in the West Indies with the St. Luican Lancehead. This is one of the largest Bothrops of the Fer-De Lance type. In the wild this snake is usually quiet docile and alert, unless touched by a hook. Keep in mind it is still capable of unpredictable temperament I had one that was about 5 1/2' feet in length, that darted out at a pace that would rival any Black Mamba.
As far as keeping venomous snakes in private collections, it is great that it is possible to do so, but common sense and safety is a must. For those who keep them just to impress others, don't. Those who have a serious interest, always use caution and do your research. The Fer-De Lance demands the utmost respect, so I would not recommend these to the novice collectors. More progressive work with snakes is done in the private sector than any zoo, museum or university. The private sector will be legislated quickly if we are not careful.
Good luck with your studies,
Chris, Bothrops Caribbaeus
Fer-De Lance type pit vipers are the ultimate predator.
If you have any questions, please post them.