In everything other than genes, Johnson is a perfect bull for Columbus, but we know the consequences of allowing a singular bull to breed in excess.
Popular sire effect (AKA: Popular stud syndrome)
is a prevalent problem facing the dog world right now, some breeds are so inbred that there's little hope of them continuing to be viable without bringing new genetics. Which, barring notable few breeds, is viewed as blasphemy to merely
suggest.
The zoo world would do well to avoid that situation at all costs.
Especially when there are several other bulls in the country sitting completely underutilized.
And how many of those bulls are proven natural breeders like Johnson is?
North America suffers from a shortage of bull elephants
who know how to breed.
Even considering the worry of popular sire effect, I can't say that I blame Columbus for jumping at the chance to import Johnson from Canada. There's no doubting his skill with the ladies! Lol.
A proven breeder is a sure thing (On the bull end of things anyway), so why take the risk on a more genetically valuable, but unproven bull? Columbus' cows need to get pregnant
right now in order to salvage potential breeding careers for them. Columbus can ill-afford to bring in a youngster and just cross their fingers and
hope that he'll know what he's doing.
Of course we can't know all the details, but I just worry Columbus is making a move that may come back to bite them down the line. Getting calves on the ground is the priority, but where will we be in a few decades when half the animals in NA are related to each other?
If the situation ever degrades to that state, I suppose we'll have to take a page out of the dog breeders' book and measure the COI (Coefficient of inbreeding) between individual pairings, ultimately aiming to produce calves that have the lowest COI possible as available within the population.