With a population bottleneck of only 21 individuals, it sounds like their entire population is inbred. Even if it's hundreds of individuals now.
Seems you need more like thousands to ensure survivability, and it gets non-linearly worse as population gets smaller.
https://www.sciencedirect.com/science/article/abs/pii/S00063...
Same thing happened to Cheetahs and, to a greater extent, Florida panthers.
Seems you need more like thousands to ensure survivability, and it gets non-linearly worse as population gets smaller.
https://www.sciencedirect.com/science/article/abs/pii/S00063...