Fatherhood has made Prince William more determined to "stand up for what is very vulnerable and needs protecting".
The 31-year-old spoke of his affinity with wildlife during an informal chat filmed at Kensington Palace, which will be shown on ITV and CNN on Sunday and Monday respectively.
– Prince William
The wildlife is incredibly vulnerable and I feel a real protective instinct, more so now that I am a father, which is why I get emotional about it... you want to stand up for what is very vulnerable and needs protecting.
Elephants, rhinos and many other animals that are persecuted don't have a voice...
It's just so powerful. You'd think something that big and that's been around so long, would have worked out a way to avoid being caught and persecuted, but they really don't. I do feel anger, but I also feel really great hope that we will overcome this as a human race.