Transcript for Yellowstone National Park Tourists Speak Out About Baby Bison

difficult time. An ABC exclusive. The yellowstone national park tour IST who put that baby bison in their trunk that led him to being euthanized. After facing fines of outrage on social media, linsey Davis sat down with them both. This morning the father and son at the center of that baby bison controversy are telling their side of the story answering the question why did they put a newborn bison in the back of their SUV and also share how they would handle the situation now if they got a chance to do it all over again. This morning, for the first time, the yellowstone national park tourist who sparked a global firestorm are now setting the record straight. Do you think that people were unfairly critical and way too harsh? I think so. I think people didn't know the whole story. Reporter: Shamash Kassam and his son shaquille were the subject of scathing headlines after putting this baby bison in the back of their SUV, an act park rangers caused the baby to be rejected by its herd and ultimately euthanized. I was so shocked. It was the way it was presented. It was like we didn't know what we were doing. We picked up the bison because it was shivering. That was not the reason why we picked up the bison because it was abandoned by the herd. We thought we were doing a nice thing by taking it to the rangers. Reporter: This video taken by a different visitor shows the same little calf earlier struggling to make it across the river and keep up with the others. You can see it here appearing in distress and trembling. It was totally huddled next to the engine of the other car and we decided we would leave it alone and go. Reporter: But about a half mile down the road his dad had a change of heart. I told him let's go see what is happening because that thing is going to be eaten alive. Reporter: Shamash Kassam and his son regularly take trips centered around wildlife. Polar bear, tigers, elephants and bears. I am a farmer from Africa and many times it has happened that the poachers kill the mother and we pick up the phone and give it to the rangers and they look after it. Reporter: With no cell service to call a park ranger and with the herd long gone, they loaded the newborn into the SUV and took it to the park ranger. Did you have any reservations about that? Did you think maybe this isn't a good idea? The hair was standing a little bit on that one. I wasn't 100% sure but when I saw the calf outside shaking I felt that, you know, this was the right thing to do. Reporter: They say they never imagined how fiercely critics would pounce. Online this petition justice for baby bison requesting harsh punishments to tourists who looted a bison calf into their vehicle and were ultimately responsible for its death. I'm asking you to speculate here, but do you think there was any way that that baby bison would have survived along the side of the road? No way, 100%. No way. It would have been either killed by a car or something or worse. Eaten alive. Baby, get your strength. Reporter: You wanted to help. That's the point. If you had to do it all over again, how would you react now? In yellowstone park we would just leave it because they say let the nature take the course. Reporter: Yesterday shamash Kassam went to court ordered to pay a $230 citation and make a $500 doughtation no yellowstone and the park has gotten backlash for euthanizing the baby bison but park officials say they don't have the ability to care for it. You get to hear their side of the story. Regardless of what -- if you agree, they're really not the clueless tourists that initially many of the stories painted them out to -- So hard to disagree with their motivation. Being with them it was clear they had no intention of doing they harm. They did want to help. Linsey, thanks so much for bringing that to us.

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