Seriously broken. Don't use! Or use with extreme caution and only use the Hunt and Retrieve! They ignore your commands, do whatever they please and more often than not just fly off aggroing everything. This piece of a shit seeks to destroy you, wild or tamed.
"No hunt" means this bird goes on Aggressive when you whistle anything for any other dino - EVEN IF it's on passive AND ignore group whistles. An Ichtyornis on passive and any of the Hunt settings might suddenly go on neutral just because. "Hunt" causes it to go attack any dodo or fish it can find - so they usually get lost flying too far or they aggro something stupid.
The last Ichtyornis I had attacked a bronto right next to my newbie base and got almost all of my tames killed and half of my base destroyed. I've seen them attack turtles, paras and moschops, too, not accidentally. So I wouldn't be surprised if they actually would attack brontos just for the fun of it.
I had the pleasure of befriending one of these animals. Despite popular opinion, I find ichthyornis birds to be quite charming and graceful. So much that I found myself taming one. After he woke up, I saw a fire in Greg. From then on, we would be best friends. He’d come with me everywhere. From simple resource gathering to Bronto taming, Greg would be there supporting me from my shoulder. When I was too tired to go fishing or hunting, Greg was there to do it for me. He even makes the effort to make sure I get the best meat out of it. He is a quick learner, he went from from level 20 to level 40 in a day. Anywhere I go, he comes. Anything I need, he makes it his top priority. To this day, Greg continues to be my best friend and sometimes we just hang out on the beach or go fishing even when the resources aren’t needed. I thank Greg for his time with me and his endless favors that he has completed for me. Thank you, Greg.
Just tamed one of these myself, after reading the story of Greg I decided there was only one name suitable for this creature. I love My Greg so much, he is amazing. Shortly after I tamed him I was out gathering with him perched on my shoulder when I was attacked by a group of compys, Greg instantly Launched himself off my shoulder and flew into the air with on in his Jaws while my raptor killed the other 2. I've never enjoyed watching something that has attacked me die so much.... Until a couple minutes later. A Dilo ran up and before it could even blind me Greg swooped in and grabbed him up in his Jaws flew into the air and tore him to shreds. 10/10 would tame a whole battalion of Greg's.
Also they are great for catching fish and taming otters.