I highly recommend counting on being dragged off by one of these guys, stay away from the water even on a tall mount, the lower you go, the higher the chances of you being knocked off your mount and dragged off into the water. Have a sword or bolas, I usually go with the sword option as you can just go on to kill it immediately.
The higher your Melee the better your chances of killing them with little damage taken. I've fought them off easier with the sword.
Avoid Dinos that are low to the ground cause they will snatch right off... Just avoid the swamps until you have the appropriate equipment and armor to deal with Dinos in the swamp. These guys are worse than Sarcos.
For all the noobs out there, if these things kidnap you in the swamp, here’s what to do. Take out your bow/ gun. Pray you have ammo and fire right into its head. This strategy has saved me countless times.
P.S. If you have a strong melee weapon such as a pike or sword on you, that also works.