Very easy to tame if you know what your doing. First tame an Ichthyosaur. Then grab a crossbow and some tranq arrows and find one and knock it out. It is not be able to attack if you are on the Ichthy. As you are taming it, be sure to remain on the Ichthy unless feeding narcs, so other creature don’t hurt you.

They are a really easy tame if near the barrier.

Just get a scuba suit and flippers and clear out the area.

Next just shoot it when facing thing the barrier and it will run into it getting stuck.

If it tries to attack you just move to the side they have a very large turning radius

Grab extra arrows/bullets to tame these (more than how much dododex shows), because you might need to catch breath and it will take time and might drop its torpor.

These are one of the few dinos that take less damage/topour from head shots. Aim for the body.

When it says 1.7% chance of death. It means it's going to die.

Taming a dunklosteous is not too hard if you do this.

1. Get lazurous chowder or scuba gear

2. Have kibble or prime meat ready

3. Have at least 2 good crossbows. Kill some alpha raptors to get some.

4. Use a mount. I recommend a Sarcosichus or a Baryonyx. Make sure you can fire off of its back.

5. Find one. They typically spawn near the edge of the map on The Island.

6. Clear out any hostile creatures that are too close. They will interfere with your tame.

7. Shoot it full of tranqs. This may take a while. They are slow, so simply kite them while riding your mount.

8. Once they are knocked out, put kibble and/or prime meat in their inventory. They may need narcotics depending on the level. Make sure to protect them.

9. You now have a Dunklosteous! I suggest bringing a cryopod because they are very slow swimmers.

Hope this helps, good luck! :)

Bring more tranq arrows then you think! Mine took 100 at close range, on the body, at LEVEL 3.

I took cooked prime meat (stays better longer) and got mine in only four feedings. On an icthy they don’t chase (mobile player here) happy taming- Survivor Belle

For Fjordur: actually very common spawns, but only at the bottom of sea trenches. When prepping to tame, be sure to clear out any sea scorpions or Megs nearby, or you'll be making drunk fish food.

X-Dunkys took me a lot more tranq arrows than Dododex would suggest, especially considering my 745% crossbow - that still took around 30 shots. Body shots are ideal, since the head is heavily armored.

Be careful starve taming! They don't wake up fast, but they eat very slowly, and mine wouldn't eat the last kibble piece when I dropped in all the ones dododexs calculator said. Let it starve an extra hundred or so food to avoid that happening to you!

They take roughly a fourth of the time it says to knock one with a tuso, the torpor from grabbing a dunkleo ignores it’s armor