Please change the taming chart.

In current version of ARK, taming bloodstalker split into three part:

First, you get caught and bitten by the bloodstalker you want to tame.

You then break loose and start feeding it creatures(both tamed and wild would work) to bump up the taming effectiveness.

Finally after bumping up the taming effectiveness to 100%, you then get caught by it again and finish the taming process.

If you doing it right, you will always get bloodstalker with 100% bonus level(Ex: lv150→lv225)