Wild axolotls revert to default pink colour on picking up and placing

On picking up a wild axolotl with a water bucket then placing them down, they lose their original colour.

What I expected to happen was...:
On placing the freshly caught axolotl, I expected it to still be white, or brown, or whatever colour the wild axolotl was before picking it up.

What actually happened was...:
Instead when placing it, they were the default pink colour, and were no longer the white or brown colour they were before they were picked up.

Steps to Reproduce:
1. Find/spawn a wild axolotl in any colour except for default pink.
2. In survival mode, pick the wild axolotl up in a water bucket.
3. In survival mode, place the water bucket down on either land or water and note the new colour of the axolotl.