According to a report from MSNBC, Dr. Michael Domeier has voluntarily stopped the use of the Smart Position or Temperature Transmitting (SPOT) tags seen in National Geographic’s “Shark Men.” Domeier is quoted as saying that he has “stopped using such tags because of issues related to fin damage.”

Domeier went on to explain that the plastic bolts used in the tagging practice seen on “Shark Men” can result in deformation of the tagged shark’s dorsal fin, due to the fact that the plastic bolts are relatively permanent and do not degrade. The use of metal bolts that eventually rust away was not reasonable option, according to Domeier, because the bolts can rust unevenly and cause severe damage to the affected shark’s dorsal fin.

Domeier is working on a plan to resolve the issues with the SPOT tagging procedures, but the resolution is taking longer than expected, according to the MSNBC report. The article added that Domeier has turned down the opportunity to join the next season of “Shark Men” due to his work on developing this improved tagging technology and a current book project.