Tilikum the orca hit the headlines in February after killing whale trainer Dawn Brancheau, 40, during a show at the city's SeaWorld complex.
Celebrities including Matt Damon and Lee's ex-wife Pamela Anderson spoke out after the tragedy, urging the venues to be shut down and the killer whales released from the tourist attractions.
Animal-loving Lee has given his backing to the ongoing campaign, teaming up with officials from the People for the Ethical Treatment of Animals (PETA) to condemn the odd way park keepers reportedly extract semen from the whales to keep their breeding program up and running.
In the letter to Terry W. Prather, the President of SeaWorld, Lee brands the alleged practice "sick and twisted", writing, "After learning about the bizarre way you breed killer whales, my friends at PETA and I are stumped about SeaWorld's announcement that no people will ever again have direct contact with Tilikum, the orca who has killed three people including his trainer this year.
"We understand that you refuse to release this frustrated whale because he is your chief sperm bank, and we know from SeaWorld's own director of safety... that the way you get his sperm is by having someone get into the pool and masturbate him with a cow's vagina filled with hot water.
"Even during my wildest days with Motley Crue, I never could've imagined something so sick and twisted... I hope it doesn't take another tragic death for SeaWorld to realise it shouldn't frustrate these smart animals by keeping them in tanks."
Rachael Patan
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