A renowned British crocodile expert has admitted to 60 charges relating to bestiality and child abuse material.
An Australian court heard Adam Britton filmed himself torturing dozens of dogs until almost all died.
He would then post videos of the incidents online, where he also accessed child abuse material.
A leading zoologist who has worked on BBC and National Geographic productions, Britton will be sentenced at a later date.
At a hearing in the Northern Territory (NT) Supreme Court on Monday, prosecutors laid out the case against him.
Much of the details of Britton's crimes are too graphic to publish, and so "grotesque" the judge warned people to leave the courtroom.
Chief Justice Michael Grant said he was concerned hearing the facts of the case could cause "nervous shock", before taking the rare step of excusing security officers and junior court officials, local media reported.
Britton had a "sadistic sexual interest" in animals since at least 2014, prosecutors told the court, and along with exploiting his own pets, he had manipulated other dog owners into giving him theirs.
He would use the online marketplace platform Gumtree Australia to find people who were often reluctantly giving their pets away due to travel or work commitments, building a "rapport" with them to negotiate taking custody of the animals. If they reached out to Britton for updates on their old pets, he would tell them "false narratives" and send them old photos.
In reality, he was abusing the animals in a shipping container on his property that had been fitted out with recording equipment – which the court heard he called a "torture room" – before sharing footage of his crimes online under pseudonyms.
Such a video was eventually passed on to NT police who arrested Britton in April 2022.
Of the 42 dogs he abused in the 18 months leading up to his arrest, 39 died.
Britton has been remanded in custody since his arrest and will return to court for a sentencing hearing in December.
Born in West Yorkshire, Britton grew up in the UK before moving to Australia over 20 years ago to work with crocodiles.
With a PhD in zoology, the 51-year-old had built a global reputation for his expertise, holding an academic position at Charles Darwin University, and even hosting David Attenborough while the veteran broadcaster filmed part of the Life in Cold Blood docuseries on his property.
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