San Diego

About 25 sea lions in the Galapagos National Park were butchered for their sexual organs earlier this month, angering biologists who work to conserve them.

Mutilated: these sea lions were killed for their sex organs, which could end up on sale in Asia. Credit: CDRS/GNPS

The mutilated sea lions of both sexes were found on the morning of 14 July on a beach on San Cristobal Island in an area near the airport where tourists go to view the island's diverse animal life. The sea lions had been clubbed in the head the night before, and their penises, gonads or ovaries cut out. Some of the animals were still alive when they were found.

Michael Bliemsrieder, a US-based biologist with the Charles Darwin Foundation, says sea-lion sex organs are sold in Asia for medicinal purposes.

This year's sea-cucumber harvest is under way in the islands' waters, attracting many foreign traders. Bliemsrieder says Ecuadorian authorities are investigating whether any of the traders were involved in the attack. There have been isolated attacks on sea lions during previous harvests, officials say, but nothing on this scale.

Paola Diaz, a spokeswoman for the Charles Darwin Research Station on the islands, says scientists and the community have raised around US$5,000 for a reward for information leading to an arrest.