Carrion would not speculate about motives or suspects, saying only that the local prosecutor was conducting the investigation.
Phone calls to the mayor's office and local jail went unanswered.
The grisly discovery has prompted calls for stricter controls on the island chain's human population, and especially the booming tourism business that some conservationists say is a major threat.
"The biggest problem we have in the Galápagos is excessive tourism," said Xavier Leon Vega, a spokesperson for Acción Ecológica, a group of ecologists based in Ecuador.
"The most fundamental change we need is to limit the number of tourist visitors to the area. We are putting too much pressure on the zone, and there should be stricter regulations."
Some Ecuadorian lawmakers are pushing a bill to curb immigration to the islands, he said.
Scott Henderson is the regional coordinator of marine conservation for the nonprofit Conservation International.
He cited historical mistrust between international conservation groups and some locals who came as "economic immigrants" and now scratch out meager livings in enterprises such as small-scale fishing operations.
(Read related story: "Illegal Fishing Threatens Galápagos Islands Waters" [March 12, 2004].)
Henderson would not speculate about the killings, but he said they had no specific precedent.
"There is precedent for killings done for penises and instances where industrial fishermen were blamed by locals for clubbing sea lions that robbed their large nets and lines," he said.
"But there has never been a whole community [of sea lions] clubbed to death on an uninhabited island," he said.
In 2001 at least 35 sea lions were found clubbed and mutilated on San Cristobal Island.
There have also been cases of protected wildlife being killed for local consumption.
Henderson, who has lived in the Galápagos for 15 years, said conservation groups and locals must look to deepen their dialogue with one another.
"Regardless of who is responsible for this act, it is important that the local community, including conservationists and fishermen and the broader community, work to protect natural resources that are the shared basis of all of our livelihoods."
"This is not about pointing fingers, but about working together for the future."
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