Peru agency says cause of dolphin deaths unsolved

LIMA, PERU (AP) - Peru’s Sea Institute says in its final report on the mass die-off earlier this year of nearly 900 dolphins and porpoises that the cause remains unknown.

The report released Tuesday rules out viral and bacterial infections and speculates that biotoxins or an unknown emerging disease could be to blame. It says testing ruled out morbillivirus, a type of distemper that some government officials had suggested as a likely cause.

The institute says experts could not determine whether any of the deaths were a direct effect of seismic soundings in undersea oil exploration carried out in the area. The environmental group Orca has insisted the seismic work was the likely cause.

Some leading scientists say the Sea Institute was late in gathering samples, hurting chances of determining the cause of death.

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