The question arises now what is killing the octopus of Vila Nova de Gaia? This question has obsessed the Portuguese city. Douro River from Porto, since Jan, Five hundred kg of dead octopus were found on a 1.8-mile (3 km) stretch of local beach. Director of the Gaia Biological Park Nuno Oliveria said it’s very strange that so many should be killed, a nature shelter on the outskirts of Vila Nova de Gaia.
There's nothing in the scientific literature for this kind of mass mortality among octopus. Especially when no one knows what killed them. Local biologists have ruled out pollution or contamination because no other species were affected.
Vila Nova de Gaia's municipal government had firefighters collect the dead animals; many will now be sent to Lisbon's veterinary lab for testing, a process expected to take up to two weeks. It is may be affected by a parasite, bacteria or a powerful virus. It has been affected octopus of all ages and sizes, says Mike Weber, director of the Aguda coastal station, an aquarium and biological research institute located in Gaia.
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