The article avoids the plural in the lead, which reads a little awkwardly.
For the record: octopuses is standard English, octopodes is the Greek-derived form and is vanishingly rare, and octopi treats a Greek word as though it were Latin. I suggest we just use octopuses throughout and not make a fuss about it in the article itself.
Agreed. I've changed the one occurrence in the Behaviour section.
octopodes is correct though
It's defensible, but it isn't what people write. Encyclopedias follow usage rather than leading it.