– How do scientists know that a sea creature is extinct or endangered if they haven’t explored 80% of the sea?

Question

– How do scientists know that a sea creature is extinct or endangered if they haven’t explored 80% of the sea?

In: 2

Answer 1

That “we haven’t explored 80%” is very misleading. We haven’t visited 80%, but we have scanned loads of it.

And we can never be sure if an animal is really extinct. That’s an estimation we make based on how often we see something. I.E. the last 30 years we saw 100 spiral headed snails per survey on average, this year we saw only 1 per survey, so it’s very likely that the species isn’t doing well.