The point is that birds, generally, whatever one's personal preferences are a visible indication of the the whole planet's health. The seabirds of the Northern Isles have been monitored for many years because of this. If entire populations of species, involing tens of thousands of seabirds fail to breed and this is proven- it is for the survival of you and I that should be the concern. We may not be able to detect the health of the marine system but the visibe effects on the scale that we are seeing now, should be alerting us to the fact that things are seriously wrong.