There isn’t yet reason to believe that overall animal populations are decreasing.
WWF claims that “on average, we’ve seen an astonishing 60% decline in the size of populations of mammals, birds, fish, reptiles, and amphibians in just over 40 years.” I don’t know how they arrived at this estimate though.
Yeah, that’s interesting. Clearly there is major decline in some populations right now, especially large vertebrates and birds. I guess the relevant questions are: will those last a long time (at least a few hundred years), and: is there complementary growth in other populations (invertebrates)? Especially if species that are succeeding are smaller on average than the ones declining, as you might expect there to be even more animals then. Cephalopod populations, for example, have increased since the 50s: https://www.cell.com/current-biology/fulltext/S0960-9822(16)30319-0
WWF claims that “on average, we’ve seen an astonishing 60% decline in the size of populations of mammals, birds, fish, reptiles, and amphibians in just over 40 years.” I don’t know how they arrived at this estimate though.
Thanks for linking!
Yeah, that’s interesting. Clearly there is major decline in some populations right now, especially large vertebrates and birds. I guess the relevant questions are: will those last a long time (at least a few hundred years), and: is there complementary growth in other populations (invertebrates)? Especially if species that are succeeding are smaller on average than the ones declining, as you might expect there to be even more animals then. Cephalopod populations, for example, have increased since the 50s: https://www.cell.com/current-biology/fulltext/S0960-9822(16)30319-0