This is a good question. I’m not aware of any EA-related investigations of this area.
Generally, when I’ve read articles and papers on this topic (which have ranged from “very alarmed” to “mildly concerned, but pushing back on alarm”), I’ve had a hard time figuring out where humans come in.
I worry about climate change and crop disease and soil degredation and other things that could damage our food supply, but the extinction of not-very-populous species, or the deterioration of a forest where no food is grown and few people visit, seems… bad, but not nearly as directly threatening as the issues EA usually thinks about. And it’s hard to imagine ecosystem shifts making the lives of wild animals too much worse than they already are.
Did the report you’ve linked have any particular theories about the ways in which these changes will affect humans? Which parts of our civilization are at risk?
Yes, we may be losing things that are precious and beautiful, and robbing our children of their natural heritage, but are people going to starve or get sick or otherwise suffer harms deeper than disappointment and wistful regret? Those are bad, but many other things seem to be equally disappointing and regrettable to people; the environment (save for climate change X-risk) seems not to have been especially “sticky” as a thing people care about.
(I’m not trying to argue against the importance of biodiversity/ecosystem health; I’m just genuinely uncertain about the main risk/source of negative impact.)
I have wondered if species extinction should be treated as worse than simply the welfare/suffering of the last members of a species.
For example, I take it that most EAs would view the loss of the last 100 million humans as much worse than the 7.6 billion who might die before them in an existential catastrophe, particularly if the survivors still had a chance at re-building human civilizations. Likewise, if we lose a species, we lose any future value that was intrinsic to having that species in existence. And as most human value is likely to be in the far future this could also be true for animals, but this can only be realized if the species remains extant (i.e. future humans may wish to create zoo simulations or worlds after WBE or space colonization).
While I agree that a lot of both near- and long-term human related causes seem more important than protecting breeding populations of all endangered species, it could be that we are undervaluing the intrinsic benefit of biodiversity. A cheap way of safeguarding against the case we are currently under prioritizing species preservation would just be to take some genetic samples from those that are endangered (already being done). Then the opportunity exists to recreate extant species in the future if resources are available and we decide they should have been conserved.