I won't define what I mean, but do it by example: There are perhaps 400 mountain gorillas, a distinct species, on Earth, and they all live in the same small area. The question is; given a chance to save the lives of an equal number of randomly chosen humans or all the gorillas, which do you save? Personally, I vote for the gorillas, partly because the chance of any of the humans being someone I know is vanishingly small.
This is a non-question. I am, admittedly an ecocentrist. I think we have direct moral duties to nature as a whole just like we do to people, and I think this is silly. Partially because I dont think moral systems should be tested by the crazy "out of nowhere scenarios that philosophers like to cook up" Testing of ethical systems should be done with things that could actually occur, with hypothetical scenarios used as a control.
(I think this because ethical systems are designed around what is actually true, the conclusions depend on the truth of the premises. It is like testing Utilitarianism, by arbitarily deciding that punishing an innocent person for murder will increase utility and pointing out how unjust that is even though this would never actually happen... it is ridiculous. For any ethical system one can think of a scenario where it produces an undesireable outcome.)
The real question is whether or not one would restrict the growth of a jungle villiage of 400 to save those gorillas. I would answer yes.
The same applies to quite a lot of critically endangered species, by the way. A more general point is; the reason that so many species are endangered is simply that there are too many people and we use too much of the ecosystem's resources. Assuming that you agree with that proposition, what are the acceptable ways of reducing our footprint and hence saving some or all of those species?
A lot of it is to stop being idiots. Example: when we build a new housing development, have a sustainable water supply and use natural landscaping so that the ecosystem can at least be partially extended into residential areas "let your yard grow wild" as it were. I live in AZ and people here insist on having grassy green lawns that are not only devoid of life, but also suck down water like french collaborators sucked nazi cock in WW2. STOP IT. We live in a fucking desert, not enough water for that. Here, have some creosote and a cactus garden, oh and a big rock too. I know, your yard isnt as much fun to roll around in with the kids especially with the harvester ants that now live there. Suck it up. Look, you have a beautiful chuckwalla sunning himself on that rock, and when else do you get to see a gila monster scarfing down baby rabbits? It's nice. I know I know, there is a rattlesnake in your yard, Comes with the lot. She was there before you were, she has kids too. Speaking of which you may want to watch where you put your hands in the toolshed. Zip it! You have been living there for over a year and that is the first time you have seen that snake, and you probably wont see her again for another 2.
Stopping organic farming and fully adopting GE crops is another way. Organic farming uses up more space and water to get the same crop yield. GE crops make this better AND your pesticides are now target specific. Trust me, it's kinda hard for an insect to evolve resistence to its own ecdysone bwahahaha!!!
And this brings me to ranchers. Stop opposing the reintroduction of wolves. I know they kill your cattle. I dont care. It isnt as if you are grazing your cattle on your own heavily fertilized field. You are over-grazing your thousands and thousands of cows on public trust land. That land is not a pasture. It is actual nature. The wolves evolved there, they have more a right to be there than your fucking cows. Maybe you can selectively breed your cows so they defend themselves from wolves. Suck it up. It isnt as if they will kill all your cows. They may take 1 or 2 a month if you hire someone to watch the herd, so what if those two are gay? You have thousands and they breed. Hell, it isnt as if you actually invest a whole lot of money while you overgraze public trust land. You pay a pittance to lease it over the summer months. You get what you pay for.
As for animal testing... from an evolutionary point of view, those animal test subjects are amazingly successful. We are their only nature predator we must keep their populations in check!
In all seriousness, we have no moral duties to them not to experiment on them because they are not a part of an evolved system independent of their being lab animals. If anything, we have a moral duty to keep experimenting on them because that is the niche they fill in their environment. I am still working on this bizzar ethical system of mine in which we have moral duties to evolved systems instead of individuals directly, and so far I really like the results.