The only problem I have with this funny comic is the poor comparison. Humans can actively plan, communicate, & alter our environment. Deer cannot. If their population booms (because we killed all their other predators... Oops) then we do need to fill in the gaps until conservation efforts can restore the other populations, such as wolves. That is our duty, to keep the ecosystem in balance. It's also respectful (In my opinion, at least) to the animals that we kill to at least let them serve a purpose, to feed & cloth us, to not waste their life.
Wait, so your saying humans actively plan and communicate about the impact we have on the environment? I mean in theory yes, but in reality, not really.
I didn't just mean regarding climate change specifically, but more broadly our ability to alter the world around us with technology & language. Take agriculture, as an example: We've domesticated countless crops to better suit our dietary needs, we can plan our crops to meet our populations' needs, even make population projections & plan our future farming accordingly. Not that we're always particularly good at it, we have plenty of issues not planning & coordinating enough, but we'd have starved ourselves of resources an awfully long time ago had it not been for our capacity for change. Deer can't do that. We can see that we've put their population in a position where they'd starve themselves without the predators, & the deer can't fix that themselves. They'll simply keep eating until there's no food left, & their population will collapse, alongside a large portion of the ecosystems they inhabit. It's our responsibility, now, to fix that. Both by filling the gaps of former predators by taking a larger role in hunting (ethically, of course, no need to maim the poor animals), & by restoring the populations of their former predators as best we can, something conservationists have had some success with for wolves here in North America.
Maybe the point is that humans are not actively planning, communicating, and altering our environment in a positive way to be able to handle the population increase.