Actually, pets may be the animals least threatened by the effects of global warming, if they live in caring homes.

By contrast, as Noam Mohr said, wild animals are vulnerable to all kinds of changes in their environments, many of which they can do little or nothing to cope with; we see that many wild animals are already being affected by global warming.

Also, we cannot expect that much is likely to be done for the long-term health and comfort of farm animals, who are already used very roughly.

Still, pets whose human companions are themselves not capable of mitigating the effects of climate change may indeed find themselves at risk.

As one who lives with a dog, I worry as it is that although she and I occupy the same domestic environment, fairly safely and comfortably, there may still be unseen factors of sickness which may affect her more quickly than me.  Effects of climate change, such as increased hours of sunlight, decreased water resources, and extended ranges of disease-bearing organisms, are serious issues for all of us.  But it is certainly true that we need to take thought for how our pets may be peculiarly sensitive and at risk.

Chickens deserve our true friendship! So do fish! So do other sentient beings! Let us learn to be kind.