The grey wolf can sometimes be referred to as the timber wolf or the western wolf. While its population has dwindled due to human impact, it can still be found across large swathes of Eurasia and North America. It is also the largest wolf within its species. Males can attain weights of up to 45 kilogrammes and they can reach heights of 0.75 metres. They are also able to grow to well over one metre in length. Like all wolves, the grey wolf is a social and territorial animal. While rarely attacking humans, anyone who happens upon a mother and her young could be in danger.