This is the lowest level pet to come with screech level 2. This makes it very good at holding aggro - even from muliple mobs, although it is a melee aoe effect and you may need to disable if crowd control measures are being used by other party members.
The last post is not really correct, this pet may have armor/stamina a bit less than a boar but it is much better at holding aggro from dps or healers, especially when taking on multiple mobs. Therefore it is extremely good at tanking - if you consider tanking to be mainly about aggro management.