All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
Al-Fawaakih Ad-Dawaani (a Maaliki book) reads: “NB: Concerning all that we said is permissible to kill to ward off trouble, the killer is required to intend to kill it to ward off trouble, and to refrain from doing so in vain; otherwise, it will be forbidden (to kill it) even the harmful five pests, which are permissible to kill inside and outside the Sanctuary.” [End of quote]
This action is similar to inciting animals to fight each other and being amused by seeing them kill each other, which is forbidden.
According to the Majmoo‘ (of An-Nawawi): “Inciting animals to fight each other is forbidden based on the Hadeeth related by Ibn ‘Abbaas who said: ‘The Prophet, sallallaahu ‘alayhi wa sallam, forbade inciting animals to fight one another.’ Abu Daawood and At-Tirmithi reported it with an authentic chain of narrators, but it includes Abu Yahya Al-Qattaat and there is a difference of opinion about him being trustworthy, but Muslim reported from him in his Saheeh.” [End of quote]
Ash-Shawkaani said in Nayl Al-Awtaar: “It is forbidden because it causes pain to the animals and harms them without any benefit, but only for play.”
Allaah Knows best.