Common in conservation news, especially about 大象 (elephants), 犀牛 (rhinos), 老虎 (tigers), and 穿山甲 (pangolins). Often paired with 反偷猎 ('anti-poaching') in NGO and government communications.
memory
偷 ('to steal') + 猎 ('to hunt') + 者 ('one who') = 'one who steal-hunts' = poacher. The 偷 makes it clear we're talking about illegal hunting, not just hunting (打猎 dǎliè).