Complex sentence: The numbers were reduced from an estimated 40,000 to 200 in 1950, however they were never fully eradicated; an increase in leisure time and greater ease of access to the mountain side drove an influx of hunters who saw the remaining feral species as game animals.
Split into simpler sentences: The numbers were reduced from an estimated 40,000 to 200 in 1950. However, they were not fully eradicated; an increase in leisure time and greater ease of access to the mountains drove an influx of hunters who saw the remaining feral species as game animals.