Complex sentence: Later, this population declined from an estimated mean population of 59,000 in 1995 to 11,600 in 2009, a reduction attributed largely to hotter and drier conditions resulting from droughts in most years between 2002 and 2007.
Split into simpler sentences: Later, this population declined from an estimated mean population of 59,000 in 1995 to 11,600 in 2009. This 80% reduction is attributed largely to hotter and drier conditions resulting from droughts in most years between 2002 and 2007.