Complex sentence: The bonytail chub, razorback sucker, Colorado pikeminnow, and humpback chub are among those considered the most at risk; all are unique to the Colorado River system and well adapted to the river's natural silty conditions and flow variations.
Split into simpler sentences: The bonytail chub, razorback sucker, Colorado pikeminnow, and humpback chub are among those considered the most at risk. All are unique to the Colorado River system and well adapted to the river's natural silty conditions and flow variations.