Bureau of Reclamation monitoring trout health as warming water in Lake Powell creates low oxygen levels downstream
Low water levels and rising temperatures in Lake Powell have federal officials concerned about the health of the trout fishery located near Lees Ferry.
The Bureau of Reclamation says warming, drying conditions have led to depleted levels of dissolved oxygen in the water, posing a threat to trout living below Glen Canyon Dam.
Native fish, like humpback chub and razorback suckers, aren’t being impacted as much because they are generally located farther downstream where low dissolved oxygen levels are remedied by riffles and rapids, which aerate the water.
The poor water quality immediately below the dam is mainly impacting the rainbow trout population located in that area, according to Colorado River managers.
Reduced oxygen in the water causes stress, increases metabolic rates and ultimately can result in fish kills or fish moving downstream to seek refuge in cooler, more oxygen-rich areas.
Prolonged drought and low runoff accelerated by climate change, have led to historically low water levels in Lake Powell and worsened ecosystem disruption in the river downstream of the dam.