Mobility is everything. The Service's Arizona Fishery Resources Office is similarly engaged. The East Fork White River is important habitat for two fishes, both federally listed as threatened, the loach minnow and Apache trout, an important sport fish. But a low-head dam that delivered irrigation water also blocked fish movement. The White Mountain Apache Tribe and Arizona Fishery Resources Office redesigned the dam to continue delivering irrigation water.
Flows are now concentrated midstream over a natural bottom that easily passes fish.
But even small structures if not properly placed can have big consequences on fish populations.