Massive Declines in Crooked River Fish Populations

Mon, 04 Dec 2023 21:01:58 +0000

The 2016 Oregon Department of Fish and Wildlife annual electro shocking survey of fish populations in the upper Wild & Scenic section of the Crooked River revealed that, during the past year, the wild redband trout population suffered a catastrophic 86.4 percent reduction in numbers while the native mountain whitefish mortality was an alarming 45.3 percent.

Last year when the Crooked River watershed was included within a regional drought-declared area, Bureau of Reclamation river flow decisions drained the Prineville Reservoir to its fourth-lowest level ever.

The rapid early winter reduction in flow suddenly decreased the width of the river and resulted in a significant loss of bank habitat for the aquatic bugs fish need to eat to survive.

Some Great Lakes Fish Populations at Risk from Low Nutrient Levels

Tue, 04 Jan 2022 22:00:36 +0000

As algal blooms flourish on the edges of the Great Lakes, lake management bodies look to cut down the flow of nutrients into the water that feeds the algae. But, as a recent report by the International Joint Commission explains, not all parts of the lakes suffer from too many nutrients — in fact, the deeper offshore waters aren’t getting enough.

In late June, the Commission’s Science Advisory Board released a report on the decline in nutrients in the offshore waters of the lakes and the harmful impact this decline is having on fish populations.

Phosphorus is an essential nutrient that fuels life in the Great Lakes ecosystems. The amount of phosphorus determines how many living things can survive in the lake, from tiny plankton up to top predator fish. And in every lake except Erie, the phosphorus levels in the offshore region — waters more than twenty meters deep — are below the targets established under the Great Lakes Water Quality Agreement between the United States and Canada.

fish population – Aquarius-Systems

Massive Declines in Crooked River Fish Populations

Some Great Lakes Fish Populations at Risk from Low Nutrient Levels