Virtual Fish Tent: Lost Habitat


Railway Panel Flood Panel
Dams Panel Lost Habitat Panel
Salmon Lifecycle Restoration – Shifting Priorities
Restoration – A 15 Year Overview Restoration – A Learning Experience

The Lost Habitat! Headwaters above the dam…

The Scott Dam, which forms Lake Pillsbury is a complete barrier to salmonids – there is no fish ladder.The lake itself is a nursery for pikeminnow, and provides a constant supply of juvenile pikeminnow, as they get shot out of the needle valve at the base of the dam. Removal of the dam would take away the primary seed source for the pikeminnow invasion, and thus would treat the cause, rather than continually treating the symptoms of the problem.

Scott Dam Aerial

The Sacramento pikeminnow (aka “squawfish”) was first introduced to Lake Pillsbury as a bait fish in 1979. Since then, Pikeminnow have spread through much of the Eel River system, and today are present in most of the lower mainstem reaches, and some of the major tributaries. They prefer the warmer water habitats, and are very efficient predators – especially on native salmonids.

This pool is occupied by over 50 adult pikeminnow. They continuously roam the pool, looking for anything edible: native trout, smaller pikeminnow, and mice.

The area upstream of Lake Pillsbury is similar in size to some of the major salmon producing basins of north coastal California (200 – 300 square miles) – but it has been completely blocked off to migratory salmonids for nearly 100 years. Approximately 70 river miles that were historically used by salmon and steelhead are now home to the invasive pikeminnow and a few native trout. Imagine the outrage that would result today if someone tried to block off the entire Mattole River, Gualala, or Garcia River.

The upper mainstem of the Eel is a long, low-gradient channel suitable for spawning and rearing of native steelhead, coho and chinook salmon. The gravels are not as highly impacted by fine sediment as elsewhere in the Eel, and there is abundant pool habitat for rearing and growth. The unique characteristics of this reach of stream have long been recognized, but now are largely forgotten.
The upper headwaters of the Eel River passes through 2 large culverts, known as 2 Pipes. The pool below the culvert is occupied by native trout, and the area above isinhabited by pikeminnow. Lower water temperatures give the trout a slight advantage, and pikeminnow have a harder time getting over steep cascade reaches.

Blueschist boulders and red chert outcrops form hard points in the channel that create many deep pools in the mainstem Eel, above Lake Pillsbury. This habitat is off-limits to migratory salmon, due to the barrier at Scott Dam.

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