Thursday, June 30, 2011

Elwha River Bull Trout Rescue

This month, in preparation for removal of the Elwha and Glines Canyon dams, the U.S. Fish and Wildlife Service (FWS), U.S. Geological Survey, NOAA Fisheries, Washington Department of Fish and Wildlife, and the Lower Elwha Tribe participated in a multi-agency effort led by Olympic National Park to capture and relocate Elwha River bull trout from two reservoirs.

Lake Mills (formed by Glines Canyon Dam)
Removal of these large dams on the Elwha River will begin in September 2011 and is the largest dam removal project ever attempted in the United States. Although this historic dam removal will provide fish, including salmon and bull trout, access to 70 miles of pristine habitat upstream of the dams, the removal will also result in short-term water quality levels that are expected to be lethal to fish in the two reservoirs and the section of river downstream of the dams. The cause of the anticipated poor water quality is high turbidity resulting from the release of 17 million cubic yards of silt and gravel currently trapped behind the two dams and sitting at the bottom of the reservoirs where it has collected since the dams were constructed nearly 100 years ago. As a result, the FWS required Olympic National Park to develop and implement a bull trout rescue plan to move bull trout from this area during dam removal.

Helicopter lifting tote containing
40 bull trout destined for the
upper Elwha River
The rescue plan developed by Olympic National Park (and approved by FWS) called for the capture and relocation of up to 100 bull trout from the two reservoirs to locations upstream---Elkhorn and Hayes Rivers. The rescue operation collected 82 bull trout during a 10-day period using hook-and-line sampling and electrofishing techniques. We held the fish in live cages in the upper reservoir until they were flown by helicopter to the two upstream release sites on June 17. We collected a genetics sample and recorded length and weight for each fish in order to monitor how these fish respond to dam removal. We also tagged each fish to determine if the fish remain upstream where they were released or if they migrate back downstream. All 82 fish flown to the upper watershed release sites were alive and doing well at release. Detection of these fish later on will guide fish rescue recommendations for future dam removal projects in other western rivers.

For more information on this project, read the news release from Olympic National Park.


Wednesday, June 15, 2011

Anadromous Juvenile Bull Trout in the Skagit River, 1990-2009

Juvenile bull trout              (Photo: WDFW)
Bull trout are a member of the salmonid family, which includes salmon, trout, whitefish, char, and grayling. Salmonids are particularly known for their migratory nature. Anadromous salmon are an extreme case, spending most of their lives in the ocean but returning to headwater streams to spawn. Resident trout are at the opposite end of the spectrum, spending generation after generation in one stream. Between these extremes are migratory fish that never reach salt water, including adfluvial fish which spawn in streams but live in lakes, and fluvial fish which spawn in headwater streams but live downstream in larger rivers. Bull trout in Washington exhibit all ranges of this spectrum. Many are resident to a single stream, while migratory bull trout spawn in tributary streams where juvenile fish rear for 1 to 4 years before migrating to either a lake (adfluvial form), river (fluvial form), or salt water (anadromous) to rear as subadults or to live as adults. Bull trout are further unique in that individuals within a population can be anadromous while others stay in a river their entire life. Within one population, some fish may reside in tributaries, others migrate into lakes, and still others are anadromous.

Bull trout love cold, clean, complex, and connected streams and other aquatic habitat. Habitat degradation and fragmentation, blockage of migratory corridors, poor water quality, the effects of climate change and past fisheries management practices, including the introduction of non-native species such as brown, lake and brook trout, have resulted in local extinctions and population declines of bull trout (Salvelinus confluentus). This has led to the listing of bull trout as threatened under the Endangered Species Act in 1999. Within the Puget Sound Bull Trout Management Unit, there are eight core areas with a total of 57 local populations identified. Bull trout are found in the Chilliwack, Nooksack, lower and upper Skagit, Snohomish-Skykomish, Stillaguamish, upper Cedar (Chester Morse Lake system), and Puyallup River basins. With the exception of the Chilliwack and upper Cedar River systems, these basins all support anadromous bull trout that use Puget Sound marine waters for foraging and migration.

A high priority goal for the Puget Sound Management Unit is to acquire more complete information on the current distribution and abundance of bull trout within each core area. Additional information is needed on bull trout use of and distribution in estuarine and marine waters of Puget Sound. The anadromous form is unique to this recovery region and perhaps the least understood of all the life history strategies.

The goal of a joint effort between the U.S. Fish and Wildlife Service and Washington Department of Fish and Wildlife (WDFW) is to characterize anadromous juvenile bull trout migration and associated environmental variables in the Skagit River. The Skagit River watershed contains 26 of the 57 local bull trout populations and all four life history strategies. A juvenile fish trap operated by WDFW near Mount Vernon (see map below), has collected biological information on juvenile salmonid migrants since 1990. However, the data on bull trout has never been summarized, so we provided funds to WDFW to analyze the 19 years of data they had collected. WDFW recently produced a report of their findings, which includes:

  • On average, 186 juvenile bull trout were caught per season (see graph below).
  • The fish ranged in length from 90-290 mm, averaging 125-144 mm.
  • These fish move downstream primarily at night
  • Migration occurs between April and mid-July, with peak catches in late May.
  • The trap catch can be used as an index of abundance; however, the trap catch cannot be expanded to a total abundance estimate because it under-represents the larger fish.
  • Relationships may exist between anadromous juvenile bull trout and spawner abundance, rearing temperatures, and food availability. Low spawner abundance of pink and chum salmon combined with high stream temperatures may limit early growth of anadromous bull trout.

Bull trout are a diverse species with specific habitat requirements. Successful conservation and management of this species will require an accurate understanding of which habitats are important for bull trout growth and survival, as well as migratory corridors that connect critical habitats. Further understanding the anadromous life history strategy will help us conserve this unique component of the Puget Sound Bull Trout Management Unit.

Download the full report at:
Learn more about bull trout biology, critical habitat, and conservation measures at

Skagit River downstream trap and areas of known
bull trout spawning (WDFW)

Catch of juvenile bull trout in trap (WDFW)

Friday, June 10, 2011

Logjams for Salmon and Bull Trout in the Skokomish River

The Skokomish River is the largest source of fresh water for Hood Canal, a 70-mile natural fjord-like side basin of Puget Sound. It is also the most frequently flooded river in Washington State. The Skokomish River is home to four species of salmon and trout that are listed as threatened under the Endangered Species Act. After years of intense logging, road building and development in the watershed, strong partnerships have formed to turn the tide of worsening conditions and restore the river.

The U.S. Fish and Wildlife Service (FWS) provided funds to the Skokomish Tribe to complete one of the largest logjam projects in the Pacific Northwest. Through the support of many partners throughout Hood Canal, 30 massive man-made logjams were placed along 1 mile of the mainstem South Fork Skokomish River last summer. These structures were installed to stabilize streambanks, restore stream function, and improve aquatic habitat in a reach that had been cleared for a proposed reservoir in the 1950s. The goal of the project is to improve fish habitat by increasing pools and habitat complexity--large pools create microhabitats where fish can hide and stay cool. 

Logjam construction             (Photo: Skokomish Tribe)
 To create the logjams, over 2,000 second-growth trees were uprooted at upland sites and transported to the stream by helicopter. The trees averaged 100 feet long and were embedded far into the streambanks using excavators. Smaller trees and log sections were then carefully wedged in to create a very complex and dense logjam. Planting of trees along banks and within the floodplains has also begun and will continue in following years.

The structures were placed strategically in a section of the South Fork Skokomish that had few natural logjams. This area, approximately 11-14 miles upstream from where the Skokomish empties into Hood Canal, was heavily logged in the 1950's and 1960's in preparation for a dam that was never built. The lack of streamside structure allowed the river to subsequently grow wider and shallower, causing the water temperature to rise. The addition of these logjams should cause the water to carve out a deeper, more natural channel, result in cooler temperatures, and help retain spawning gravels for the fish to use. In addition, vegetation is likely to grow along the edges of the logjams, eventually shading the river and providing natural structure.

Fortunately, the logjams held up well to last winter’s storms and flooding. Few components of a small number of the jams were lost, while several of the structures even managed to collect additional logs that were floating downstream. As of April 2011, deep pools had already formed downstream of the logjams, creating places for fish to rest, find refuge, and feed. With these habitat improvements, the upper reaches of the Skokomish River should be able to support larger runs of threatened steelhead and bull trout. Additional benefits will accrue for federally-listed summer/fall and spring Chinook salmon, coho salmon, rainbow and cutthroat trout, and lampreys.

Before construction              (Photo: Skokomish Tribe)

After construction                (Photo: Skokomish Tribe)
The Skokomish Tribe sponsored this project. Partners included the U.S. Forest Service, TEAMS Enterprise, FWS, Hood Canal Coordinating Council, and the Skokomish Watershed Action Team. The Skokomish Tribe acquired $729,000 in Washington Salmon Recovery Funding Board and FWS grant funding for this project. The Forest Service contributed $525,000, which includes the value of the trees, planning and construction costs.

More logjams are needed downstream of the project area and construction will begin as soon as funding and approval is acquired.

Thursday, June 2, 2011

Pacific Lamprey Redd Surveys in the Chehalis and Willapa River Basins

Pacific lamprey, Lampetra tridentata, are very primitive, eel-like fish that historically were widely distributed from Mexico north along the Pacific Rim to Japan. They are culturally important to indigenous people throughout their range, and play a vital role in the ecosystem as food for mammals, fish and birds, for nutrient cycling and storage, and as a prey buffer for other species. Lamprey are also used for scientific research, educational purposes, vitamin oil, and anti-coagulants.

Pacific lamprey spawning 
(Photo:  K. Figlar-Barnes, WDFW)
Pacific lamprey are anadromous, meaning that they live in both fresh and salt water. Adults are parasitic and live in the ocean where they feed on the blood and bodily fluids of marine mammals and fish. After about 2 years in the ocean, they return to fresh water streams to spawn. After entering fresh water, the adults either stop feeding and spawn or they overwinter and spawn the following spring. Lamprey construct nests (redds) in small gravel where they lay their eggs. Like salmon, lamprey die soon after spawning. Eggs hatch after several weeks and the blind larvae are called ammocoetes. The ammocoetes live in fine sediment, filter feeding on algae and detritus. After 4 to 6 years as an ammocoete, Pacific lamprey metamorphose to a juvenile life stage called macropthalmia. The juvenile lamprey migrate out to the ocean where they mature into adults, growing to about 2 feet in length.

Pacific lamprey are vulnerable to many of the same threats that have reduced salmon populations. These threats include poor habitat conditions, water pollution, and dam passage. Like salmon, the abundance and range of Pacific lamprey have been reduced. To improve their distribution and abundance, we are working with our partners to address threats, restore habitat, and fill in large data gaps on Pacific lamprey. One of the data gaps we are currently addressing is the distribution and abundance of spawning lamprey in Washington coastal rivers in the Chehalis and Willapa River basins.

Beginning in March and continuing through June, Washington Department of Fish and Wildlife (WDFW) biologists and scientific technicians conduct spawning ground surveys to estimate natural spawning steelhead populations. The survey crews identify and monitor steelhead redds and, since 2005, have also been counting any Pacific lamprey redds and adults they see during these surveys. Because some of the steelhead index survey coverage does not include the Pacific lamprey spawning timing, we contracted with WDFW  in 2010 to cover the lamprey spawning period from June through August.

For this project, WDFW selected 30 (50%) of their 60 steelhead index reaches to survey for lamprey. Indexes were selected based on previous years’ lamprey spawning timing, redd density, habitat type, location within the basin, and proximity to other indexes. Similar to the steelhead program, surveys were conducted every 10 to 14 days and began on June 1. Survey staff were instructed to record all visible Pacific lamprey redds along with any live or dead adults they saw. This visible redd count data provides relative abundance estimates and spawning timing data.

Mid to late July appears to be the end of the spawning time period for Pacific lamprey in both the Willapa and Chehalis basins; 28% of the visible lamprey redd activity occurred after the WDFW cut-off date used for steelhead spawning ground surveys. A total of 539 redds were observed in 2010---this is very encouraging as it is an increase compared to the previous 2009 spawning season (see graph below). However, the 2010 redd count data was down by an estimated 37% compared to the average number of redds over the 2005-2009 spawning seasons.

As funding allows, we hope to continue these extended Pacific lamprey redd surveys in the future so that we can use this data to monitor the status of these fish populations.

For more information on FWS Pacific lamprey activities:

Coloring book:

Pacific lamprey fact sheet: