Aerial view of Little Port Walter, showing Inner and Outer Bays, Sashin Creek, and Sashin Lake. Photo taken at mid-tide, August 1961, by Auke Bay Laboratories.
NOAA's Little Port Walter (LPW) Marine Station on Baranof Island in Southeast Alaska celebrates 75 years of fisheries research this summer. Established in 1934, it is the oldest year-round biological field station in Alaska and has fostered more than 200 scientific publications, documents, and reports on marine resources of this region. The LPW station also has maintained an official daily weather record for the National Weather Service since 1936. It is one of the wettest recording stations in North America, averaging 240 inches of precipitation annually.
Located in lower Chatham Strait 20 miles form Cape Ommaney and the open Gulf, the station is well suited for detailed research on many species. It is also an ideal location for measuring long-term biophysical parameters related to impacts of climatic factors such as changes in precipitation profiles, freshwater and sea surface temperatures, and near-shore salinity patterns. As part of the larger Big Port Walter Fiord, Little Port Walter consists of Inner and Outer Bays. Sashin Creek, a productive salmon stream for several species of salmon including steelhead, flows into the head of Inner Bay.
Historical Setting
In 1917, Little Port Walter was the site of the first Wakefield Fisheries processing plant in the territory of Alaska, a major seafood processer throughout the state. In 1925 a young college graduate, George A. Rounsefell, was sent to the Wakefield plant by the U. S. Bureau of Fisheries (USBF) with an assignment to study the large herring fisheries and the many herring processing plants operating in that region.
At about the same time Rounsefell's supervisor, Dr. Fred Davidson, in charge of all USBF research in Alaska, was developing a field station to study pink salmon at Snake Creek near Wrangell, Alaska. Rounsefell, after studying herring at LPW and the Chatham Strait region for a few seasons, also saw the annual runs of pink, chum, and coho salmon that migrated into Sashin Creek at the head of LPW Bay. By the early 1930s he convinced officials to move the Bureau of Fisheries salmon research to LPW so Federal salmon and herring researchers could work out of the same location.
Little Port Walter Marine Station headquarters, commonly known as "the White House." Historical photo, mid-1950s-'60s. Photo by Auke Bay Laboratories.
Sam Hutchinson, a recent University of Washington graduate at the time, with the help of Edward Dahlgren and LeRoy Christey, established a temporary salmon counting weir on Sashin Creek at LPW in 1934. Supplies, building materials, and equipment were brought to the site on the USBF vessel Heron. A small one-room weir building was constructed on Sashin Creek in 1934. (After restoration in 2005 the building remains in use today). Hutchinson counted upstream migrating adult salmon with a series of temporary weirs near the mouth of the stream.
In 1938 the U.S. Congress passed legislation authorizing the establishment of a permanent fishery laboratory at LPW for "an orderly program of fishery investigation." This act provided funds for building a permanent weir and more substantial living quarters. In 1939 using Civilian Conservation Corps (CCC) workers, Hutchinson constructed a permanent concrete weir in the upper intertidal zone of Sashin Creek that was capable of counting both upstream adult and downstream migrating juvenile salmon.
During the 1930s, scientists were just beginning to fully appreciate the fixed 2-year life cycle pattern of pink salmon and recognized the need for more detailed life history knowledge on this species. With the ability to count numbers of pink salmon fry migrating downstream past the Sashin Creek weir that were produced from a given number of adults, researchers were then able to determine freshwater survival values for different broods of Sashin Creek pink salmon.
Knowing precise numbers of fry going to sea from each brood also provided a data point for estimating marine survival based on the number of adults returning from that brood. Marine survival estimates, however, did not include the unknown effects of commercial fisheries. Some 40 publications and reports involving Sashin Creek pink salmon have provided a wealth of detailed information on this species.
In 1940 Hutchinson used bricks from across the bay from the then abandoned Wakefield processing plant, along with a $5,000 budget and help from U.S. Forest Service and CCC workers and constructed the three-floor LPW headquarters building, commonly referred to as "the White House." Since construction of the building, a permanent fishery technician has been stationed at LPW on a year-round basis. In 2004 funding was provided to completely renovate the exterior of the LPW White House.
Research History
Research priorities at LPW can be divided roughly into two periods. For most of LPW's first 40 years, studies focused primarily on the ecology, population dynamics, and life histories of Sashin Creek fishes including pink, chum, and coho salmon, steelhead trout, Dolly Varden char, and Coast Range sculpins. Initially, research focused on environmental factors that affect freshwater survival of pink salmon.
Environmental conditions were unusually harsh at Sashin Creek in the 1940s, including both dry spells and flooding. In the late 1950s scientists began to notice that although few adult pink salmon spawned in the upper part of Sashin Creek, this area produced the most fry, an observation leading to research that documented the importance of substrate type and stream gradient on egg and fry survival. The collective knowledge on the ecology of Sashin Creek provided the basis for determining the optimum numbers of adult pink salmon needed to produce the maximum number of fry.
In the early 1970s, the state of Alaska embarked on a major fisheries enhancement program involving both public and private hatcheries. The result was an extended period of cooperative enhancement research at LPW with the Alaska Department of Fish and Game (ADF&G) and private hatchery groups. The initial period of enhancement studies at LPW involved coho, pink, chum, and sockeye salmon. Several novel technologies evolved from this research, including development of floating raceways, estuarine net pens for short-term rearing of fry, substrate incubation systems, vaccination studies on smolts for improved marine survival, and stocking fry in hanging lakes for natural smolt production.
Chinook Salmon Research
By the late 1970s as prospects for a comprehensive salmon treaty with Canada loomed on the horizon, the ADF&G and the state of Alaska requested that NMFS begin Chinook salmon enhancement research at LPW. Beginning in 1976, Chinook salmon eggs from two Behm Canal stocks on the Chickamin and Unuk Rivers were transported to LPW to start long-term research projects with these two stocks. Initially the principal research focus was for development of broodstocks and hatchery technology in support of the prospective salmon treaty with Canada.
A permanent weir on Sashin Creek in Little Port Walter has been operating every year since 1940. Photo shows gates and weir racks at LPW, 23 April 1956. Photo by Auke Bay Laboratories.
The U.S./Canada Pacific Salmon Treaty was finally ratified in 1985. Since then, Chinook salmon research at LPW has evolved into broader applications of importance with this species. Both the Chickamin and Unuk stocks, now in their sixth and seventh generations at LPW, are maintained separately by discretely marking all released smolts and by decoding anadromous adult spawners before mixing gametes.
These two stocks exhibit significant life history differences that make them important research tools for many issues of coast-wide concern. Surplus eggs from LPW research have provided stock-specific Chinook salmon founder populations at several Southeast Alaska production hatcheries, along with advanced technology for improving marine survival and maximizing contributions to Alaska commercial and recreational fisheries.
Since 1997, Chinook salmon research at LPW has focused on hatchery-wild stock interactions including inbreeding and outbreeding depression, domestication, and biological shifts in life history parameters. These studies involve introducing wild stock gametes from the original founder populations into components of each of the two LPW stocks. Currently research is directed at full parental genotyping involving sophisticated genetic techniques evaluating performance of individual families including marine survival and contributions to fisheries. This research also is testing the feasibility of genetically identifying specific stocks in fisheries.
Steelhead Research
In 1926 personnel at the Wakefield herring and salmon plant at LPW transplanted juvenile steelhead from the anadromous run in Sashin Creek upstream above two falls into Sashin Lake. This action established a self-sustaining freshwater population of rainbow trout in the lake. After 20 generations in the lake (83 years) Sashin Lake rainbow trout are still producing some steelhead smolts that migrate downstream and contribute to components of the anadromous run in Sashin Creek. Rainbow trout from Sashin Lake were also stocked in nearby Round Lake and several other lakes in the region in the early 1930s.
Although there are no ESA-listed steelhead or salmon populations in Alaska, the developments at Sashin Lake and Sashin Creek provided unique research opportunities at LPW for potential ESA recovery options in other areas. The NMFS Protected Species Program began providing limited funds to pursue this line of research beginning in 1996 and continues today. This research, in collaboration with several universities and other NMFS Science Centers, has produced numerous cutting-edge scientific publications and documents relative to the genetics of Sashin Creek steelhead and Sashin Lake rainbow trout along with potential applications for ESA-related steelhead and salmon recovery programs in the Pacific Northwest and California.
Other Studies
Floating raceways and net pens provide a place for raising juvenile salmon and steelhead at Little Port Walter. Photo by Auke Bay Laboratories.
Over the years research at LPW also has included detailed studies on shrimp, herring, oceanography of the Inner and Outer Bays, climatic changes, effects of environmental perturbations such as droughts and floods on fishery resources in the region, a 63-year daily weather record, and original studies on the intertidal ecology of spawning salmon. Shrimp research documented the importance of the Inner Bay at LPW as a nursery for juvenile spot shrimp during their first 2 years before they move into deeper waters and reach maturity. Studies on pink-coho salmon interactions in Sashin Creek lead to classical life history work on Alaska coho salmon and later to enhancement research with this species.
Detailed research on the impacts of low dose oil in experimental salmon spawning gravels at LPW documented deleterious impacts on eggs, juveniles, and adult salmon when exposed to extremely low concentrations (5.4 ppb) of polynuclear aromatic hydrocarbons. These were exposure levels far below what previously had been assumed safe for marine resources.
Recent studies in the LPW Behavior Laboratory documented important behavioral changes and substrate preferences in juvenile rockfish following simulated seafloor pertubations from fishing activities. Current studies are also under way on measuring marine coral growth rates in Chatham Strait at the entrance to LPW station.
The LPW Facility
Today the LPW marine station includes a marine dock and float system, a permanent fish counting weir at the mouth of Sashin Creek, a warehouse, two residences, the three-story headquarters building (with a galley, dormitory, small laboratory, radio room, and apartment), two wet laboratories, an experimental fish culture system with floating freshwater raceways and marine net pens, a generator building, an oil storage and containment structure, an incinerator, a NOAA weather station, and other support buildings.
The original small building Sam Hutchinson built at LPW is still in use. It is the small, green, one-room weir cabin with a metal plaque over the door post indicating "USBF-1934". Currently two NOAA employees are on-site year around, with other scientists, contractors, volunteers and personnel from other agencies or the private sector swelling the ranks to about 20 individuals at peak times.
