SENATE COMMITTEE ON ENVIRONMENT AND PUBLIC WORKS
SUBCOMMITTEE ON DRINKING WATER, FISHERIES AND WILDLIFE HEARING
Washington, DC
October 8, 1998
Testimony of Colonel Eric Mogren, Deputy Commander
Northwestern Division
US Army Corps of Engineers

Good morning, Senator, Committee members, and distinguished guests, I am Colonel Eric Mogren, Deputy Commander of the Northwestern Division of the US Army Corps of Engineers. I appreciate the opportunity to testify today on topics of interest to all of us in the Pacific Northwest who have devoted much energy and resources to preservation and restoration efforts for declining stocks of salmon and steelhead.

My testimony addresses avian predation and turbine passage improvements, topics within the Corps' scope from among those listed in your agenda for today's hearing.

The topic of avian predation on juvenile salmonids in the Columbia River Estuary is of particular interest to the Corps. Recent research has indicated that colonies of Caspian terns, gulls, and cormorants in the estuary are consuming salmon and steelhead smolts as the young fish make their way to the ocean.

Caspian terns nesting on Rice Island are protected by the Migratory Bird Treaty Act. Our efforts must focus on finding a balance so we can provide suitable habitat within which both Terns and salmonids can survive and prosper. Protection of the terns has been a concern raised to us by the Audubon Society, the Pacific Seabird Group, and the American Bird Conservancy.

Many populations of salmon and steelhead in the Pacific Northwest are in serious trouble, with several listed as threatened or endangered under the Endangered Species Act. Extensive effort by the Corps and other federal, state, tribal and private entities in the region have shown some positive results, but more effort is needed. The region has invested many millions of dollars over several decades to save this important resource.

Rice Island was created in 1962 by placement of dredged material. It is located 21 miles upstream of the mouth of the Columbia River. Over the years, it has become a nesting site for thousands of gulls, cormorants, and since 1387, Caspian terns. Rapid increases in Caspian tern nesting colonies were noted in the early 1990s.

Due to concerns about avian predation on the young salmon as they moved through the estuary, National Marine Fisheries Service' (NMFS) Biological Opinions on salmon and the hydropower system included a request for the Corps to evaluate avian predation in the Columbia River system. We contracted for this work with some very capable researchers, including Doctor Daniel Roby of Oregon State University, who is also here today to testify. And largely through your efforts, Senator, language in the 1996 Water Resources Development Act also recognized a potential need for research and development activities related to "estuary and near~ ocean juvenile and adult salmon survival."

Results from the 1997 field research season alerted the region that avian predation may significantly affect juvenile salmonid survival in the estuary. It was estimated that Rice Island supported the largest known Caspian tern colony in North America, with over 16,000 birds in 1997. Preliminary research results from 1998 indicate that the colony has grown again by approximately 25 percent to 20,000 birds. Further, it was estimated that these birds in 1997 consumed from six to 25 million juvenile salmonids annually. This estimate is supported by two other research activities we funded: juvenile fish radio tracking studies; and the reading of passive-integrated-transponder, or PIT tags, found on Rice Island that had been inserted into the juvenile fish at upriver facilities. However, available science cannot yet tell us the impact of the level of predation on the recovery of listed salmon.

In a March 24, 1998 letter, NMFS requested that the Corps ''take action at implementing a short-term remedy to minimize predation on the 1998 [salmonid] outmigrants." In response, a Caspian Tern Working Group has been established that includes the Corps, NMFS, University researchers, Columbia River Inter-Tribal Fish Commission, Oregon and Washington Departments of Fish and Wildlife, Bonneville Power Administration, and US Fish and Wildlife Service.

This group has identified a potential near term plan to attempt to relocate the Caspian tern colony from Rice Island to East Sand Island, an island approximately 16 miles downstream from Rice Island. East Sand Island is where the birds first settled when they came to the Columbia River Estuary in 1384. Research on cormorants supports assumptions that terns that feed downstream from Rice Island may eat fewer salmonids and more of other fish species. In addition, studies of cormorants from Rice Island versus East Sand Island also indicate that the East Sand Island birds consume fewer juvenile salmonids as a portion of their diet.

To move the birds, several actions are planned before the start of the 1999 nesting season. Habitat on East Sand Island will be developed that is attractive to the terns. Because the birds nest on bare sand, the island will be scarified to remove vegetation and debris. Decoys and calls will be used to attract the birds to East Sand Island.

The birds will be dissuaded from settling on Rice Island by alternatives such as habitat alteration, to be accomplished by seeding with wheat, grasses and legumes: and/or non-lethal disturbance of the birds to disrupt nesting and feeding patterns. A monitoring program will be implemented to assess effects on the terns and to verify reduced salmonid predation.

Environmental documentation in compliance with the National Environmental Policy Act, or NEPA, will be completed prior to implementation of this plan. The Corps is drafting an environmental assessment under NEPA to address these actions. We are also preparing to implement habitat development on East Sand Island, and establish vegetation on Rice Island to help dissuade the birds from nesting on these islands.

The plan is not without controversy. The birds have their supporters as do the salmon. I believe the proposed plan balances these concerns, but we will see what responses we receive when we issue the environmental assessment toward the end of this month.

I have been working with the other federal officials, namer: Will Stelle from NMFS and Ann Badgley from Fish and Wildlife Service, to share the responsibility for this issue. While this :

a multi-agency effort involving some of the best experts in the field, there is no guarantee that this near term plan is scientifically supportable at this time, or that the plan will be fully successful. This attests to the need for a combined agency approach to a long-term solution to this problem.

I would like to address now the topic of safer turbine passage for juvenile fish. While juvenile fish bypass systems, increased spillway passage, and truck and barge transport for juvenile fish have greatly improved juvenile fish passage at the Corps' eight lower Columbia and Snake river dams, a percentage of fish continue to pass the dams through turbines. The survival rate for turbine passage is estimated at between 89 and 94 percent. While this may seem to be a good survival rate, it diminishes considerably when multiplied by passage through as many as eight dams.

The Corps currently has a turbine passage improvements program under way as part of its Columbia River Fish Mitigation (CRFM) project. This turbine program developed from a Turbine Passage Survival workshop we held in 1995 to discuss with experts the possible mechanisms affecting survival of juveniles through turbines. At that time, we were in the process of rehabilitating the turbines at Bonneville Dam First powerhouse; Voith is our primary contractor.

An idea that developed that is now incorporated into the design of the Bonneville Dam rehabilitation is the concept of minimum gap runners. It is believed that this design change will result in improved juvenile survival. We will have the first units available in 1999 for testing of this concept.

In addition, in 1997 we initiated a Turbine Passage Survival Program under CRFM. This is a four-year program to identify potential areas of injury to fish in turbine passage and to design better turbines to reduce this injury. Our plan includes model studies and, if warranted, the field testing of prototypes. We have recently released an annual report that addresses the direction of this program. Under the constrained FY99 appropriation to CRFM, some of the turbine studies program activities may not be funded. In coordination with regional interests, we are presently determining which actions will be able to continue in FY99.

Thank you for the opportunity to participate in today's hearing. I will be happy to answer any questions you may have.