California sea lion (Zalophus californianus) abundance and their impacts on listed salmonids (Oncorhynchus spp) have increased dramatically at Bonneville Dam over the last 5 years.  So much so that in 2008 NOAA Fisheries granted the states of Oregon, Washington, and Idaho lethal removal authority under section 120 of the Marine Mammal Protection Act (NOAA 2008a).  This authority is currently being litigated but the parties have agreed to a schedule that would complete proceedings prior to March 1, 2009, thus effective prior to the next salmon run.  Actions proposed in this narrative are independent of the lethal take litigation and are supported and deemed important by all parties.  If the states retain lethal take authority from NOAA for removal of sea lions, implementation will require the states to transfer much of their efforts towards animal capture, which will reduce their effort available for non-lethal hazing and other activities.  This project allows us to take up some of the slack in the non-lethal hazing component, provide some assistance to the states with capture efforts, plus implement a project to estimate sea lion predation in areas outside of the Corps observation area, and track movements (at various scales) of individual animals.

This project will be collaborative with the States of Oregon and Washington, ACOE, and USDA.  The scope of the project includes a 3 person, boat-based, sea lion hazing crew operating 5 days a week for approximately 3 months near Bonneville Dam.  This crew will conduct non lethal sea lion hazing, assist with trapping, and other field duties.  A second objective will be implementing a project to estimate sea lion predation outside of the ACOE observation area.  The ACOE observation project is limited to the Bonneville Dam tailrace area that is viewable from the deck of the Dam.  The notion is to adapt video fish counting technology that we have developed to enumerate sea lions and salmon predation.  A video system will be deployed to observe river surface activities in quantified areas of the river.  Software will be used to scan recordings and select times when water surface disturbances are detected.  Technicians will then review these time periods and note sea lion presence and predation activities.  An additional video system will be deployed within the Corps observation area to evaluate effectiveness of the fine scale near Bonneville Dam and at a coarser scale throughout the lower Columbia River using acoustic telemetry.  Observations regarding affinity to particular feeding stations, fine scale movement of animals in the area near Bonneville Dam, and coarse scale movement of animals downstream in the lower Columbia River will be made.  

Objective 1.  Conduct boat-based non lethal sea lion hazing annually generally between March 1 and May 31.
Objective 2.  Develop a video system to enumerate sea lions and estimate predation.
Objective 3. Track movements of individual sea lions at various spatial scales in the Columbia River using acoustic telemetry.

METHODS

Boat hazing activities will occur during daylight hours between the Bonneville Dam face to 6 miles downstream.  The hazing boat will be crewed by three people (one boat captain, one data collector and one person hazing), and will coordinate activities with the state hazing boat (WDFW) and Department of Agriculture hazing crews on Bonneville Dam.  Hazing will be boat-based and include acoustic and tactile deterrents (seal bombs, cracker shells, rubber buckshot, and vessel chase) in an attempt to deter pinnipeds.  

Data on all sea lion encounters will be recorded following protocols established by the states which include the time and location of the initial encounter, species, direction of movement, fish kill information, numbers and types of deterrents used, and time, location and direction at the end of the encounter.  All data collected will be sent to ODFW/WDFW to be included in the overall hazing evaluation.  In-season activities are summarized on a weekly basis by the Corps.  Included in those summaries are effects from boat-based hazing.  A collaborative annual report is also produced which details the project.  All activities funded by the BPA will be included in this collaborative report.  For an example of the report see Wright et al. (2007).

Project participants receive safety briefings from CRITFC, USACE, ODFW, and WDFW personnel.  Briefings cover boat operations and clearance for activities in the Boat Restricted Zone (BRZ) below the dam, overhead hazards, lockout procedures, hazardous water conditions, personal safety equipment (PFDs, ear and eye protection), communications, and project planning details.  A safety protocol for pyrotechnic deployment from the boats will be discussed.  Boat teams receive briefings on vessel safety equipment and rescue procedures at the time of launch.  While inside the Boat Restricted Zone (BRZ), hazing boats maintain VHF-radio contact with the Bonneville Dam Vessel Control officer for status and vessel traffic updates.

We propose to develop a system for estimating sea lion predation outside of the Corps observation area using video surveillance technology.  This will be an extension of the video fish counting systems that we pioneered in early 1990’s (Hatch et al. 1994, 1998) that is currently being used at numerous locations in New England (Haro and Fryer 2006), Michigan, Oregon, Alaska, and Europe.  One video system would be deployed to observe river surface activities in known areas of the river.  The camera system will scan the surface recording low and high resolution images that will be recorded on a computer.  Fish counting software would be used to scan recordings and select only the times when water surface disturbances are detected.  Technicians would then review these time periods and note sea lion presence and predation activities.

The acoustic telemetry project will work in concert with existing telemetry arrays already maintained by CRITFC (BPA project 2007-401) and the Oregon and Washington sea lion capture and branding efforts.  This project will use similar methods to Wright et al (2007) which studied feeding behaviors of Harbor Seals on the Alsea River using acoustic telemetry. Vemco acoustic transmitters will be externally attached to newly captured individuals with the cooperation of the states’ trapping effort.  Based on past trapping efforts, we expect to tag 12 to 15 animals in the initial year.  Acoustic hydrophones will be set up in several arrays near each of the tailraces of Bonneville Dam and in several locations between the dam and marker 85.  Existing arrays are located on the Columbia River at Rkm 0, 53 and 140.

OUTCOME/OBJECTIVES:

1. Hazing activities will attempt to deter sea lion presence near Bonneville Dam and its fishways in an attempt to reduce predation on ESA listed spring Chinook and steelhead.

2. Data collected will be added to the existing state, USACE, and NOAA databases concerning sea lion presence away from the ocean, predation on ESA and non-ESA listed fish species, and the effectiveness of hazing on deterring sea lion presence.  Data collection and reporting will be consistent with and included in a field report similar to last year (Wright et al. 2007).

3. Proof of concept of a video-based system to estimate abundance of and predation by sea lions in the lower Columbia River.  

4. Using hydroacoustic telemetry, coarse scale movements of tagged individuals will be recorded as they migrate between the ocean and Bonneville Dam.  Finer scale movements near the dam should provide diurnal feeding habits, duration and preferred location of feeding sites, number of feeding and resting cycles in a given day, and detection efficiencies of visual and video enumerations.

ENVIRONMENTAL COMPLIANCE

Permits under the MMPA Section 109(h)(1)(c) will be issued to the states for this work.

REFERENCES

Bryan Wright, Steve Jeffries, Robin Brown, Robert Stansell, Doug Hatch, and Brent Norberg. 2007.  FIELD REPORT – NON-LETHAL PINNIPED DETERRENT ACTIVITIES AT BONNEVILLE DAM, SPRING 2006.  STATUS REPORT TO NOAA.