Miller Rocks Island-Avian Predation Remediation

Phase I of the Miller Rocks Islands Avian Dissuasion Project (MRI Project) will center on non-lethal dissuasion measures to address predation impacts within Zone 6 of Columbia River. The MRI Project area (Worksite #1) is a collection of rock outcrops above ordinary high pool located at Columbia River Mile 205 in The Dalles Pool. Currently, MRI supports a large nesting colony of California gulls (Larus californicus), and Ring-billed gulls (Larus delawarensis). A total of 4,284 adults were counted during the 2018 nesting season.



Recently completed FCRPS conservation measures includes an increased understanding of the need for expanded efforts to reduce losses of juvenile fish from predation by birds in the Columbia River. The CRSO BiOp highlights the impact of bird predation as major cause of mortality for ESA-listed juvenile in the Columbia River Basin. The BiOp identified performance standards for predation activities (combined birds, fish, and mammals) are 1.7% survival improvement for fall-run Chinook salmon, 3.1% survival improvement for other Chinook salmon, and 4.4% survival improvement for steelhead. The Project is intended to aid in these effort within Zone 6 of the Columbia River.

Non-lethal dissuasion techniques (wires, modifications to nesting sites, hazing, etc.) has been attempted by the US Army Corps of Engineers (USACE) for many years and many millions of dollars. Additional efforts have been conducted at The Dalles and John Day dams with some success. Avian dissuasion using green laser technology has been used for many years at commercial airports as well as in agriculture industry and has proven successful as a non-lethal determent to address avian impacts. It is well documented that MRI gulls feed voraciously on juvenile salmonids at the tailrace of The Dalles and John Day Dams, as well as nearby Zone 6 tributary deltas which have been drastically altered from hydrosystem development and have become significant “hot spots” for both avian and piscivorous predation.



Monitoring of this effort will rely on ongoing gull abundance and predation rate estimates (PIT tag recoveries) that are conducted annually by FPOM members. Project staff will provide project updates at Yakama Nation Fishers, CRITFC Commission, and FPOM meetings. Project and CRITFC staff in coordination with existing federal and state partners will attempt to haze gulls at any new start-up location. Within Zone 6, there are few suitable locations for a large colonies to persist, other than MRI. Phase I will begin with laser installation as soon as practical in 2021 and operation from April 1st to July 31st of each year to include the entire breeding season


Worksite #1 Proposed Work:

The Project team will deploy two solar-powered/battery backup green lasers (Avix Autonomic Mark II ) and program each device to cover the greatest surface area of the 5.5 acre rock outcrops on MRI. Project team will contract with the Bird Control Group for setup and periodic QA/QC of the two automated units. Year one the YN will test and familiarize our team with the technology. While deployed on MRI, the units will be inspected weekly throughout year one operation (April 1 – July 31 2022. Project staff will maintain laser units, solar arrays, and deep-cycle batteries. Laser units will be periodically inspected or on an on-call basis by technical staff from the Bird Control Group. Rock bolts and/or small concrete forms may be needed to anchor and support laser support structures.

The MRI Project is intended to eliminate or significantly reduce juvenile mortality attributed to the MRI gull colony within Zone 6 of the Columbia River. The project will benefit the following ESA-listed stocks; Deschutes River summer/fall Chinook ESU, Middle Columbia River spring Chinook ESU, Snake River Fall Chinook ESU, Snake River Spring/Summer Chinook ESU, Upper Columbia River Spring Chinook ESU, Upper Columbia River summer/fall Chinook, Middle Columbia River Steelhead ESU, Snake River Steelhead ESU, Upper Columbia Steelhead ESU, Okanogan River Sockeye ESU, and Snake River Sockeye ESU.