G15PS00329_SOW.docx

Project Description of Nets/Services

Project:

Lake Trout Removal and Bull Trout Conservation in the Logging Lake Drainage, Glacier National Park, Montana and Continued Lake Trout Suppression in Quartz Lake, Glacier National Park, Montana.

Background:

The U.S. Geological Survey (USGS), Northern Rocky Mountain Science Center and National Park Service (NPS) are beginning lake trout suppression and bull trout conservation in Logging Lake, Glacier National Park (GNP) to protect the federally threatened bull trout and other native fish. Additionally, the USGS and NPS are continuing lake trout suppression efforts in Quartz Lake, GNP. This work requires netting lake trout with equipment and techniques proven effective to remove lake trout from high mountain glacial lakes while minimizing impacts to native fish and wildlife species.

The gill nets described below consist of combinations of monofilament twine diameters, stretch mesh sizes, and net panel dimensions that have proven effective in exploiting juvenile and adult lake trout while minimizing native species bycatch in Glacier National Park (Quartz Lake, 2009

- 2013) and elsewhere in the Rocky Mountain West such as Yellowstone Lake and Lake Pend Oreille, Priest and Upper Priest Lake, and Swan Lake.

Description of Specific Items/Services to be Purchased:

Juvenile lake trout suppression nets: Juvenile lake trout suppression nets will be 6' in depth and 300' in length with monofilament twine hung according to custom hanging ratios. All phrases or ties will be 8" or less to minimize tear-out and increase the life of nets. Nets will consist of a ¼” diameter lead line with a 30# lead core, a ½” diameter poly foam line with floats every 6', breast/bridle lines constructed from ¼” hollow core poly line. Juvenile lake trout suppression nets will be hung with 0.10 or 0.15 mm diameter monofilament twine (specified by the USGS) that is light green tint in color. The mesh stretch diameter of each net will be geared toward the capture of juvenile lake trout and will range from 1.5'' to 3.0" in ½” increments. These nets will be purchased both as "new" and as "refill-reconditioned". Refill-reconditioned nets will be purchased at a discounted price and will consist of the lead, float and bridle lines of previously used nets but will hung with new 0.10 or 0.15 mm diameter monofilament twine.

Adult lake trout suppression nets: Adult lake trout suppression nets will be 12' in height and 300' in length, with monofilament twine hung according to custom hanging ratios. All phrases or ties will be 8" or less to minimize tear-out and increase the life of nets. Nets will consist of a ¼” diameter lead line with a 30# lead core, a ½” diameter poly line with floats every 6', breast/bridle lines constructed from ¼” hollow core poly line, and 0.23 mm diameter monofilament twine that is white in color. The mesh stretch diameter of each net will be geared toward the capture of adult lake trout and will range from 4.0" to 5.5" in ½” increments. These nets will be purchased both as "new" and as "refill-reconditioned". Refill-reconditioned nets will be purchased at a discounted price and will consist of the lead, float and bridle lines of previously used nets but will be hung with new 0.23 mm diameter monofilament twine.

Delivery: Nets are to be delivered to the USGS Northern Rocky Mountain Science Center, Glacier Field Station, West Glacier, Montana or shipped to our offices using a provider of our choosing.

Consultation: Consultation will be necessary to provide expertise and training to USGS biologists and field technicians. Services will include field site visits and on-call customer service regarding mechanical problems related to gill nets, boat and motors, and hydraulic net lifters that may be encountered during the course of the projects. Services will also include consultation and discussion of gill net performance regarding lake trout suppression and reduction of bull trout bycatch (and other native species). Consultation on gill net performance will allow biologists to discuss in detail any changes in net deployment that may improve suppression efforts or reduce bycatch ratios and request minor adjustments to net construction that may improve performance.