August 14, 2003
Contact: Doug Williams, 360-902-2256
North Fork Nooksack River watercraft ban starts Aug. 18, 2003 to protect spawning chinook salmon
A temporary rafting and boating closure will be in effect beginning at noon on Aug. 18, on a section of the North Fork Nooksack River in Whatcom County to protect spawning spring chinook salmon, a federally protected species, according to John Phipps, Forest Supervisor of the Mt. Baker-Snoqualmie National Forest.
The closure will be just east of Glacier extending from the Highway 542 bridge near the Douglas-Fir Campground, downstream about 2-1/2 miles to the National Forest boundary, located about one-quarter mile upstream from the mouth of Cornell Creek.
The temporary ban, deemed necessary to protect vulnerable spawning salmon from boats and other recreational disturbances, applies to all private and commercial boating and rafting during a period of high recreational floating activities. Commercial rafting guide operators have been notified of the closure so that contingency plans can be arranged.
A similar temporary closure was required last August due to a combination of receding river levels and a concentration of spawning chinook. This action is taken in cooperation with the Washington Department of Fish and Wildlife and NOAA Fisheries (National Marine Fisheries Service). Puget Sound chinook were listed as threatened under the Endangered Species Act in 1999.
North Fork Nooksack River
Watercraft Closure to
Protect Chinook Salmon
Due to a combination of receding river levels and a concentration of spawning chinook, a temporary rafting and boating closure is in effect on this section of the North Fork Nooksack River beginning noon, August 18, 2003. The closure is necessary in order to provide protection to "threatened" North Fork Nooksack chinook and to meet USDA Forest Service mandated responsibilities under Section 7 of the Endangered Species Act.
The closure was implemented due to the following factors:
- The level of the NF Nooksack River continues to drop and clear up in August;
- Lower river flows were concentrating chinook spawning in areas where they were vulnerable to disturbance from boaters (spawners were actually observed to move off redds when boaters came nearby);
- Chinook spawners continue to move into this reach;
- The confined (canyon) nature of this section of river makes it impossible for boaters to portage around and avoid spawning areas.
The closure is needed again this year in order to provide protection to the spawning NF Nooksack spring chinook, a federally protected species.
Chinook Life History
The NF Nooksack chinook is a native stock with adults averaging 20 to 25 pounds and typically spawns in its fourth year of life. Run timing is usually from July through early September and spawning typically starts in early August and continues into late September. The North Fork chinook stock tends to spawn earlier than the South Fork Nooksack stock.
Spawning, or redd (spawning nest) building, is a lengthy process taking 15 to 20 days to complete and includes the following three stages:
- Pre-spawning - Over a period of five days, the female selects a spawning site and begins a set of tentative redd excavations. She may retreat to areas of cover adjacent to her test excavations and be difficult to observe. Disturbance from boat traffic at this time could result in prevention of redd establishment, displacement of fish to less suitable habitats, or creation of poorly-constructed redds (i.e., too shallow to protect eggs adequately).
- Spawning - The female cleans out all loose gravel and fine sediment in a "pit" in preparation for depositing her eggs within a larger area called a "redd." She alternately digs at the redd and settles back into the depression to release eggs. The male accompanies her continuously and releases sperm or "milt" over the newly laid eggs, which settle into spaces between the gravel. The result is a series of egg filled pits within the cleaned redd perimeter that takes approximately 5 days and is a period which the fish expend a tremendous amount of energy. Disturbance of fish during this period by boaters could result in improperly constructed egg pockets, open scattering of eggs, or prevent spawning all together.
- Post-Spawning - The males are no longer attentive while the females remain at the redd for approximately 10 days until they die. The females protect the redds by preventing other fish from digging up their redds and damaging the eggs. Disturbance of fish during this period from boating would result in inadequate post-spawning gravel covering and early mortality of females.
Egg to Fry Development
The average chinook female lays around 4000 eggs. The eggs take around 90 to 150 days to develop before emerging from the gravels as fry, usually in late January or February. Egg development time depends primarily on the water temperature. Cooler water slows egg development while warmer water speeds development.
While the eggs are in the gravel they are very vulnerable to damage and mortality from the effects of trampling or boat grounding on redds. Many of the redds are located next to the river's edge and near gravel bars where boaters may enter and exit the river. Restrictions on wading may be necessary during the egg development.