DECLINE OF SKOKOMISH NATION SPOT SHRIMP CATCH IN LOW DISSOLVED OXYGEN WATERS OF THE HOOD CANAL,PUGET SOUND,STATE OF WASHINGTON

This study examined the hypothesis that the Student Researcher: Ho-Wan-Ut Peterson; decreasing number of spot shrimp caught by Mentor: Lalena Amiotte; Skokomish Nation, Washington the Skokomish tribal fishers was related to the areas of documented decreasing dissolved oxygen levels within the treaty fishing area of 4 the Skokomish Indian Nation (Hood Canal). INTRODUCTION gram dissolved oxygen data were Dissolved oxygen levels recorded and sampled compiled for the same three transects by state, citizen and tribal entities were We hypothesized that the amount of at the bottom depths of the Hood Canal compiled into a database. The recorded treaty-caught spot shrimp by the Sko- and the same months. Both sets of data dissolved oxygen levels were then sorted into were graphed and compared. catch areas set by the Washington State komish Nation fishers has declined Department of Fish and Wildlife. Catch since 2001, possibly as a result of volume was then compared to areas of low decreasing dissolved oxygen levels in dissolved oxygen. Results show that since the the southern regions of the Hood RESULTS summer of 2001, tribal treaty catch of spot Canal. Aquatic life needs 5–20 parts shrimp has declined significantly in the lower portion of the Hood Canal (Anna’s Bay), where per million (ppm) oxygen for sustain- Skokomish tribal catch datasets the dissolved oxygen levels have been steadily ability; ,5 ppm causes biological stress, point to lower shrimp catch in docu- decreasing. and ,3 ppm kills fish. Low dissolved mented areas of low dissolved oxygen oxygen levels have been hypothesized to within the Hood Canal; however, be caused by failing septic tank systems further research is needed. The low along the Hood Canal’s waterfront, dissolved oxygen phenomenon appears agricultural waste, current forest man- to be most extreme in the lower end of agement practices, algae blooms, storm 1 the Hood Canal (Anna’s Bay and Lynch water runoff, and salmon carcasses. Cove) during the summer months. The Oxygen depletion in the Hood Canal middle section of the Hood Canal occurs as products rich in nitrogen (north of Potlatch) has dissolved oxygen (septic waste for example) decompose levels that generally provide adequate depleting oxygen. oxygen for marine life; although in the Spot shrimp are a traditional food of summer months, some areas are at levels the Skokomish people. Spot shrimp are that could pose biological stress. The high in tryptophan; selenium; protein; northern end of the Hood Canal (north vitamins D, B12, and B3; iron; phos- of the Hamma Hamma River) is the phorus; omega 2 fatty acids; zinc; only area in the Hood Canal that copper; and magnesium.2 During the dissolved oxygen is adequate year round catch season, shrimp are a staple food of for aquatic life. From the dissolved the Skokomish people. Spot shrimp are oxygen and shrimp data sets, Skokom- also an economic resource for the tribe. ish fishers are advised to set their shrimp pots in the northern regions of their treaty waters to ensure substantial catch MATERIALS AND METHODS numbers.

The tribal spot shrimp catch data- REFERENCES base was compiled for April, May, June, 1. Puget Sound Action Team. Preliminary actions and July of 2004. April and June were and corrective assessment plan on Hood Canal. 3 compiled from 2005. From these data, 2003. Available at: http://www.psat.wa.gov/ three transects were identified in the Publications/PACA_html/paca_ex_summary.htm. Hood Canal. Shrimp are bottom dwell- 2. Shrimp nutritional analysis. 2004. Available at: ers, so for this study only dissolved http://www.sensiblenutrition.com/_shrimp. oxygen data from the bottom sample 3. Skokomish Nation Fisheries. Spot Shrimp Catch Database. April 2001–July 2005. depths were entered into the database. 4. Hood Canal dissolved oxygen program data- Washington State Department of Ecol- base. EKO-system database management. 2005. ogy and the Citizen Monitoring Pro- Available at: http://hoodcanal.eko-system.us.

Ethnicity & Disease, Volume 16, Autumn 2006 S5-17