Systems Dead Zones

Dead Zones – low concentrations of dissolved oxygen = hypoxia Dead Zones – low concentrations of dissolved oxygen = hypoxia below 5 ppm movement slows, below 5 ppm movement slows, below 2 ppm organisms that can will leave, below 2 ppm organisms that can will leave, below 0.2 ppm black sediments with anerobic bacteria. below 0.2 ppm black sediments with anerobic bacteria. Examples: Lousiana coast, Hood Canal, San Diego/Mexico area Examples: Lousiana coast, Hood Canal, San Diego/Mexico area

Hood Canal Spring of 2002 and again in the fall of 2003, thousands of dead fish and other marine life washed up on Hood Canal beaches, having basically suffocated Spring of 2002 and again in the fall of 2003, thousands of dead fish and other marine life washed up on Hood Canal beaches, having basically suffocated Puget Sound Action Team

More Detail juvenile perch (June 2003) juvenile perch (June 2003) numerous fish, octopi and sea cucumbers (fall 2002 and 2003) numerous fish, octopi and sea cucumbers (fall 2002 and 2003) Hood Canal’s dissolved oxygen (DO) concentrations are at their lowest as compared to data from the 1950s, 60s, and 90s. Hood Canal’s dissolved oxygen (DO) concentrations are at their lowest as compared to data from the 1950s, 60s, and 90s.

1950 – 2004 DO data

The Problem Many natural factors may contribute to the low dissolved oxygen problem: Many natural factors may contribute to the low dissolved oxygen problem: slow water circulation and mixing, slow water circulation and mixing, the incoming ocean water quality, the incoming ocean water quality, changes in the weather, changes in the weather, high growth of algae, high growth of algae, loadings of carbon and nitrogen, and loadings of carbon and nitrogen, and changes in the native marine life composition. changes in the native marine life composition.

The Problem People may be affecting the dissolved oxygen concentration in several ways, including People may be affecting the dissolved oxygen concentration in several ways, including altering the river flows, landscapes, altering the river flows, landscapes, and altering the marine life, and altering the marine life, adding excess nutrients to the waters that can fuel extra algae growth, adding extra carbon to the ecosystem, adding excess nutrients to the waters that can fuel extra algae growth, adding extra carbon to the ecosystem, and influencing climate change. and influencing climate change.

Overgrowth due to increased nutrients July 14th 2005, people started noticing red streaks on the waters of the western shore of Hood Canal. By the weekend, it had grown to extensive patches between Potlatch and Hoodsport, north to Lilliwaup. It looked like tomato soup floating on top of the water. The cause of this coloration is an organism called Noctiluca (single cell algae) CAN CAUSE OXYGEN DEPLETION July 14th 2005, people started noticing red streaks on the waters of the western shore of Hood Canal. By the weekend, it had grown to extensive patches between Potlatch and Hoodsport, north to Lilliwaup. It looked like tomato soup floating on top of the water. The cause of this coloration is an organism called Noctiluca (single cell algae) CAN CAUSE OXYGEN DEPLETION

Marine Systems – Wind Driven Fish Kills Wind over the Canal is an important driver of surface currents. Wind over the Canal is an important driver of surface currents. On average, the surface layer of the Canal is moving northward and outward carrying fresh water from rivers towards the ocean. On average, the surface layer of the Canal is moving northward and outward carrying fresh water from rivers towards the ocean. A northerly wind can cause a temporary reversal the surface current, while a southerly wind accelerates the northward current. A northerly wind can cause a temporary reversal the surface current, while a southerly wind accelerates the northward current. Such movements can cause the surface layer to evacuate certain parts of the canal, and its place is filled by water upwelling from the depth. Such movements can cause the surface layer to evacuate certain parts of the canal, and its place is filled by water upwelling from the depth. Upwelled water is also low in oxygen, wind-driven upwelling is an important possible mechanism triggering fish kill events Upwelled water is also low in oxygen, wind-driven upwelling is an important possible mechanism triggering fish kill events

Land Use Pale orange = crops Pale orange = crops Purple= people Purple= people Green= Green=forest

Solving It Using the information from Chapter 2 on policy and economics what do you suggest be done? Using the information from Chapter 2 on policy and economics what do you suggest be done?

Solving It Will take time Will take time  Twenty-eight entities, including  local, state and federal agencies,  tribal governments,  non–profit organizations and  universities,  have come together to form the Hood Canal Low Dissolved Oxygen Program (HCDOP).  have come together to form the Hood Canal Low Dissolved Oxygen Program (HCDOP).  The goal of the HCDOP is to determine the sources of the low dissolved oxygen in Hood Canal, the effect on marine life, and to work with local, state, federal, and tribal government policy makers to develop potential corrective actions that will help restore and maintain a level of dissolved oxygen that will not stress the marine life.  The goal of the HCDOP is to determine the sources of the low dissolved oxygen in Hood Canal, the effect on marine life, and to work with local, state, federal, and tribal government policy makers to develop potential corrective actions that will help restore and maintain a level of dissolved oxygen that will not stress the marine life.

Systems - Organizational Corrective Action and Education group focuses on preliminary assessment, corrective actions and demonstration projects that will help to improve levels of dissolved oxygen in Hood Canal. This group educates and involves residents in ways they can help improve the quality of water the Canal. Corrective Action and Education group focuses on preliminary assessment, corrective actions and demonstration projects that will help to improve levels of dissolved oxygen in Hood Canal. This group educates and involves residents in ways they can help improve the quality of water the Canal. IAM is a three-year study to use marine, freshwater and biota monitoring data and a computer model to quantify the role the various natural processes and human actions are playing to control the concentrations of dissolved oxygen in Hood Canal and test corrective action scenarios. IAM is a three-year study to use marine, freshwater and biota monitoring data and a computer model to quantify the role the various natural processes and human actions are playing to control the concentrations of dissolved oxygen in Hood Canal and test corrective action scenarios. Hood Canal Dissolved Oxygen Program

Model Model will evaluate the effects of changes in inputs into the Canal, Model will evaluate the effects of changes in inputs into the Canal, such as different ocean conditions, such as different ocean conditions, elimination of septic inputs, elimination of septic inputs, changes in the Skokomish River flow, changes in the Skokomish River flow, or replacement of riparian alder trees with cedar, on the system. or replacement of riparian alder trees with cedar, on the system. Evaluate potential corrective actions for the low dissolved oxygen condition.

Geologic Mapping Mapping in this area is to address growing social issues associated with rapid suburban development. Mapping in this area is to address growing social issues associated with rapid suburban development. The unconsolidated sediments in the area are a source for aquifers that provide drinking water to many residents. The unconsolidated sediments in the area are a source for aquifers that provide drinking water to many residents. Nature and extent of deposits in the area, to assess the long-term availability and potential contamination problems with the local groundwater resources. Nature and extent of deposits in the area, to assess the long-term availability and potential contamination problems with the local groundwater resources.

Marine Life Study effects on benthic organisms (critters living on and within the sea bed). Study effects on benthic organisms (critters living on and within the sea bed). assess the effects of hypoxia on these benthic communities assess the effects of hypoxia on these benthic communities Benthic organisms don’t move around a great deal - immobile Benthic organisms don’t move around a great deal - immobile STUDY how community structure varies in space and time in Hood Canal which species are most important in determining benthic community variation the relative importance of dissolved oxygen concentration in overlying water, water depth, sediment organic-carbon concentration, and other potentially important environmental variables in determining variation on benthic community structure the statistical significance (by random permutation analysis) of observed relationships between oxygen concentration and benthic community structure

Benthic Species with Resistance to Hypoxia

Hood Canal Food Chains OPEN WATER SYSTEM OPEN WATER SYSTEM Tertiary Consumer - Orca Tertiary Consumer - Orca Secondary Consumer - Salmon (chinook high in PCB) Seals, sea lions Secondary Consumer - Salmon (chinook high in PCB) Seals, sea lions Primary Consumer – forage fish (herring, surf smelt) Primary Consumer – forage fish (herring, surf smelt) Producer - phytoplankton Producer - phytoplankton D E C O M P O S E R S D E C O M P O S E R S INTERTIDAL SYSTEM INTERTIDAL SYSTEM Secondary Consumer – harbor seal, sea lion, gulls Secondary Consumer – harbor seal, sea lion, gulls Primary Consumer – amphipods (eat detritus), sea stars, urchin, mussel, barnacle, perch Primary Consumer – amphipods (eat detritus), sea stars, urchin, mussel, barnacle, perch Producer – Benthic microalgae, eelgrass, seaweed Producer – Benthic microalgae, eelgrass, seaweed

How Does excess Nitrogen cause a dead zone? 1. Coastal waters are swamped with nutrients, particularly nitrogen, from sewage or fertilizer. 2. Excess nitrogen allows algae populations to grow very large. 3. Dead algae in turn feed bacteria and their populations grow. 4. Bacteria use up most of the oxygen in the water. 5. Shellfish suffocate, and fish must swim for more healthful waters.

Resources Text Chapter 3 Text Chapter 3 anal_news/hc_news_online.htm anal_news/hc_news_online.htm