SystemsSystems

Dead ZonesDead Zones

Dead ZonesDead Zones

Dead Zones – low concentrations of Dead Zones – low concentrations of dissolved oxygen = hypoxiadissolved oxygen = hypoxiabelow 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 below 0.2 ppm black sediments with anerobic

bacteria. bacteria. Examples: Lousiana coast, Hood Canal, Examples: Lousiana coast, Hood Canal,

San Diego/Mexico areaSan Diego/Mexico area

Hood CanalHood Canal

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

Puget Sound Action Team

More DetailMore Detail

juvenile perch (June 2003) juvenile perch (June 2003) numerous fish, octopi and sea cucumbers numerous fish, octopi and sea cucumbers

(fall 2002 and 2003) (fall 2002 and 2003)

Hood Canal’s dissolved oxygen (DO) Hood Canal’s dissolved oxygen (DO) concentrations are at their lowest as concentrations are at their lowest as compared to data from the 1950s, 60s, compared to data from the 1950s, 60s, and 90s. and 90s.

1950 – 2004 DO data1950 – 2004 DO data

The ProblemThe Problem

Many natural factors may contribute to the low Many natural factors may contribute to the low dissolved oxygen problem: 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 ProblemThe Problem

People may be affecting the dissolved People may be affecting the dissolved oxygen concentration in several ways, oxygen concentration in several ways, including 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 adding excess nutrients to the waters that

can fuel extra algae growth, adding extra can fuel extra algae growth, adding extra carbon to the ecosystem, carbon to the ecosystem,

and influencing climate change.  and influencing climate change. 

Overgrowth due to increased Overgrowth due to increased nutrientsnutrients

July 14th 2005, people July 14th 2005, people started noticing red started noticing red streaks on the waters of streaks on the waters of the western shore of the western shore of Hood Canal. By the Hood Canal. By the weekend, it had grown to weekend, it had grown to extensive patches extensive patches between Potlatch and between Potlatch and Hoodsport, north to Hoodsport, north to Lilliwaup. It looked like Lilliwaup. It looked like tomato soup floating on tomato soup floating on top of the water.top of the water.

The cause of this The cause of this coloration is an organism coloration is an organism called called Noctiluca Noctiluca (single (single cell algae) CAN CAUSE cell algae) CAN CAUSE OXYGEN DEPLETIONOXYGEN DEPLETION

Marine Systems – Wind Driven Marine Systems – Wind Driven Fish KillsFish Kills

Wind over the Canal is an important driver of Wind over the Canal is an important driver of surface currents. surface currents. On average, the surface layer of the Canal is moving On average, the surface layer of the Canal is moving

northward and outward carrying fresh water from northward and outward carrying fresh water from rivers towards the ocean.rivers towards the ocean.

A northerly wind can cause a temporary reversal the A northerly wind can cause a temporary reversal the surface current, while a southerly wind accelerates surface current, while a southerly wind accelerates the northward current. the northward current.

Such movements can cause the surface layer to Such movements can cause the surface layer to evacuate certain parts of the canal, and its place is evacuate certain parts of the canal, and its place is filled by water upwelling from the depth. filled by water upwelling from the depth.

Upwelled water is also low in oxygen, wind-driven upwelling Upwelled water is also low in oxygen, wind-driven upwelling is an important possible mechanism triggering fish kill events is an important possible mechanism triggering fish kill events

Land UseLand UsePale Pale

orange = orange = cropscrops

Purple= Purple= peoplepeople

Green=Green=

forestforest

Solving ItSolving It

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

Solving ItSolving It Will take timeWill take time Twenty-eight entities, including Twenty-eight entities, including

local, state and federal agencies, local, state and federal agencies, tribal governments, tribal governments, non–profit organizations and non–profit organizations and universities, universities,

have come together to form the Hood Canal Low Dissolved Oxygen have come together to form the Hood Canal Low Dissolved Oxygen Program (HCDOP).  Program (HCDOP). 

The goal of the HCDOP is to determine the sources of the low 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 dissolved oxygen in Hood Canal, the effect on marine life, and to work with local, state, federal, and tribal government policy makers work with local, state, federal, and tribal government policy makers to develop potential corrective actions that will help restore and to develop potential corrective actions that will help restore and maintain a level of dissolved oxygen that will not stress the marine maintain a level of dissolved oxygen that will not stress the marine life.  life. 

Systems - OrganizationalSystems - Organizational

Corrective Action and Education Corrective Action and Education group focuses on preliminary group focuses on preliminary assessment, corrective actions assessment, corrective actions and demonstration projects that and demonstration projects that will help to improve levels of will help to improve levels of dissolved oxygen in Hood Canal.  dissolved oxygen in Hood Canal.  This group educates and involves This group educates and involves residents in ways they can help residents in ways they can help improve the quality of water the improve the quality of water the Canal.  Canal. 

IAM is a three-year study to use IAM is a three-year study to use marine, freshwater and biota marine, freshwater and biota monitoring data and a computer monitoring data and a computer model to quantify the role the model to quantify the role the various natural processes and various natural processes and human actions are playing to human actions are playing to control the concentrations of control the concentrations of dissolved oxygen in Hood Canal dissolved oxygen in Hood Canal and test corrective action and test corrective action scenarios. scenarios.

Hood Canal Dissolved Oxygen Program

ModelModel Model will evaluate the effects Model will evaluate the effects

of changes in inputs into the of changes in inputs into the Canal, Canal, such as different ocean conditions, such as different ocean conditions, elimination of septic inputs, elimination of septic inputs, changes in the Skokomish River changes in the Skokomish River

flow, flow, or replacement of riparian alder or replacement of riparian alder

trees with cedar, on the system. trees with cedar, on the system. Evaluate potential corrective actions Evaluate potential corrective actions

for the low dissolved oxygen for the low dissolved oxygen condition. condition.

Geologic MappingGeologic Mapping Mapping in this area is to Mapping in this area is to

address growing social issues address growing social issues associated with rapid suburban associated with rapid suburban development. development.

The unconsolidated sediments in The unconsolidated sediments in the area are a source for the area are a source for aquifers that provide drinking aquifers that provide drinking water to many residents. water to many residents.

Nature and extent of deposits in Nature and extent of deposits in the area, to assess the long-term the area, to assess the long-term availability and potential availability and potential contamination problems with the contamination problems with the local groundwater resources. local groundwater resources.

Marine LifeMarine Life Study effects on benthic organisms (critters living on and within the Study effects on benthic organisms (critters living on and within the

sea bed).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 - immobileBenthic 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 Benthic Species with Resistance to HypoxiaHypoxia

Hood Canal Food ChainsHood Canal Food Chains OPEN WATER SYSTEMOPEN WATER SYSTEM Tertiary Consumer - Tertiary Consumer - OrcaOrca

Secondary Consumer - Secondary Consumer - Salmon (chinook high in Salmon (chinook high in PCB) Seals, sea lionsPCB) Seals, sea lions

Primary Consumer – Primary Consumer – forage fish (herring, surf forage fish (herring, surf smelt)smelt)

Producer - phytoplanktonProducer - phytoplankton

DDEECCOOMMPPOOSSEERRSS

INTERTIDAL SYSTEMINTERTIDAL SYSTEM

Secondary Consumer – Secondary Consumer – harbor seal, sea lion, gullsharbor seal, sea lion, gulls

Primary Consumer – Primary Consumer – amphipods (eat detritus), amphipods (eat detritus), sea stars, urchin, mussel, sea stars, urchin, mussel, barnacle, perchbarnacle, perch

Producer – Benthic Producer – Benthic microalgae, eelgrass, microalgae, eelgrass, seaweedseaweed

How Does excess Nitrogen cause a How Does excess Nitrogen cause a dead zone?dead zone?

1.1. Coastal waters are swamped with nutrients, Coastal waters are swamped with nutrients, particularly nitrogen, from sewage or fertilizer. particularly nitrogen, from sewage or fertilizer.

2.2. Excess nitrogen allows algae populations to Excess nitrogen allows algae populations to grow very large. grow very large.

3.3. Dead algae in turn feed bacteria and their Dead algae in turn feed bacteria and their populations grow.populations grow.

4.4. Bacteria use up most of the oxygen in the Bacteria use up most of the oxygen in the water. water.

5.5. Shellfish suffocate, and fish must swim for Shellfish suffocate, and fish must swim for more healthful waters. more healthful waters.

ResourcesResources

Text Chapter 3Text Chapter 3http://www.psat.wa.gov/Publications/http://www.psat.wa.gov/Publications/

hoodcanal_news/hc_news_online.htmhoodcanal_news/hc_news_online.htm