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Quantitative models, including Ecopath, take food web studies to a higher level of analysis

The Ecopath model, designed to describe the flow of energy through a food web, as evolved since it was first developed in the early 1980s in Hawaii. This article is part of a series focused on different models and their uses within the Puget Sound ecosystem.

Prey and predators create varying life-or-death conditions for salmon, as shown with Atlantis model

The three-dimensional Atlantis model can represent physical, chemical and biological processes and can incorporate direct human involvement, such as fisheries management, habitat improvements and economic outcomes. It has been used to study the food web to determine whether salmon in Puget Sound are more threatened by predators or by the lack of a stable food supply and to evaluate specific

Puget Sound's Grand Uncertainties Matrix

Researchers are compiling a strategic list of scientific uncertainties related to Puget Sound recovery. The list will be used to prioritize future funding and research to address critical knowledge gaps about the ecosystem.

Impacts of low oxygen on Puget Sound aquatic life (infographic)

Chronic stress from lack of oxygen can make aquatic organisms more vulnerable to disease, pollution, or predation. Low oxygen can also result in reduced habitat for some species. Aquatic species may escape, acclimate, adapt, or die with exposure.

Circulation in Puget Sound (infographic)

Estuaries around the world including Puget Sound perform an amazing feat of continuous water mixing called estuarine exchange flow. 

Sources of nitrogen in Puget Sound (infographic)

Nitrogen is a chemical element that is essential for the growth of all life on earth. But too much nitrogen can lead to low dissolved oxygen and other problems such as toxic algal blooms that can harm or kill aquatic organisms. 

Hypoxia (fact sheet)

The following fact sheet provides an overview of low oxygen conditions in Puget Sound. It addresses some of the related causes and concerns that have been identified by scientists in the region. The overview was prepared in conjunction with a series of workshops on hypoxia and nutrient pollution presented by the University of Washington Puget Sound Institute. 

Phytoplankton and primary productivity (fact sheet)

In many parts of Puget Sound, hypoxic waters are thought to be at least in part due to overgrowth of microscopic algae, which is triggered by excess nitrogen. That means it’s important to understand the dynamics of primary productivity – the rate at which those microscopic algae, known as phytoplankton, produce organic matter through photosynthesis and in this way provide the base of the food web

The role of sediment in nitrogen cycling and hypoxia (fact sheet)

How do marine sediments affect oxygen and nutrient levels in the water?

Nitrogen and phosphorus enter marine sediments either by diffusion from the water column or as part of organic particles that settle on the surface. Once nitrogen is in the sediment it can either be buried, be converted to nitrogen gas by bacteria (a process known as denitrification) or re-enter the water column. Similarly

Legal milestones for Indigenous sovereignty and salmon co-management in the Puget Sound region

Treaty rights are critical to the sovereignity of Puget Sound area Tribes and are deeply connected to natural resource management. Five landmark treaties in our region were signed during a three-year period from 1854 to 1856 and continue to drive policy to this day.