Oh What a Tangled Web: Ecosystem-Based Management

Part B: Integrated Ecosystem Assessments

EBFM is a particularly promising approach for the improvement of commercial fisheries management. A more thorough understanding of the complexities of the ecosystem in which exploited or depleted fish species live can help researchers better predict the effects of the ecosystem on fishing and the effects of fishing on the ecosystem. When managing a commercial fishery, ecosystem complexities are compounded by economic complexities and the need to sustain a profitable business as well as a healthy ecosystem.

Integrated Ecosystem Assessment programs (IEAs) are used to support effective EBFMs within NOAA Fisheries. Using an integrated science approach, IEAs aim to balance the needs of nature and society today and into the future while also supporting diverse marine resource management objectives in an ecosystem context. IEAs provide a way to assess ecosystem status relative to objectives of different groups (e.g., fishing, recreation, energy production, shipping, agriculture, forestry, food, clean water), account for the holistic impact of management decisions, and guide management evaluations. IEAs consist of analyses that help resource managers make more informed and effective management decisions. For example, IEAs contain:

  • Assessments of status and trends of the ecosystem condition, including ecosystem services.
  • Assessments of activities or elements in an ecosystem that can stress it.
  • Prediction of the future condition of the ecosystem under stress if no management action is taken.
  • Prediction of the future condition of the stressed ecosystem under different management scenarios, and evaluation of the success of management actions in achieving the desired target conditions.

1. Watch this short introductory video about IEAs.

What is an IEA? If video does not play, visit Monterey Bay's EBM page.


2. Learn about each step of the IEA:

Step 1: Define the System and the Goals

Defining goals provides focus and a measure for progress. In order to achieve those goals, it is key to understand the place and context, or ecosystem (including inter-related system components). A tool for understanding the ecosystem is a Conceptual Model.


Steps 2 & 3: Select Indicators & Assess Ecosystem

Indicators capture the status and trends of key ecosystem components defined in Step 1. They should represent status and trends of individual components but collectively reflect the condition and trajectory of the socio-ecological system when considering the whole ecosystem.


Step 4: Assess Risk

By conducting a risk assessment, it is possible to determine the probability of undesirable events occurring to ecosystem components identified in Step 1. Risk is generally described by the sensitivity and/or resilience of a given ecosystem component (measured by indicators) to various natural and human pressures and changes that result in change to the ecosystem.


Step 5: Evaluate Management Strategies

Building off information from the previous steps, evaluation management strategies considers potential outcomes of alternative management actions on ecosystem components (natural and human) and identifies trade-offs within management objectives. These evaluations inform managers which strategies could be the most useful in achieving their objectives.

The ocean off the west coast of Hawai'i Island is very important for biodiversity and human society. This part of the ocean includes the largest Hawaiian expanse of intact coral reef. The ecosystem is vulnerable to many pressures: increasing population, coastal development, fishing, pollution, and climate change. Five different management strategies were evaluated by measuring their impact on three ecosystem services. Pressures including fishing, land-based pollution, climate change, and coral bleaching were incorporated.

3. Visit An Evaluation of Management Strategies West Hawai'i Project to read about Hawai'i Island's evaluation of management strategies.

Checking In

Answer the following questions to check your understanding of information presented in the Evaluation of Management Strategies West Hawai'i Project

  • What were some of the indicators in the West Hawai'i Island marine ecosystem?
  • What was likely to happen if no changes were made based on the evaluation?

After an Evaluation of Management Strategies

After a Management Strategy Evaluation, one of the suggested actions is selected and implemented. Indicators continue to be monitored as it's important to learn if the action has been successful or not. If the action has been successful, the status, trends, and risk to the indicators continue to be analyzed regularly for change. If the action has not been successful, the outcomes are assessed and evaluated to refine goals and targets or indicators in order to achieve the original objectives.

Stop and Think

4: In your own words, explain how using Integrated Ecosystem Assessments can help to support fisheries using EBFM.

Optional Extensions

Understanding EBFM

About IEA

Challenge of Change – EBM

Indicators of Climate Change in California Report, May 2018

Studying marine biodiversity from pole to pole