Arctic terns, © Jim Maloney

Chugach National Forest: Shaped by Rock, Ice and the Ocean

Claire Colegrove, Alaska Representative

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When picturing our national forests, it is most common to think of endless expanses of trees and other vegetation dotted by lakes, rivers and staggering mountain peaks. We picture iconic North American wildlife like bears and deer inhabiting these expanses. The Chugach National Forest is a stark contrast to this more familiar image. The Chugach is the northernmost coastal forest – over a third of its nearly 7 million acres is made up of rock and ice. Visitors coming to this area expect to see salmon, orca and a wide variety of sea and shorebirds. A majority of the Chugach’s 500,000 annual visitors are heading to the Kenai Peninsula, the Copper River Delta or Prince William Sound, all places known for their coastal and marine recreation opportunities. This is a forest with strong ties to ice and the ocean, both for its dominant ecosystems and for human use.

In the spring of 2012, the United States Forest Service released their new planning regulations in accordance with the National Forest Management Act. This new planning rule represented a significant shift in federal forest policy. Most important to Defenders is the Service’s new approach to managing for biodiversity: they plan to look at the entire ecosystem as a whole. The Service’s new planning rule uses what is called a “coarse filter” method, which examines the overall ecosystem integrity. Ecosystem integrity is essential if you want to maintain a healthy and diverse population of plants and animals in a forest like the Chugach, especially in light of the continuing impacts of a changing climate.

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Sea lions in Prince William Sound, © Flickr/J. Stephen Conn

The Forest Service selected eight “early adopter” forests throughout the country to lead the way, and the Chugach National Forest is one of them. Though the Chugach is equal in size to the state of New Hampshire, it has only 90 miles of Forest Service roads. The Chugach National Forest is commonly referred to as a “custodial forest” meaning the Forest Service’s management of it is largely for recreation and conservation purposes rather than timber harvest.

The management plan is executed in three phases: assessment, revision and monitoring. The Chugach Forest Service staff is currently in their assessment phase, collecting and examining the best available information on the current forest condition and how the forest is used. Next, they will revise their management plan over the next two years, and then set up a monitoring process to study how effective the new management practices are.

In the first phase, Defenders is working with the Service to determine how vulnerable the forest is to climate change, which will help determine the Service’s long-term plans for addressing it. We are trying to identify what areas of the forest will be most impacted by climate change, and what those impacts will look like both for the forest’s plant and animals species, and for the people who rely on them. This is called a climate vulnerability assessment. I will be leading the climate vulnerability assessment chapter examining the effects of climate change on the coasts and seascapes.

Short-billed dowhitcher, one of many species that rely on the tidal flats in Chugach NF  © Flickr/Melissa Gabrielson, USFWS

Short-billed dowhitcher, one of many species that rely on the tidal flats in Chugach NF © Flickr/Melissa Gabrielson, USFWS

In a coastal forest like the Chugach, there are a lot of ways climate change can affect the ecosystem, including sea level rise, glaciers and snow and ice melt, habitat composition changes and ocean acidification. All these factors have the potential to greatly impact habitat and wildlife survival, as well as human use of the forest. Sea level rise can increase habitat for some species and diminish it for others. Low-lying tidal flats along the Chugach comprise important nesting habitat for a large number of shore and seabirds, which means that even slight sea level shifts could have vast impacts on these species. As glaciers melt, they alter the composition of and access to the land. For example when a glacier melts, it not only exposes habitat previously covered by snow and ice, but it also causes the terrain that was compressed to rebound or rise up, which diminishes the effects of subsequent sea level rise. Ocean acidification can inhibit the ability of creatures like mollusks to form shells, which diminishes food for larger species (click here for more on this climate change impact). These are just a few examples of the many changes occurring in the Chugach that require us to put in place the best possible forward-thinking management practices and monitoring procedures so that we can know how wildlife in the Chugach is being affected, and what might be done to help them adapt.

The Forest Service is slated to complete their assessment phase late this summer. Once that is complete, they will begin a two-year plan revision process to update their 2002 management plan. We are looking forward to working with the Forest Service throughout this process to ensure the Chugach remains a thriving habitat for wildlife.