Uncharted water around Alaska presents an opportunity to increase protected habitat for anadromous fish species. Projects from Trout Unlimited and Alaska Department of Fish and Game aim to document these waters with the state of Alaska to increase protections.

uncharted water

Mark spotting fish on the upstream side of a logjam in a Tongass steelhead stream. Logjams and other large woody debris provide habitat for both juvenile and adult steelhead. © Josh Duplechain

Story by Marian Giannulis

The days of exploring uncharted waters may seem a thing of the past, but across Alaska the effort to find and document fish habitat in previously unlisted waters is ongoing. Alaska’s Anadromous Waters Catalog (AWC) is maintained by the Alaska Department of Fish and Game (ADF&G) and lists the waters with known anadromous fish habitat across the state. Anadromous fish are species that spend portions of their life cycle in both fresh and salt waters and enter fresh water from the sea to spawn, like salmon and steelhead. The AWC lists almost 20,000 water bodies; however, it is believed that it contains only a fraction of the true number of waters with anadromous habitat. This belief is verified each year when new waters are documented and nominated for inclusion in the AWC.

Trout Unlimited’s Fish Habitat Project has worked to expand the fish habitat documented in the AWC since 2018. Mark Hieronymus, TU’s Community Science Coordinator, has led the effort with support from a group of dedicated volunteers. This work has been focused on southeast Alaska’s Tongass National Forest. In southeast Alaska there are over 5,000 anadromous watersheds, but only 346 documented as supporting annual runs of steelhead. Trout Unlimited believes steelhead may use the habitat of twice that many streams, meaning hundreds of streams don’t receive the protections they deserve.

Survey and Data Collection
uncharted water

Sometimes data collection can be a chilly affair. If no steelhead are seen by bank-bound observers, Mark dons his dry suit and checks all the nooks and crannies of the stream for fish. © Sam Roche

The first habitat survey conducted by Trout Unlimited focused on adult steelhead, but since then the effort has expanded to include surveys for juvenile salmon as well. Mark starts his work by reviewing available fisheries and habitat data, then poring over geographic information system (GIS) data and aerial photographs to identify areas not listed in the AWC which are likely to support salmon or steelhead, or both. After he identifies the field-season’s survey areas, Mark works to organize volunteers to support the effort. In southeast Alaska, fish habitat surveys often mean a floatplane ride out to a remote location. It can be a challenge to get volunteers and a good weather window for flying to line up, but when it happens Mark and the team of volunteers are off!

Collecting data on a fish habitat survey can happen several different ways. For juvenile salmon, Mark uses hand nets or minnow traps. For adult steelhead, Mark uses a combination of traditional fishing methods and visual observations from shore. On many surveys he collects data with the chilliest method, which is getting into the stream and snorkeling. One thing that can be counted on for any of these surveys is a substantial amount of bushwhacking. The very obstacles that make these watersheds difficult to move about in—remoteness, challenging terrain, lack of roads, logjams, hip-deep snow—are the same features that make them amazingly productive fish habitat.

Expanding Recognized Fish Habitat

In 2022, Mark successfully documented two steelhead streams. These additions to the AWC represent more than 29,600 feet (5.6 miles) of newly recognized steelhead habitat. After the steelhead surveys in May, juvenile salmon surveys later in the summer led to additions of nearly 11,700 feet of new waters for salmon, as well as the addition of coho salmon to over 30,500 feet (5.8 miles) of listed habitat not previously thought to be used by coho.

Documenting steelhead requires solid evidence of presence, usually in the form of photos showing identifying characteristics of the species. This steelhead was photographed in a north Baranof Island stream that didn’t include steelhead in its AWC listing at the time. © Mark Hieronymus

With the 2022 additions, the running total of new waters and species use in existing waters added to the AWC by Trout Unlimited’s Fish Habitat Project now stands at over 356,000 feet (67.4 miles)! The species added to listed waters include steelhead, cutthroat trout, Dolly Varden char, and pink and coho salmon, and the newly listed waters were all documented with the presence of juvenile coho salmon.

Increased Protections

Getting water bodies listed in the AWC is important, because until these habitats are inventoried and shown to be used by anadromous species, they don’t receive protections under Alaska state law. The protections awarded to fish habitat listed in the AWC help ensure that development in these areas follows guidelines to limit impacts to fish. They include timing windows to limit construction during sensitive migration and spawning periods, and habitat surveys by ADF&G to avoid development around critical habitat areas.

uncharted water

Steelhead in southeast Alaska are fond of logjams and large woody debris, and are often hidden from the bank-bound observer. This fish in a western Baranof Island stream was documented when Mark spotted a single fin sticking out from under the log. © Mark Hieronymus

You don’t have to be a fish biologist to successfully nominate waters to the AWC. Anyone can do it! Trout Unlimited’s Kenai Peninsula Chapter volunteers hosted surveys in the summer of 2021 and 2022 in partnership with the Kenai Watershed Forum. Together, they documented 3.5 miles of newly listed habitat on the Kenai Peninsula.

To nominate new waters, you need to have identified two anadromous fish of the same species in the same water body. Take pictures of the fish with species-identifying characteristics clearly visible. Note the date and time of your observation and record of the geographic coordinates. You can learn more about the process as well as submit your own nominations at adfg.alaska.gov.

As development continues to increase across Alaska, having thorough documentation of fish habitat will become increasingly important to maintaining healthy populations of salmon and steelhead. To learn more or get involved, follow Trout Unlimited Alaska on Facebook or Instagram, or visit americansalmonforest.org.

Trout Unlimited’s mission is to protect, reconnect and restore North America’s coldwater fisheries and their watersheds. Marian Giannulis is the Alaska Communications & Engagement Director for Trout Unlimited.

For more conservation minded content check out Fish Alaska’s entire Conservation Blog.