Southwest Alaska: Kodiak and the Aleutian Islands

“We were intrigued by the abrupt termination of Nereocystis luetkeana east of Samalga Pass and the exuberant expression of growth and reproduction in this population on the margin of this species’ geographic range.”

Kathy Ann Miller, 1989

Southwest Alaska can be split into three regions: Kodiak and Afognak Islands across the Shelikof Strait from Katmai National Park, the Eastern Aleutian Islands and the Western Aleutian Islands, including Amchitka.

A Tapestry of Kelp Textures

Nasquluq is the Alutiiq word for bull kelp. It comes from the word head. The bull kelp in Alutiiq territory, from Prince William Sound into Cook Inlet and around the Kodiak Archipelago is robust and healthy and has been used for centuries as navigational aid, indicating rocky outcrops and shallower waters, as fishing line made from the long, singular stipe, and as fertilizer, creating soil for potato beds in the post-contact coastal villages of Native and Russian-descended peoples. Generally, seaweeds in Alaska are large and leafy, supercharged by the cold waters. In SW Alaska, there is holey Agarum, golden Alaria, and cabbage-like Costaria, making a three-dimensional tapestry of textures, creating habitat and food source for countless organisms. The 1913 kelp surveys of Western Alaska list Eualaria fistulosa, or dragon kelp as it is called locally, averaging 40 feet long. Dim photographs show blades that would fill entire rooms in length and width. Giant kelp, or Macrocystis pyrifera, is working its way into the kelp play group, becoming more common in the fjords and bays of Kodiak and Afognak with every passing season. Kodiak is the terminus of the giant kelp’s range (although the 1913 report claims it did not exist north of Sitka Sound at that time), but bull kelp, while arriving at the surface later in the year than farther south, makes up the historic kelp beds and extends westward to Umnak Island almost at the bottom of the upfacing crescent of the Aleutian chain of islands. 


The wrack at Afognak Island, 2021
Photo by Josie Iselin

The wrack at Afognak Island, 2021: Agarum, Alaria, Nereocystis, Costaria and Macrocystis.

Photo by Josie Iselin

In 1987, Kathy Ann Miller and Jim Estes found this terminal fixed bed of bull kelp and went diving in it. It was full of mature kelps with reproductive sori patches and plenty of long, epiphytic nori (Pyropia nereocystis) indicating persistence of more than the typical year of growth. The understory was rich with sponges, barnacles, other kelp, and plenty of Pycnopodia helianthoides or sunflower sea stars. The divers’ amazement at the plethora of life created by this robust bull kelp forest at the outer edge of its biogeography comes through loud and clear. Their questions as to why the bull kelp ends in that particular spot have not clearly been answered. (Miller et al, Botanica Marina, 1989). Brenda Konar and others have surveyed the near shore benthic communities at Samalga Pass just west of Umnak and confirm that  bull kelp and sunflower sea stars continue to be found to the east of this point, but not to the west, creating a biogeographic divide, or break, here at the end of the bull kelps range.

Sea Otter and Sunflower Sea Star: Are They Here?

Yes, there are sea otters, but…it’s complicated.

Around Kodiak Island, the northern sea otter population is healthy, has held steady for decades, and bull kelp is abundant. A bit to the west, the Aleutian Islands is where the clear relationship between the kelp forest and the sea otter was first revealed to the broader world community beyond the Alutiiq peoples of Southwestern Alaska. The mostly unpopulated islands provided a natural experiment that illustrated sea otters’ top-down control over sea urchins, thereby affecting kelp and algal distributions. In 1972, when Jim Estes, a budding PhD student, went scuba diving at Amchitka and other nearby islands where otters were common, the kelp was abundant, but when he went diving at Attu Island, with no sea otters, there was little kelp and a sea floor covered with urchin. He wrote up his findings in a paper in 1974, describing the kelp-urchin-sea otter trophic cascade, suggesting sea otters as the primary cause of the differences in the marine communities. When sea otters were present, they ate urchins, which feed on kelp, allowing the kelp forest to thrive. When otters were absent, the urchin populations grew and devastated kelp forests. The sea otter, wrote Estes and co-author John Palmisano, is “an evolutionary component essential to the integrity and stability of the ecosystem.”

Continued sea otter population recovery in the Aleutian Islands took a left turn, however,  in the 1990s, when many sea otter populations suddenly crashed, declining by up to 90%, and kelp habitat around those islands reverted to urchin barren. It is suggested that sea otters have become prey, like seals and sea lions, for killer whales. The orca's preferred prey, whale calves, had disappeared post-World War II, when industrial whaling in the North Pacific removed almost all of the humpback, gray, sperm and other great whales. In his book Serendipity, Jim Estes lists the destruction: In just an eight year period from 1963–1971, 92,403 whales were killed throughout the south-central Bering Sea and North Pacific Ocean. This wholesale removal of a food source for orcas has repercussions today. Otter numbers are low in the western Aleutians, listed at around 2,400 otter in a January 2023 report by Alaska Fish and Game. Their numbers are not rising and kelp habitat in the Western Aleutians has not recovered.

Yes. There are sunflower sea stars here in Southwest Alaska.

While their numbers are reduced, the Pycnopodia populations in the northernmost waters of the North Pacific were not as completely devastated  by the sea star wasting disease as farther south. Before 2013, Alaska Department of Fish and Game did not think of conducting sunflower sea star surveys—they were too ubiquitous. Now, counting and measuring arm length of the Pycnopodia bycatch that come up during crab surveys is important for tracking the health of the population.

The Great Volcanic Eruption of 1912

A field of floating pumice from Katmai volcano August, 1912: Amalik Bay from north end of Takli Island. The boat has been forced as far into the field of pumice as its occupant can drive it.

Photo by George C Martin

Novarupta erupted in what would become Katmai National Park, on June 6, 1912 covering everything around Kodiak, 100 miles away, with ash and then pumice. For three days the village was immobilized by darkness, falling ash and toxic gases. The wildlife, both marine and on land, was devastated: bears were blinded, salmon, in all stages of life, perished, birds fell from the sky. The ocean was covered in ash, and then in great floats of pumice that persisted for over a year. The bull kelp of that season would have been starved of light and at the surface, abraded by pumice. The rocky substrate it depends on was covered in ash and sediment from the many landslides that occurred. It was reported by George C. Martin in National Geographic (February, 1913): “Kelp is apparently dead as far as the eastern end of Afognak.”

The human cost of the disappearance of kelp was described by George B. Rigg (Science, 1914) visiting the area in July of 1913 a year after the eruption when its effects were still profound. It was also noted that in 1912 when the grasses for pasturing cows were destroyed by the two feet of volcanic ash that fell on everything, the remaining cows lived on what kelp they could forage on the beach. But one year later, in 1913, Rigg pronounced the kelps were well on their way to recovery. The power of cold ocean, time and kelp’s inherent resilience allowed the nearshore ecology to recover quickly from this cataclysmic event. 

Green urchin barren have devastated kelp forests and are grazing down the historic and significant reefs of coralline algae, Clathromorphum nereostratum.

Photo by Joe Tomoleoni, USGS

Today, as we reach the western point of the bull kelps range, we ask if it is, in fact, still there at Umnak Island? That answer is yes! But we know that farther west the rich algal world of the Western Aleutian Island’s kelp forests has been devastated, reduced by urchin grazing to coralline encrusted rock. Here it is the green urchin that dominates the urchin barrens. And as the lack of sea otters persists—a long-term trickle down effect of human industrial whaling practices decades ago—the  urchins are grazing down even that long-lived “living rock,” the calcified coralline reef built over millennia. 

Can bull kelp recover from cataclysmic events today? Is the slow rise in sea temperature something the great bull kelp can withstand to continue to create its productive kelp forests? Is the Nereocystis kelp bed at Umnak Island as robust today as in past years? Can the algal life of the Western Aleutians return? While proposals are written and money and people allocated to restore kelp along California and Oregon’s coastlines, there are few people raising the alarm at the devastation under the waves in the Aleutians, despite intense scrutiny by fisheries experts. Searching for more recent kelp and algae information is hard. The 2022 NOAA Aleutian Islands Ecosystem report issues an in-brief, graphically stunning, 4-page report (with lots of icons of sea lions and birds and fishes), as well as a 227-page detailed report on ecosystems in the Aleutian Islands. Neither sea otter, sea urchin, nor algae of any kind, kelp or otherwise, are mentioned in either document. As we debate whether us humans can in fact “save” nature, we at least should be keeping watch and noticing the changes our human hubris has created. 

Bull kelp with herring roe
Photo by Josie Iselin

Bull kelp with herring roe, Afognak Island, June 2021 

Photo by Josie Iselin

To the east in Kodiak and at Afognak, there are folks watching. Patrick Saltonstall, an archeologist with the Alutiiq Museum in Kodiak, is keeping a personal log about the encroachment of Macrocystis into a single, formerly Nereocystis-dominated, bay at Afognak Island. His friend, Gayla Pedersen, has gained traditional ecological knowledge of plants and healing from her Alutiiq elders and taken on learning and experimenting with the marine algae including nasquluq. Her kelp pickle is renowned in the community. And a quick dive under the waves at Afognak reveals the bounty that these cold Alaskan waters produce when all the components, all the characters, play out the drama of the kelp forest. Perhaps nothing symbolizes this richness more than herring roe on kelp blades. In Tlingit and Haida culture, herring roe on Macrocystis blades is a subsistence staple, a tasty and healthy first food. When herring roe is encountered tucked as jewels between bulb and blade of Nereocystis, it is simply a gem evoking the fecundity of life in the mysterious world of bull kelp.


This is just the beginning. Please go to our Southwest Alaska Resources Page to learn more about the kelp work being done in this region.