The new invasive bryozoan, Bugula neritina. (Courtesy Photo | Melissa Frey, Royal B.C. Museum via University of Alaska)

The new invasive bryozoan, Bugula neritina. (Courtesy Photo | Melissa Frey, Royal B.C. Museum via University of Alaska)

Invasive invertebrate discovered near Ketchikan

‘It’s really not known’ how Bugula neritina will change the ecosystem, scientist says, but the potential for harm is real

They’re called sea lace, moss animals and Bugula neritina to scientists — and they’re not supposed to be here.

But they are here, scientists say. The invasive species has been spotted in the southern reaches of coastal Alaska, a team of researchers has discovered.

According to a study published Sept. 27 in the academic journal Bioinvasions Records, the plant-like animal has been catalogued in Ketchikan for the first time ever. Invasive species, plants and animals that may move in to a geographic area where they aren’t indigenous, can sometimes wreak havoc on local ecosystems.

University of Alaska Fairbanks professor Gary Freitag, one of the study’s authors, said they don’t yet know how the sea lace will affect marine life around Ketchikan. There’s potential that it could do nothing, or it could outcompete native species for food or territory.

“We really don’t know the impacts of this,” Freitag said.

[Invasion from ‘Borg of the ocean’ baffles scientists]

The tiny organisms attach to hard surfaces like docks, rocks and the hulls of boats, forming colonies and filter-feeding off passing food particles.

The discovery comes from a year of analysis by a scientific team from the Smithsonian Environmental Research Center, Temple University and the UAF College of Fisheries and Ocean Sciences, where Freitag works as a marine advisor for the college’s Alaska Sea Grant.

The team suspended a series of small plastic plates around Ketchikan attached to bricks, Freitag said. Floating in the water column, the plates served as hosts to a smattering of sea species. The team then lab-analyzed the diversity of animals on the plates, providing them a picture of the different animals present near Ketchikan.

The team first encountered Bugula neritina in 2015 at Ketchikan’s Bar Harbor Marina, according to the paper.

The First City is the northern-most site for the study, which looked at biodiversity in marine waters in California, Panama and Mexico. The team wanted to find out how coastal marine life differs at different latitudes, Freitag said.

“There’s been a lot of theories as to whether diversity of organisms, the amount of organisms and the number of different species, varies with latitude in a region along the coastline. They were working out whether that theory is correct,” Freitag told the Empire in a Thursday phone interview.

The researchers don’t know why or how Bugula neritina moved north to Alaska. It could have arrived on the bottom of a passing vessel. Ketchikan is the first stop for foreign-flagged cruise ships and barges and fishing boats heading north.

Warming waters may be making the migration of invasive species easier, Freitag said. Several marine species new to Alaska, like market squid, are thought to have arrived here after chasing warmer waters north. Researchers believe Ketchikan is a bellwether for such migration.

The discovery is the northernmost record of Bugula neritina in the Pacific Ocean.

“I don’t know whether there’s any real, direct evidence that climate change is causing the spread of invasive species. It’s suspected very heavily, there’s indications that it plays a role,” Freitag said.

[Squid fishery proposed for Southeast]

Alaska has fewer non-indigenous marine species than any other coastal U.S. state, the team wrote, and Ketchikan is a “key location in Alaska for early detection of marine species with the potential to spread poleward from lower latitudes.”

The paper also documents the spread of several other invasive species in Ketchikan’s marine waters. Some of them are potentially problematic for native sea life, Freitag said.

The discovery marks the culmination of years of observation not only by professionals like Freitag, but citizen scientists who’ve tracked invasive species in Ketchikan since at least 2003.

The team documented the continuing spread of three non-indigenous tunicates, invertebrates known as sea squirts. One of those species, Ciona savignyi, the Pacific transparent sea squirt, hasn’t been documented in Alaska waters since 1903.

Sea squirts can cause problems for coastal economies in ground fisheries and oyster and other mariculture farms. Freitag said they haven’t yet documented any adverse effects from the Bugula neritina or any of the sea squirt species. But the potential for disruption is there.

“It’s really not understood what the potential dangers are of any of this stuff, but it potentially has a lot of impact,” Freitag said.


• Contact reporter Kevin Gullufsen at 523-2228 and kgullufsen@juneauempire.com. Follow him on Twitter at @KevinGullufsen.


Another rare invasive species, the sea squirt Ciona savignyi. (Courtesy Photo | Melissa Frey, Royal B.C. Museum via University of Alaska)

Another rare invasive species, the sea squirt Ciona savignyi. (Courtesy Photo | Melissa Frey, Royal B.C. Museum via University of Alaska)

One of the fouling panels used in the experiment. (Courtesy Photo | Gary Freitag).

One of the fouling panels used in the experiment. (Courtesy Photo | Gary Freitag).

A crab covered in Botrylloides, found in Ketchikan. (Courtesy Photo | Gary Freitag via University of Alaska)

A crab covered in Botrylloides, found in Ketchikan. (Courtesy Photo | Gary Freitag via University of Alaska)

More in News

(Juneau Empire file photo)
Aurora forecast for the week of Feb. 26

These forecasts are courtesy of the University of Alaska Fairbanks’ Geophysical Institute… Continue reading

Alaska Department of Transportation and Public Facilities Commissioner Ryan Anderson answers questions from state senators during a Senate Finance Committee hearing on Wednesday. (Mark Sabbatini/Juneau Empire)
State officials working to meet Friday deadline for revised transportation plan

The federal government rejected the plan on Feb. 9, citing numerous deficiencies

(Getty Images)
Alaska Republicans head to the polls Tuesday with Trump, Haley and Ramaswamy on the ballot

On Super Tuesday, March 5, Alaska Republicans will join their counterparts in… Continue reading

Rep. Kevin McCabe, R-Big Lake, speaks March 20, 2023, on the floor of the Alaska House. (Photo by James Brooks/Alaska Beacon)
Proposal to define a fetus as a person in Alaska’s criminal code faces pushback

Opponents testified that the bill would threaten Alaskans’ abortion rights

Rep. Justin Ruffridge, R-Soldotna, speaks Monday, May 8, 2023, on the floor of the Alaska House. (Photo by James Brooks/Alaska Beacon)
Alaska House approves bigger merit scholarship for in-state high school students

The Alaska House of Representatives voted on Monday without opposition to raise… Continue reading

A mountain biker takes advantage of a trail at Eaglecrest Ski Area during the summer of 2022. The city-owned resort is planning to vastly expand its summer activities with a new gondola and the facilities by 2026. (City and Borough of Juneau photo)
Eaglecrest’s big summertime plans, including the gondola, get OK from planning commission

Ski area also planning new summit lodge, snowtubing park, bike trails and picnic pavilion by 2026.

Spruce Root was invited by the U.S. Forest Service to help roll out the Tongass National Forest Plan Revision process. (Photo by Bethany Goodrich)
Resilient Peoples and Place: Stronger Together in 2024 — A letter from the Sustainable Southeast Partnership

Founded in 2012, the Sustainable Southeast Partnership (SSP) is an Indigenous values-led… Continue reading

Students, parents and teachers rally outside Juneau-Douglas High School: Yadaa.at Kalé prior to a school board meeting Tuesday, seeking a change in the board’s decision to consolidate Juneau’s two high schools beginning with the next school year. (Mark Sabbatini / Juneau Empire)
Layoffs and larger classes planned along with consolidation at local schools, but BSA increase would help

District leaders not counting on funds approved by Legislature, due to veto threat by governor.

(Michael Penn / Juneau Empire file photo)
Police calls for Monday, Feb. 26, 2024

This report contains public information from law enforcement and public safety agencies.

Most Read