A significant, previously unknown population of freshwater pearl mussel was found in the Ivalojoki watershed in Finnish Lapland. The cooperative Lumimuutos discovered it during restoration work in the Sámi homeland in summer 2025; authorities are withholding the exact location.

The invasive carpet sea squirt (filtsjöpung), known as “sea vomit,” is rapidly spreading across the seafloor in Kosterhavet National Park, smothering organisms beneath it. Authorities say budget cuts have hampered monitoring and control, but they are now examining ways to slow the outbreak.

The Metlakatla Indian Community, which has been at the forefront in the effort to control the invaders, has trapped more than 40,000 of them this year.

A rare Haliphron atlanticus (seven-arm octopus) was caught by shrimp fishers in western Skagerrak at about 200 m depth and sent to the Tjärnö Marine Laboratory for study.

Mowi Canada East reports 166,262 farmed salmon died at two sites near Chaleur Bay on Newfoundland’s south coast, blaming repeated sea lice infestations intensified by warm surface waters, low freshwater runoff, and calm winds. The incident follows earlier 2025 mass mortalities linked to a thermocline inversion and warm, low-oxygen conditions.

A crayfish plague caused by a water mould is devastating white-clawed crayfish in the River Maigue near Limerick, with locals reporting hundreds of deaths. Researchers are using environmental DNA to track the species and say reducing pollution could help remaining populations persist.

About 3.5 million liters of livestock-based biomanure leaked from Havila Biogass in Molde, spreading from a marsh into waterways and a small-boat harbor, causing fish and crab deaths. Norway’s Coastal Administration called it one of the largest such spills they’ve encountered and will order cleanup; the company is conducting remediation and investigating a failed pipe gasket as the likely cause.

Alaska health officials issued an alert after wild shellfish from Kachemak Bay’s inner bay tested above regulatory limits for paralytic shellfish poisoning toxins. Residents are warned not to harvest or eat untested wild shellfish; monitoring and test results are being posted by the Alaska Harmful Algal Bloom Network.

Barnacle larvae are proliferating in the Baltic Sea, prompting the Swedish Boat Union to warn owners to wash hulls in time to prevent hard barnacle mats and reduce environmental and fuel impacts.

Sea surface temperatures around the UK have been the warmest start to the year on record, driving unusual species like bluefin tuna, octopus and mauve stinger jellyfish into British and Irish waters. Irish waters have cooled since a May marine heatwave but remain above average in the east and south.

An unusual sighting of squid in Chignik Lagoon, Alaska, highlights a pattern of increasing squid observations in unexpected locations..

A venomous lion’s mane jellyfish has been sighted on several west Swedish beaches between Strömstad and Malmö, delivering powerful stings that can cause breathing problems.

A small but potentially environmentally threatening crab is expanding its area of influence in Alaska.

The Kachemak Bay National Estuarine Research Reserve detected Pseudo-nitzschia at bloom levels in Kachemak Bay starting July 4. This diatom can produce the toxin domoic acid, associated with amnesic shellfish poisoning, though toxin production is not yet confirmed. Observed bird deaths and marine mammal strandings have spurred collection of mussel samples for lab testing.

Sea surface temperatures off Norway have reached 22–23 °C, at least five degrees above normal, marking a marine heatwave that risks stressing marine life and intensifying extreme weather.

Tomtasjön, a lake north of Uppsala drained in the 1860s, has been restored to a 40-hectare waterbody. Landowners, with support from the County Administrative Board and EU funds, excavated the basin, and wildlife is now thriving.

A recent survey in Prince William Sound identified three new non-native species, including the newly discovered Monocorophium acherusicum, which may spread due to its adaptability to local conditions, prompting recommendations for ongoing monitoring and prevention efforts.

Oil products have been found washed up on five more coastal sites in the Temryuksky district and Anapa of the Krasnodar region. Local operational headquarters report that volunteers are already cleaning up these minor spills.

The storm event on October 21st brought an invasion of jellyfish to flooded areas. Eating jellyfishis thought to have resulted in one dog fatality, raising concerns for pet owners across Kotzebue.

A new plant species is establishing itself in the area and impacting native beach greens.