Snot (Alga/Microorganisms)

Rock Snot - Didymosphenia geminata, commonly known as didymo, is a species

of diatom that produces nuisance growths in freshwater rivers and streams with consistently cold water temperatures and low nutrient levels. It is native to the northern hemisphere, and considered an invasive species in Australia, Argentina, New Zealand, and Chile. Even within its native range, it has taken on invasive characteristics since the 1980s. It is not considered a significant human health risk, but it can affect stream habitats and sources of food for fish and make recreational activities unpleasant. This microscopic alga can be spread in a single drop of water.

Native range

The native distribution of D. geminata is the cool temperate regions of the Northern Hemisphere, including the rivers of northern forests and alpine regions of Europe, Asia and parts of North America.

Until its recent discovery in New Zealand, where it was introduced, it was never previously found in the Southern Hemisphere. The distribution of didymo in the last two decades appears to be gradually expanding outside its native range. Even within its native range, there have been reports of excessive growths in areas where it previously existed only in low concentrations.

Adverse effects

Didymo can have a notable impact on the insects that are a food source for many species of fish. It can form massive algal blooms. It makes riverbeds slippery posing a danger to waders and swimmers. Didymo blooms also pose a hazard for: hydroelectric power generation, irrigation and recreational water usage.

Preventing further spread

The following methods have been recommended to prevent the spread of didymo in New Zealand:

Check: Before leaving the river, remove all obvious clumps of algae and look for hidden clumps. Leave them at the site. If you find clumps later don't wash them down the drain, treat them with the approved methods below, dry them and soak them in bleach for at least 4 hours.

Clean: Soak and scrub all items for at least one minute in either hot (60 °C) water, a 2% solution of household bleach, antiseptic hand cleaner, or dishwashing detergent.

Dry: If cleaning is not practical (e.g. livestock, pets), after the item is completely dry wait an additional 48 hours before contact or use in any other waterway.

New Zealand and the U.S. states of Alaska, Maryland, South Dakota and Vermont have banned anglers from wearing felt-soled boots. Orvis, a leading U.S. manufacturer of fly-fishing equipment, has started selling more rubber-soled boots than felt-soled.

Sea Snot - Marine mucilage, or sea saliva is a collection of mucus-like organic matter found in the

sea. The creamy, gelatinous substance is generally not harmful, but can attract viruses and bacteria, including E. coli, and it can become a blanket that suffocates the marine life below. It is frequently seen in the Mediterranean Sea and has recently spread to the Sea of Marmara.

Causes

Marine mucilage, also called sea snot, "is essentially a mass of microorganisms enriched by components of excessive nutrients from untreated waste discharged into the sea." Professor Hüseyin Erduğan

from Çanakkale Onsekiz Mart University's Department of Biology, explains that "the mucilage is actually an exopolysaccharide (a biomacromolecule composed of carbohydrate residues emitted by microorganisms) and that while pollution did aggravate the sea snot problem, it was ultimately caused by those microorganisms." The increase in sea snot is due to the large increase of phosphorus (phosphorus values were measured to be three to four times higher than previous year) and other excessive nutrients combined with drought conditions and with prolonged warm temperatures and calm weather. Globs of marine snow coagulate into large blobs that can span distances as large as 125 miles (200 km). The mucilage has many components, including a wide range of microorganisms including viruses and prokaryotes, and exopolymeric compounds with colloidal properties. Sea snot is also produced by phytoplankton when they are stressed.

Effects

The significant increase in the amount of sea snot in 2021 in Turkey suddenly became a political issue as well as an environmental issue. The growth in snot that year was exponential as it reached a tipping point in the Mediterranean and other seas. Sea snot was observed clumping at least as early as 2009. Some overgrowth is partly due to climate change. Warmer, slower moving waters increase the production of sea snot and allow it to accumulate in massive blobs. Sea snot was first reported in 1729 and has long been seen as a nuisance to the fishing industry and coastal populations. Recently, sea snot has emerged not only as a nuisance, but as a major hazard. Its not just that globs of snot can harbor bacteria such as E. coli which threaten maritime flora and fauna, as well as humans exposed to contaminated water but sea snot can also coat the gills of sea creatures subsumed in it, cutting off oxygen and killing them.

The Deepwater Horizon oil spill in the Gulf of Mexico created large amounts of sea snot. Scientists are not sure how exactly the spill caused so much sea snot to form, but one theory asserts that the sea snot could have been the result of a massive kill of microscopic marine life creating a "blizzard" of marine snow. Scientists worry that the mass of sea snot could pose a biohazard to surviving marine life in the area. It is widely believed that the sea snot left by the spill directly resulted in the loss of sea life in the Gulf of Mexico, as evidenced by a dead field of deepwater coral 11 kilometers from the Deepwater Horizon station.

In early 2021, sea snot spread in the Sea of Marmara, due to pollution from wastewater dumped into seawater, which led to the proliferation of phytoplankton, and posed a great threat to the marine biome. The port of Erdek at the Sea of Marmara was covered by the sea snot, in which Turkish workers embarked on a massive effort to vacuum up the slimy marine mucilage in June 2021. At that time it was not clear how to remove the underwater mucilage. Yalıköy port in Ordu Province also witnessed accumulating mucilage in June 2021, in the Black Sea.

Countermeasures

Short-term countermeasures include collecting it from the sea surface and laying barriers on the sea surface. Long-term countermeasures include improving wastewater treatment, creating marine protected areas, and limiting climate change. Another effort could be developing such water bodies as tourist hubs so that waters do not remain stagnant for long which contributes for accumulation of sea snot. Another one could be introducing such marine species in the sea which could consume excessive nutrients, for cleaning purpose only and later keeping them in artificially developed habitats.