The animals float passively on the water – just like the garbage. Fishing out the plastic is therefore well intentioned, but dangerous for the living beings. And against pollution other things would be much more effective anyway.
Humans have dumped 180 million tons of plastic into the oceans since 1950. It collects particularly densely in certain places, the so-called garbage vortices. “Müllstrudel” or “garbage patch” in English – that sounds like a floating island made of plastic bottles, yoghurt pots and flip-flops. But there is no continuous carpet of garbage and only a few objects the size of a bottle. Most of the plastic parts in the vortex are tiny: microplastics.
The media-effective action had a scientific benefit. Lecomte took samples that US marine biologist Rebecca Helm evaluated Has.
One might think that a plastic vortex is a very hostile environment. But Helm and her colleagues discovered that life raged between the plastic – in rather special forms.
The Portuguese galley (Physalia physalis)
Visible part as big as a full diaper
At first glance, the Portuguese galley looks like a jellyfish. But she is not a single animal; rather, you have to imagine them as a commune: several differently looking individuals live together in a small space and with a lot of physical contact, and each has its specialized task. One builds the house, one brings in the food. Neither can live without the other. Unlike most human communes, the Portuguese galley has only one eating and one having sex.
As with any regular commune, it is not entirely clear how many residents the Portuguese galley actually has, and there are members whose function is unknown. What can be said: The sub-organisms of this strange animal are genetically identical, but look completely different.
There is the balloon-like floating body filled with gas, on the top of which a crescent-shaped sail is erected when the wind blows. Partly transparent, partly colored blue, violet or pink, this structure floats on the water surface. It is to this part that the animal’s unusual name refers: its shape resembles a 15th-century Portuguese warship.
The other commune members hang on the underside of this raft. The eating polyps, which digest the prey, and the reproductive organs, so-called gonophores, are rather inconspicuous. But then there are those who get the food. The tentacles do that. They grow to an average length of 10 meters, but specimens of 30 meters or more have been observed. Not only are they gigantic in size in relation to the body they float, but they are deadly to almost anything that gets in their way. Because the threads contain a strong nettle toxin. Even large fish can be caught in this way, pulled up and eaten.
The venom can be dangerous even in torn tentacles or dead specimens washed up on the beach. In rare cases they are already people died from it. However, the intense pain and wheals that form on the affected skin are reason enough to stay away from this animal.
The Portuguese galley belongs to a group of animals called Neuston. The word is derived from the Greek νέω (néo), which means both «to swim» and «to float». Because that’s what these animals do: They drift without their own drive. In this respect, they are just like plastic waste.
The fact that the garbage is concentrated in certain places is related to the ocean currents. Because of the Earth’s rotation and the resulting wind system, there are five major circular currents in the world’s oceans; in the northern hemisphere, they rotate clockwise. The water is pushed to the center of the circle. Because it cannot escape upwards, it sinks downwards and eddies form like the drain in a bathtub. Plastic parts (and neuston) can no longer get out of these vortices.
According to estimates, there are up to 1 million pieces of plastic floating around in the North Pacific per square kilometer, i.e. one piece per square meter. However, these are then only parts that are lighter than water (and which receive disproportionately more attention).
Scientists assume that over time most plastic will sink to the bottom. After all, they have to be somewhere, the 180 million tons that are already in the oceans and the 11 million tons of plastic waste that end up in it every year. Because if you extrapolate the various samples, “only” 270,000 tons of plastic are floating on the surface, in 5.25 trillion mostly very small pieces. The rest is probably in the deep sea, which makes up most of the sea. But this part is invisible to us and can hardly be explored: taking samples at a depth of 4000 meters is very time-consuming.
The Sail Jellyfish (Velella velella)
As big as the lid of a small coffee mug
The Sailing Jellyfishalso called sailor before the wind, is like the Portuguese galley a colony, i.e. a community of different cnidarians. Compared to the deadly Portuguese galley, however, the jellyfish is gracefully harmless, unless you’re plankton, in which case you fall into that animal’s prey pattern. The sailing jellyfish consists of an elliptical plate of deep blue color on which a transparent, roughly triangular sail rises. Tentacles hang down into the water to catch prey. A single sailing jellyfish is a maximum of seven centimeters long, but it often occurs in large, large groups that floating on the water like living islands.
The fact that animals and plastic gather in the same place explains why seabirds such as albatrosses eat so much plastic and then die: they pounce on the neuston and catch the litter in the process. But the mixture of plastic and living beings has another consequence: fishing the plastic waste out of the sea, as some organizations are planning, will then most likely damage a lot of Neuston.
The violet snail (Janthina janthina)
As big as a ping pong ball
Not only can the violet snail not move by itself, it cannot even float on the surface of the water. At least not without a tool, which she produces herself: She forms a raft of air-filled bubbles from her slime, which she clings to for the rest of her life. There it hangs, with the tip of its purple shell, which is about four centimeters long, pointing downwards.
Their way of life may seem a bit awkward and that’s why appear less threatening. But this snail, which can’t even swim, feeds on sailfish — and Portuguese galleys. She is apparently immune to their deadly poison. She is by no means squeamish in other respects and cannibalically eats her own species. She has no problem with changing gender identities: she (or he) is first male, later female.
Boyan Slat from the Netherlands founded the organization The Ocean Cleanup in 2013. He has developed a floating barrier designed to collect plastic waste from the North Pacific. After many attempts, a working version is now in operation, but it will be further developed and then used on a much larger scale. However, many scientists are critical of the project. Helm’s study fuels her fears that neuston organisms can get stuck on the barrier and get crushed among the debris.
The much larger problems, namely the microplastics and the vast amounts of plastic on the seabed, cannot be solved with the system planned by Ocean Cleanup anyway. And the resources expended in labour, material and fuel to cover the gigantic distances, with the resulting CO2emissions – many scientists believe that all of this would be more sensibly invested elsewhere.
Numerous other organizations that originally wanted to collect garbage from the sea have since abandoned this plan. Instead, they now want to prevent the garbage from ending up in the sea in the first place. One already showed in 2016 Study, that this is more effective.
Blue Button (Porpita porpita)
As big as a candy wrapper
You can see immediately why Porpita porpita is called Blue Button in English: a flat, circular disc with a maximum diameter of five centimeters, grey-brown, nicely patterned with concentric circles and rays emanating from the middle, but the edge is a bright turquoise blue . The tentacles of this jellyfish-like creature are also turquoise and appear in the water like delicate feathers that are pushed in and out of the central disc in all directions in the water. Their nettle venom is harmless to humans but can cause skin irritation. Porpita also lives in the Mediterranean Sea.
Most plastic waste ends up in the sea in China and Southeast Asia, i.e. countries like Indonesia or Vietnam. It is often small local projects that have the greatest benefit, such as setting up a simple garbage disposal system. However, this does not look as spectacular as with Ocean Cleanup – and therefore receives less attention.
The Blue Dragon (Glaucus atlanticus)
As big as the lid of a drink bottle
One There are sea creatures that are smaller than almost all the others mentioned, only a maximum of three centimeters long, and they are not afraid of anything. Not from sailor jellyfish, not from violet snails and certainly not from Portuguese galleys. She eats them for breakfast, all of them. And as in the myths in which a bath in the enemy’s blood makes one invulnerable, she then tucks the nettle-cells with the deadly poison of the galleys into the ends of her extremities to protect herself.
This animal is called Glaucus atlanticus, it is a houseless sea snail, but the German term «blue dragon» is more accurate. Three pairs of wing-like extensions with a total of up to 80 “fingers” grow out of the elongated body of the snail. The body ends in a narrow pointed tail, the whole animal is colored in different shades of blue and white. The snail dragon hangs belly up at the bottom of the water surface, a bizarre little creature in the vast ocean.