The seabed out there is sand.<\/p>\n
Flat, shifting, poor in anything that will hold still long enough for a larva to glue itself down, which is the condition most of the southern North Sea floor is in.<\/p>\n
Then somebody moored a power station on top of it.<\/p>\n
The underside of that structure is hard and stable<\/strong>, sits in the brightest few feet of the water column, and has no natural equivalent for miles in any direction.<\/p>\n It did not stay empty long.<\/p>\n Within eight months<\/strong> of the first units going in, the wet side had a community on it dense enough to need a scraper<\/strong> and a frame to measure.<\/p>\n Most of the animals here arrive as larvae, not adults.<\/p>\n They drift in the plankton for days or weeks, sampling surfaces chemically as they go, and they settle where the substrate is hard and the light is low.<\/p>\n An underside is both of those at once.<\/p>\n Blue mussels, barnacles and tube worms want shade and grip<\/strong>, and a float delivers the pair together in water where the natural bottom offers neither of them<\/strong>.<\/p>\n Then the structure feeds itself.<\/p>\n Mussels filter plankton out of the passing water and the amphipods build tubes in the gaps between the shells, so each layer of growth creates more surface<\/strong> for the next one to land on.<\/p>\n The site is 7.5 miles off The Hague, in water somewhere between 39 and 66 feet deep.<\/p>\n Twenty eight floats sit there, presenting a submerged area of roughly 115 by 56 feet<\/strong> to whatever swims past.<\/p>\n They did not all go in together.<\/p>\n One batch was moored in January and a second in June, which handed the researchers an accidental experiment in time submerged<\/strong> without anyone planning it.<\/p>\n Divers sampled them in early September.<\/p>\n Eighteen floats across three clusters, scraped inside a frame so that everything counted could be tied back to a known area<\/strong>.<\/p>\n Forty seven distinct taxa, of which only 28 could be pinned to species.<\/p>\n The rest stopped at genus or family, which is normal for fouling work and worth knowing before anyone repeats the figure as 47 species<\/strong>.<\/p>\n Arthropods won on headcount by a distance.<\/p>\n Tube building amphipods of the genus Jassa ran to 80,000 animals<\/strong> in a square yard on the older floats, against about 5,000 for every mollusc combined.<\/p>\n Molluscs won on weight.<\/p>\n Blue mussels dominated the biomass at roughly six ounces<\/strong> of dried tissue per square yard, which is what happens when a few thousand animals each carry a shell.<\/p>\n Twelve of those 28 named species are not native to the North Sea.<\/p>\n That is 43 percent<\/strong> of everything the team could put a species name to, on a structure that had been in the water for less than a year.<\/p>\n The dominant animal is one of them.<\/p>\n Jassa marmorata came from the western Atlantic, and the list around it includes a Japanese skeleton shrimp, a Japanese tube worm, an Australasian barnacle and a marine insect<\/strong> from the Pacific.<\/p>\n This is the part that should worry a regulator.<\/p>\n Hard structures in a sandy sea work as stepping stones<\/strong>, letting introduced species hop across open water they could not otherwise cross, and every new float extends the chain.<\/p>\n Steel monopiles do the same thing, as divers found when they logged 86 species<\/a> on turbines off Taiwan that had never been recorded there.<\/p>\n What the inventory<\/a> gives is a baseline, taken once, on a small farm.<\/p>\n It says nothing about engineering.<\/p>\n There is no load analysis in it, no discussion of what the growth weighs when the float is lifted, and no recommendation to any designer about carrying it.<\/p>\n The weight figure is also easy to misread.<\/p>\n Six ounces per square yard is ash free dry weight<\/strong>, meaning tissue with the shell and the water taken out, so the real hanging mass is a large multiple of it that nobody has published.<\/p>\n Scale it up and the gap matters.<\/p>\n The authors estimate a farm of about 69,000 square feet<\/strong> would carry on the order of 2,900 pounds of dried mussel tissue in its first year, which is a biology number rather than a design number.<\/p>\n The food chain is unproven as well.<\/p>\n A camera study<\/a> at the same site found gulls and seals using the platforms and one mussel in one bird pellet, without ever confirming the birds were feeding on the farm itself.<\/p>\n North Sea wind farms show the same seals arriving<\/a> once the mussels and barnacles are established.<\/p>\n So the honest reading is narrower than the headline.<\/p>\n One solar farm<\/strong>, sampled on a single September day, came back carrying a crowded and largely imported community that nobody has yet weighed properly.<\/p>\n","protected":false},"excerpt":{"rendered":" The seabed out there is sand. Flat, shifting, poor in anything that will hold still long enough for a larva to glue itself down, which is the condition most of the southern North Sea floor is in. Then somebody moored a power station on top of it. The underside of that structure is hard and stable, … Read more<\/a><\/p>\n","protected":false},"author":28,"featured_media":35276,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"rank_math_focus_keyword":"divers found 47","rank_math_title":"Divers scraped 18 floats under a solar farm 7.5 miles off the Dutch coast and counted 47 kinds of animal, with close to 80,000 shrimp like amphipods in every square yard of underside","rank_math_description":"Divers sampling 18 floaters on the first offshore solar farm in the Netherlands found 47 species living under the panels, with blue mussels dominating by","footnotes":""},"categories":[8],"tags":[],"class_list":["post-35182","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-energy"],"_links":{"self":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts\/35182","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/users\/28"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/comments?post=35182"}],"version-history":[{"count":0,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts\/35182\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/media\/35276"}],"wp:attachment":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/media?parent=35182"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/categories?post=35182"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/tags?post=35182"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Why the shady side fills up first<\/h2>\n
The thing being colonized<\/h2>\n
What came up in the frames<\/h2>\n
Where nearly half of them came from<\/h2>\n
What the study does not say<\/h2>\n