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52 st / March 2015 www.sea-technology.com Sticklebacks Inherit Adaptability To Warmer Waters Researchers at the Alfred Wegener Institute, Helmholtz Centre for Po- lar and Marine Research (AWI) have shown that three-spined sticklebacks in the North Sea pass on environmen- tal information to their offspring, with- out genetic changes. This could play an important role in the species' abil- ity to adapt to the effects of climate change, reports a study in Functional Ecology. For the North Sea, a habitat for three-spined stickleback, climate models predict a rise in mean summer water temperatures from 17° to 21°C by the year 2100. Researchers kept female and male sticklebacks in either 17° or 21°C water for their experiments. After two months, the fsh were mated within and between their acclimation tem- peratures. The offspring were subse- quently raised in 17° or 21°C water. After 30 days, offspring that grew in water with the same temperature as their mothers displayed the best growth rates. Offspring that live in the same conditions as their mothers showed an optimized metabolism. Through her mitochondria, the mother shares information on the environment with her offspring, which produces a last- ing effect. This mechanism works particularly well in less favorable en- vironments, which for sticklebacks means warmer waters. Hopkins' Rose Nudibranch Could Signal Warming Climate The warm ocean temperatures that brought a green sea turtle to San Fran- cisco in September and other south- ern species north of their usual ranges on the Pacifc Coast have triggered a population explosion of a bright pink, inch-long sea slug in tide pools along the central and northern California coast. The Hopkins' Rose nudibranch (Okenia rosacea) is common to south- ern California but found only sporadi- cally in central California and rarely north of San Francisco. However, in the past few weeks, researchers from University of California Santa Barbara (UCSB), University of California Santa Cruz, the Bodega Marine Laboratory and the California Academy of Sci- ences have reported densities of up to dozens per square meter in tide pools from San Luis Obispo to Humboldt counties. These are the highest num- bers and northernmost records of this species seen since the strong El Niños of 1998 and 1983. But there is currently no El Niño. The current population bloom of Hop- kins' Rose is similar to the one on the central coast in 1977, which occurred also during a weak El Niño and coin- cided with a major climate shift in the eastern Pacifc Ocean. This triggered range deviations in numerous coastal species. Fluctuations in the abun- dance of intertidal adults of Hopkins' Rose and other nudibranchs in central California were driven by regional oceanographic infuences on currents and larval recruitment, researchers ar- gued. They predicted high recruitment of these nudibranchs when warm temperatures, northward-directed currents and weak upwelling occur— which is what is happening now. Because Hopkins' Rose nudi- branchs are fast-growing, live for a year max and move little as adults, they are potentially useful in track- ing relatively rapid changes in ocean conditions. They might currently be signaling another major climate shift from cold to warm. Slope Found to Lower Europe's Sea Level The U.K. National Oceanogra- phy Centre (NOC) has discovered that a slope on the ocean surface in the Strait of Gibraltar is lowering the sea level in Europe by 7 centimeters. This research, which was published by Geophysical Research Letters, will help to more accurately predict future sea levels by providing a more com- plete understanding of the factors that control it. The rotation of the Earth causes ocean currents in the northern hemi- sphere to slope as they fow, with a low in the sea level on their left hand side. A current of water, equivalent to four Amazon rivers, is fowing into the Mediterranean from the Atlantic, re- turning below the surface. This surface fow means that sea level must drop to the north, across the Strait of Gi- braltar. Researchers were able to dis- cover a simple relationship between the drop in sea level and the strength of fow of the ocean current. This rela- tionship suggested that the sea level in Portugal should be about 7 centime- ters lower than that on the Moroccan coast. With the help of new satellite gravity measurements, from the Euro- pean Space Agency's GOCE satellite as well as the NASA/DLR GRACE sat- ellite, researchers measured this sea level drop. The gravity feld measured by these satellites provides data on where the sea surface would be if no slopes existed in the ocean. By com- paring this with the actual sea surface level, measured using satellite altim- etry and tide gauges, it was possible to estimate the drop in sea level caused by the swirling currents. Sulfate-Breathing Microbes Can Break Down Carbon Two miles below the surface of the ocean, researchers have discovered new microbes that breathe sulfate. The study was published by Frontiers in Microbiology. The microbes, which have yet to be classifed and named, exist in massive undersea aquifers. About one-third of the Earth's biomass is thought to exist in this largely un- charted environment. Researchers from the University of Southern California and the University of Hawaii took their samples from the Juan de Fuca Ridge (off the coast of Washington state). Circulation Obvia- tion Retroft Kit observatories created a seal at the seafoor, allowing scien- tists to deploy instruments and sam- pling devices down a borehole while keeping ocean water out. Samples were then shuttled to the surface by remote-controlled undersea vehicles or "elevators"—balloons that drop ballast and foat samples gently up to the waiting scientists. The microbes in the undersea aqui- fers can use sulfate to break down carbon from decaying biological ma- terial that sinks to the sea bottom and makes its way into the crustal aquifer, producing carbon dioxide. Learning how these new microbes function will be important to getting a more accurate, quantifed under- standing of the overall global carbon cycle, which is currently being dis- rupted by man-made carbon dioxide emissions. n ocean research