Discovered in Green: The jellyfish are multiplying, rivers might be a good place to get electric power, hydroelectric dams aren't so good for the environment, and bird poop proves DDT hurt bird population. 

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    Wait, those jellyfish we thought weren't taking over are actually taking over. The other week, science gave us what now sounds like fake good news. The stingy-jellied monsters haven't multiplied, research said. Research lied! "There has been anecdotal evidence that jellyfish were on the rise in recent decades, but there hasn't been a global study that gathered together all the existing data until now," explains researcher Lucas Brotz. Right, and then in February science proved all those stories false, right? Wrong: "Our study confirms these observations scientifically after analysis of available information from 1950 to the present for more than 138 different jellyfish populations around the world," he continues. Ugh. Gross. Oh, and by the way, this new source of anxiety for a certain swimmer is all your fault. "We can also see that the places where we see rising numbers of jellyfish are often areas heavily impacted by humans, through pollution, overfishing, and warming waters," notes Brotz. Way to go, humans. [University of British Columbia]
  • Getting electricity from rivers. The hydro-electric sort, of course Why hasn't science already thought of this? That's how Niagara Falls does it, right? Well a new sort of generator would make it possible and efficient to harvest the energy of rivers flowing into oceans. Guess nothing right now can do that. The new device, however, would using just one-tenth of the world's rivers, generate power to 520 million people, without emitting any CO2. "The same amount of electricity, if produced by a coal-fired power plant, would release over one billion metric tons of greenhouse gases each year," explains the research write-up. Sounds like a good deal. So, what's the catch?  [Environmental Science & Technology]
  • Hydroelectric dams aren't good for the Amazon. The benefits of getting clean hydroelectric power from dams set up in the Amazon might be offset by the ecological damages they're creating. Over 80 percent of the proposed dams would contribute to forest loss and the blockades, on top of blocking water from getting to places it needs to go.  "We conclude that there is an urgent need for strategic basin scale evaluation of new dams and a plan to maintain Andes-Amazon connectivity," explains researcher Dr. Clinton Jenkins. "We also call for a reconsideration of the notion that hydropower is a widespread low-impact energy source in the Neotropics," he continues. Sounds like something for our river generators above to think on before they mess with those rivers. [PLos One]
  • Bird poop proves DDT was an issue for bird population. Looking at bird crap is nasty, researchers have discovered. "It may be a stinky job, but someone has to do it!" explains researcher John P. Smol, who after looking through harvested bird poo, found that DDT caused a change in the diet of birds. Specifically, DDT decreased the beetle population, which meant the feathery creatures had to eat other stuff instead, which means the whole circle of life was off balance because of the chemical. Thank goodness for that Joni Mitchel song, or who knows what birds would have started eating next. [Proceedings of the Royal Society B]