{"290291":{"#nid":"290291","#data":{"type":"news","title":"Fish From Acidic Ocean Waters Less Able to Smell Predators","body":[{"value":"\u003Cp\u003EFish living on coral reefs where carbon dioxide seeps from the ocean floor were less able to detect predator odor than fish from normal coral reefs, according to a new study.\u003C\/p\u003E\u003Cp\u003EThe study confirms laboratory experiments showing that the behavior of reef fishes can be seriously affected by increased carbon dioxide concentrations in the ocean. The new study is the first to analyze the sensory impairment of fish from CO\u003Csub\u003E2 \u003C\/sub\u003Eseeps, where pH is similar to what climate models forecast for surface waters by the turn of the century.\u003C\/p\u003E\u003Cp\u003E\u0022These results verify our laboratory findings,\u0022 said \u003Ca href=\u0022http:\/\/www.biology.gatech.edu\/people\/danielle-dixson\u0022\u003EDanielle Dixson\u003C\/a\u003E, an assistant professor in the School of Biology at the Georgia Institute of Technology in Atlanta. \u0022There\u0027s no difference between the fish treated with CO\u003Csub\u003E2\u003C\/sub\u003E in the lab in tests for chemical senses versus the fish we caught and tested from the CO\u003Csub\u003E2\u003C\/sub\u003E reef.\u0022\u003C\/p\u003E\u003Cp\u003EThe research was published in the April 13 Advance Online Publication of the journal \u003Ca href=\u0022http:\/\/dx.doi.org\/10.1038\/NCLIMATE2195\u0022\u003E\u003Cem\u003ENature Climate Change\u003C\/em\u003E\u003C\/a\u003E. Philip Munday, from \u003Ca href=\u0022http:\/\/www.jcu.edu.au\/mtb\/staff\/az\/JCUDEV_016582.html\u0022\u003EJames Cook University in Australia\u003C\/a\u003E, was the study\u0027s lead author. The work was supported by the Australian Institute for Marine Science, a Grant for Research and Exploration by the National Geographic Society, and the ARC Centre of Excellence for Coral Reef Studies.\u003C\/p\u003E\u003Cp\u003E\u003C\/p\u003E\u003Cp\u003EThe pH of normal ocean surface water is around 8.14. The new study examined fish from so-called bubble reefs at a natural CO\u003Csub\u003E2\u003C\/sub\u003E seep in Papua New Guinea, where the pH is 7.8 on average. With today\u0027s greenhouse gas emissions, climate models forecast pH 7.8 for ocean surface waters by 2100, according to theIntergovernmental Panel on Climate Change (IPCC).\u003C\/p\u003E\u003Cp\u003E\u0022We were able to test long-term realistic effects in this environment,\u0022 Dixson said. \u0022One problem with ocean acidification research is that it\u0027s all laboratory based, or you\u0027re testing something that\u0027s going to happen in a 100 years with fish that are from the present day, which is not actually accurate.\u0022\u003C\/p\u003E\u003Cp\u003EPrevious research had led to speculation that ocean acidification might not harm fish if they could buffer their tissues in acidified water by changing their bicarbonate levels. Munday and Dixson were the first to show that fishes\u0027 sensory systems are impaired under ocean acidification conditions in the laboratory. \u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u0022They can smell but they can\u0027t distinguish between chemical cues,\u0022 Dixson said.\u003C\/p\u003E\u003Cp\u003ECarbon dioxide released into the atmosphere is absorbed into ocean waters, where it dissolves and lowers the pH of the water. Acidic waters affect fish behavior by disrupting a specific receptor in the nervous system, called GABA\u003Csub\u003EA,\u003C\/sub\u003E which is present in most marine organisms with a nervous system. When GABA\u003Csub\u003EA\u003C\/sub\u003E stops working, neurons stop firing properly.\u003C\/p\u003E\u003Cp\u003ECoral reef habitat studies have found that CO\u003Csub\u003E2\u003C\/sub\u003E-induced behavioral changes, similar to those observed in the new study, increase mortality from predation by more than fivefold in newly settled fish.\u003C\/p\u003E\u003Cp\u003EFish can smell a fish that eats another fish and will avoid water containing the scent. In Dixson\u0027s laboratory experiments, control fish given the choice between swimming in normal water or water spiked with the smell of a predator will choose the normal water. But fish raised in water acidified with carbon dioxide will choose to spend time in the predator-scented water.\u003C\/p\u003E\u003Cp\u003EJuvenile fish living at the carbon dioxide seep and brought onto a boat for behavior testing had nearly the identical predator sensing impairment as juvenile fish reared at similar CO\u003Csub\u003E2 \u003C\/sub\u003Elevels in the lab, the new study found.\u003C\/p\u003E\u003Cp\u003EThe fish from the bubble reef were also bolder. In one experiment, the team measured how far the fish roamed from a shelter and then created a disturbance to send the fish back to the shelter. Fish from the CO\u003Csub\u003E2\u003C\/sub\u003E seep emerged from the shelter at least six times sooner than the control fish after the disturbance.\u003C\/p\u003E\u003Cp\u003EDespite the dramatic effects of high CO\u003Csub\u003E2\u003C\/sub\u003E on fish behaviors, relatively few differences in species richness, species composition and relative abundances of fish were found between the CO\u003Csub\u003E2\u003C\/sub\u003E seep and the control reef.\u003C\/p\u003E\u003Cp\u003E\u0022The fish are metabolically the same between the control reef and the CO\u003Csub\u003E2 \u003C\/sub\u003Ereef,\u0022 Dixson said. \u0022At this point, we have only seen effects on their behavior.\u0022\u003C\/p\u003E\u003Cp\u003EThe researchers did find that the number of large predatory fishes was lower at the CO\u003Csub\u003E2 \u003C\/sub\u003Eseep compared to the control reef, which could offset the increased risk of mortality due to the fishes\u0027 abnormal behavior, the researchers said.\u003C\/p\u003E\u003Cp\u003EIn future work, the research team will test if fish could adapt or acclimate to acidic waters. They will first determine if the fish born at the bubble reef are the ones living there as adults, or if baby fish from the control reef are swimming to the bubble reef.\u003C\/p\u003E\u003Cp\u003E\u0022Whether or not this sensory effect is happening generationally is something that we don\u0027t know,\u0022 Dixson said.\u003C\/p\u003E\u003Cp\u003EThe results do show that what Dixson and colleagues found in the lab matches with what is seen in the field.\u003C\/p\u003E\u003Cp\u003E\u0022It\u0027s a step in the right direction in terms of answering ocean acidification problems.\u0022 Dixson said. \u0022The alternative is just to wait 100 years. At least now we might prepare for what might be happening.\u0022\u003C\/p\u003E\u003Cp\u003E\u003Cem\u003EThis research is supported by the Australian Institute for Marine Science, a Grant for Research and Exploration by the National Geographic Society, and the ARC Centre of Excellence for Coral Reef Studies. Any conclusions or opinions are those of the authors and do not necessarily represent the official views of the sponsoring agencies.\u003C\/em\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003ECITATION\u003C\/strong\u003E: Philip L. Munday, et al., \u0022Behavioural impairment in reef fishes caused by ocean acidification at CO2 seeps.\u0022 (\u003Cem\u003ENature Climate Change\u003C\/em\u003E, April 2014). \u003Ca href=\u0022http:\/\/dx.doi.org\/10.1038\/NCLIMATE2195\u0022\u003Ehttp:\/\/dx.doi.org\/10.1038\/NCLIMATE2195\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EResearch News\u003Cbr \/\u003E Georgia Institute of Technology\u003Cbr \/\u003E 177 North Avenue\u003Cbr \/\u003E Atlanta, Georgia\u0026nbsp; 30332-0181\u0026nbsp; USA\u003Cbr \/\u003E \u003C\/strong\u003E\u003Ca href=\u0022https:\/\/twitter.com\/GTResearchNews\u0022\u003E\u003Cstrong\u003E@GTResearchNews\u003C\/strong\u003E\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EMedia Relations Contacts\u003C\/strong\u003E: Brett Israel (\u003Ca href=\u0022https:\/\/twitter.com\/btiatl\u0022\u003E@btiatl\u003C\/a\u003E) (404-385-1933) (\u003Ca href=\u0022mailto:brett.israel@comm.gatech.edu\u0022\u003Ebrett.israel@comm.gatech.edu\u003C\/a\u003E) or John Toon (404-894-6986) (\u003Ca href=\u0022mailto:jtoon@gatech.edu\u0022\u003Ejtoon@gatech.edu\u003C\/a\u003E)\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EWriter\u003C\/strong\u003E: Brett Israel\u0026nbsp;\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":[{"value":"Oddly behaving fish from a CO2 seep confirm laboratory experiments"}],"field_summary":[{"value":"\u003Cp\u003EFish living on coral reefs where carbon dioxide seeps from the ocean floor were less able to detect predator odor than fish from normal coral reefs, according to a new study.\u003C\/p\u003E\u003Cp\u003EThe study confirms laboratory experiments showing that the behavior of reef fishes can be seriously affected by increased carbon dioxide concentrations in the ocean. The new study is the first to analyze the sensory impairment of fish from CO\u003Csub\u003E2\u0026nbsp;\u003C\/sub\u003Eseeps, where pH is similar to what climate models forecast for surface waters by the turn of the century.\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Fish living on coral reefs where carbon dioxide seeps from the ocean floor were less able to detect predator odor than fish from normal coral reefs, according to a new study."}],"uid":"27902","created_gmt":"2014-04-14 09:55:38","changed_gmt":"2016-10-08 03:16:15","author":"Brett Israel","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2014-04-14T00:00:00-04:00","iso_date":"2014-04-14T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"290271":{"id":"290271","type":"image","title":"Damselfishes","body":null,"created":"1449244274","gmt_created":"2015-12-04 15:51:14","changed":"1475894888","gmt_changed":"2016-10-08 02:48:08","alt":"Damselfishes","file":{"fid":"199216","name":"dascyllus.jpg","image_path":"\/sites\/default\/files\/images\/dascyllus_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/dascyllus_0.jpg","mime":"image\/jpeg","size":45607,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/dascyllus_0.jpg?itok=zFAfUR-F"}},"251891":{"id":"251891","type":"image","title":"Danielle Dixson","body":null,"created":"1449243813","gmt_created":"2015-12-04 15:43:33","changed":"1475894931","gmt_changed":"2016-10-08 02:48:51","alt":"Danielle Dixson","file":{"fid":"198126","name":"danielle.dixson.jpg","image_path":"\/sites\/default\/files\/images\/danielle.dixson_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/danielle.dixson_0.jpg","mime":"image\/jpeg","size":251630,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/danielle.dixson_0.jpg?itok=ftrnOC13"}}},"media_ids":["290271","251891"],"groups":[{"id":"1188","name":"Research Horizons"}],"categories":[{"id":"154","name":"Environment"},{"id":"146","name":"Life Sciences and Biology"}],"keywords":[{"id":"91471","name":"bubble reef"},{"id":"91481","name":"carbon seep"},{"id":"831","name":"climate change"},{"id":"14760","name":"coral reef"},{"id":"91461","name":"damselfishes"},{"id":"91451","name":"fishes"}],"core_research_areas":[],"news_room_topics":[{"id":"71911","name":"Earth and Environment"}],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003EBrett Israel\u003C\/p\u003E\u003Cp\u003E404-385-1933\u003C\/p\u003E\u003Cp\u003E\u003Ca href=\u0022https:\/\/twitter.com\/btiatl\u0022\u003E@btiatl\u003C\/a\u003E\u003C\/p\u003E","format":"limited_html"}],"email":["brett.israel@comm.gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}