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Keeping Coral Clean Seaweed overgrowth is a major problem for coral reefs and also seems to be a consequence of excessive harvesting of herbivorous fish. Dixson and Hay (p. 804) examined this effect on Fijian reefs. Species of small herbivorous gobies and coral-associated damselfish were compared for their effect on the toxic Chlorodesmis seaweed in experiments that required caging colonies of the branching coral Acropora nasuta and the associated fish species. Only the gobies actively removed algal fronds attached to the cages and only one species (itself toxic to predators) ate them; the damselfish simply defected from the arena when toxic algae were present. The hydrophobic toxins exuded in the algal mucus lysed coral polyps releasing cell constituents that, together with the algal toxin, attract the gobies, which then eat the algal fronds. Interestingly, the toxic goby became more toxic to predators after consumption of the seaweed, which may help to drive symbiosis with a coral colony.

"Recognising ocean acidification in deep time: An evaluation of the evidence for acidification across the Triassic-Jurassic boundary Sarah E. GreeneCorresponding author contact information, 1, E-mail the corresponding author, Rowan C. Martindale1, E-mail the corresponding author, Kathleen A. Ritterbush E-mail the corresponding author, David J. Bottjer E-mail the corresponding author, Frank A. Corsetti E-mail the corresponding author, William M. Berelson E-mail the corresponding author Department of Earth Sciences, University of Southern California, Los Angeles, California, USA 90089 Received 22 July 2011. Accepted 17 March 2012. Available online 5 April 2012. While demonstrating ocean acidification in the modern is relatively straightforward (measure increase in atmospheric CO2 and corresponding ocean chemistry change), identifying palaeo-ocean acidification is problematic. The crux of this problem is that the rock record is a constructive archive while ocean acidification is essentially a destructive (and/or inhibitory) phenomenon. This is exacerbated in deep time without the benefit of a deep ocean record. Here, we discuss the feasibility of, and potential criteria for, identifying an acidification event in deep time. Furthermore, we investigate the evidence for ocean acidification during the Triassic-Jurassic (T-J) boundary interval, an excellent test case because 1) it occurs in deep time, beyond the reach of deep sea drilling coverage; 2) a potential trigger for acidification is known; and 3) it is associated with one of the 'Big Five' mass extinctions which disproportionately affected modern-style invertebrates. Three main criteria suggest that acidification may have occurred across the T-J transition. 1) The eruption of the Central Atlantic Magmatic Province (CAMP) and the associated massive and rapid release of CO2 coincident with the end-Triassic mass extinction provide a suitable trigger for an acidification event (

Abstract Changes in the upwelling and degassing of carbon from the Southern Ocean form one of the leading hypotheses for the cause of glacial-interglacial changes in atmospheric carbon dioxide. We present a 25,000-year-long Southern Ocean radiocarbon record reconstructed from deep-sea corals, which shows radiocarbon-depleted waters during the glacial period and through the early deglaciation. This depletion and associated deep stratification disappeared by ~14.6 ka (thousand years ago), consistent with the transfer of carbon from the deep ocean to the surface ocean and atmosphere via a Southern Ocean ventilation event. Given this evidence for carbon exchange in the Southern Ocean, we show that existing deep-ocean radiocarbon records from the glacial period are sufficiently depleted to explain the ~190 per mil drop in atmospheric radiocarbon between ~17 and 14.5 ka.

"Some of the planet's most beautiful and diverse ecosystems are at risk. With temperatures on the rise, coral reefs are at greater risk for coral bleaching. Using ocean observing system data from NOAA's National Data Buoy Center, this classroom activity examines ocean temperatures off Puerto Rico to see how coral reefs are being impacted and predict what's on the horizon. Brought to you by Sea Grant's Bridge website and COSEE-NOW. This activity was developed in response to the 2005 massive coral bleaching event in the Caribbean caused by high sea surface temperatures. Using ocean observing system data, water temperatures can be monitored to evaluate the likeliness of other bleaching events. Via the COSEE-NOW online community, we were able to receive valuable feedback on making the graph of water temperature more user-friendly and expanding the discussion questions to evoke some higher level thinking from students. This activity has been demonstrated to teachers at the National Marine Educators Association conference and Virginia Sea Grant professional development institutes; and to graduate students in several different settings. http://www2.vims.edu/bridge/DATA.cfm?Bridge_Location=archive0406.html"

"What are the impacts of ocean acidification on key benthic (seabed) ecosystems, communities, habitats, species and their life cycles? The average acidity (pH) of the world's oceans has been stable for the last 25 million years. However, the oceans are now absorbing so much man made CO2 from the atmosphere that measurable changes in seawater pH and carbonate chemistry can be seen. It is predicted that this could affect the basic biological functions of many marine organisms. This in turn could have implications for the survival of populations and communities, as well as the maintenance of biodiversity and ecosystem function. In the seas around the UK, the habitats that make up the seafloor, along with the animals associated with them, play a crucial role in maintaining a healthy and productive marine ecosystem. This is important considering 40% of the world's population lives within 100km of the coast and many of these people depend on coastal systems for food, economic prosperity and well-being. Given that coastal habitats also harbour incredibly high levels of biodiversity, any environmental change that affects these important ecosystems could have substantial environmental and economical impacts. During several recent international meetings scientific experts have concluded that new research is urgently needed. In particular we need long-term studies that determine: which organisms are likely to be tolerant to high CO2 and which are vulnerable; whether organisms will have time to adapt or acclimatise to this rapid environmental change; and how the interactions between individuals that determine ecosystem structure will be affected. This current lack of understanding is a major problem as ocean acidification is a rapidly evolving management issue and, with an insufficient knowledge base, policy makers and managers are struggling to formulate effective strategies to sustain and protect the marine environment in the face of ocean acidification."

Produced by: Plastic Debris, Rivers to Sea Project Algalita and California Coastal Commission Funding provided by the State Water Resources Control Board June 2006 pdf document, 91 pages Introduction - The California Marine Debris Action Plan of 1990 - A State Mandate to Eliminate Marine Debris is Necessary - The Plastic Debris, Rivers to Sea Project - The Action Plan - The Actions Recommended in this Plan - Process and Prioritization Part I: Marine Debris - Sources, Composition, and Quantities - What is Marine Debris? - Land versus Ocean Sources - Abundance of Plastic in the Marine Environment - Quantities of Plastic Debris Increasing Significantly in Oceans - Sources and Composition of Debris Found on Beaches - Trash and Debris in Stormwater and Urban Runoff - Other Research Characterizing Trash in Urban Runoff - Distribution and Composition of Marine Debris on California's Coast Part II: Marine Debris - Impacts - Ingestion and Entanglement - Ecosystem Impacts - Debris as a Transport Mechanism for Toxics and Invasive Species - Economic Impacts Part III: Current Efforts to Address Land-Based Discharges of Marine Debris - Federal Programs and Initiatives - State Programs and Initiatives - Regional Programs and Initiatives - Local Government Programs and Initiatives - National Public Interest Groups - California Public Interest Groups and Associations - Industry Initiatives

Welcome to the Otter Spotter Blog! Otter Spotter is a collaborative project for the Seneca Park Zoo, Association of Zoos and Aquariums (AZA), and the Rochester Institute of Technology (RIT). Content is complied by Emily Coon-Frisch who currently works as the On-Site Education Coordinator at the Seneca Park Zoo, serves as a Education Advisor for the AZA's Otter Species Survival Committee, and is graduate student at RIT.

"The theme of the 175th Annual Meeting of the American Association for the Advancement of Science (AAAS), "Our Planet and Its Life, Origins, and Futures," celebrated an enormous breadth of scientific accomplishments that transcends many subdisciplines of the natural and social sciences. It was intended to be both a reflection on what has been learned and a look forward to what must yet be better known if we are to make wise choices as stewards of our planet. The program committee saw this as an opportunity to examine how we have come to know and understand the coevolution of life with its interacting biological, biogeochemical, and physical environments. Further advances in this area are essential to develop scenarios that can be useful in guiding decisions to address some of society's most pressing problems. We must work toward a future that embraces the wise application of science to improve human health and well-being and to sustain the great diversity of life on our planet. "

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