Dispatches

The Hyperspectral Imager for the Coastal Ocean (HICO), currently orbiting Earth on the International Space Station (ISS), uses an innovative technique to take spectrally detailed photos. These allow scientists to discern water clarity, depth, bathymetry, organic matter (eg phytoplankton), sediment load, and other features at sites along the world's coasts and in other small water bodies traditionally too complex to monitor from space. Although color satellite images have long been used to provide information about the open oceans, this new method represents a vast improvement in the way that more optically complicated areas, such as coastal waterways and small estuaries, are monitored. Daniel Korwan, a research physicist at the US Naval Research Laboratory (Washington, DC) and one of the developers of HICO, explains: “HICO images Earth from the ISS as often as once every 100-minute orbit. Unlike a normal camera's pixels, where each is made up of red, green, and blue, the HICO pixel represents a full spectrum of color shades, including those just beyond visible light into the infrared. Based on the spectral surface reflectance, the images allow us to separate the various constituents in the water and on the ocean floor. In this way, HICO can be used to monitor coastal changes like red tides and agricultural run-off.” HICO image of Pensacola Bay, FL. Since HICO was placed on the ISS in September 2009, the data it has collected have been used in a wide variety of projects focused on improving coastal ocean health. Blake Schaeffer, a research ecologist with the US Environmental Protection Agency (Gulf Breeze, FL), says, “Sensors like HICO can provide monitoring capabilities [that] could inform local stakeholders of responses to best management practices. These data are useful for decision support since they provide broad spatial and temporal coverage – more than that available through traditional sampling.” And it's not just scientists and decision makers who will benefit from this revolutionary instrument. Using data from HICO, Schaeffer and his team have created a prototype smartphone application that is currently under review and should soon be available to the general public. Schaeffer continues, “most citizens are very aware of the atmospheric conditions in their locality due to daily reporting on local and national news stations. However, the same is not true regarding water quality conditions. Our hope is that this mobile application will be one of many different tools that may increase awareness of water quality and ecosystem health.” New research has found high levels of caffeine in the coastal waters of the US state of Oregon. Interestingly, the highest concentrations weren't detected in samples collected near large population centers or wastewater treatment plants, but rather in those obtained close to remote state parks along the state's northern coast, according to findings published in the July issue of Marine Pollution Bulletin (2012; doi:10.1016/j.marpolbul.2012. 04.015). But overly caffeinated campers aren't necessarily to blame. The timing of sample collections may be key; because the samples were collected along the northern Oregon coast on April 3, 2010, one day after an unusual late-season storm, they may have captured a flush of contaminants from overloaded sewage treatment sources. The researchers suggest that the storm caused the region's combined sewer systems – those collecting stormwater along with untreated human and industrial waste – as well as septic tanks used at the state parks to overflow, resulting in high caffeine inputs into the ocean. “It's not that caffeine is necessarily entering the ocean daily in Oregon”, comments study author Elise Granek, an environmental scientist at Portland State University (Portland, OR). Caffeine is increasingly considered to be an ideal marker of human-caused pollution. “Caffeine is something everybody uses and is an easily measured, effective tracer of poorly treated sewage”, explains Patrick Phillips, a hydrologist with the US Geological Survey (Troy, NY). Other contaminants – for example hormones or pharmaceuticals – that have known biological impacts are often more difficult to measure. What's not yet clear is whether caffeine itself affects wildlife. A paper published by Granek and colleagues last year (Ecotoxicology 2011; doi:10.1007/s10646-011-0649-6) demonstrated that the gill tissue of mussels (Mytilus californianus) exposed to 0.05–0.2 μg of caffeine per liter of seawater had increased production of Hsp70, a heat shock protein considered to be an indicator of cellular stress. Although some studies have documented caffeine levels in freshwater systems around the US, Granek's is the first to sample marine coastal waters. The research will, in part, help coastal managers identify land-based impacts as they prioritize future site additions to Oregon's network of marine reserves. As the growing burden of atmospheric CO2 turns ocean waters increasingly acidic, scientists are striving to understand how species and ecosystems will respond. Laboratory research has revealed wide-ranging effects on sea life, including changes in photosynthesis, calcification, respiration, and metabolic rates, but “real-world” studies on marine organisms in the open ocean have proven devilishly difficult to implement. Now, a novel system for simulating future seawater conditions is offering researchers opportunities to more realistically gauge the repercussions of ocean acidification. Along the US West Coast, acidification has caused massive kills of shellfish larvae, and a recent report projects that, within 30 years, levels of aragonite – calcium carbonate needed for myriad organisms to build skeletons and shells – will decline precipitously in nearshore habitats. At the Monterey Bay Aquarium Research Institute (MBARI, Moss Landing, CA), chemist Peter Brewer and colleagues have spent 6 years engineering a complex apparatus for conducting Free-Ocean Carbon dioxide Enrichment (FOCE) experiments. Simply put, the system consists of a semi-enclosed chamber containing study organisms that rests on a patch of ocean floor. Liquid CO2, pumped into the chamber to lower seawater pH, is controlled by sensors to maintain a precise level of acidity, and cameras monitor the effects on marine biota. The system passed scientific trials in late 2011. In Australia, where coral samples from the Great Barrier Reef show a 14% decrease in calcification over the past two decades, David Kline, formerly at the University of Queensland (Brisbane, Australia) and now at Scripps Institution of Oceanography (San Diego, CA), learned about FOCE during its development. He collaborated with the MBARI team to design a model suitable for shallow-water coral reef environments and used it in a 2009 study. The results revealed that – over a 3-day period – calcification declined in reef-forming coralline algae at pH levels predicted for 2050 (Nat Sci Rep 2012; doi:10.1038/srep00413). “FOCE represents a major breakthrough in ocean acidification research”, says Kline, “providing the ability to do in situ experiments under tightly controlled chemistry conditions in natural seawater and with a full community of organisms. It will allow us to study interactive processes and hopefully give us a better understanding of impacts on ecosystems instead of just single species.” MBARI engineer Bill Kirkwood confirms that a generic “x-FOCE” design, employing open-source software and hardware, will soon be made available to the research community. Plans for installations off the coasts of California, France, the UK, and Antarctica are currently in development. TRAFFIC, a non-governmental organization that monitors international trade in wildlife, has placed the Solomon Islands at the center of a scandal in which thousands of wild-caught CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora)-listed birds have been exported as “captive-bred”, thereby circumventing strict rules governing their trade. The report, The Export and Re-export of CITES-listed Birds from the Solomon Islands (www.traffic.org/speciesreports/traffic_species_birds17.pdf), shows that approximately 68 000 birds were exported from the Islands between 2000 and 2010. Of the 54 793 individuals that belonged to native species, 41 101 were declared captive-bred. The non-native birds (mostly species from Indonesia and Papua New Guinea) were nearly all declared captive-bred (13 736), yet no records exist for any breeding stock being imported into the Islands. Rainbow lorikeets are part of the Solomon Islands' illicit bird trade. Captive breeding on this scale would require large facilities, but a 2006 CITES report declared that the Islands lack such amenities. Indeed, the Environment Conservation Division of the Solomon Islands Ministry of Environment Conservation and Meteorology has declared that only holding facilities exist, and that most of these exported birds were, in fact, wild-caught. Although the Solomon Islands officially suspended trade in its wildlife in 2006, “breeders” were allowed to run down their existing stocks. While the numbers of birds involved dramatically declined, many traffickers were able to carry on rebranding their wild-caught birds and continue their illicit trade. “Declaring exported birds as being captive-bred has all the hallmarks of a scam to get around international trade regulations”, said the report's co-author Chris Shepard (Deputy Regional Director TRAFFIC South East Asia, Petaling Jaya, Malaysia). Malaysia, one of the largest importers of these birds, has now suspended all such trade with the Solomon Islands. The TRAFFIC report urges other importing nations, particularly Singapore, to follow suit. It also requests that CITES pursue a full investigation and consider suspending trade in all CITES-listed species from the Islands if any ensuing recommendations are not met. “The Solomon Islands [are] a major supplier to the international wildlife trade and a global biodiversity hot-spot”, says Katherine Smith (Brown University, Providence, RI). “The country exports myriad species, including corals and reptiles, under the declaration ‘captive-bred’. CITES should look beyond birds and investigate the legitimacy of all its wildlife exports.” It pays to be green. A new study shows that energy-efficiency certifications boost California house prices by nearly 10%. Residential homes account for 15% of US energy consumption, and greenhouse gases emitted from the average house can be double those from a car, according to the US Energy Star program. Green-certified homes, however, can cut energy use by more than one-third. The study, The Value of Green Labels in the California Housing Market, released in July 2012 by University of California (UC) economists, compared sales prices of green-labeled (Energy Star, LEED, and Green-point Rated) houses in California with those of non-certified houses that were otherwise similar in age, location, size, and other factors. The mean price increase of $35 000 far outweighed the extra costs of green construction (up to $10 000 for the average house), showing that builders can do well by doing good. Do solar panels make people happier? “The market will reward builders and property owners who make the right decision”, says Karen Kho, program manager at Alameda County's StopWaste.org (Oakland, CA), which helped fund the study. Nationwide, 17% of new home construction was green in 2011, according to McGraw-Hill Construction, which analyzes building industry trends. The premium for green homes likely exceeds the long-term energy bill savings to homeowners. At current energy prices, it would take nearly 50 years just to break even. “The question is, why?”, asks David Lehrer, co-director of the UC Berkeley Green Building Research Center, Berkeley, CA. “Is it for health or because they want to do the right thing?” It's probably a mix of both. Green buildings have cleaner air and more stable temperatures, making them more comfortable for occupants. The new study showed that environmental beliefs are also a factor. Green homes sold for particularly high prices in neighborhoods with a lot of hybrid cars, which was dubbed the “Prius effect” by the researchers, Nils Kok of UC Berkeley and Maastricht University (Maastricht, The Netherlands) and Matthew Kahn of UC Los Angeles. “A lot of this is about perception”, agrees Lehrer. “People think they will be happier in that environment.” Kok and Kahn call for rating all homes by energy efficiency – not just those that are green – to drive overall residential energy conservation. Homes in the European Union are rated by thermal efficiency and, in a 2011 study, Kok found that top-rated Dutch homes fetched above-average prices while low-rated homes sold at a discount. Mistletoes, a parasitic group of plants, are actually keystone species and confer many benefits for biodiversity, according to a new study. David Watson, an associate professor in ecology at Charles Sturt University (Albury, Australia), removed all mistletoe plants (primarily Amyema miquelii) from 17 forest patches in the upper Billabong Creek catchment in southeastern New South Wales, Australia. After 3 years, Watson compared biodiversity in these patches with 11 control forest patches and 12 additional woodlands in which mistletoe was naturally absent. “We found a huge direct effect of mistletoe on diversity”, he says. The mistletoebird (Dicaeum hirundinaceum), which, as its name implies, feeds on mistletoe, went locally extinct in four patches and decreased in another two, while at the same time it became more common in the control forests. Even more striking was the effect of removal on other species. The patches where mistletoe was removed lost 20% of their total species and 34.8% of woodland-dependent species. “It's not through the birds that eat [mistletoe] or the species that nest in it”, explains Watson. Rather, mistletoe's leaf litter is a huge boon to insects on the forest floor, and these are food for insectivores; thus, the presence of mistletoe enhances the food web from the bottom up. Nor is it simply mistletoe “slurping up dissolved nutrients from the host plant and redistributing it”, adds Watson. The birds that visit mistletoe to feed or nest also enrich the soil with nutrients taken from kilometers away. “You'd walk around where there were just a few mistletoe plants and not only were there more beasties, but they were all hanging around the infected trees.” The results of the study were published online in July (P R Soc B 2012; doi:10.1098/ rspb.2012.0856). “It was striking, when walking around in these woodlands”, recalls Watson. “What used to be crunchy and spongy underfoot became dry.” Perhaps even more noticeable was that mistletoe made up just 3% of the total volume of plants in a given forest; at one site, Watson only needed to remove ten mistletoe plants to locally extirpate the species. Although it caused a temporary decline in bird species richness, Watson hopes his research will lead to long-term positive results for Australia's woodlands. “Parasites have this really bad [reputation]. Many local councils have it on the books that removing mistletoe is part of normal tree maintenance. This work demonstrates that mistletoe promotes diversity, benefiting all sorts of critters. The same councils spending money on mistletoe removal are also paying for reforestation.” Most people have never been to the Arctic and aren't troubled that anthropogenic CO2 emissions produced by their activities are helping to melt the polar ice sheets, but they do care about clean air. Because black carbon (often referred to as soot) and other short-lived air pollutants are responsible for 40–45% of atmospheric warming, scientists hope that tackling air pollution will kickstart an effective campaign for mitigating climate change. “We're stuck in terms of reducing CO2 and meanwhile the climate is warming”, says Veerabhadran Ramanathan, an atmospheric scientist at the Scripps Institution of Oceanography (La Jolla, CA). But national-level governments have experience in cutting air pollution, which provides local benefits, he says. The idea caught on with world leaders in February when the US, Canada, Sweden, Mexico, Ghana, Bangladesh, and the UN Environment Programme (UNEP) launched the Climate and Clean Air Coalition to Reduce Short-Lived Climate Pollutants (CCAC). In July, seven more countries signed on, bringing total current membership to 21. The CACC targets three air pollutants – black carbon, methane, and hydrofluorocarbons (HFCs) – with atmospheric residence times that are less than 15 years; this means that they can be eliminated much faster than CO2. Black carbon produced by burning fossil fuels and biomass causes warming because the resulting airborne particles absorb sunlight. Methane, a potent greenhouse gas, also helps to form ground-level ozone that is harmful to both humans and crops. HFCs, refrigerants that replaced stratospheric ozone-destroying chlorofluorocarbons, have 11 000 times the warming potential of CO2. With US$16.7 million in the bank, the coalition plans to work with other global initiatives to reduce methane emissions from landfills and petroleum and natural gas operations, help UNEP clean up black carbon emissions from heavy-duty diesel vehicles, assist countries to improve the efficiency of brick kilns, and catalyze public awareness of HFC risks. The CACC predicts that fully implementing these measures could save 2.5 million lives annually, decrease agricultural losses by 30 million metric tons per year, and slow atmospheric warming by 0.5°C by 2050. “But this isn't a way of buying time because if we don't address CO2, we'll lose the benefits of cutting short-lived pollutants”, warns a research with the Environment Institute of hope that when people that climate such as cutting air benefit human it will them to on adds species to has been found on an in in on the and is the species in two explains who that climate may be the species to its Most of the approximately 30 species found in northern are species of the – that have these species, explains are soil litter and and we would have predicted that all the for were making it that an species would to their however, and a at that were on the of the normal 2012; and the by the the researchers stable in tissue samples collected from “The were the carbon and that were to native explains this to its northern European it may carbon from the soil that would otherwise up if only native species were However, there are a lot of in this and the may just into the existing report is in two comments soil ecologist Patrick of “It a that could be to climate and shows that the species has a to the other species at the site, that this new species could have a novel effect on the of soil carbon and organic the may local ecosystems in its new home is currently says but an for future it to naturally at a lower Although is an for in and the A new carbon by scientists at State University research on emissions from with the Carbon which for in – the form of created by the to be in carbon for more by more or by new to improve says lead an ecosystem ecologist The carbon by through can be sold on the market for The is a for both and the “The uses an innovative to to less in a way that not explains an and costs to carbon benefit from and a reward for more management And less to agricultural means less lost to the The in the study the effects of different application by the – a carbon – is a huge for the is the first time that a from research and published in the has been for use in the carbon says However, the many in implementing that the is used to reduce will on the of to which in will on of use and the price of the first – the is and to – but the price of carbon is up to the for carbon species for on the a recent study may light on their In the first of the nearly known bird species native to New researchers have demonstrated how have four time (P R Soc B 2012; The the first three and by the of and in New in and during the the period and species. 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