News Article | April 17, 2017
Debris from logging in tropical forests is threatening the survival of hatchling leatherback turtles and the success of mothers at one of the world's most important nesting sites in Colombia. New research by the University of Exeter and the Doñana Biological Station in Seville, Spain, has found that debris on beaches caused by logging activity is impacting both young turtles and their mothers during the key periods of their life cycles. Leatherbacks are at particular risk of being caught up in fishing nets and longlines as bycatch, because they are migratory, travelling long distances worldwide. Many breeding sites are already under pressure from tourism. But now, research published in the journal Marine Ecology Progress Series has revealed that the logging is an additional, previously underestimated threat. To nest and breed successfully, females must be able to cross the sandy beaches to dig their nest to successfully incubate their eggs. In turn, hatchlings must be able to cross the sand unaccompanied to reach the water. Researchers found that the beach debris hindered this movement. The team monitored 216 turtles, comparing their activity in areas with high amounts of debris to low amounts, in a globally significant nesting site in Colombia. They also manipulated the amount of debris to see how it changed behaviour. They found that females which nested in areas with higher amounts of debris were spent more time building their nest and tended to do so closer to the shoreline. This meant they were more vulnerable to flooding, which puts their eggs at risk. Some females were even wounded in the process. The debris also meant it took longer for hatchlings to reach the sea, increasing their chance of being eaten by predators and meaning they had to expend more energy, making them more vulnerable. Professor Brendan Godley, director of the Centre for Ecology and Conservation on the University of Exeter's Penryn Campus in Cornwall, is a co-author on the research. He said: "Leatherback turtles are already under immense pressure, from fisheries bycatch and are also one of the species prone to ingesting marine plastic litter. "Our research clearly indicates that logging presents another threat. "It is now paramount that beach clean-up operations are built into logging activities to prevent further damage to this species." Dr Adolfo Marco Llorente, of the Doñana Biological Station, said: "Although logging debris does not affect rates of nesting, it has a significant impact on where and how nests are built, which negatively affects both mothers and hatchlings. "This is on a scale that could lead over time to reduction of the overall population. "Simple measures could make a real difference, such as repositioning organic waste areas, or salvaging the wood debris as an energy source. "It's also essential that logging practices that reduce the impact on the marine environment are implemented."
News Article | May 3, 2017
While this partially-bleached coral isn't handling warm water too well, new research has found that some species are adapting to an increase in temperature (Credit: Tim McClanahan/WCS) Rising ocean temperatures are wreaking havoc on the organisms that live there, and one only needs to look to coral reefs to see the extent of the damage. Severe coral bleaching events could become increasingly regular, but a new study has revealed a glimmer of hope. Some species of coral – but by no means, all of them – appear to be adapting to the warming waters, with researchers finding less bleached coral in a 2016 event than under similar circumstances in 1998. Last year was a bad year for coral. Unusually warm water puts a lot of stress on the organisms, and in response they discharge vital algae, which robs them of nutrients and color. The resulting paleness, known as bleaching, paints a pretty clear picture of an ailing reef, and reports suggest the condition affected about 60 percent of the world's coral in 2016, including huge swathes of Australia's Great Barrier Reef. While there are indications that these kinds of events might become more regular in the near future, a new study by the Wildlife Conservation Society has found some good news among the bad. Examining two marine national parks in Kenya, which were among those affected in last year's bleaching event, the researchers found a significant decline in the number of bleached coral colonies, when compared to a similar event in 1998. Out of 21 coral species studied, 11 appeared to be hardier against bleaching than they were 20 years ago. In one park, the number of bleached coral colonies dropped from 73 percent in 1998 to just 27 percent in 2016, while the other park fell from 96 to 60 percent. Encouraging as that sounds, the rest of the species studied weren't handling the changes well, with one seeming more vulnerable to bleaching now than in the past. "This was a rare chance to study bleaching responses during two separate times with very similar conditions," says Tim McClanahan, author of the study. "Adaptation is evident for some of the more important reef building corals but, sadly, many species are not adapting, so this is a good news-bad news story. Evidence for adaptation in the past is not evidence for adaptation in the future. Nevertheless, I suspect this adaptation to hot water started before my 1998 work and could have begun during the 1983 and 1988 El Niños, when coral bleaching was first observed in the region." The research was published in the journal Marine Ecology Progress Series.
News Article | March 16, 2017
After completing a 10-year observation project on the northern coast of British Columbia, researchers have discovered a never-seen-before pattern in the whales's behavior. Humpback whales typically spend their summer in this region, hunting and feeding in the cold waters of the Kitimat fjord, following their winter migration to the South. Their arrival in the fjord — located in the vicinity of Hartley Bay — occurs every year, since this area offers an abundance of prey, but scientists now uncovered there's a method to it. In the span of a decade, marine biologists from Gitga'at First Nation and the North Coast Cetacean Society were able to observe the humpbacks follow a distinct pattern in their voyage to Kitimat. At first, the whales spend some time in the outer waters of the fjord, after which they start moving closer to the inlet and the Douglas Channel — and they do this each year, without exception. The researchers who studied this behavior call it a "whale wave" and published their observations in the journal Marine Ecology Progress Series. "The peak of the wave moves progressively inland," said study author Chris Picard, a science director at Gitga'at First Nation. The seasonal pattern identified in the humpbacks's annual journey to Kitimat has prompted discussions for new conservation strategies in the area. Canadian scientists are concerned that the prospective development of an oil pipeline through Douglas Channel would deeply affect the whales's migratory habits, and believe all efforts must be made to preserve their habitat. Although it's not yet clear why the humpbacks choose to move so close to the inlet, Picard is hopeful his research will persuade authorities to leave the area intact. "Understanding these details, we think, can lead to better conservation, and lead to better management of any activities that could potentially disrupt any part of that habitat," he explains. According to Picard, "habitats are not interchangeable," therefore humpback whales wouldn't have anywhere else to go if their Gitga'at territory was damaged or taken over for the purpose of technological exploits. In the interest of conservation, Picard's team tried to determine what draws the humpbacks so close to Douglas Channel. His study indicated that, although the creatures clearly come to this area to feed, the mysterious "whale wave" may be more connected with their social behavior. Observations revealed that, upon reaching the inlet, the whales primarily engage in social interactions, calling and singing to each other, and focus less on hunting. Picard suggests they could be practicing their mating calls for the winter. © 2017 Tech Times, All rights reserved. Do not reproduce without permission.
News Article | September 7, 2016
On the dock in Buenaventura, Colombia, the fisherman needed help identifying his catch. “I don’t have any clue what this is,” he said, holding a roughly 50-centimeter-long, grayish-brown fish. Gustavo Castellanos-Galindo, a fish ecologist, recalls the conversation from last October. “I said, ‘Well, this is a cobia, and it shouldn’t be here.’ ” The juvenile cobia had probably escaped from a farm off the coast of Ecuador that began operating earlier in 2015, Castellanos-Galindo and colleagues at the World Wildlife Fund in Cali, Colombia, reported in March in BioInvasions Records. Intruders had probably cut a net cage, perhaps intending to catch and sell the fish. Roughly 1,500 cobia fled, according to the aquaculture company Ocean Farm in Manta, Ecuador, which runs the farm. Cobia are fast-swimming predators that can migrate long distances and grow to about 2 meters long. The species is not native to the eastern Pacific, but since the escape, the fugitives have been spotted from Panama to Peru. The cobia getaway is not an isolated incident. Aquaculture, the farming of fish and other aquatic species, is rapidly expanding — both in marine and inland farms. It has begun to overtake wild-catch fishing as the main source of seafood for the dinner table. Fish farmed in the ocean, such as salmon, sea bass, sea bream and other species, are raised in giant offshore pens that can be breached by storms, predators, fish that nibble the nets, employee error and thieves. Global numbers for escapes are hard to come by, but one study of six European countries over three years found that nearly 9 million fish escaped from sea cages, according to a report published in Aquaculture in 2015. Researchers worry that these releases could harm wildlife, but they don’t have a lot of data to measure long-term effects. Many questions remain. A study out of Norway published in July suggests that some domesticated escapees have mated extensively with wild fish of the same species, which could weaken the wild population. Scientists also are investigating whether escaped fish could gobble up or displace native fish. Worst-case scenario: Escaped fish spread over large areas and wreak havoc on other species. From toxic toads overrunning Australia and Madagascar (SN Online: 2/22/16) to red imported fire ants in the United States, invasive species are one of the planet’s biggest threats to biodiversity, and they cost billions of dollars in damage and management expenses. Not every introduced species has such drastic effects, but invasives can be tough to eliminate. While researchers try to get a handle on the impact of farm escapes, farmers are working to better contain the fish and reduce the ecological impact of the runaways. Some countries have tightened their aquaculture regulations. Researchers are proposing strategies ranging from new farm designs to altering fish genetics. As aquaculture becomes a widespread means to feed the planet’s protein-hungry people, the ecological effects are getting more attention. If escapees weaken native wildlife, “we’re solving a food issue globally and creating another problem,” says population geneticist Kevin Glover of Norway’s Institute of Marine Research in Bergen. Norway, a top producer of marine fish, has done much of the research on farm escapes. Fish farming is big business. In 2014, the industry churned out 73.8 million metric tons of aquatic animals worth about $160 billion, according to a report in July from the Food and Agriculture Organization of the United Nations in Rome. Nearly two-thirds of this food comes from inland freshwater farms such as ponds, used in Asia for thousands of years. The rest is grown on marine and coastal farms, where farmed fish live in brackish ponds, lagoons or cages in the ocean. Freshwater fish can escape from pond farms during events such as floods. Some escapees, such as tilapia, have hurt native species by competing with and eating wild fish. But sea farming has its own set of problems. The physical environment is harsh and cages are exposed to damaging ocean waves and wind, plus boats and predator attacks. Salmon is one of the most heavily farmed marine fish. In some areas, the number of farmed salmon dwarfs wild populations. Norway’s marine farms hold about 380 million Atlantic salmon, while the country’s rivers are home to only about 500,000 wild spawning Atlantic salmon. In the four decades that farmers have been cultivating Atlantic salmon, farmed strains have diverged from their wild cousins. When both are raised in standard hatchery conditions, farm-raised salmon can grow about three to five times heavier than wild salmon in the first year of life. Salmon raised in farms also tend to be less careful; for instance, after being exposed to an artificial predator, they emerge more quickly from hiding places than wild fish. This risky behavior may have arisen partly because the fish haven’t faced the harsh challenges of nature. “The whole idea of a hatchery is that everything gets to survive,” says Philip McGinnity, a molecular ecologist at University College Cork in Ireland. Farmed fish don’t know better. These differences are bad news for hybrid offspring and wild fish. In early experiments, hybrid offspring of farmed and wild salmon tended to fare poorly in the wild. In the 1990s, McGinnity’s team measured these fish’s “lifetime success” in spawning rivers and the ocean. Compared with wild salmon, hybrid offspring had a lifetime success rate about a fourth to a half as high. Around the same time, a team in Norway found that when wild fish swam with farmed fish in their midst, the number of wild offspring that survived long enough to leave the river to head to the ocean was about one-third lower than expected, perhaps because the fast-growing farmed offspring gobbled a lot of food or claimed territory. “There was truly reason to be concerned,” says Ian Fleming, an evolutionary ecologist at Memorial University of Newfoundland in St. John’s, Canada, who was part of the Norway team. Recent work supports the idea that farmed fish could crowd out wild fish by hogging territory in a river. In a study published last year in the Journal of Fish Biology, researchers found that the survival rate of young wild salmon dropped from 74 to 53 percent when the fish were raised in the same confined stream channels as young farmed salmon rather than on their own. When the channels had an exit, more wild fish departed the stream when raised with farmed salmon than when raised alone. “These are fish that give up the territory and have to leave,” says study coauthor Kjetil Hindar, a salmon biologist at the Norwegian Institute for Nature Research in Trondheim. To find out how much escaped fish had genetically mingled with wild fish, Glover’s team obtained historical samples of salmon scales collected from 20 rivers in Norway before aquaculture became common. The researchers compared the DNA in the scales with that of wild salmon caught from 2001 to 2010 in those rivers. Wild salmon in five of the 20 rivers had become more genetically similar to farmed fish over about one to four decades, the team reported in 2013 in BMC Genetics. In the most affected population, 47 percent of the wild fish’s genome originated from farmed strains. “We’re talking about more or less a complete swamping of the natural gene pool,” Glover says. Imagine buckets of paint — red, blue, green — representing each river, he says, and pouring gray paint into each one. Interbreeding was less of an issue where wild fish were plentiful. The farmed fish aren’t good at spawning, so they won’t mate much if a lot of wild competitors are present. But in sparse populations, the farm-raised salmon may be able to “muscle in,” Glover says. A larger study by Hindar’s team, published in July in the ICES Journal of Marine Science, showed that genetic mixing between wild and farmed salmon is happening on a large scale in Norway. Among 109 wild salmon populations, about half had significant amounts of genetic material from farmed strains that had escaped. In 27 populations, more than 10 percent of the fish’s DNA came from farmed fish. What does that mean for the offspring? Each salmon population has adapted to survive in its habitat — a certain river, at a specific temperature range or acidity level. When farmed fish mate with wild fish, the resulting offspring may not be as well-suited to live in that environment. Over generations, as the wild population becomes more similar to farmed salmon, scientists worry that the fish’s survival could drop. Scientists at several institutions in Norway are exploring whether genetic mixing changes the wild salmon’s survival rates, growth and other traits. Making a definitive link will be difficult. Other threats such as climate change and pollution also are putting stress on the fish. If escapes can be stopped, wild salmon may rebound. Natural selection will weed out the weakest fish and leave the strongest, fish that got a lucky combination of hardy traits from their parents. But Glover worries that, just as a beach can’t recover if oil is spilled every year, the wild population can’t rally if farmed fish are continually pumped in: “Mother Nature cannot clean up if you constantly pollute.” In places where the species being farmed is not naturally abundant, researchers are taking a look at whether escapes could upset native ecosystems. For instance, European sea bass sometimes slip away from farms in the Canary Islands, where (except for a few small populations on the eastern end) the species doesn’t normally live. In February 2010, storms battered cages at the island of La Palma, “like a giant tore up all the nets,” says Kilian Toledo-Guedes, a marine ecologist at the University of Alicante in Spain. About 1.5 million fish — mostly sea bass — reportedly swam free. A couple of weeks later, the number of sea bass in nearby waters was “astounding,” he says. “I couldn’t see the bottom.” Sea bass density in waters near the farm was 162 times higher than it had been at the same time the previous year, his team reported in 2014 in Fisheries Management and Ecology. Fisheries data showing a spike in catches of sea bass by local fishermen that January also suggested that large unreported escapes had occurred before the storm. Despite being raised in captivity, where they are fed pellets, some of the farmed fish learn to hunt. The researchers found that escaped sea bass caught four months after the 2010 farm breakdown had eaten mostly crabs. Sea bass from earlier escapes that had been living in the wild for several years had eaten plenty of fish as well. The results, reported in 2014 in Marine Environmental Research, suggest that escapees start by catching easy targets such as crustaceans and then learn to nab faster-moving fish. So far, though, scientists have not seen clear signs that the escapees damaged the ecosystem. The density of sea bass around La Palma had fallen drastically by October 2010 and continued to decline the next year, probably because some fish couldn’t find enough to eat, while others were caught by fishermen or predators, according to a 2015 study by another team in the Journal of Aquaculture Research & Development. Catches of small fish that sea bass eat, such as parrot fish, did not drop significantly after the 2010 escape or after a similar large escape in 1999, says study coauthor Ricardo Haroun, a marine conservation researcher at the University of Las Palmas de Gran Canaria in Spain. While he agrees that the industry should try to prevent escapes, he sees no evidence that the runaways are suppressing wild species. If the escaped fish can breed and multiply, the risk of harming native species rises. In a study published in Marine Ecology in 2012, Toledo-Guedes and colleagues reported finding sexually mature sea bass around the central island of Tenerife. But Haroun says the water is too warm and salty for the fish to reproduce, and his team did not see any juveniles during their surveys of La Palma, nor have they heard any reports of juveniles in the area. Toledo-Guedes says that more extensive studies, such as efforts to catch larvae, are needed before reproduction can be ruled out. Similarly, researchers can’t predict the consequences of the cobia escape in Ecuador. The water is the right temperature for reproduction, and these predators eat everything from crabs to squid. Castellanos-Galindo believes that farming cobia in the area is a mistake because escapes will probably continue, and the fish may eventually form a stable population in the wild that could have unpredictable effects on native prey and other parts of the ecosystem. He points to invasive lionfish as a cautionary tale: These predators, probably released from personal aquariums in Florida, have exploded across the Caribbean, Gulf of Mexico and western Atlantic and are devouring small reef fish. The situation for cobia may be different. Local sharks and other predators will probably eat the escapees, whereas lionfish have few natural predators in their new territory, argues Diego Ardila, production manager at Ocean Farm. Milton Love, a marine fish ecologist at the University of California, Santa Barbara, also notes that lionfish settle in one small area, but cobia keep moving, so prey populations might recover after the cobia have moved on. Not all introduced species become established or invasive, and it can take decades for the effects to become apparent. “Time will tell what happens,” says Andrew Sellers, a marine ecologist at the Smithsonian Tropical Research Institute in Panama City. “Basically, it’s just up to the fish.” Once fish have fled, farmers sometimes enlist fishermen to help capture the escapees. Professional fishermen caught nearly one-quarter of the sea bass and sea bream that escaped after the Canary Islands breach. On average, though, only 8 percent of fish are recaptured after an escape, according to a study published in June in Reviews in Aquaculture. Given the recapture failures, farmers and policy makers should focus on preventing escapes and maintaining no-fishing zones around farms to create a “wall of mouths,” local predators that can eat runaway fish, says coauthor Tim Dempster, a sustainable aquaculture researcher at the University of Melbourne in Australia. Technical improvements could help. The Norwegian government rolled out a marine aquaculture standard in 2004 that required improvements, such as engineering nets, moorings and other equipment to withstand unusually strong storms. Compared with the period 2001–2006, the average number of Atlantic salmon escaping annually from 2007–2009 dropped by more than half. Ocean Farm in Ecuador has tightened security, increased cage inspections and switched to stronger net materials; no cobia have escaped since last year’s break-in, says Samir Kuri, the company’s operations manager. Some companies raise fish in contained tanks on land to avoid polluting marine waters, reduce exposure to diseases and control growth conditions. But the industry is largely reluctant to adopt this option until costs come down. The money saved from reducing escapes probably wouldn’t make up for the current start-up expense of moving to land. The 242 escape events analyzed in the 2015 Aquaculture study cost farmers about $160 million. By one estimate, establishing a land-based closed-containment farm producing about 4,000 metric tons of salmon annually — a small haul by industry standards — would cost $54 million; setting up a similar-sized sea-cage farm costs $30 million. Another solution is to raise fish that have three sets of chromosomes. These triploid fish, produced by subjecting fertilized eggs to a pressure shock, can’t reproduce and therefore wouldn’t proliferate or pollute the wild gene pool. “The only ultimate solution is sterility,” Norway’s Glover says. “Accidents happen.” Escaped triploid salmon are less likely to disrupt mating by distracting females from wild males, the researchers wrote in Biological Invasions in May. But triploid fish don’t grow as well when the water is warmer than about 15° Celsius, and consumers might be reluctant to accept these altered salmon. Although the ecological effects of fish farm escapes may take a long time to play out, most researchers agree that we shouldn’t take chances with the health of the oceans, which already face threats such as climate change, pollution and overfishing. With the aquaculture industry expanding at about 6 percent per year, farmers will have to keep improving their practices if they are to stay ahead of the runaway fish. This story appears in the September 17, 2016, issue of Science News with the headline, "Runaway fish: Escapes from marine farms raise concerns about native wildlife."
News Article | December 5, 2016
NEW YORK (November 30, 2016) --A study of complex coral reef ecosystems in the western Indian Ocean found that one species of fish--the orange-lined triggerfish--may play a significant role in maintaining a reef's ability to thrive and grow, according to investigations by WCS (Wildlife Conservation Society). Scientists working for WCS discovered that the orange-lined triggerfish (Balistapus undulatus)--a small but brilliantly colored predatory fish--was consistently found among corals and algae that build reef systems. Triggerfish are known to reduce sea urchin species that degrade reef structure when they become too numerous, and the authors believe this relationship may explain the positive association of these fish species and reef builders. The study titled "Similar impacts of fishing and environmental stress on calcifying organisms in Indian Ocean coral reefs" appears in the most recent edition of Marine Ecology Progress Series. The authors Tim R. McClanahan and Nyawira A. Muthiga studied algae, corals, fish, and sea urchins in more than 200 Indian Ocean reefs and evaluated a number of variables and alternative explanations to come to this conclusion. "Coral reefs are at risk in many parts of the world, so helping them survive by protecting key species could improve chances for persistence," said Dr. McClanahan, lead author of the study. "It seems that maintaining a few orange-lined triggerfish increases the ability of coral reefs to grow because they prey on reef eroding sea urchins. Consequently, a triggerfishes' choice of food indirectly contributes to a reef's ability to grow and stay ahead of rising sea levels." The authors of the study examined nearly 30 variables relating to coral reef health, ranging from sea surface temperature and sunlight penetration data collected by US satellites since the 1980s, to numbers of animals counted while scuba diving down to 20 meters below the surface. According to the statistical results, subtle predator-prey interactions of fish and marine invertebrates were likely to be equal to or more important than the ocean's environment in promoting reef growth. "Given the increasing bad news about hot ocean temperatures degrading reefs, it was heartening to learn that a key predator might compensate for some of the losses in reef growth," Dr. McClanahan added. The research comes in the wake of the global rise of sea surface temperatures and coral bleaching this past year that badly damaged the iconic Great Barrier Reef and other tropical reefs in locations such as Hawai'i and the Florida Keys. Another relevant finding from this study was that historical water temperatures fluctuations were more important than sporadic hot water periods in predicting a reef's potential to grow. Consequently, not all reefs will be affected by the same stresses related to warmer temperatures, and some combination of increased management of less affected reefs and the protection of the orange-lined triggerfish were among the paper's practical recommendations. The authors stressed that correlation is not yet proof of causality, but maintain that protection for triggerfish species, which contribute very little food or income to coastal communities, would not hurt fisheries. "Careful long-term studies of critical marine species such as triggerfish show the importance of understanding ecosystems and protecting species," said Jason Patlis, WCS's Director for Marine Conservation. "The persistence of coral reefs into the future requires good science and it needs to be followed by equally good conservation strategies and actions." This work has been supported by the John D. and Catherine T. MacArthur Foundation, The Tiffany & Co. Foundation, and the Western Indian Ocean Marine Science Association's Marine Science for Management Program. MISSION: WCS saves wildlife and wild places worldwide through science, conservation action, education, and inspiring people to value nature. To achieve our mission, WCS, based at the Bronx Zoo, harnesses the power of its Global Conservation Program in nearly 60 nations and in all the world's oceans and its five wildlife parks in New York City, visited by 4 million people annually. WCS combines its expertise in the field, zoos, and aquarium to achieve its conservation mission. Visit: newsroom.wcs.org Follow: @WCSNewsroom. For more information: 347-840-1242. The John D. and Catherine T. MacArthur Foundation supports creative people, effective institutions, and influential networks building a more just, verdant, and peaceful world. MacArthur is placing a few big bets that truly significant progress is possible on some of the world's most pressing social challenges, including over-incarceration, global climate change, nuclear risk, and significantly increasing capital for the social sector. In addition to the MacArthur Fellows Program, the Foundation continues its historic commitments to the role of journalism in a responsible and responsive democracy; the strength and vitality of our headquarters city, Chicago; and generating new knowledge about critical issues.
News Article | February 15, 2017
The lack of a standardized procedure for collecting data about elusive and hard to find species like the great white shark has to date seriously hampered efforts to manage and protect these animals The lack of a standardized procedure for collecting data about elusive and hard to find species like the great white shark has to date seriously hampered efforts to manage and protect these animals. But now a marine biologist, an applied mathematician and a software developer from Stellenbosch University joined expertise to develop a custom-made software package, called Identifin, which may offer a solution to this problem. Dr Sara Andreotti, a marine biologist in the Department of Botany and Zoology at SU, have collected over 5000 photographic images of the dorsal fins of white sharks along the South African coastline as part of her research on the population structure of South Africa's great white sharks. This is because the trailing edge of the dorsal fin provides a unique trade, analogous to a human fingerprint. Over six years she managed to manually build a database with information on when and where an individual white shark was sighted. In those cases where she was able to collect a biopsy from the shark, the genetic information was linked to its profile. But she was doing all this manually on her personal computer. "I nearly lost my head. I quickly realised that in the long term updating the database was going to consume more and more of my time. That is when I headed over campus to the applied mathematics division and asked for help. I was stunned when they became all excited about my data," she laughs. Prof. Ben Herbst, a specialist in machine learning, and Dr Pieter Holtzhausen, a software engineer then busy with his PhD in Applied Mathematics, were literally overjoyed to be able to work with Dr Andreotti' s data base. Dr Holtzhausen explains: "We used an algorithmic technique called dynamic time-warping to match the fingerprints. With this technique, any data that can be turned into a linear sequence can be analysed. The technique is often used in speech recognition software." The image recognition software they developed, called Identifin, compares a semi-automatically drawn trace of the back edge of the dorsal fin to existing images in the database. The images in the database are then re-arranged and ranked by probability of match. If there is a match, the database photograph in the first position will be the correct one (see multimedia images). However, while working with Michael Meyer, a marine scientist from the Department of Environmental Affairs, and shark conservationist Michael Rutzen from Shark Diving Unlimited, Dr Andreotti realised that the software needed some more tweaking if it were to fit the ideal of sustaining a large database for the long-term monitoring of the white shark population. "The software had to be capable of quickly matching the fin identification of a newly photographed shark with a possible existing match in the database, and to automatically update the sharks' id catalogue. The database also had to be user-friendly and structured in such a way so that different researchers can use it over the long term," she explains. While there is still room for improvement, the success of the first trials boosted their hope that in the near future they will be able to use Identifin to monitor white shark populations on a large scale. "Previously, while at sea, I had to try and memorize which shark is which, to prevent sampling the same individual more than once. Now Identifin can take over. I will only need to download the new photographic identifications from my camera onto a small field laptop and run the software to see if the sharks currently around the boat have been sampled or not. "By knowing which sharks had not been sampled before we can focus the biopsy collections on them. This saves us both time and money when it comes to genetic analysis in the laboratory," she adds. Dr Andreotti says to date the lack of standardization of data collection has been a major limitation to combining datasets of worldwide distributed species: "We hope Identifin will offer a solution for the development of a South African and then global adaptive management plan for great white sharks." The next step is to adapt Identifin for the identification of other large marine species and help other researchers facing the same kind of struggles. Andreotti S, Rutzen M, Wesche PS, O'Connell CP, Meÿer M, Oosthuizen WH, Matthee CA (2014) A novel categorisation system to organize a large photo identification database for white sharks Carcharodon carcharias. African Journal of Marine Science 36:59-67. Available online at http://www. Andreotti S, Heyden S von der, Henriques R, Rutzen M, Meÿer M, Oosthuizen H, Matthee CA (2016) New insights into the evolutionary history of white sharks, Carcharodon carcharias. Journal of Biogeography 43:328-339. Available online at http://onlinelibrary. Andreotti S, Rutzen M, Walt S van der, Heyden S Von der, Henriques R, Meÿer M, Oosthuizen H, Matthee C (2016) An integrated mark-recapture and genetic approach to estimate the population size of white sharks in South Africa. Marine Ecology Progress Series 552:241-253. Available online at http://www.
News Article | February 5, 2016
The study, reported in the journal Scientific Reports published by Nature, found that exposure to sounds that resemble shipping traffic and offshore construction activities results in behavioural responses in certain invertebrate species that live in the marine sediment. These species make a crucial contribution to the seabed ecosystem as their burrowing and bioirrigation activities (how much the organism moves water in and out of the sediment by its actions) are crucial in nutrient recycling and carbon storage. The study showed that some man-made sounds can cause certain species to reduce irrigation and sediment turnover. Such reductions can lead to the formation of compacted sediments that suffer reduced oxygen, potentially becoming anoxic (depleted of dissolved oxygen and a more severe condition of hypoxia), which may have an impact on seabed productivity, sediment biodiversity and also fisheries production. Lead author Martin Solan, Professor in Marine Ecology, said: "Coastal and shelf environments support high levels of biodiversity that are vital in mediating ecosystem processes, but they are also subject to noise associated with increasing levels of offshore human activity. Previous work has almost exclusively focussed on direct physiological or behavioural responses in marine mammals and fish, and has not previously addressed the indirect impacts of sound on ecosystem properties. "Our study provides evidence that exposing coastal environments to anthropogenic sound fields is likely to have much wider ecosystem consequences than are presently understood." The Southampton researchers exposed three species - the langoustine (Nephrops norvegicus), a slim, orange-pink lobster which grows up to 25 cm long, the Manila clam (Ruditapes philippinarum) and the brittlestar (Amphiura filfiformis) ¬- to two different types of underwater sound fields: continuous broadband noise (CBN) that mimics shipping traffic and intermittent broadband noise (IBN) reflecting marine construction activity. The sounds were reproduced in controlled test tanks and experiments were run on one species at a time. For CBN, a recording (one minute duration, continuously looped) of a ship made in the English Channel at a distance of around 100 metres was used'. For IBN, a recording (two minutes duration, continuously looped) of a wind farm in the North Sea at a distance of about 60 metres was used. The results showed that the sounds could alter the way these species behaved when interacting with their environments. With the langoustine, which disturbs the sediment to create burrows in which it lives, the researchers saw a reduction in the depth of sediment redistribution (how much of the surface sediment was overturned into the deeper layers) with exposure to IBN or CBN. Under CBN and IBN there was evidence that bioirrigation increased. The Manila clam, a commercial fishery species in Europe that lives in the sediment and connects to the overlying water through a retractable siphon, reduced its surface activity under CBN, which affected the surface roughness of the sediment. Bioirrigation, which is strongly influenced by clam behaviour and the activity of the siphon, was markedly reduced by CBN and slightly reduced under IBN. However, the sound fields had little impact on the brittlestar. Co-author Dr Chris Hauton, Associate Professor in Invertebrate Ecophysiology and Immune Function, said: "I think these findings raise the prospect that anthropogenic sounds in the marine environment are impacting marine invertebrate species in ways that have not been previously anticipated. The potential effects of anthropogenic noise on ecosystem function, mediated through changes in organism behaviour merits further study as, in the long term, it may identify impacts to the productivity of seabed systems that have, to date, not really been constrained." Tim Leighton, Professor of Ultrasonics and Underwater Acoustics and study co-author, added: "There has been much discussion over the last decade of the extent to which whales, dolphins and fish stocks, might be disturbed by the sounds from shipping, windfarms and their construction, seismic exploration etc. However, one set of ocean denizens has until now been ignored, and unlike these other classes, they cannot easily move away from loud man-made sound sources. These are the bottom feeders, such as crabs, shellfish and invertebrates similar to the ones in our study, which are crucial to healthy and commercially successful oceans because they form the bottom of the food chain." More information: Anthropogenic sources of underwater sound can modify how sediment-dwelling invertebrates mediate ecosystem properties, Scientific Reports, dx.doi.org/10.1038/srep20540
News Article | January 13, 2016
After posting our early edition of 2016 science art exhibits nationwide, several artists got in touch to let me know about upcoming shows they are in. I updated the roundup accordingly and in the process, discovered four opening receptions in the next three weeks. If you are in the area and available, don't miss the opportunity to meet these accomplished artists face-to-face: Origin of the Universe. Evolution of the Universe. String Theory. Dark Matter. Dark Energy. Multiverse. Unification of Space + Time. Our Solar System. Cultural Cosmology. Art.Science.Gallery.’s science-inspired printmakers explore the cosmos in this far out exhibition for PrintAustin 2016, a city-wide printmaking festival. This exhibition explores the relationship between culture and nature, one of the oldest human tropes. In this recurring schism, humans believe ourselves to be of nature and, alternately, distinct from it. As we search texts and traditions to support either position, the persistence of the trope itself is underscored; it’s an impasse, shifting in form. It’s also an embrace of or a resistance to the natural world that produced us; from which we believe we stand apart. In Raw and Cooked, artists Jim Jacobs, Joshua Winegar, and Paul Crow present work within this nature/culture dialectic. Jacobs begins with an ancient horticultural intervention, the graft, to focus our attention on a literal intersection of the natural and the human-made. Winegar takes on the natural world as a partner in a conversation with his psyche, alternately responding to, and intervening in, the world which surrounds him. Crow maps the span of his life onto the time frame of the human awareness of global climate change. Each artist begins with material that exists before agency and brings it through a process of intervention to manifest a hybrid: the artist in dialogue both with the world and without, and with an inner understanding of that world. Artist and ocean advocate Courtney Mattison creates large scale ceramic installations and sculptures inspired by science and marine biology. Her intricate hand-crafted porcelain works celebrate the fragile beauty of endangered coral reef ecosystems and promote awareness to conserve and protect our natural world. Born and raised in San Francisco, Courtney received an interdisciplinary Bachelor of Arts in Marine Ecology and Ceramic Sculpture from Skidmore College in 2008 and a Master of Arts in Environmental Studies from Brown University with coursework at the Rhode Island School of Design in 2011. Mattison has exhibited her work nationally including at the Tang Museum in Saratoga Springs, NY, the headquarters of the National Oceanic and Atmospheric Administration (NOAA) and the American Association for the Advancement of Science (AAAS). She lives and works in Denver, Colorado. Organized by the Virginia Museum of Contemporary Art. Curated by Alison Byrne, Director of Exhibitions and Education. Exhibit details: Botanical Paintings in Colored Pencil by Nina Antze January 7, 2016 – April 25, 2016 Please call ahead 707-527-9277 x 107 to see exhibit Heron Hall, Laguna Environmental Center 900 Sanford Road, Santa Rosa, CA California Flora is an exhibit of botanical paintings by colored pencil artist Nina Antze. The paintings were created over the past eight years and focus mainly on California natives. Also included are paintings documenting Luther Burbank’s Experiment Farm in Sebastopol and a piece from the Alcatraz Florilegium, a documentation of the plants of the Alcatraz gardens. Nina Antze is a botanical artist and quilt maker living in Northern California. She has a degree in Fine Art from San Francisco State University and has a Certificate in Botanical Illustration from the New York Botanical Gardens. She teaches Colored Pencil classes in the Botanical Certificate Program at Filoli Gardens, at the Sebastopol Center for the Arts and around the Bay Area. Her botanical paintings and colored pencil drawings have been exhibited in New York, at the Huntington Library, and at Filoli Gardens and her quilts have won numerous awards. She works in colored pencil, watercolor pencil and fabric. Her botanicals can be viewed at her website, www.pcquilt.com Exhibit details: The Alcatraz Florilegium January 16 - 29, 2016 University of California Botanical Garden at Berkeley 200 Centennial Drive Berkeley, CA The Northern California Society of Botanical Artists (NCSBA) in collaboration with the Golden Gate National Parks Conservancy and the Garden Conservancy has created a florilegium, a series of botanical paintings, to document the plants of The Gardens of Alcatraz. The UC Botanical Garden is thrilled to welcome the NCSBA to exhibit this special showing of the Alcatraz Florilegium, with over 70 drawings and paintings, in the beautiful Julia Morgan Hall. For those unable to attend the exhibit in person, visit the online version here. _______________________________ If you have a scienceart exhibit that should be included in Symbiartic's regular scienceart roundup, with the relevant details.
News Article | March 23, 2016
Dr Jeffrey Mangel, a Darwin Initiative research fellow based in Peru, and Professor Brendan Godley, from the Centre for Ecology and Conservation at the University's Penryn Campus, were part of a team of researchers who found that attaching green battery powered light-emitting diodes (LED) to gillnets used by a small-scale fishery reduced the number of green turtle deaths by 64 per cent, without reducing the intended catch of fish. The innovative study, carried out in Sechura Bay in northern Peru was supported by ProDelphinus, the UK Government's Darwin Initiative, the National Oceanic and Atmospheric Administration and published in Marine Ecology Progress Series. It is the first time that lighting technology has been trialled in a working fishery. At a cost of £1.40 ($2) for each LED light, the research showed that the cost of saving one turtle was £24 ($34)—a sum which would be reduced if the method was rolled out at larger scale. Multiple populations of sea turtle species use Peruvian coastal waters as foraging grounds including green, olive ridley and hawksbill, loggerhead and leatherback. Peru's gillnet fleet comprises the largest component of the nation's small-scale fleet and is conservatively estimated to set 100,000 km of net per year in which thousands of turtles will die as 'bycatch' or unintentionally. The researchers used 114 pairs of nets, each typically around 500-metres in length. In each pair, one was illuminated with light-emitting diodes (LEDs) placed every ten metres along the gillnet floatline. The other net in the pair was the control and not illuminated. The control nets caught 125 green turtles while illuminated nets caught 62. The target catch of guitarfish was unaffected by the net illumination. They are now working with larger fisheries in Peru and with different coloured lights to see if the results can be repeated and applied with more critically endangered species. "This is very exciting because it is an example of something that can work in a small-scale fishery which for a number of reasons can be very difficult to work with. These lights are also one of very few options available for reducing turtle bycatch in nets," said Dr Mangel, who is one of the lead authors on the paper and ProDelphinus Research Co-ordinator. "The turtle populations in the eastern Pacific are among the world's most vulnerable and we are hoping that by reducing bycatch, particularly in gillnets, will help with the management and eventual recovery of these populations." Thousands of endangered turtles die as bycatch in gillnet fisheries around the world and it is hoped that this study will help to provide a solution. Professor Brendan Godley notes, "It is exciting to be part of research that is highlighting innovative methods that may assist the move towards sustainability in these fisheries. Understanding costings will help emphasize the need for institutional support from national ministries, international non-governmental organizations and the broader fisheries industry to make possible widespread implementation of net illumination as a sea turtle bycatch reduction strategy." "Bycatch is a complex, global issue that threatens the sustainability and resilience of our fishing communities, economies and ocean ecosystems," said Eileen Sobeck, assistant NOAA administrator for fisheries. "Funding research like this is key to NOAA's efforts to reduce bycatch. Through this work, we can better protect our natural resources." More information: N Ortiz et al. Reducing green turtle bycatch in small-scale fisheries using illuminated gillnets: the cost of saving a sea turtle, Marine Ecology Progress Series (2016). DOI: 10.3354/meps11610
News Article | October 12, 2016
Chemical testing of the source of marine food products could be a powerful tool to help to fight food fraud, maintain healthy sustainable fish stocks or marine protected areas, and ensure consumer confidence in marine eco-labelling. Tracing the location of marine animals is difficult as they generally can't be seen and are often a long way from the nearest person. The Southampton research team, led by Dr Clive Trueman and PhD student Katie St John Glew, built maps of chemical variation in jellyfish caught across the North Sea. They then compared the same chemical signals in scallops and herring caught in known places across the North Sea, and used statistical tests to find the areas of the North Sea with the most similar chemical compositions. These chemical tests were able to accurately link scallops and herring to their true locations, and can be used to test if the chemical composition of an animal matches a claimed area of origin. Dr Trueman, Associate Professor in Marine Ecology, said: "Understanding the origin of fish or fish products is increasingly important as we try to manage our marine resources more effectively. Fish from sustainable fisheries can fetch a premium price, but concerned consumers need to be confident that fish really were caught from sustainable sources. "Recently, genetic tests have revealed widespread mislabelling of the type of fish being sold worldwide, but currently we don't have any way of testing where a fished product was caught." The study was published in the journal Methods in Ecology and Evolution. Explore further: What fish ears can tell us about sex, surveillance and sustainability