Furlan N.,Fisheries Institute |
Esteves K.E.,Institute Pesca |
Quinaglia G.A.,Companhia Ambiental do Estado de Sao Paulo CETESB
Environmental Biology of Fishes | Year: 2013
The rivers and streams of the large urban centers in Southeast Brazil are increasingly being degraded, demanding expanded conservation efforts. This study was conducted in the Grande River, one of the main tributaries of the Billings Complex, a reservoir that is a strategic fresh water resource for the São Paulo metropolitan region. Water quality, habitat features and fish fauna were investigated at seven sites along the longitudinal gradient with the aim of identifying the distribution patterns and relative contributions of the environmental factors. The water samples and environmental characteristics were recorded, and fish were collected during the rainy (January to March) and dry seasons (July and August) of 2009. The water quality varied along the river, with higher values of conductivity, fecal coliforms and total phosphorus in the lower reach, indicating a strong influence of the urban area. Twenty-two fish species were recorded, two of which are considered endangered. A canonical correspondence analysis (CCA) indicated marked differences in species composition between the river's upper and lower reaches, which was mainly attributed to vegetation cover and the presence of different meso-habitats, such as riffles and pools. Trychomycterus spp. and Astyanax paranae were associated with the upper reaches, while Astyanax fasciatus and Astyanax bockmanni, Cyphocharax modestus, Hoplias malabaricus and Hypostomus ancistroides occurred in the lower reaches. Despite the disturbance in water quality and riparian vegetation in the lower river section, no detectable changes in community structure were observed. However, the presence of some tolerant species, such as Astyanax fasciatus, Hoplosternum littorale and Hypostomus ancistroides, may indicate that the community is experiencing initial stages of disturbance. © 2012 Springer Science+Business Media B.V.
dos Santos F.B.,Fisheries Institute |
Esteves K.E.,Fisheries Institute APTA
Environmental Management | Year: 2015
A multimetric, fish-based Index of Biotic Integrity (IBI) was developed and tested to assess the ecological status of streams with different riparian conditions in the Piracicaba River Basin. Nine streams with three categories of riparian zone preservation were selected: native forest (NF) with preserved forest, secondary forest (SF) with forest in an advanced state of regeneration and surrounded by sugarcane plantations, and sugarcane (SC) without riparian vegetation and surrounded by SC crops. A continuous scoring system was employed, and candidate metrics were tested for range, responsiveness, and redundancy, resulting in the selection of eight metrics to compose the index. The final IBI score was positively correlated with an Environmental Index both in the dry (Spearman’s rho = 0.76; P = 0.01) and rainy seasons (Spearman’s rho = 0.66; P = 0.04), suggesting that this IBI is a suitable tool for the assessment of the biological conditions of these streams. The highest IBI values were observed in the rainy season at the NF and SF sites, with significant differences between the NF and SC sites (Kruskal–Wallis test: P = 0.03). The results indicated some variability in the biological integrity at SF and SC sites, suggesting a relationship with the intensity of the management of this crop. Patterns were consistent with other studies that have shown the effects of agriculture on the environmental quality of streams, which indicate the importance of the riparian zone to the maintenance of ecosystem integrity and supports the use of the IBI for biological monitoring in similar regions. © 2015, Springer Science+Business Media New York.
Bernadochi L.C.,Fisheries Institute |
Alves J.L.,Cocanha Beach Fishermen and Mariculturist Association MAPEC |
Marques H.L.A.,Fisheries Institute
Aquaculture Research | Year: 2016
In Southeastern Brazil, there is good cultivation potential for the pearl oyster Pinctada imbricata, which is often found on mussel ropes or seed collectors across the north coast of Sao Paulo State. Despite this, very few studies have focused on the biology of this species in Brazil. This research aimed to partially address this lack of information by evaluating the optimal season and preferred depth range (surface, first and second metres of depth) for the settlement of juvenile P. imbricata on artificial collectors. Two replicate artificial collectors made from braided fishing nets and comprising of horizontally and vertically suspended lines were deployed at Cocanha Beach, Brazil, and left in situ for a period of 5 months. At the end of the deployment period, the density of juveniles was significantly greater on the surface than the first and second metres of depth. It was also found that the period from November to March was more favourable for the placement of collectors and settlement of juveniles. Furthermore the results of the study confirm that is feasible to capture juvenile P. imbricata using artificial collectors to provide a continuous supply of commercial cultures. © 2016 John Wiley & Sons Ltd.
De Almeida Marques H.L.,Fisheries Institute |
Moraes-Valenti P.M.C.,Fisheries Institute
Aquaculture Research | Year: 2012
This article describes some aspects of the current status of Macrobrachium rosenbergii (De Man 1879) and Macrobrachium amazonicum (Heller 1862) farming in Brazil, including a brief description of the technologies used. A history of the farming of M. amazonicum is provided, together with the marketing strategies currently employed for freshwater prawns in Brazil and future trends. It was concluded that freshwater prawn farming in Brazil currently has a favourable scenario for expansion due to increasing demand and to prospects of an improved organization of the productive chain. © 2012 Blackwell Publishing Ltd.
Telli G.S.,Fisheries Institute |
Ranzani-Paiva M.J.T.,Fisheries Institute |
Dias D.D.C.,Fisheries Institute |
Sussel F.R.,APTA |
And 2 more authors.
Fish and Shellfish Immunology | Year: 2014
An 84-day feeding trial was conducted to evaluate the effect of the dietary administration of Bacillus subtilis on the growth performance, body composition, intestinal probiotic recovery, hematology, and non-specific immunity of Nile tilapia (Oreochromis niloticus) raised at two stocking densities. Five hundred twenty male Nile tilapias (32.63±1.25g) were distributed in 16,800-L tanks. The experimental design was completely randomized using four replications and a 2×2 factorial scheme with two stocking densities (18.75fishm-3 62.50fishm-3) and two diets (control and with probiotic). The probiotic-supplemented diet included 5×106CFUgfeed-1. There were no significant differences (P>0.05) in the growth performance, body composition, and levels of cortisol and glucose between the animals fed with the control diet and the animals fed with the probiotic-supplemented diet. Differences in the growth performance were observed between the fish reared at different stocking densities; in particular, the fish raised at the high stocking density exhibited reduced weight gain, feed intake, and specific growth rate compared with those raised at the low stocking density. The B. subtilis remained viable after its inclusion in the feed, storage, and passage through the stomach, which demonstrations the feasibility of using this bacteria as a probiotic. Higher values (P<0.05) in the plasma lysozyme levels and phagocytic activity were observed in the fish that received the probiotic-supplemented diet and reared at the high stocking density, but this difference was not observed in the fish raised at the low stocking density and fed the different diets. The administration of the probiotic caused decreases in the number of erythrocytes and the hematocrit level in the fish reared at the high stocking density, but these erythrocytes showed higher values of mean corpuscular hemoglobin. The stocking density was shown to be a stressor agent that causes a lower fish growth rate. The fish fed the control diet and raised at the high stocking density had lower lysozyme levels than the fish subjected to the other treatments. The inclusion of the probiotic bacteria B. subtilis at a concentration of 5×106CFUgfeed-1 benefited the innate immune system of Nile tilapia by decreasing the stress associated with exposure to a high stocking density, increasing the mean corpuscular hemoglobin, and improving the innate immune system (lysozyme and phagocytic activities of macrophages). © 2014 Elsevier Ltd.
Eichbaum Esteves K.,Fisheries Institute |
Alexandre C.V.,Fisheries Institute
International Review of Hydrobiology | Year: 2011
A fish-based Index of Biotic Integrity (IBI) was adapted for use in a stream of the heavily impacted Piracicaba River basin in southeastern Brazil. The influences of land use (mainly sugar-cane crops) and an urban area on the fish community were investigated at ten sites along a 17 km-long stream during the dry and rainy season. The IBI varied with the season and location along the stream, reflecting differences between the agricultural and urban sites, which were more pronounced during the dry season. The final index was positively correlated with a Habitat Quality Index (dry season) but not with a Water Quality Index. The results can be viewed as a tool for assessing and monitoring the ecological health of streams in this watershed. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Moreira A.A.,University of Sao Paulo |
Moreira A.A.,Mogi Das Cruzes University |
Tomas A.R.G.,Fisheries Institute |
Hilsdorf A.W.S.,Mogi Das Cruzes University
Journal of Experimental Marine Biology and Ecology | Year: 2011
Octopus vulgaris is a cephalopod species in several oceans and commonly caught by artisanal and industrial fisheries. In Brazil, O. vulgaris populations are mainly distributed along the southern coast and have been subjected to intensive fishing during recent years. Despite the importance of this marine resource, no genetic study has been carried out to examine genetic differences among populations along the coast of Brazil. In this study, 343 individuals collected by commercial vessels were genotyped at six microsatellite loci to investigate the genetic differences in O. vulgaris populations along the southern coast of Brazil. Genetic structure and levels of differentiation among sampling sites were estimated via a genotype assignment test and F-statistics. Our results indicate that the O. vulgaris stock consists of four genetic populations with an overall significant analogous FST (ΦCT=0.10710, P<0.05) value. The genetic diversity was high with an observed heterozygosity of Ho=0.987. The negative values of FIS found for most of the loci examined suggested a possible bottleneck process. These findings are important for further steps toward more sustainable octopus fisheries, so that this marine resource can be preserved for long-term utilization. © 2011 Elsevier B.V.
News Article | August 31, 2016
Savage found that pondweeds in the presence of light stimulate spawning in Xenopus laevis ... This finding prompts me to report my own experience with this amphibian under more natural conditions ... At the Provincial Fisheries Institute, Lydenberg, fishponds ... are filled with water and fertilized with fowl manure in spring for the breeding of fish. Within 2 or 3 days after fertilization such ponds usually contain large numbers of Xenopus, which immediately start spawning, so that by the time plankton has developed the pond is teeming with larvae ... that they are attracted by fertilized water and spawn before an algal bloom develops suggests that the primary stimulus for spawning ... could be the fertilizer. Mr. Beebe has had a wide experience of jungle-life in many lands, and hence his latest experiences in Brazil have the greater value ... Abundance of species and a relative fewness of individuals, he remarks, are pronounced characteristics of any tropical fauna ... He quickly discovered that more was to be obtained by watching particular trees ... [D]uring the space of a week of intermittent watching he obtained no fewer than seventy-six new species ... Just before leaving a brilliant idea struck Mr. Beebe ... he suddenly bethought him to fill a bag with four square feet of jungle earth, and this was examined ... while on board ship on the voyage home ... Among the captures thus made were representatives of two genera of ants new to science. There can be no doubt that important discoveries ... would accrue if this example of Mr Beebe's were generally followed in the future.
News Article | March 18, 2016
Women who eat as much seafood as the FDA recommends for people who are pregnant — or who eat slightly more — may be exposing themselves to unsafe levels of mercury depending on the kinds of fish they’re eating, says a new study just published by the Environmental Working Group (EWG). The report calls for more detailed federal guidelines on what types of fish are safe, and in what quantities. But an industry group has already criticized the study. The National Fisheries Institute, a trade organization representing the seafood industry, released a statement Tuesday decrying the report’s “fear-mongering,” even as other academics supported its basic conclusions. Mercury contamination in the environment comes from a variety of sources, mainly industrial pollution. Mercury that makes it into water systems and eventually into the ocean can be consumed by small organisms and work its way up the food chain in larger and larger amounts, which is why it tends to exist in the highest levels in large, predatory fish — often the kinds of fish that people like to eat, such as certain species of tuna. In previous decades, nutritionists have recommended that pregnant women abstain from seafood entirely to avoid exposing their developing babies to harmful mercury. But in the past decade or so, “we’ve seen the nutritional science shift to say that there are benefits to eating seafood,” said the new report’s lead author Sonya Lunder, a senior analyst at the EWG, a nonprofit environmental group with a long history of working on the mercury issue. The most widely touted of these benefits is the prevalence of omega-3 fatty acids, which are considered essential for human health but can’t be made naturally by the body. There are three types of omega-3s, two of which are found mainly in seafood. Research has suggested that consuming these omega-3s during pregnancy can aid in a fetus’s development, which is the major reason nutritionists now generally give pregnant women a complex recommendation: consume a moderate amount of seafood, adhering to certain federal guidelines to create a safe level of mercury exposure. In 2014, the FDA and EPA jointly released a new draft set of guidelines to aid in just that. Overall, for pregnant women and some other groups, the guidelines recommend eating 8 to 12 ounces of a variety of fish each week, and list a number of healthy, low-mercury examples, including salmon, shrimp and light canned tuna, as well as four types of fish to avoid entirely: tilefish from the Gulf of Mexico, shark, swordfish and king mackerel. They also recommend limiting the consumption of albacore tuna to 6 ounces or less per week. But the EWG’s report suggests that may not be specific enough. A study of more than 250 women of childbearing age who ate approximately the amount of seafood recommended by the federal guidelines found that around 30 percent of them had higher mercury levels in their bodies than is considered safe by the EPA. On average, the participants were found to have mercury levels 11 times higher than those of a control group of women who ate seafood rarely or not at all (though the control group consisted of only 29 individuals). The results suggest that study participants may not be choosing the most optimal fish for low mercury and high omega-3 intake. The study estimated, for instance, that tuna accounted for about 40 percent of all the participants’ mercury intake — a result that may have been caused in part by the guidelines’ incomplete recommendations when it comes to tuna consumption, Lunder pointed out. The government recommends light canned tuna — which is usually composed of skipjack tuna — as a healthy seafood choice that’s low in mercury. However, canned tuna comes in many other varieties, some of which include different species with generally higher mercury concentrations. Canned white tuna, for instance, is usually made from albacore tuna, which can have mercury concentrations several times higher than skipjack. The importance of differentiating between the different types of canned tuna is not articulated in the guidelines. In fact, Lunder noted, when surveyed many of the study’s participants were unsure exactly what type of canned tuna they’d been eating. Additionally, participants reported eating many other forms of tuna, including tuna steaks and tuna sushi, which often are made from species with relatively high mercury contents. None of these are specifically addressed in the guidelines, either. In general, Lunder said, the EWG continues to support the recommendation that pregnant women consume more seafood. But, she added, “We think that those recommendations need to be paired with much more detailed information about moderate- and high-mercury species that would pose a risk if you eat them.” Other experts agree that better information needs to be included in the guidelines — it just needs to be done carefully. “I think that the recommendations that this group make are reasonable — the challenge is that there’s a trade-off in providing more information,” said Roxanne Karimi, a research scientist at Stony Brook University who has conducted similar research. “Overall, more information is good so that consumers can make decisions on their own, but it can also be confusing, and there’s a concern that consumers will be discouraged from eating fish altogether, even when there’s an overall benefit.” Sharon Sagiv, an assistant adjunct professor of epidemiology at the University of California Berkeley, noted that the FDA/EPA guidelines already list some specific recommendations when it comes to which fish to avoid and which fish might be better choices. So one question is whether the participants in the study were unclear about some of these recommendations (for example, the recommendations on tuna) or did not strictly heed them. Lunder pointed out that strict adherence to the types of fish recommended was not a requirement for participation in the study, and indeed some women did report eating fish that the guidelines specifically warn against, such as swordfish. So the issue is not that the existing recommendations are wrong. Rather, the report urges more specific and detailed instructions to consumers that may make it less likely for women to misunderstand the guidelines. “FDA and EPA can put out these recommendations, but if they’re at all complicated in terms of their message that’s a problem because it means that women aren’t necessarily getting effective risk communication,” Sagiv said. Sagiv has conducted research on the effects of prenatal exposure to both mercury and fish consumption. A 2012 study she co-authored found that low-level prenatal mercury exposure was associated with a greater risk for ADHD behaviors in children, but fish consumption during pregnancy can actually protect against these behaviors. “These findings underscore the difficulties of balancing the benefits of fish with the detriments of low-level mercury in developing dietary recommendations in pregnancy,” she and her colleagues wrote in the paper — a conclusion that aligns closely with the EWG’s new report. The EWG’s study has not been received favorably by all, however. “Published peer-reviewed science that takes into account the befits of omega 3’s and the risks of mercury together…is accepted and understood as the gold standard,” the National Fisheries Institute’s statement says. “Consumers don’t eat fish with a side of mercury, studying it that way only works to further EWG’s agenda when they don’t agree with the avalanche of research that stands in contrast to the narrative they are pushing to the press.” Aside from the value of revamping the seafood guidelines, Lunder noted that the report highlights the continued need for policies aimed at reducing mercury pollution. In 2013, the U.S. was one of nearly 150 countries to ratify the Minamata Convention on Mercury, an international treaty aimed at reducing mercury emissions worldwide. The report calls for strong and effective implementation of the treaty. Such steps will be necessary to protect both the environment and human health, Lunden noted. “Since we’ve polluted nature’s perfect food, we now have to look to changing human habits and patterns in order to protect ourselves from these known toxins,” she said. And Sagiv echoed her sentiments. “If we didn’t have contaminated seafood, we wouldn’t have to advise women not to eat [certain types of] fish,” Sagiv said. “Unfortunately, we’re in an environment where we do have to worry about that, and that risk communication is really very important.”
News Article | November 29, 2016
Nicholas S. Fisher got a research opportunity he couldn’t pass up. When he embarked on a study of fish two years ago, he didn’t know what he was looking for. All he knew was that a researcher in Massachusetts had samples of nearly 1,300 Western Atlantic bluefin tuna in a deep freeze and was offering them up for investigation. Today, his team’s findings are being greeted as some of the most positive news in a while related to the lowering of power-plant emissions. Studies of tuna caught in the Gulf of Maine between 2004 and 2012 revealed that levels of methylmercury in their bodies decreased at a rate of 2 percent per year, or nearly 20 percent over a decade. “The decline is real,” Fisher, a professor of marine sciences at Stony Brook University in New York, said Monday. “The decline is almost in parallel with declines in mercury emissions from coal-fired power plants and the decline of mercury in the air. It appears that the fish are responding almost in real time. We thought that was pretty exciting.” [Study links warmer water to greater levels of mercury in fish] The decreases occurred as coal-fired power plants began closing in 2008 — with 300 now shut down, according to the National Mining Association. Four years before that date, the carcasses of bluefin tuna, regardless of age, size and sex, had a lot more mercury than four years after. The research was published this month in Environmental Science and Technology. Make no mistake, the fish still contained dangerously high levels of mercury, a substance that’s especially harmful to pregnant women and children. But the research showed that the benefits of lowering coal emissions as power plants switch to natural gas are almost immediate and measurable. A high consumption of tuna accounts for more than 40 percent of mercury concentrations in humans, more than any other source, the study said. Bluefin tuna, which often wind up as sushi, tend to have the highest levels of mercury of any type of tuna. Yellowfin tuna tend to have more moderate levels, and skipjack tuna’s mercury levels are relatively low. Since tuna are an apex predator, near the top of the marine food chain, mercury in the fish they eat accumulates in their bodies. “Fish acquire about 95 percent of mercury from their diet,” Fisher said, with a much smaller amount absorbed just from swimming in toxic waters. No research has determined that mercury levels have also dropped in the smaller fish on which bluefin prey. “We can only speculate that that is the case,” Fisher said. But he expects that result would be found. [Federal officials want to track every fish and crustacean shipped to a U.S. port] He would not speculate about mercury levels in fish outside the Gulf of Maine: “In the Pacific, increased emissions in China and Asia could be increasing it. It may be an entirely different story.” The National Fisheries Institute, an industry group that represents restaurants and seafood wholesalers, called the study interesting, but said Americans eat only a tiny amount of bluefin tuna per capita, and “this study is not particularly relevant to the safety or healthfulness of the fish we eat with any regularity in the U.S.,” said a spokeswoman, Lynsee Fowler. There’s a heated debate over the safety of canned tuna, and not surprisning NFI aligns with those who say consumers have nothing to worry about. “The level of mercury in canned tuna remains not only unchanged but completely safe… On whole, it’s a study worth looking at but the levels of mercury in seafood are simply not making consumers sick,” she said. Fisher’s team would next like to study whether methylmercury that’s also found in the brains of tuna affects their behavior, such as how they swim or relate to each other. Both are things science doesn’t know. For now, Fisher said, he’ll settle for his study’s good news. “It says that you know you don’t have to look at all the mercury in the seafood and wring your hands and say, ‘Oh my God, there’s nothing that can be done about this,’ ” he said. “It appears that something can be done, and there’s a positive benefit in real time. You don’t have to wait for decades.” How your sunscreen contributes to the destruction of ocean coral Up to 32 percent of imported seafood is illegally caught, a study says Scientists say climate change is threatening the life blood of Canada’s native people