Aquatic Bird Species Research Articles

Railways as a potential bird census tool in citizen-science projects: a preliminary study

ABSTRACTCapsule: Bird surveys carried out during a railway journey capture a significant proportion of the species and individuals recorded through line transects (LT).Aims: To explore the suitability of railways as a bird census tool in a scenario where bird data massively recorded by passengers of the railway network could be collected through appropriate web portals and cell phone technologies.Methods: Railway and walked transects were conducted along the 40 km rail line connecting the towns of Valencia and Buñol, Spain. From June 2012 to May 2016, I carried out a weekly survey of birds from the railway line looking through the train window. Additionally, to assess the efficacy of train surveys, a railway section 11 km long was surveyed monthly on foot from December 2014 to November 2015.Results: Train surveys were unsuitable to detect many woodland birds but were relatively efficient in detecting raptors, open-field and aquatic bird species. About 75% of non-woodland species were detected from the train, and there was a positive correlation between counts obtained through train and LT; mean detection rate per species was between 50% and 80% depending on the season. Overall, larger and numerically more important species were better quantified. Further, detection rates of several medium-large species were greater than one, indicating a superior efficiency of train over LT. Only for nine species were data sufficient to calculate population trends, which in several cases were similar to those obtained through monitoring programmes operating at coarser spatial scales.Conclusions: The relatively high performance of the method and the fact that broad geographical areas could be easily surveyed (even on a daily basis) by many people in a relatively short time make railway-based bird surveys a candidate to be used in citizen science programmes.

Potential of Ecological Resources and Ecotourism Destination Management: A Case Study in Koh-Mak Community, Southern Thailand

Conserving the biodiversity richness is the paramount of the development of sustainable ecotourism and destination management. In Southern Thailand, Koh-Mak Community is one of well-known ecotourism destinations within Phayun District within Phattalung Province. Local people livelihoods in Koh-Mak community based on the quantity and quality of fishery and agriculture production including their community-based ecotourism (CBE) ventures. This study aimed to assess the potential of ecological resources within the Koh-Mak ecotourism destinations for providing the practical guidelines of the sustainable ecotourism practices. The mixed research methods were applied in this study by using questionnaires by quota sampling of the total 337 research participants with semi-structured questions for obtaining their opinion of CBE ventures, and using the potential assessment and weighting score equation for evaluating the contributory factors of ecological resources. Researchers found that the consistency willingness of local community engagement in CBE ventures is a vital key of sustainable tourism development in long-term. The results of potential assessment shown that the Koh Mak community areas held the total biodiversity richness at 3.4, which is consisted of the highest value of aquatic ecological resources at 4.4, local vegetation species at 4, and the aquatic bird species at 3.7 by respectively. Community leader suggested that the needs of CBE improvement are reliability collaboration management and equity benefit sharing among the related stakeholders and Koh Mak community members. Community members also recommended that the establishment of the newly ecotourism routes have to consider the continuity of the sustainable management practices to maintain the potential ecological resource as well as conserve their traditional knowledge of fishery and local cultures. Therefore, the continuity of good governance is needed to develop the existing CBE ventures towards the sustainable development.

Avifaunal community structure associated to El Conchalito mangrove, BCS, Mexico under different tide conditions

The importance in the study of avian community structure relates to their relevant role in theecosystem. Specially, when they are exposed to collateral damage by anthropogenic activities. The goal of thisresearch was to determine the variation of avian community structure in the mangrove forest El Conchalito, BCSthrough the use of ecological indices such as diversity (H’), dominance (D), and the biological value index (IVB)in April-June of 2016 during the seasonal transition from Spring-Summer. To describe the environmental frame,measurements of temperature, noise level, and chlorophyll a were made, and other climatological data were used.A total of 15 species of aquatic, marine or shore birds were recorded (5 orders, 7 families and 9 genera), and 3species of terrestrial birds (2 orders, 2 families and 3 genera). Maximum bird abundances were observed duringthe first sampling. Diversity values varied between H´= 1.1 and H´= 1.8, with maxima at the beginning and atthe end of the study period. This was related with the low tides and the increase of species richness, respectively.Noise level and chlorophyll a concentration, were not associated directly with the changes observed in the community structure. Species richness was associated directly with temperature increase. The most important birdspecies were: Egretta thula (96.9%), Zenaida asiatica (88.7%), Numenius phaeopus (86.8%), and Egretta rufescens (83.8); less important was Ceryle alcyon (28.2). Three species protected under NOM-059-SEMARNAT-2010were identified.

Influenza study of backyard animals in Georgia

ObjectiveThe purpose of this study was to identify zoonotic influenzaviruses in swine and poultry populations in Georgia and to definetheir pandemic potential.IntroductionAquatic birds are the main reservoirs of influenza viruses,however pigs represent an essential host in virus ecology as they aresusceptible to both avian and human influenza viruses. Circulatingzoonotic influenza (A/H7N9, A/H5N1, and A/H3N2v) viruses couldmutate into forms easily transmissible from human-to-human andbecome a public health concern. Georgia is located along routes usedby migrating birds where different species of aquatic birds are found.In 2006, highly pathogenic influenza virus A/H5N1 was detected intwo wild swans in Adjara (western Georgia). Moreover, in the frameof wild bird surveillance, various subtypes of influenza A viruseswere detected in mallard and gulls in Georgia (Lewis, 2013). Thusdomestic animals in Georgia have a potential chance to contractinfluenza viruses from wild birds.MethodsThe Kakheti region, the leading region in cattle breeding andpoultry production in Georgia, was selected for study. Villages wereselected for door-to-door visits to search for ill backyard animalsshowing influenza-like symptoms. In case of identification of a sickanimal, samples were obtained for laboratory investigations; samplecollection forms were filled out to generate epidemiological data.Cloacal and tracheal swabs were taken from poultry; and pharyngealand nasal swabs were collected from pigs. Each specimen wasscreened for influenza A matrix gene by real-time RT-PCR using aprotocol from the Centers for Disease Control Prevention.ResultsEighty four villages in the Kakheti region were surveyed fordomestic animals with influenza-like illness symptoms. In total,164 specimens were collected from 112 backyard animals in55 households (107 samples were from 55 poultry and 57 sampleswere from 57 pigs). All samples tested negative for Influenza A virusby real time RT-PCR. The questionnaire data revealed that the agerange of both pigs and poultry varied from one month to two years;median and mode were both 1 year. Chickens and ducks primarilyfreely ranged in backyards (67%), while half the number of pigs werekept in closed premises. Equally, 61% of pigs and poultry had contactwith other pigs or poultry within the premises.ConclusionsIn spite of the negative findings, we cannot exclude the circulationof influenza viruses in domestic animals in Georgia. Especially,considering the fact that a domestic duck with influenza A/H10virus was identified during veterinarian training in 2010 in Grigoleti(Black sea cost of Georgia) manifesting no clinical symptoms.Therefore, larger scale studies, including swabbing more backyardanimals without any clinical symptoms are necessary to identify inter-species virus transmission in the country.

Evidence of Intercontinental Spread and Uncommon Variants of Low-Pathogenicity Avian Influenza Viruses in Ducks Overwintering in Guatemala.

Over a hundred species of aquatic birds overwinter in Central America's wetlands, providing opportunities for the transmission of influenza A viruses (IAVs). To date, limited IAV surveillance in Central America hinders our understanding of the evolution and ecology of IAVs in migratory hosts within the Western Hemisphere. To address this gap, we sequenced the genomes of 68 virus isolates obtained from ducks overwintering along Guatemala's Pacific Coast during 2010 to 2013. High genetic diversity was observed, including 9 hemagglutinin (HA) subtypes, 7 neuraminidase (NA) subtypes, and multiple avian IAV lineages that have been detected at low levels (<1%) in North America. An unusually large number of viruses with the rare H14 subtype were identified (n = 14) over two consecutive seasons, the highest number of H14 viruses ever reported in a single location, providing evidence for a possible H14 source population located outside routinely sampled regions of North America. Viruses from Guatemala were positioned within minor clades divergent from the main North American lineage on phylogenies inferred for the H3, H4, N2, N8, PA, NP, and NS segments. A time-scaled phylogeny indicates that a Eurasian virus PA segment introduced into the Americas in the early 2000s disseminated to Guatemala during ~2007.1 to 2010.4 (95% highest posterior density [HPD]). Overall, the diversity detected in Guatemala in overwintering ducks highlights the potential role of Central America in the evolution of diverse IAV lineages in the Americas, including divergent variants rarely detected in the United States, and the importance of increasing IAV surveillance throughout Central America. IMPORTANCE Recent outbreaks of highly pathogenic H7N3, H5Nx, and H7N8 avian influenza viruses in North America were introduced by migratory birds, underscoring the importance of understanding how wild birds contribute to the dissemination and evolution of IAVs in nature. At least four of the main IAV duck host species in North America migrate through or overwinter within a narrow strip of Central America, providing opportunities for diverse IAV lineages to mix and exchange gene segments. By obtaining whole-genome sequences of 68 IAV isolates collected from migratory waterfowl in Guatemala (2010 to 2013), the largest data set available from Central America to date, we detected extensive viral diversity, including gene variants rarely found in North America and gene segments of Eurasian origin. Our findings highlight the need for increased IAV surveillance across the geographical span of bird migration flyways, including Neotropical regions that have been vastly undersampled to date.

Astroviruses in poultry

Astroviruses are small, round, nonenveloped viruses with star-like morphology and a diameter of 25-35 nm, and their genome constitutes linear, positive-sense ssRNA of about 7 kb of size. Astroviruses are known to cause enteritis in humans, as well as in different animal species, including sheep, cattle, swine, dogs, cats and mice. In poultry, they cause enteritis combined with growth depression and higher mortality, but may also cause other pathological conditions. Duck astrovirus (DAstV) infections trigger hepatitis with a high morbidity and mortality of ducklings. Infections of chickens with avian nephritis virus (ANV) cause diarrhea, growth retardation, kidney damage and gout, resulting in increased mortality. Recently, another member of this group, chicken astrovirus (CAstV), has been described as the etiological factor of “white chicks” condition. Astroviruses have also been detected in domestic geese, guinea fowl, pigeons and different species of wild aquatic birds, and all of them belong to the Astroviridae family, the Avastrovirus genus. Initially, they were further divided into separate species, depending on their host of origin. According to these criteria, six different astroviruses were identified in avian species – in turkeys: turkey astrovirus type 1 (TAstV-1) and type 2 (TAstV-2), in chickens: ANV and chicken astrovirus, and in ducks: DAstV type 1 (DAstV-1) and type 2 (DAstV-2). However, since astroviruses can be transmitted between different species, this classification was replaced with one based on the amino acid structure of viral capsid protein. Currently, astroviruses detected in avian species are classified into three official avastrovirus species: 1, 2, and 3. This review presents data on the replication, pathogenesis, and diagnosis of astroviruses, as well as on the control and prevention of astrovirus infection.

Results of Epidemiological Monitoring Bird Flu in Kyrgyz Republic

The results of the study with modern molecular genetic research methods the circulation in the Kyrgyzstan territory avian flu virus in waterfowl and humans. Tested 3032 samples from 106 species of wild aquatic birds, of which 46 samples detected the flu virus, the proportion of positive samples was 1.5% (95% CI = 1.1 1.9). In 17 species of birds able to detect flu viruses. Avian influenza virus is more likely to appear among the following species of wild aquatic birds: black-headed gull, mallard, snipe, river terns, coots, common teal. Influenza A(H5N1) was found only in three samples from three birds: caspian gull, black-headed gull and mallard. Among people with clinical symptoms of acute respiratory infection and flui the laboratory testing virus A(H5N1) is not detected. The level of flu and acute respiratory viral infection of the population in areas located near lakes and wintering wetland birds was similar to that in other regions of the country.

Сезонная динамика гидрофильного орнитокомплекса бухты Круглая (Севастополь, Чёрное море)

Актуальность изучения гидрофильных птиц в городских зонах черноморского побережья обусловлена их важной ролью в структуре прибрежных биоценозов и необходимостью сохранения биоразнообразия в условиях антропогенной трансформации береговой зоны Крыма. Исследована динамика видового состава и численности птиц бухты Круглая (Севастополь). Материал собран в 1995 и 2005–2016 гг. В бухте Круглая установлено пребывание 51 вида водных и околоводных птиц из 8 отрядов. Зимний орнитокомплекс наиболее разнообразен и многочислен (32 вида: 14 Anseriformes, 7 Charadriiformes, 5 Podicipediformes, 3 Gruiformes, 2 Pelecaniformes, 1 Gaviiformes). Регулярно зимуют и количественно доминируют 8 видов – Cygnus olor, Anas platyrhynchos, Aythya ferina, Aythya fuligula, Fulica atra, Larus ridibundus, Larus cachinnans и Larus canus. Определены численность всех видов птиц, возрастной состав Cygnus olor и половой состав Anas platyrhynchos, Aythya ferina и Aythya fuligula. Основу орнитокомплекса составляли бентофаги (не менее 13 видов), ихтиофаги (5) и эврифаги (4). Отмечено 30 пролётных и кочующих видов, преимущественно Charadriiformes (11), Anseriformes (7) и Ciconiiformes (5). Гнездовой орнитокомплекс отсутствовал, только в 2016 г. зарегистрировано гнездование Ixobrychus minutus. Весенний пролёт проходил с конца февраля до мая, осенний –– с августа до первой декады ноября. Для сохранения данной бухты как ценного природного и эколого-воспитательного объекта целесообразно придание ей статуса природного парка.

Heavy metals in the mallard Anas platyrhynchos from eastern Austria.

A total of 77 specimens of the mallard Anas platyrhynchos were sampled from the eastern part of Austria before the ban on lead gun shot for hunting water fowl. Samples of muscle and liver were analyzed for their content of Cr, Cu, Zn, Ag, Cd, Hg and Pb using atomic absorption spectrometry. In addition the Hg content of feather samples from this aquatic bird species was evaluated. Results generally show higher concentrations of the metals in the liver compared to muscle; for mercury the concentrations were feathers>liver>muscle. Elevated, in some cases critical concentrations of Cr, Cu, Cd, Hg and Pb were measured. Levels of Ag were recorded for the first time for this species from Europe, providing basic information for future evaluation of this upcoming pollutant in aquatic environments.

Status of the Northern Silvery Grebe Podiceps juninensis in the northern Andes: recent changes in distribution, population trends and conservation needs

SummaryThe Northern Silvery Grebe Podiceps juninensis is an aquatic bird species considered Vulnerable to extinction in Ecuador and Endangered in Colombia. Globally the species is considered Near Threatened. Herein we report recent changes in distribution and population trends for the subpopulation in the northern Andes (Ecuador, Colombia), which is small and isolated. The Northern Silvery Grebe has undergone two documented extirpations, and at least one colonisation event, over the last three decades. More than 90% of the subpopulation relies on two wetlands, La Mica and Colta lakes in Ecuador, with the latter facing an accelerated sedimentation process which jeopardizes the fate of the wetland, and the species, in the mid-term. The population of La Mica lost 80% of its birds in 2000 after the damming of the lake, but then remained stable over our census period (2004–2013). In contrast, the Colta population results from a recent colonisation in the early 2000s, and has experienced an exponential growth since then (annual population multiplication rate: 1.464). The growth of this population is so fast that it must include an important contribution of immigrants. The temporal coincidence between the drop in population size at lake La Mica and the colonisation of lake Colta suggests that the Colta population was founded by immigrants from La Mica. Finally, the absence of current reports of the species at wetlands in Colombia suggests that the species remains at very low numbers, bolstering the shrinkage in northern distribution.

Connecting the trophic dots: responses of an aquatic bird species to variable abundance of macroinvertebrates in northern boreal wetlands

To evaluate variation in abundance of boreal wetland macroinvertebrates and test for effects of this variation on the diet and habitat use of a bird species that consumes aquatic invertebrates (lesser scaup, Aythya affinis), we collected macroinvertebrates and birds and conducted bird surveys (June–August) at two wetland complexes in northwestern Canada and assessed diet composition using an isotopic approach. At both study areas, for macroinvertebrate taxa reported to be key prey items for scaup, biomass varied intra-seasonally and annually, but patterns differed among taxa and between areas. Macroinvertebrate biomass varied strongly across wetlands within study areas, and isotopic mixing models indicated that local heterogeneity in macroinvertebrate biomass was reflected in duckling diets, which also varied across wetlands, indicating a generalist foraging strategy for this species. Wetland habitats used by brood-rearing female scaup had greater amphipod and gastropod biomasses. Our results show that boreal wetland macroinvertebrate abundances vary considerably across coarse and fine spatial scales. Female scaup and their ducklings appear well adapted to exploit this dynamic food resource, but overall productivity of scaup may depend on the abundances of certain taxa, suggesting that conservation efforts should focus on maintaining abundant populations of key wetland invertebrates.

Application of Nested Logitech Model for Ecosystem Services Valuation (Case study: Gavkhony Wetland, Isfahan Province, Iran)

Wetlands as a situ for the growth of native plants, as a habitat for certain species of fish and aquatic birds, and because of their potential economic, cultural and recreational services, are valuable heritage so their protection and conservation is very essential. Mostly due to the absence of wetlands services’ valuation, lack of special regulations, and lack of guarantee for these properties, resources and services of wetlands are not utilized appropriately, and destructed and evacuated in a free and unrestricted fashion, leading to inefficiency in use. The purpose of this study is the economic valuation of Gavkhony wetland ecosystem attributes, estimation of implicit price for attributes, impact assessment of socioeconomic variables such as age, marriage, indigenous, family size and education on willingness to pay (WTP), and analyzing welfare and compensation variation due to variation of hypothetical policy. The approach being used is choice experiment that is a subset of choice modeling procedure and stated preference method. Data were collected from six different choice experiments provided in the questionnaires, which were filled out by 500 randomly selected households in Isfahan and Varzaneh cities in the spring and summer of 2013. Each questionnaire contained 72 hypothetical policies, 36 choice sets, 2442 observations and 7327 rows of data. Nested Logitech models and Hausman-MacFadden test were used in order to estimate the visitors’ WTP for improving attribute levels for Gavkhony wetland. This procedure was used on the basis of multinomial discrete choice analysis of preferences, Lancaster’s theory of value and the theory of random utility function. The Hausman-MacFadden test results showed that cross-elasticity between the first and third options was the same. Thus, these two options were placed in the second nest. The results further showed that the visitors had WTP for preserving forest diversity and vegetation of wetland and its surrounding; preserve of natural habitats and organisms life of wetland (bird, fish and animals); wetland hygiene (preventing industrial and domestic effluent, and water salinity); and increasing the water surface (increasing wetland water inlet). The values estimated for these four aspects correspondingly were 8636, 12584, 11553 and 4740 Rials. Some socio-economic variables such as gender, marriage, age, family expenditure, education and being native had a positive impact on the visitors’ WTP. The surplus welfareresults showed that in 72 hypothetical policies, option 1 had the most positive welfare, and option 5 had the most negative welfare for the users of Govkhony wetland. The surplus welfare results based on WTP estimation provide important tools for policy making. *Corresponding author: Assistant Professor in Economics, Humane science Faculty, University of Ayatollah Borujerdy, Iran, Tel: +98 918 500 3597, E-mail: parviz.jalili@abru.ac.ir, parviz.jalili@gmail.com S. P. Jalili Kamjo et al. ______________________________________________ ECOPERSIA (2016) Vol. 4(1) 1252

Molecular Characterization of Subtype H11N9 Avian Influenza Virus Isolated from Shorebirds in Brazil.

Migratory aquatic birds play an important role in the maintenance and spread of avian influenza viruses (AIV). Many species of aquatic migratory birds tend to use similar migration routes, also known as flyways, which serve as important circuits for the dissemination of AIV. In recent years there has been extensive surveillance of the virus in aquatic birds in the Northern Hemisphere; however in contrast only a few studies have been attempted to detect AIV in wild birds in South America. There are major flyways connecting South America to Central and North America, whereas avian migration routes between South America and the remaining continents are uncommon. As a result, it has been hypothesized that South American AIV strains would be most closely related to the strains from North America than to those from other regions in the world. We characterized the full genome of three AIV subtype H11N9 isolates obtained from ruddy turnstones (Arenaria interpres) on the Amazon coast of Brazil. For all gene segments, all three strains consistently clustered together within evolutionary lineages of AIV that had been previously described from aquatic birds in North America. In particular, the H11N9 isolates were remarkably closely related to AIV strains from shorebirds sampled at the Delaware Bay region, on the Northeastern coast of the USA, more than 5000 km away from where the isolates were retrieved. Additionally, there was also evidence of genetic similarity to AIV strains from ducks and teals from interior USA and Canada. These findings corroborate that migratory flyways of aquatic birds play an important role in determining the genetic structure of AIV in the Western hemisphere, with a strong epidemiological connectivity between North and South America.

GENETIC DIVERSITY AND POPULATION STRUCTURE OF MANDAR BESAR (Porphyrio porphyrio) iNHABITING JAVA WETLANDS

&lt;p&gt;Despite the occurrence of a massive agricultural landscape change in Java, very few reliable studies evaluate its genetic consequence for impacted wildlife species. This study reported the genetic diversity of the Mandar besar (Porphyrio porphyrio) in the modified landscape of Java as a backdrop for such an evaluation. Aim of this study was to estimate genetic diversity and genetic structure of the species. I collected eighty-eight blood samples from five a-priory populations (Demak, Jombor, Kendal, Pagak, and Nawan) and genotyped them at ten selected microsatellite loci to estimate allelic richness (R) and expected heterozygosity (He), fixation index (FST) and genetic clusters (K). DNA was isolated using a commercial kit (Invitrogen) and amplified using touch-down polymerase-chain-reaction technique. Allele length was estimated using an automatic sequencer. Pre-analysis showed that all selected loci have null alleles frequency less than 0.2, successful amplification rate more than 80%, no significant linkage between loci and no deviation from HWE. Further analysis employing GDA and FSTAT showed that Demak population has richest genetic diversity in term of R, meanwhile Jombor was the poorest population. Analysis of population structure employing FSTAT and STRUCTURE showed that the population was likely structured into four subpopulations, as showed by FST (0.085; P&amp;lt;0.05) and K=4 (ln probability -1725.2+3.92). This study might reveal that genetic diversity and population structure of Mandar besar in Java were still in common level as compared to other aquatic bird species.&lt;/p&gt;&lt;p&gt;&lt;br /&gt;&lt;strong&gt;Keywords &lt;/strong&gt;:Swamphen, bird, richness, genetic, wetlands&lt;/p&gt;

SPECIES DIVERSITY OF WETLAND BIRDS IN DRY ZONE SEASONAL RESERVOIRS IN SRI LANKA

The quantification of species diversity is essential in several aspects of ecology, including conservation biology, and as an indicator of the well-being of ecological systems. However, species diversity of the wetland birds in the seasonal reservoirs in the dry zone of Sri Lanka has received very little attention. In the present study, an attempt was made to determine the species diversity of wetland birds of 20 seasonal reservoirs in Anuradhapura and Monaragala Districts during both migratory and non-migratory seasons. A total of 46 species of aquatic birds belonging to 17 families (represent 7 orders) were recorded during the present study in selected seasonal reservoirs in the two districts. Overall, both bird species richness and abundance were higher in Anuradhapura district compared to Monaragala District. However, there were more bird species in both districts during migratory seasons. We have detected significant seasonal differences in species diversity estimated by both the Shannon-Wiener Index (F=3.926; P &lt;0.1) and Simpson’s Index (F=3.718; P &lt;0.1). This suggests that there was a significantly higher diversity of wetland birds during the migratory season. Species-area relationships suggested that the species richness of wetland birds associated with seasonal reservoirs would increase as the reservoir size increases. However, these relationships represented weak correlations (R2 range = 0.331–0.645). Overall our study indicates that seasonal reservoirs in Sri Lanka support a diverse community of wetland birds and provide a strong example for a case of enhancement of biological diversity through human activities by creating artificial habitats.

INFLUENZA DETECTED IN Macronectes giganteus IN TWO ISLANDS OF SOUTH SHETLANDS, ANTARCTICA

Influenza A virus was detected in different species of birds and migratory aquatic birds. They are the main reservoir of the virus. In this research we detected the first Influenza A virus in Southern Giant Petrel in an Antarctic region. The results represent 0.33% of the samples collected in two breeding areas of the species. Some factors can explain the introduction of these pathogens and diseases in Antarctica, such as bird's migratory behavior and the remains of the virus in cold waters.

Oxidative stress in songbirds exposed to dietary methylmercury.

Long-term, sublethal methylmercury exposure can cause reproductive depression, immune suppression, endocrine disruption and other problems in birds. We used two biomarkers to detect oxidative stress in livers of zebra finches (Taeniopygia guttata) developmentally exposed to sublethal levels of dietary methylmercury (0.0, 0.3, 0.6, 1.2, or 2.4μg/g wet weight in diet). Our findings indicate that young adult finches exposed to environmentally relevant concentrations of mercury in ovo and through their diets, exhibited oxidative stress in their livers. We measured the ratio of the antioxidant glutathione in its reduced form (GSH) versus its oxidized form (GSSG) and the activity of the superoxide dismutase (SOD) enzyme suite. Blood total mercury served as a proxy for liver mercury concentration, and was on average 8.4 times the dietary dose (e.g., birds consuming 0.6μg/g had blood mercury levels of ~5μg/g on a wet weight basis). Consistent with what is known from large, aquatic bird species, there was a significant, negative relationship between GSH/GSSG ratios and tissue mercury concentrations, which is indicative of oxidative stress. This relationship was driven by a significant increase in the oxidized glutathione in the livers of birds with higher blood mercury levels. SOD activity was also found to have a significant, negative relationship with blood mercury.

Brominated flame retardant trends in aquatic birds from the Salish Sea region of the west coast of North America, including a mini-review of recent trends in marine and estuarine birds

Polybrominated diphenyl ethers (PBDEs) increased in many matrices during the 1990s and early 2000s. Since voluntary restrictions and regulations on PBDEs were implemented in North America circa early 2000s, decreases in PBDEs have occurred in many of these same matrices. To examine temporal trends in the North Pacific, we retrospectively analysed PBDEs and eight non-PBDE flame retardants (FR) in eggs of two aquatic bird species, great blue herons, Ardea herodias, and double-crested cormorants, Phalacrocorax auritus, collected along the British Columbia coast, Canada from 1979 to 2012. Increasing PBDE concentrations were observed in both species followed by significant decreases post-2000 for all dominant congeners and ΣPBDE. Non-PBDE FRs were generally undetected in cormorant eggs, or detected at very low levels in heron eggs, except for hexabromocyclododecane (HBCDD). HBCDD, currently unregulated in North America, was not detected in early sampling years; however low concentrations were observed in both species in recent sampling years (2003–2012). Dietary tracers (δ13C and δ15N) did not change significantly over time, indicating that temporal changes in PBDEs are likely caused by implemented regulations. A comparison with recently published temporal trends of ΣPBDE in marine birds from North America and Europe is given.

Freshwater inflows and seasonal forcing strongly influence macrofaunal assemblages in Mediterranean coastal lagoons

Coastal lagoons of the Ebro Delta (Catalonia, Spain) are part of the Ebro Delta Natural Park managed by regional government authorities. Coastal lagoons have persistently received freshwater inputs from the Ebro River from May to November that have altered their natural ecology and hydrological cycle. In this study, we evaluate the seasonal effect of contrasting salinity regimes (polyhaline in the Tancada lagoon, mesohaline in the Encanyissada and oligohaline in the Clot lagoon) on the composition, abundance, species richness, alpha diversity and biomass of benthic macrofauna communities, and we assess the relative contribution of local environmental variables to the observed patterns. Additional sampling was conducted in the largest lagoon (Encanyissada) in order to assess variability at lower spatial scale. At both spatial scales (i.e., among-lagoon and within-lagoon), species richness and diversity tended to increase at higher salinities, particularly in summer. At the assemblage level, significantly different groupings were also found among lagoons and among zones of the Encanyissada lagoon, with more distinctive differences also in summer. Environmental factors accounted for up to 56–60% of the variation in macrofaunal assemblages at both spatial scales, with salinity and temperature accounting for the largest contributions (approx. 14% and 10%, respectively), whereas biomass was mostly controlled by temperature and nutrients. Distinctive oxygen and organic matter levels across the lagoons were also associated with the freshwater influx and displayed significant contributions to observed patterns. Our study shows that the low salinity regime and/or other factors related to long-term inputs of freshwater shape the community of macrofauna within the lagoons, a central trophic resource for most of the local species of fish and aquatic birds. Restoration of these systems to their natural hydrological functioning without further inputs of freshwater and higher marine connectivity is suggested as the more appropriate management.

Influenza A virus prevalence and its implications on survival in mallard

Avian influenza is an infectious viral disease of birds caused by type A strains of the influenza virus. Aquatic bird species have adapted to carry and transmit a wide range of influenza strains in nature. Here we report the results of a 4.5-year monitoring program forOrthomyxovirusprevalence in a population of wild mallard (Anas plathyrynchos) in northwestern Italy. To determine whetherOrthomyxovirusprevalence affects survival, we used MARK software to compare the survival of AIV-positive versus AIV-negative birds. Prevalence rates and variance were estimated using inverse sampling method. The prevalence rate of influenza A virus was 4.3% (SE 0.00116) and lifespan was shorter (29.8%) for the young infected birds than for the young non-infected birds.