Pesticide poisoning events in wild birds in Korea from 1998 to 2002

We describe cases of pesticide poisoning of wild birds diagnosed at the National Veterinary Research and Quarantine Service (Kyunggi, Korea) from 1998 to 2002. Forty-one mortality events (759 birds) of 87 incidents (2,464 birds) investigated were associated with pesticide poisoning, and six organophosphates or carbamates were identified as being responsible for the poisoning. Phosphamidon was most frequently identified as the cause of poisoning, accounting for 23 mortality events. Other pesticides identified as poisons for birds were organophosphates monocrotophus, fenthion, parathion, EPN, and diazinon, and the carbamate carbofuran. Pesticide poisoning is a problem in wild birds in Korea.     

Use of molecular markers for species identification of Korean Perkinsus sp. isolated from Manila clams Ruditapes philippinarum

Perkinsus is the pathogen responsible for mass mortality of the Manila clam Ruditapes philippinarum. Perkinsus sp. isolated from Manila clams collected in Korean waters was assayed by polymerase chain reaction (PCR) to determine its phylogenetic affinity with other congeneric species. Regions of rRNA of Perkinsus sp. isolated from clam haemolymph were cloned and sequenced. Sequences of a non-transcribed spacer (NTS), internal transcribed spacers (ITS 1, 2) and 5.8S rRNA genes were compared to those available from other Perkinsus species. The NTS sequence of Korean Perkinsus was approximately 99.9 to 100% similar to that of P. atlanticus and 98.06 to 98.15% and 73.05 to 73.14% similar to those of P. olseni and P. marinus, respectively. The ITS 1, 5.8S rRNA and ITS 2 sequences of Korean Perkinsus showed 100% similarity to P. atlanticus and Perkinsus sp. reported from Japan. The ITS-5.8S rRNA sequences of Korean Perkinsus were 99.86 and 93.73% similar to those of P. olseni and P. marinus, respectively. The sporulation pattern and morphology of the Korean Perkinsus were very similar to those of P. atlanticus. Our data suggest that the Perkinsus sp. isolated from clams in Korean waters is P. atlanticus, which is currently synonymous with P. olseni reported from Australia. By considering that P. olseni has taxonomic priority, Korean Perkinsus sp. is accepted as P. olseni (atlanticus).     

The role of Cytograpsus angulatus (Crustacea; Brachyura) in the life cycles of Microphallus szidati (Digenea; Microphallidae) and Falsifilicollis chasmagnathi (Acanthocephala; Filicollidae): various aspects of their ecological parasitology

Based on a study of the larvae from two helminth species parasitizing the crab Cyrtograpsus angulatus Dana, 1851 (Microphallus szidati Martorelli, 1986 and Falsifilicollis chasmagnathi Holcman-Spector et al., 1977), from Mar chiquita lagoom (Argentina) together with the analyses of their life cycles and rates of prevalence, intensity and association coefficient (compared in definitive and intermediate host) the following conclusions have been reached: a) C. angulatus suns to be an excellent intermediate host in the life-cycles of the studied helminths; b) the size of the crabs and the occurrence of natural amputations in the females (Spivak & Politis, in press) appeared correlated with prevalence; c) in the studied crabs the prevalence for F. chasmagnathi is higher in males than in females; d) the intensity did not appear correlated with size and sex of the intermediate host; e) M. szidati and F. chasmagnathi are closely associated with the intermediate host; f) C. angulatus and Himantopus melanurus Vieillot, 1817 (Aves; Recurvirostridae) are reported as new intermediate and definitive hosts, respectively, for F. chasmagnathi; g) Chasmagnathus granulata Dana, 1851 (Crustacea; Brachyura) is reported as a new intermediate host for M. szidati.     

Allopaternal care in the redlip blenny

Territorial male Ophioblennius atlanticus atlanticus were found to switch to experimentally deserted nests of other males and adopt their fry. This alloparental care appears to aid in     

Hailstorms as a cause of mass mortality of Swainson's hawks in their wintering grounds

We describe a mass mortality event of wintering Swainson's hawks (SH, Buteo swainsoni) in central Argentina during November 2003. One hundred thirteen SH were found dead as a consequence of a single hailstorm. In addition, 14 hawks with severe injuries were recovered alive, but only 10 of these survived 1 wk later. Another 45 dead birds of 11 species were collected in the area. Interviews with local land-owners conducted in other areas of the SH wintering grounds provided further evidence of past hailstorm-related mortality involving SH, suggesting that such events commonly occur in the Argentine Pampas. This potential cause of mass mortality of SH wintering in agricultural areas of Argentina may be significant when added to the increased mortality associated with poisoning events during the last decade.     

First record in South America of Didymosulcus palati and Didymosulcus philobranchiarca (Digenea, Didymozoidae) with new hosts records and pathological alterations

Two species of Didymozoidae, Didymosulcus palati (Yamaguti 1970) and Didymosulcus philobranchiarca (Yamaguti 1970) were reported for the first time in South America, Atlantic Ocean, parasitizing three different tuna species from the coast of Rio de Janeiro, Brazil: Thunnus atlanticus (Lesson), Thunnus albacares (Bonnaterre) and Thunnus obesus (Lowe). Pairs of D. philobranchiarca were found on gill arches of T. albacares and T. obesus, in longitudinal rows of yellow cysts located inside grooves in the hard denticle palate (new site) of the three hosts species studied, and as disperse groups of cysts in the operculum (new site) and gill arches of T. atlanticus (new host record). D. palati occurred as disperse groups of encysted worm pairs in the gill arches of T. albacares and T. obesus and in gill arches and operculum of T. atlanticus (new host record). The pathological alterations induced by D. philobranchiarca in the palate of T. atlanticus are described for the first time. Original measurements and figures are presented.     

Avian wildlife mortality events due to salmonellosis in the United States, 1985-2004

Infection with Salmonella spp. has long been recognized in avian wildlife, although its significance in causing avian mortality, and its zoonotic risk, is not well understood. This study evaluates the role of Salmonella spp. in wild bird mortality events in the United States from 1985 through 2004. Analyses were performed to calculate the frequency of these events and the proportional mortality by species, year, month, state, and region. Salmonellosis was a significant contributor to mortality in many species of birds; particularly in passerines, for which 21.5% of all mortality events involved salmonellosis. The proportional mortality averaged a 12% annual increase over the 20-yr period, with seasonal peaks in January and April. Increased salmonellosis-related mortality in New England, Southeastern, and Mountain-Prairie states was identified. Based on the results of this study, salmonellosis can be considered an important zoonotic disease of wild birds.     

Parasitism by the protozoan Perkinsus atlanticus favours the development of opportunistic infections

It has been suggested that opportunistic pathogens could contribute to the mortality of Perkinsus atlanticus-infected clams. Examination of Tapes semidecussatus clams from the northern Mediterranean coast of Spain revealed that while 86% of the clams heavily infected with P. atlanticus were co-infected by bacteria and/or viruses, neither non-infected nor lightly P. atlanticus-infected specimens had bacterial or viral infections. The bacteria, which had a Gram-negative cell wall, were always located in the apical pole of gill epithelial cells and enclosed within membranous compartments. Bacteria-containing cells were hypertrophied and showed dysplasia with loss of cilia and microvilli. The viruses shared ultrastructural, morphologic and cytopathic characteristics of a polyomavirus. Viral particles with icosahedral symmetry were found in both the cytoplasm and the nucleus of numerous cell types. Virus-infected cells showed severe alterations, including hypertrophy, reduction of the intracellular compartments and extrusion of the nuclear envelope. Moreover, gill epithelial cells showed disorganization and swelling of the apical region, which affected the ciliary structure. Our findings show that P. atlanticus parasitism favours the development of opportunistic infections which have detrimental effects in this clam population.     

Continuous in vitro culture of the carpet shell clam Tapes decussatus protozoan parasite Perkinsus atlanticus

Continuous in vitro cultures of the clam Tapes decussatus parasite Perkinsus atlanticus were established from infected gill fragments, infected haemolymph and parasite hypnospores isolated from infected gill fragments following incubation in Ray's fluid thioglycollate medium (RFTM). No continuous cultures could be initiated from P. atlanticus zoospores. Cultures initiated from hypnospores yielded the highest percentage of continuous cultures (100%, 6/6), followed by cultures initiated from gill fragments (93%, 43/46) and from haemolymph (30%, 3/10). Failures to establish continuous cultures were due to microbial contamination. The source of parasite influenced the success rate, the time taken to establish cultures and the size of cultured cells. In vitro proliferation of parasite cells was mainly by vegetative multiplication. Zoosporulation, yielding motile biflagellated zoospores, was observed at a low frequency (< 1% of dividing cells) in every culture. Morphology of cultured cells examined with light and transmission electron microscopy corresponded to that of P. atlanticus found in clam tissues. Cultured cells enlarged in RFTM and stained blue-black with Lugol's solution, which are characteristics of the Perkinsus species cells. DNA sequences of the internal transcribed spacer (ITS) region of the ribosomal RNA gene complex matched those of P. atlanticus. All cultures were established in a medium designated JL-ODRP-2A that was similar in composition to the culture medium JL-ODRP-1 originally used to propagate Perkinsus marinus in vitro. Proliferation of P. atlanticus in vitro could be supported by the commercial culture medium (1:2 v/v) DME:Ham's F-12 with fetuin.     

Expansion of an exotic species and concomitant disease outbreaks: pigeon paramyxovirus in free-ranging Eurasian collared doves

Eurasian collared doves (Streptopelia decaocto) have expanded their range across the United States since their introduction several decades ago. Recent mortality events in Eurasian collared doves in Arizona and Montana, USA, during the winter of 2009-2010 were the result of pigeon paramyxovirus (PPMV), a novel disease agent. The first instance of mortality by this emerging infectious disease in this species occurred in Florida in 2001 with subsequent disease events in 2006 and 2008. Full diagnostic necropsies were performed on carcasses from the three states. PPMV was identified by RT-PCR and virus isolation and was sequenced to the VIb genotype of avian paramyxovirus-1 (APMV). Other APMVs are common in a variety of free-ranging birds, but concern is warranted because of the potential for commingling of this species with native birds, virus evolution, and threats to domestic poultry. Improved surveillance for wildlife mortality events and efforts to prevent introduction of non-native animals could reduce the threat of introducing new pathogens.     

Fine structure of Perkinsus atlanticus n. sp. (Apicomplexa, Perkinsea) parasite of the clam Ruditapes decussatus from Portugal

A new apicomplexan species, Perkinsus atlanticus, is described from gill filaments of the clam Ruditapes decussatus (Bivalvia) from Portugal, where it causes great mortality. The zoospores differ from those of other species of Perkinsus in size and shape, dimensions, insertion of the 2 flagella, and in the identity of the host. On the other hand, the life cycle stages showed some ultrastructural differences compared with Perkinsus marinus, the only species previously studied in detail. When the clams were parasitized heavily, ultrastructurally similar life cycle stages were found in foot and mantle tissues.     

An eco-morphological explanation of individual variability in the shape of the fish otolith: comparison of the otolith of Hoplostethus atlanticus with other species by depth

Variation in otolith shape (otolith polymorphism) in Hoplostethus atlanticus, Hoplostethus mediterraneus, Paratrichichthys trailli, Pagrus major and Trachurus murphyi , quantified using principal components analysis based on Fourier transform decompositions of outlines of otolith shape, was particularly high among the samples of H. atlanticus from the North Atlantic, New Zealand, Australia and Namibia. The scatter was uniform, however, and did not show any significant differences among regions. The implication drawn from the high variability in otolith shape of H. atlanticus was that otolith shape polymorphism was maintained by some form of balancing selection across many small local environments which may result in k-selection with consequent poor response by H. atlanticus to maximum sustainable yield harvesting strategies. The variation in otolith shape defined by the otolith morphospace of the five species that were measured, showed a decreasing trend in scatter (i.e. decreasing complexity of shape) proceeding from the species with the deepest habitat ( H. atlanticus ) to the most shallow ( T. murphyi ).     

Characterization of the ribosomal RNA locus of Perkinsus atlanticus and development of a polymerase chain reaction-based diagnostic assay

The rRNA locus of Perkinsus atlanticus from the clam Ruditapes decussatus cultivated on the Atlantic coast of Spain was cloned and sequenced. Sequences of the internal transcribed spacer (ITS) from the rRNA locus were compared to sequences reported earlier for a P. atlanticus isolate from Portugal and to those from other Perkinsus species. The ITS I sequence of the Spanish P. atlanticus isolate was identical to the Portuguese P. atlanticus sequence and had 76.6% identity to the ITS1 of Perkinsus marinus. The ITS2 sequence had 99.7% identity to the Portuguese P. atlanticus ITS2, 92.5% identity to the P. marinus ITS2, and 99.5% identity to the Perkinsus olseni ITS2. We report for first the time the small subunit (SSU) and nontranscribed spacer (NTS) of P. atlanticus. The P. atlanticus SSU sequence was 99.6% identical to that of an unidentified Perkinsus species from the Australian clam Anadara trapezia and 98.0% identical to that of P. marinus. Further, our results support the proposal that P. atlanticus, P. olseni, and the Perkinsus sp. from A. trapezia constitute a subgroup of Perkinsus species distributed in the Pacific and eastern Atlantic, different from P. marinus that is distributed along the western edge of the Atlantic. Based on the NTS sequence of P. atlanticus from Spain and the differences with P. marinus NTS (62.2% identity), we developed a polymerase chain reaction (PCR)-based diagnostic assay with a lowest limit of detection of 0.01 amol of cloned NTS DNA as assessed on ethidium bromide-stained agarose gels. Specificity of the PCR-based assay was tested with samples from the clams R. decussatus, Ruditapes philippinarum, and Venerupis pullastra collected in P. atlanticus-enzootic areas of Spain. The specificity and sensitivity demonstrated for this NTS-based PCR assay validate its use as a tool for assessment of P. atlanticus in molluscs.     

Development of an in vitro clonal culture and characterization of the rRNA gene cluster of Perkinsus atlanticus,a protistan parasite of the clam Tapes decussatus

Perkinsus atlanticus cultures were established either with trophozoites isolated from fresh gills, with hypnospores isolated from tissues incubated in fluid thioglycollate medium, or directly from infected hemocytes of carpet shell clams Tapes decussatus from Algarve (Southern Portugal), using a culture medium and conditions optimized for Perkinsus marinus. Perkinsus atlanticus isolates were cloned by limiting dilution, and their identity unequivocally established by PCR-based species-specific diagnostic assays, and by sequencing the complete rRNA gene cluster. The rRNA gene cluster is 7.5-kb in length including 5S, IGS, SSU, ITS1, 5.8S, ITS2, LSU, and an inter-cluster spacer. rDNA sequences of the P. atlanticus clone were between 98.3-100% identical to P. atlanticus sequences previously obtained from clam tissue (non-clonal) isolates. Based on the IGS sequences available from Perkinsus species, a set of primers was designed to amplify P. atlanticus and the two clonally cultured Perkinsus species (P. marinus and P. andrewsi) currently available from a recognized repository. This Perkinsus "genus-specific" PCR-based assay complements the species-specific assays developed earlier and strengthen the detection of Perkinsus species for which specific detection assays are not yet available.     

Avian malaria Plasmodium relictum in native Hawaiian forest birds: epizootiology and demographic impacts on ‵apapane Himatione sanguinea

The role of introduced avian malaria Plasmodium relictum in the decline and extinction of native Hawaiian forest birds has become a classic example of the potential effect of invasive diseases on biological diversity of naïve populations. However, empirical evidence describing the impact of avian malaria on fitness of Hawai‵i's endemic forest birds is limited, making it difficult to determine the importance of disease among the suite of potential limiting factors affecting the distribution and abundance of this threatened avifauna. We combined epidemiological force‐of‐infection with multistate capture––recapture models to evaluate a 7‐year longitudinal study of avian malaria in ‵apapane, a relatively common native honeycreeper within mid‐elevation Hawaiian forests. We found that malaria transmission was seasonal in this mid‐elevation forest; transmission peaked during fall and during some years produced epizootic mortality events. Estimated annual mortality of hatch‐year birds typically exceeded 50% and mortality of adults exceeded 25% during epizootics. The substantial impact of avian malaria on this relatively common native species demonstrates the key role this disease has played in the decline and extinction of Hawaiian forest birds.     

Waterbird mortality in hypersaline environments: the Wyoming trona ponds

Each year hundreds of salt-encrusted waterbirds, mainly Eared Grebes (Podiceps nigricollis Brehm) die at evaporation ponds of the trona (soda ash) industry in southwestern Wyoming. Clinical investigations attributed the mortality to sodium toxicity because high levels of sodium were found in brains of grebes salvaged from the ponds. This was puzzling because natural history information shows that this species resides in saline and hypersaline environments for most of the year. In addition, field observations gave no indication that grebes at the ponds were ingesting salt or salt crystals. Further, the salt glands were not hypertrophied and gavage experiments showed that healthy birds were able to ingest trona pond water without ill effect. Carcasses immersed in pond water, however, attained brain sodium levels far exceeding those considered toxic within a few hours, indicating that the high levels considered as causal probably resulted from post-mortem events. We attribute the mortality to complications of salt encrustation, notably impaired thermoregulation. Other purported cases of sodium toxicity involving encrusted birds at industrial ponds or hypersaline situations may have a similar etiology.     

The West Nile virus: its recent emergence in North America

West Nile fever emerged in New York in the summer of 1999 when seven people, several horses and thousands of wild birds died. It was soon established that the human disease and the mortality of birds were related. Continued surveillance detected West Nile virus in mosquitoes, birds, horses, small mammals, bats and humans, and has shown its spread to several northeastern states. These events confirm the establishment of West Nile virus endemically in the United States.     

Mass Stranding of Marine Birds Caused by a Surfactant-Producing Red Tide

In November-December 2007 a widespread seabird mortality event occurred in Monterey Bay, California, USA, coincident with a massive red tide caused by the dinoflagellate Akashiwo sanguinea. Affected birds had a slimy yellow-green material on their feathers, which were saturated with water, and they were severely hypothermic. We determined that foam containing surfactant-like proteins, derived from organic matter of the red tide, coated their feathers and neutralized natural water repellency and insulation. No evidence of exposure to petroleum or other oils or biotoxins were found. This is the first documented case of its kind, but previous similar events may have gone undetected. The frequency and amplitude of red tides have increased in Monterey Bay since 2004, suggesting that impacts on wintering marine birds may continue or increase.     

A male sexually dimorphic trait provides antimicrobials to eggs in blenny fish

Predation and microbial infections are the major causes of natural mortality for early life stages of oviparous species. The parental traits reducing the effects of predation are rather well described, whereas antimicrobial mechanisms enhancing offspring survival are largely unexplored. In this paper, we report that a male sexually dimorphic trait, the anal glands, of the redlip blenny (Ophioblennius atlanticus atlanticus) and the peacock blenny (Salaria pavo), two fish species with paternal egg care, produce a mucus enriched with antimicrobial substances. Histological and histochemical analyses showed that the anal glands of these species are characterized by the massive presence of mucus-secreting cells. Anal gland extracts, from both the hydrophilic and the hydrophobic protein fraction, exhibited a lysozyme-like activity. Field observations demonstrated that redlip blenny males, while performing egg care, rub the anal region over the nest internal surface, probably facilitating the transfer of mucus to eggs. These results strongly indicate that this sexually dimorphic trait is involved in egg defence against microbial infections.     

Forest bird mortality and baiting practices in New?Zealand aerial 1080 operations from 1986 to 2009

We collated 48 surveys of individually banded birds or birds fitted with radio transmitters that were checked before and after 1080 poison (sodium fluoroacetate) baits were aerially distributed to control brushtail possums (Trichosurus vulpecula) in New?Zealand forests. The surveys were associated with 34 pest control operations from 1986 to 2009 and covered 13 native bird species, of which four were kiwi (Apteryx spp.). Sample sizes ranged from 1 to 46 birds (median 15). In 12 cases a sample of 1 to 42 birds (median 13) was surveyed in an untreated area at the same time. In total, 748 birds were checked before and after operations and 48 birds disappeared or were found dead. In non-treatment areas, 193 birds were checked and four died. Surveys of kiwi, whio (Hymenolaimus malacorhynchos), kaka (Nestor meridionalis) and kokako (Callaeas cinerea) were grouped for meta-analyses. The 95% pooled upper confidence bounds for the point estimate of zero mortality were each less than 4% for kiwi, kaka and kokako indicating only a small risk of mortality during 1080 pest control operations. Prefeeding with non-toxic baits increased from 22% (1998?1999) to 79% (2007?2008) in 322 operations on public conservation lands but was used in only 9 (26%) of the operations during which individually marked birds were monitored. We caution that failure to observe bird deaths in small samples may lead to weak inference about zero mortality across a population, most surveys in the review did not involve prefeeding, and that 11 native bird species for which deaths were reported after 1080 operations have not been studied.