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1.
Proc Natl Acad Sci U S A ; 119(37): e2204847119, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36067296

RESUMO

Birds perform astounding aerial maneuvers by actuating their shoulder, elbow, and wrist joints to morph their wing shape. This maneuverability is desirable for similar-sized uncrewed aerial vehicles (UAVs) and can be analyzed through the lens of dynamic flight stability. Quantifying avian dynamic stability is challenging as it is dictated by aerodynamics and inertia, which must both account for birds' complex and variable morphology. To date, avian dynamic stability across flight conditions remains largely unknown. Here, we fill this gap by quantifying how a gull can use wing morphing to adjust its longitudinal dynamic response. We found that it was necessary to adjust the shoulder angle to achieve trimmed flight and that most trimmed configurations were longitudinally stable except for configurations with high wrist angles. Our results showed that as flight speed increases, the gull could fold or sweep its wings backward to trim. Further, a trimmed gull can use its wing joints to control the frequencies and damping ratios of the longitudinal oscillatory modes. We found a more damped phugoid mode than similar-sized UAVs, possibly reducing speed sensitivity to perturbations, such as gusts. Although most configurations had controllable short-period flying qualities, the heavily damped phugoid mode indicates a sluggish response to control inputs, which may be overcome while maneuvering by morphing into an unstable flight configuration. Our study shows that gulls use their shoulder, wrist, and elbow joints to negotiate trade-offs in stability and control and points the way forward for designing UAVs with avian-like maneuverability.


Assuntos
Charadriiformes , Voo Animal , Asas de Animais , Animais , Charadriiformes/fisiologia , Voo Animal/fisiologia , Asas de Animais/anatomia & histologia , Asas de Animais/fisiologia
2.
Zootaxa ; 5175(1): 1-30, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36095378

RESUMO

We describe Lepidotrigona thenzawlensis sp. n., L. rajithae sp. n., L. amruthae sp. n. all from Thenzawl, Mizoram and L. sikkimensis sp. n. from Mamley, Sikkim with associated female and male bees and with a brief note on the nest structure of the former three species. These new species belong to the ventralis species group with body and forewing lengths less than 5 mm in females. These four species are different from the holotype of L. arcifera (from the ventralis group), the only known species from India, in morphometry and ratio of interocellar to ocellocular distance, scape length to eye length, hind tibial length to forewing diagonal length, and hind basitarsus width to hind tibial width are greater than those in L. arcifera. The new species also differ from other species of the ventralis group (L. arcifera, L. flavibasis, L. ventralis, L. satun and L. doipaensis) of the Indo-Malayan region in morphometry, pilosity, structure of male metasomal sterna and male genitalia. Each new species is distinct and can be differentiated from each other based on the structure of male metasomal sterna 4, 5 and 6 as well as genitalia. The brood cells in L. thenzawlensis and L. rajithae were arranged in single-cell thick multi-layered combs. The discovery of these four new species increases the number of species of the genus Lepidotrigona from one to five from India.


Assuntos
Charadriiformes , Himenópteros , Animais , Abelhas , Feminino , Genitália , Masculino
3.
Zootaxa ; 5178(1): 26-40, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36095744

RESUMO

The stilt-legged fly (Diptera, Micropezidae) fauna of South Korea is reviewed, including a description of a new species, Rainieria tenebrosa Kim and Lee sp. nov., and 4 new distributional records (Micropezinae: Micropeza soosi Ozerov; Taeniapterinae: Rainieria triseta Li, Liu Yang, Mimegralla suzukiana (Matsumura); Calobatinae: Compsobata dentigera (Loew)). Detailed information on the biology of the new species is presented. Keys to the Palearctic species of Rainieria and the Korean Micropezidae species are provided.


Assuntos
Charadriiformes , Dípteros , Distribuição Animal , Animais , República da Coreia
4.
Harmful Algae ; 117: 102270, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35944958

RESUMO

Harmful algal blooms produce biotoxins that can injure or kill fish, wildlife, and humans. These blooms occur naturally but have intensified in many locations globally due to recent climatic changes, including ocean warming. Such changes are especially pronounced in northern regions, where the effects of paralytic shellfish toxins (PSTs) on marine wildlife are of growing concern. In Alaska, seabird mortality events have increased in frequency, magnitude, and duration since 2015 alongside anomalously high ocean temperatures. Although starvation has been implicated as the apparent cause of death in many of these die-offs, saxitoxin (STX) and other PSTs have been identified as possible contributing factors. Here, we describe a mortality event at a nesting colony of Arctic Terns (Sterna paradisaea) near Juneau, Alaska in 2019 and report elevated concentrations of PSTs in bird, forage fish, and mussel samples. Concentrations of STX and other PSTs in tern tissues (2.5-51.2 µg 100g-1 STX-equivalents [STX-eq]) were of similar magnitude to those reported from other PST-induced bird die-offs. We documented high PST concentrations in blue mussels (>11,000 µg 100g-1 STX-eq; Mytilus edulis spp.) collected from nearby beaches, as well as in forage fish (up to 494 µg 100g-1 STX-eq) retrieved from Arctic Tern nests, thereby providing direct evidence of PST exposure via the terns' prey. At maximum concentrations measured in this study, a single 5 g Pacific Sand Lance (Ammodytes personatus) could exceed the median lethal STX dose (LD50) currently estimated for birds, offering strong support for PSTs as a likely source of tern mortality. In addition to describing this localized bird mortality event, we used existing energetics data from adult and nestling Arctic Terns to calculate estimated cumulative daily PST exposure based on ecologically relevant concentrations in forage fish. Our estimates revealed potentially lethal levels of PST exposure even at relatively low (≤30 ug 100g-1 STX-eq) toxin concentrations in prey. These findings suggest that PSTs present a significant hazard to Arctic Terns and other northern seabirds and should be included in future investigations of avian mortality events as well as assessments of population health.


Assuntos
Charadriiformes , Alaska , Animais , Aves , Peixes , Humanos , Saxitoxina , Alimentos Marinhos , Frutos do Mar/análise
5.
Dis Aquat Organ ; 150: 161-167, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35979990

RESUMO

Conservation of endangered animal species is a major task of zoos. Husbandry and breeding of Atlantic puffins Fratercula arctica in captivity is challenging. In 2019, the entire chick population (n = 4 chicks) in Berne Animal Park's Atlantic puffin colony (Bern, Switzerland) died within 7 d. Due to supply constraints, the chicks had been fed with wild-caught European minnows Phoxinus phoxinus. At necropsy, the main pathological finding in all deceased puffin chicks was a multifocal, moderate to severe subacute heterophilic and granulomatous enteritis with intralesional adult trematodes and eggs. Metacercariae surrounded by few necrotic cells and scattered macrophages were found in the brain and spinal cord of the food fish. Additional microbiological analyses of both the puffin chicks and fish were unremarkable. Diplostomum phoxini DNA could be identified in formalin-fixed paraffin-embedded tissue from the small intestine of all puffin chicks and European minnows following PCR and sequencing of the 18S ribosomal RNA gene and the internal transcribed spacer (ITS1) region. This report illustrates the importance of intensive health checks of food fish for animal species kept in captivity.


Assuntos
Charadriiformes , Cyprinidae , Trematódeos , Animais , Encéfalo , Ingestão de Alimentos
6.
PLoS One ; 17(8): e0270957, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35925977

RESUMO

Determining the dynamics of where and when individuals occur is necessary to understand population declines and identify critical areas for populations of conservation concern. However, there are few examples where a spatially and temporally explicit model has been used to evaluate the migratory dynamics of a bird population across its entire annual cycle. We used geolocator-derived migration tracks of 84 Dunlin (Calidris alpina) on the East Asian-Australasian Flyway (EAAF) to construct a migratory network describing annual subspecies-specific migration patterns in space and time. We found that Dunlin subspecies exhibited unique patterns of spatial and temporal flyway use. Spatially, C. a. arcticola predominated in regions along the eastern edge of the flyway (e.g., western Alaska and central Japan), whereas C. a. sakhalina predominated in regions along the western edge of the flyway (e.g., N China and inland China). No individual Dunlin that wintered in Japan also wintered in the Yellow Sea, China seas, or inland China, and vice-versa. However, similar proportions of the 4 subspecies used many of the same regions at the center of the flyway (e.g., N Sakhalin Island and the Yellow Sea). Temporally, Dunlin subspecies staggered their south migrations and exhibited little temporal overlap among subspecies within shared migration regions. In contrast, Dunlin subspecies migrated simultaneously during north migration. South migration was also characterized by individuals stopping more often and for more days than during north migration. Taken together, these spatial-temporal migration dynamics indicate Dunlin subspecies may be differentially affected by regional habitat change and population declines according to where and when they occur. We suggest that the migration dynamics presented here are useful for guiding on-the-ground survey efforts to quantify subspecies' use of specific sites, and to estimate subspecies' population sizes and long-term trends. Such studies would significantly advance our understanding of Dunlin space-time dynamics and the coordination of Dunlin conservation actions across the EAAF.


Assuntos
Migração Animal , Charadriiformes , Animais , Aves , Ecossistema , Humanos , Estações do Ano
7.
Environ Sci Technol ; 56(17): 12097-12105, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-35946869

RESUMO

Marine predators are monitored as indicators of pollution, but such trends can be complicated by variation in diet. Glaucous-winged gulls (Larus glaucescens) have experienced a dietary shift over the past century, from mainly marine to including more terrestrial/freshwater inputs, with unknown impacts on mercury (Hg) trends. We examined 109-year trends in total mercury (THg) and methylmercury (MeHg) concentrations in glaucous-winged gull feathers (1887-1996) from the Salish Sea. Adult flank feathers had higher MeHg concentrations than immature feathers, and males head feathers had higher THg concentrations than females. Overall, we found no evidence of a trend in feather MeHg or THg concentrations over time from 1887 to 1996. In the same individuals, δ15N, δ13C, and δ34S declined over time in gull feathers. In comparison, egg THg concentrations declined from 1970 to 2019 in two species of cormorants, likely reflecting decreases in local Hg sources. We conclude that diet shifts through time may have countered increased Hg deposition from long-range transport in glaucous-winged gulls. The lack of Hg trends over time in glaucous-winged gull feathers provides additional support that these gulls have decreased the amount of marine forage fish in their diet.


Assuntos
Charadriiformes , Mercúrio , Compostos de Metilmercúrio , Animais , Dieta , Monitoramento Ambiental , Plumas/química , Feminino , Masculino , Mercúrio/análise
8.
PLoS One ; 17(8): e0272836, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35947613

RESUMO

Charadriiformes represent one of the largest orders of birds; members of this order are diverse in morphology, behavior and reproduction, making them an excellent model for studying evolution. It is accepted that the avian putative ancestral karyotype, with 2n = 80, remains conserved for about 100 million years. So far, only a few species of Charadriiformes have been studied using molecular cytogenetics. Here, we performed chromosome painting on metphase chromosomes of two species of Charadriidae, Charadrius collaris and Vanellus chilensis, with whole chromosome paint probes from Burhinus oedicnemus. Charadrius collaris has a diploid number of 76, with both sex chromosomes being submetacentric. In V. chilensi a diploid number of 78 was identified, and the Z chromosome is submetacentric. Chromosome painting suggests that chromosome conservation is a characteristic common to the family Charadriidae. The results allowed a comparative analysis between the three suborders of Charadriiformes and the order Gruiformes using chromosome rearrangements to understand phylogenetic relationships between species and karyotypic evolution. However, the comparative analysis between the Charadriiformes suborders so far has not revealed any shared rearrangements, indicating that each suborder follows an independent evolutionary path, as previously proposed. Likewise, although the orders Charadriiformes and Gruiformes are placed on sister branches, they do not share any signature chromosomal rearrangements.


Assuntos
Anfípodes , Charadriiformes , Anfípodes/genética , Animais , Aves/genética , Charadriiformes/genética , Coloração Cromossômica/métodos , Evolução Molecular , Filogenia , Cromossomos Sexuais/genética
9.
mSphere ; 7(4): e0023822, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-35862807

RESUMO

Escherichia coli sequence type 963 (ST963) is a neglected lineage closely related to ST38, a globally widespread extraintestinal pathogenic ST causing urinary tract infections (UTI) as well as sepsis in humans. Our current study aimed to improve the knowledge of this understudied ST by carrying out a comprehensive comparative analysis of whole-genome sequencing data consisting of 31 isolates from silver gulls in Australia along with another 80 genomes from public resources originating from geographically scattered regions. ST963 was notable for carriage of cephalosporinase gene blaCMY-2, which was identified in 99 isolates and was generally chromosomally encoded. ST963 isolates showed otherwise low carriage of antibiotic resistance genes, in contrast with the closely related E. coli ST38. We found considerable phylogenetic variability among international ST963 isolates (up to 11,273 single nucleotide polymorphisms [SNPs]), forming three separate clades. A major clade that often differed by 20 SNPs or less consisted of Australian isolates of both human and animal origin, providing evidence of zoonotic or zooanthropogenic transmission. There was a high prevalence of virulence F29:A-:B10 pUTI89-like plasmids within E. coli ST963 (n = 88), carried especially by less variable isolates exhibiting ≤1,154 SNPs. We characterized a novel 115,443-bp pUTI89-like plasmid, pCE2050_A, that carried a traS:IS5 insertion absent from pUTI89. Since IS5 was also present in a transposition unit bearing blaCMY-2 on chromosomes of ST963 strains, IS5 insertion into pUTI89 may enable mobilization of the blaCMY-2 gene from the chromosome/transposition unit to pUTI89 via homologous recombination. IMPORTANCE We have provided the first comprehensive genomic study of E. coli ST963 by analyzing various genomic and phenotypic data sets of isolates from Australian silver gulls and comparison with genomes from geographically dispersed regions of human and animal origin. Our study suggests the emergence of a specific blaCMY-2-carrying E. coli ST963 clone in Australia that is widely spread across the continent by humans and birds. Genomic analysis has revealed that ST963 is a globally dispersed lineage with a remarkable set of virulence genes and virulence plasmids described in uropathogenic E. coli. While ST963 separated into three clusters, a unique specific clade of Australian ST963 isolates harboring a chromosomal copy of AmpC ß-lactamase encoding the gene blaCMY-2 and originating from both humans and wild birds was identified. This phylogenetically close cluster comprised isolates of both animal and human origin, thus providing evidence of interspecies zoonotic transmission. The analysis of the genetic environment of the AmpC ß-lactamase-encoding gene highlighted ongoing evolutionary events that shape the carriage of this gene in ST963.


Assuntos
Charadriiformes , Infecções por Escherichia coli , Escherichia coli , Animais , Austrália , Charadriiformes/microbiologia , Escherichia coli/genética , Infecções por Escherichia coli/transmissão , Infecções por Escherichia coli/veterinária , Humanos , Filogenia
10.
Curr Biol ; 32(17): 3800-3807.e3, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-35870447

RESUMO

Density-dependent prey depletion around breeding colonies has long been considered an important factor controlling the population dynamics of colonial animals.1-4 Ashmole proposed that as seabird colony size increases, intraspecific competition leads to declines in reproductive success, as breeding adults must spend more time and energy to find prey farther from the colony.1 Seabird colony size often varies over several orders of magnitude within the same species and can include millions of individuals per colony.5,6 As such, colony size likely plays an important role in determining the individual behavior of its members and how the colony interacts with the surrounding environment.6 Using tracking data from murres (Uria spp.), the world's most densely breeding seabirds, we show that the distribution of foraging-trip distances scales to colony size0.33 during the chick-rearing stage, consistent with Ashmole's halo theory.1,2 This pattern occurred across colonies varying in size over three orders of magnitude and distributed throughout the North Atlantic region. The strong relationship between colony size and foraging range means that the foraging areas of some colonial species can be estimated from colony sizes, which is more practical to measure over a large geographic scale. Two-thirds of the North Atlantic murre population breed at the 16 largest colonies; by extrapolating the predicted foraging ranges to sites without tracking data, we show that only two of these large colonies have significant coverage as marine protected areas. Our results are an important example of how theoretical models, in this case, Ashmole's version of central-place-foraging theory, can be applied to inform conservation and management in colonial breeding species.


Assuntos
Charadriiformes , Animais , Ecossistema , Dinâmica Populacional , Reprodução
11.
Sci Rep ; 12(1): 12981, 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35902737

RESUMO

Studies on time allocation of various activities are crucial to understand which behavioural strategy is the most profitable in a given context, and so why animals behave in a particular way. Such investigations usually focus on a time window when the studied activity is performed, often neglecting how the time devoted to focal activity affects time allocation to following-up behaviours, while that may have its own fitness consequences. In this study, we examined time allocation into three post-foraging activities (entering the nest with food, nest attendance, and colony attendance) in a small seabird species, the little auk (Alle alle). Since little auks alternate foraging trips of different duration (short and long) and purpose (offspring feeding and primarily self-feeding, respectively) we expected that duration of the following up in-colony activities would also vary, being longer after a long absence in the colony (because of greater need of reassessment of the current predation pressure and social interactions in the colony, and re-establishing the bond with the offspring and/or partner and/or neighbours after longer absence). We found that it was not always the case, as time allocation of the post-foraging in-colony activities was primarily year- and sex-specific. It highlights the need to consider year and sex effects in studies of behavioural ecology, as not doing so may lead to spurious conclusions. Interestingly, and despite a great inter-individual variation in time allocation in the post-foraging in-colony activities, little auk individuals were quite repeatable in their behavioural performance, which suggests these activities may reflect birds behavioural profile. Overall, post-foraging in-colony activity of the little auk, although not much dependent on duration/type of the preceding foraging flights, varies with respect to year and sex, and as such may be a proxy of behavioural plasticity of the population.


Assuntos
Charadriiformes , Comportamento Alimentar , Animais , Aves , Ecologia , Feminino , Masculino , Comportamento Predatório
12.
Sci Total Environ ; 843: 157058, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35780887

RESUMO

As a newly established World Natural Heritage site, the conservation of rare waterbird habitats in the Yancheng coastal wetlands has attracted wide international attention. In view of the importance of this area in international biodiversity conservation and waterbird habitat conservation, the study of the current situation of rare waterbird habitat networks with spatial isolation features of great demonstration significance to improve the habitat conservation quality of the heritage site. Based on the data obtained from habitat suitability assessments of rare waterbirds, this paper used complex network theory, ecological stepping-stone theory and circuit models to analyze the current status and robustness of rare waterbird habitat networks in the Yancheng coastal wetlands. The results showed that the stepping stones of the red-crowned cranes and the Oriental storks were mainly distributed around important habitat areas, including aquaculture ponds and reed marshes, with areas of 1275.68 hm2 and 1247.74 hm2, respectively, while the stepping stones of Saunders's gulls were mainly distributed within the Tiaozini habitat site, with an area of 1180.76 hm2. The stability and connectivity of the habitat networks of red-crowned cranes and Oriental storks in the northern habitat area were better. At the Tiaozini habitat site, there was spatial isolation and low connectivity among the habitats and stepping stones of Saunders's gulls. In the optimal protection scenario, the stability and connectivity of the habitat network structure of red-crowned cranes and Oriental storks were the best, and the networks tended to exhibit assortativity. In the random destruction scenario, the connectivity of the habitat networks of Saunders's gulls was the lowest, and the network structure was the most fragile. Finally, the optimization and restoration patterns of habitat network based on improving the support capacity of important habitat nodes and the enhancement of the stability and connectivity of the stepping-stone networks were proposed.


Assuntos
Charadriiformes , Ecossistema , Animais , Biodiversidade , Aves , Conservação dos Recursos Naturais , UNESCO , Áreas Alagadas
13.
Ecotoxicol Environ Saf ; 242: 113868, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35863215

RESUMO

Environmental pollution has emerged as a major threat to bird populations. Many shorebird populations are declining, although contamination has been documented in some shorebirds, evidence of negative impacts is sparse and this important topic remains understudied. To guide future research and develop effective conservation strategies, we carried out a comprehensive review of environmental pollutants and their consequences on shorebirds. In total, we found 93 relevant articles which examined pollutant contamination in ~37% (79 of 215) of all shorebird species, mostly from the Charadriidae and Scolopacidae families. Studies were geographically biased: the majority were conducted in American flyways, while only 1 was found from Australasia and few were conducted in Asian flyways. The main geographic gap for research includes East Africa, South Asia and Siberian Arctic. The most well-documented pollutants included mercury (Hg, 37 studies), cadmium (33), and lead (Pb, 28); less well studied pollutants were barium (1), calcium (1), strontium (1), dicofols (1), and other newly emerging contaminants, such as plastic debris/microplastics (4) and antibiotics resistance (2). Several pollutants have caused considerable concerns in shorebirds, including embryotoxicity caused by PCBs at non-optimum temperature (laboratory experiments); reduced reproduction performance linked to maternal Hg and paternal Pb (field evidence); and reduced refueling and flight performance related to oil contamination (both field and laboratory evidence). Our results confirm that an in-depth understanding of the local, regional and global factors that influence population trends of shorebirds in light of increasing pollution threats is essential for accurate and effective management and conservation strategies.


Assuntos
Charadriiformes , Poluentes Ambientais , Mercúrio , Animais , Aves , Monitoramento Ambiental , Poluentes Ambientais/análise , Poluentes Ambientais/toxicidade , Humanos , Chumbo , Plásticos
14.
Artigo em Inglês | MEDLINE | ID: mdl-35805592

RESUMO

Beach sand may act as a reservoir for numerous microorganisms, including enteric pathogens. Several of these pathogens originate in human or animal feces, which may pose a public health risk. In August 2019, high levels of fecal indicator bacteria (FIB) were detected in the sand of the Azorean beach Prainha, Terceira Island, Portugal. Remediation measures were promptly implemented, including sand removal and the spraying of chlorine to restore the sand quality. To determine the source of the fecal contamination, during the first campaign, supratidal sand samples were collected from several sites along the beach, followed by microbial source tracking (MST) analyses of Bacteroides marker genes for five animal species, including humans. Some of the sampling sites revealed the presence of marker genes from dogs, seagulls, and ruminants. Making use of the information on biological sources originating partially from dogs, the municipality enforced restrictive measures for dog-walking at the beach. Subsequent sampling campaigns detected low FIB contamination due to the mitigation and remediation measures that were undertaken. This is the first case study where the MST approach was used to determine the contamination sources in the supratidal sand of a coastal beach. Our results show that MST can be an essential tool to determine sources of fecal contamination in the sand. This study shows the importance of holistic management of beaches that should go beyond water quality monitoring for FIB, putting forth evidence for beach sand monitoring.


Assuntos
Bactérias/isolamento & purificação , Praias/normas , Areia/microbiologia , Poluição da Água , Animais , Bactérias/classificação , Bactérias/genética , Bacteroides/genética , Bacteroides/isolamento & purificação , Charadriiformes , Cães , Monitoramento Ambiental/métodos , Fezes/microbiologia , Portugal , Ruminantes , Microbiologia da Água , Poluição da Água/análise
15.
Sci Total Environ ; 845: 157244, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35817107

RESUMO

This study monitored the spatiotemporal trends of persistent organic pollutants (POPs) contamination along the Korean coasts using eggs of the black-tailed gull, a resident bird that occupies a high trophic position in the marine food web. Black-tailed gull eggs were collected from three breeding islands located in the western (Seoman-do), southern (Hong-do), and eastern (Dok-do) seas of Korea during 2015-2019, and egg contents were analyzed for classical and emerging POPs. Among the target analytes, levels of emerging POPs such as brominated flame retardants (BFRs) and perfluoroalkyl acids (PFAAs) were significantly higher in eggs from Seoman-do than other islands. Global positioning system tracking data show that seagulls from Seoman-do traveled frequently to two neighboring major cities (Incheon and Seoul), indicating that the accumulation of BFRs and PFAAs in bird eggs is directly affected by the pollution characteristics of urban areas. Overall, the ratios of PFAA and BFR to the total POPs in eggs from the islands increased over time, while the proportion of classical POPs decreased. A shift from classical POPs to BFRs and PFAAs in seagull eggs was identified. Interestingly, perfluorooctanoic acid (PFOA), which exhibits limited bioaccumulation, was detected at higher levels in eggs from Seoman-do, indicating widespread use of PFOA and maternal transfer to seabird eggs. Continuous monitoring of PFAAs in marine environments of Korea is needed. This study demonstrates that monitoring of seabird eggs is effective for detecting spatial and temporal trends of POPs in the marine environment, and provides insights into emerging POPs such as PFAAs.


Assuntos
Charadriiformes , Poluentes Ambientais , Retardadores de Chama , Animais , Aves , Ovos/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Poluentes Orgânicos Persistentes
16.
PLoS One ; 17(7): e0270224, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35776754

RESUMO

Understanding factors that influence a species' distribution and abundance across the annual cycle is required for range-wide conservation. Thousands of imperiled red knots (Calidris cantus rufa) stop on Virginia's barrier islands each year to replenish fat during spring migration. We investigated the variation in red knot presence and flock size, the effects of prey on this variation, and factors influencing prey abundance on Virginia's barrier islands. We counted red knots and collected potential prey samples at randomly selected sites from 2007-2018 during a two-week period during early and peak migration. Core samples contained crustaceans (Orders Amphipoda and Calanoida), blue mussels (Mytilus edulis), coquina clams (Donax variabilis), and miscellaneous prey (horseshoe crab eggs (Limulus polyphemus), angel wing clams (Cyrtopleura costata), and other organisms (e.g., insect larvae, snails, worms)). Estimated red knot peak counts in Virginia during 21-27 May were highest in 2012 (11,959) and lowest in 2014 (2,857; 12-year peak migration [Formula: see text] = 7,175, SD = 2,869). Red knot and prey numbers varied across sampling periods and substrates (i.e., peat and sand). Red knots generally used sites with more prey. Miscellaneous prey ([Formula: see text] = 2401.00/m2, SE = 169.16) influenced red knot presence at a site early in migration, when we only sampled on peat banks. Coquina clams ([Formula: see text] = 1383.54/m2, SE = 125.32) and blue mussels ([Formula: see text] = 777.91/m2, SE = 259.31) affected red knot presence at a site during peak migration, when we sampled both substrates. Few relationships between prey and red knot flock size existed, suggesting that other unmeasured factors determined red knot numbers at occupied sites. Tide and mean daily water temperature affected prey abundance. Maximizing the diversity, availability, and abundance of prey for red knots on barrier islands requires management that encourages the presence of both sand and peat bank intertidal habitats.


Assuntos
Bivalves , Charadriiformes , Animais , Ecossistema , Areia , Estações do Ano , Virginia
17.
Proc Biol Sci ; 289(1978): 20220139, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35858061

RESUMO

Determinants of individual variation in reallocation of limited resources towards self-maintenance versus reproduction are not well known. We tested the hypothesis that individual heterogeneity in long-term 'somatic state' (i) explains variation in endocrine and behavioural responses to environmental challenges, and (ii) is associated with variation in strategies for allocating to self-maintenance versus reproduction. We used relative telomere length as an indicator of somatic state and experimentally generated an abrupt short-term reduction of food availability (withdrawal of food supplementation) for free-living seabirds (black-legged kittiwakes, Rissa tridactyla). Incubating male kittiwakes responded to withdrawal by increasing circulating corticosterone and losing more weight compared to continuously supplemented controls. Males with longer telomeres increased time in directed travel regardless of treatment, while experiencing smaller increases in corticosterone. Males with longer telomeres fledged more chicks in the control group and tended to be more likely to return regardless of treatment. This study supports the hypothesis that somatic state can explain variation in short-term physiological and behavioural responses to challenges, and longer-term consequences for fitness. Male kittiwakes with longer telomeres appear to have prioritized investment in self over investment in offspring under challenging conditions.


Assuntos
Charadriiformes , Corticosterona , Animais , Charadriiformes/fisiologia , Alimentos , Masculino , Reprodução/fisiologia , Telômero
18.
Ecohealth ; 19(2): 203-215, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35655049

RESUMO

Extreme weather events, particularly heavy rainfall, are occurring at greater frequency with climate change. Although adverse human health effects from heavy rainfall are often publicized, impacts to free-ranging wildlife populations are less well known. We first summarize documented associations of heavy rainfall on wildlife health. We then report a novel investigation of a salmonellosis outbreak in a colony of black skimmers (Rynchops niger) in Florida, USA. During June-September 2016, heavy rainfall resulted in the discharge of millions of gallons of untreated wastewater into the Tampa Bay system, contaminating the water body, where adult skimmers foraged. At least 48 fledglings died, comprising 39% of the colony's nesting season's offspring. Of eight examined deceased birds from the colony, six had a systemic salmonellosis infection. Isolates were identified as Salmonella enterica serotype Typhimurium. Their pulsed-field gel electrophoresis patterns were identical to each other and matched those from several human Salmonella sp. infections. Differences among whole-genome sequences were negligible. These findings and the outbreak's epidemic curve suggest propagated transmission occurred within the colony. A multidisciplinary and One Health approach is recommended to mitigate any adverse effects of climate change-driven stochastic events, especially when they place already imperiled wildlife at further risk.


Assuntos
Charadriiformes , Infecções por Salmonella , Animais , Aves , Níger/epidemiologia , Salmonella , Infecções por Salmonella/epidemiologia
19.
J Wildl Dis ; 58(3): 697-700, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35704500

RESUMO

Burhinus oedicnemus distinctus is an endemic subspecies of Eurasian Stone-curlew present in the Canary Islands. Their populations are rapidly declining, mainly because of anthropogenic impacts. This report describes valvular endocarditis and septicemia in a Eurasian Stone-Curlew with left foot loss and severe contralateral bumblefoot.


Assuntos
Bacteriemia , Charadriiformes , Endocardite , Infecções Estreptocócicas , Animais , Bacteriemia/veterinária , Endocardite/veterinária , Infecções Estreptocócicas/veterinária , Streptococcus
20.
J Anim Ecol ; 91(9): 1797-1812, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35675093

RESUMO

Timing of breeding, an important driver of fitness in many populations, is widely studied in the context of global change, yet despite considerable efforts to identify environmental drivers of seabird nesting phenology, for most populations we lack evidence of strong drivers. Here we adopt an alternative approach, examining the degree to which different populations positively covary in their annual phenology to infer whether phenological responses to environmental drivers are likely to be (a) shared across species at a range of spatial scales, (b) shared across populations of a species or (c) idiosyncratic to populations. We combined 51 long-term datasets on breeding phenology spanning 50 years from nine seabird species across 29 North Atlantic sites and examined the extent to which different populations share early versus late breeding seasons depending on a hierarchy of spatial scales comprising breeding site, small-scale region, large-scale region and the whole North Atlantic. In about a third of cases, we found laying dates of populations of different species sharing the same breeding site or small-scale breeding region were positively correlated, which is consistent with the hypothesis that they share phenological responses to the same environmental conditions. In comparison, we found no evidence for positive phenological covariation among populations across species aggregated at larger spatial scales. In general, we found little evidence for positive phenological covariation between populations of a single species, and in many instances the inter-year variation specific to a population was substantial, consistent with each population responding idiosyncratically to local environmental conditions. Black-legged kittiwake Rissa tridactyla was the exception, with populations exhibiting positive covariation in laying dates that decayed with the distance between breeding sites, suggesting that populations may be responding to a similar driver. Our approach sheds light on the potential factors that may drive phenology in our study species, thus furthering our understanding of the scales at which different seabirds interact with interannual variation in their environment. We also identify additional systems and phenological questions to which our inferential approach could be applied.


Assuntos
Charadriiformes , Animais , Mudança Climática , Estações do Ano
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