Acridotheres Tristis Research Articles

Preliminary observations suggest Common Myna prefer lipid over protein and carbohydrate foods in a pairwise choice experiment

Common Mynas Sturnus tristis, previously known as Acridotheres tristis, are considered among the world’s worst most invasive species. However, relatively little is known about the factors that affect their persistence and spread in new environments. They have been observed feeding on a wide range of foods, including anthropogenic foods in urban areas. Their diet preferences are relatively unknown. Therefore, we investigated the macronutrient preferences of Common Mynas in captivity. Common Mynas (n = 10) were given a pairwise choice of three different diets (high lipid, high protein, and high carbohydrate diets) in the laboratory to determine their preference. Common Mynas showed a preference for the high lipid food, followed by high protein, with the high carbohydrate food least preferred. Consequently, this suggests Common Mynas preferred food high in lipids compared with proteins and carbohydrates, but additional study is needed to confirm this. Implications are Common Mynas should not be a problem for South African agricultural areas, because this industry generally provides relatively few dietary items high in fat, so we expect the Common Myna will continue to be distributed mainly in urban areas of South Africa where anthropogenic foods relatively high in fat are more common.

Concurrent multiple parasitic infection in four spontaneous cases of free ranging common myna (Acridotheres tristis)

Concurrent multiple parasitic infection in four spontaneous cases of free ranging common myna (Acridotheres tristis)

Isolation and Characterization of Novel Trichomonas gallinae Ribotypes Infecting Domestic and Wild Birds in Riyadh, Saudi Arabia

Trichomonas gallinae, a single-celled protozoan parasite, is a causative agent of the disease trichomonosis, which is distributed worldwide and has recently been highlighted as a pandemic threat to several wild bird species. The aim of this study was to determine the prevalence and genotypic diversity of T. gallinae in Riyadh, Saudi Arabia. For this purpose, 273 oral swab samples from different bird species (feral pigeon Columba livia, common mynah Acridotheres tristis, chicken Gallus gallus domesticus, turkey Meleagris gallopavo, and ducks Anatidae) were collected and tested for T. gallinae infection with InPouch™ TV culture kits. The results showed that the overall prevalence of T. gallinae in these samples was 26.4% (n = 72). The PCRs were used to detect the internal transcribed spacer (ITS) region of T. gallinae, and the results of the sequence analysis indicated genetic variation. Among 48 sequences, we found 15 different ribotypes, of which 12 were novel. Three had been previously described as ribotypes A, C, and II. To our knowledge, this study demonstrated the presence of T. gallinae strain diversity in Saudi Arabian birds for the first time and revealed that ribotypes A and C are predominant among Riyadh birds.

When the winners are the losers: Invasive alien bird species outcompete the native winners in the biotic homogenization process

Species are declining worldwide, but while some are becoming threatened, few others thrive under novel environmental conditions. Land use changes and biological invasion are the main drivers of this ‘biotic homogenization’ (BH) that increasingly occurs in human-dominated landscapes. Among birds, several groups of species have been identified as ‘winners’ in this process (e.g. invasive and native urban specialists and generalist species). Yet, as populations continue to grow, competition can appear between those groups and it is not yet clear who are the primary ‘winners’ in the BH process. Here, we analyze trends of common native and non-native birds during the last 15 years across Israel, where large populations of very destructive invasive alien bird species were introduced towards the end of the previous century, using a nation-wide citizen-science program, and two local standardized surveys. Community and population analyses showed that the non-native species are the primary ‘winners’ of the BH process. Native urban specialists and generalist species that were previously considered as ‘winners’ are now among the ‘losers’. For instance, populations of the invasive common myna increased dramatically, while populations of the previously widespread house sparrow strongly decreased. Previous studies conducted in Israel have shed light on the mechanisms through which invasive bird species can impact native species, notably competition. We show that these processes are among the key factors that drive population declines and changes in bird communities. This highlights the importance of acting now, especially since non-native species are currently spreading from human-dominated areas to more natural environments.

The effect of local species composition on the distribution of an avian invader

Estimating the potential distribution of invasive species has been primarily achieved by employing species distribution models (SDM). Recently introduced joint species distribution models (JSDM) that include species interactions are expected to improve model output. Here we compare the predictive ability of SDM and JSDM by modelling the distribution of one of the most prolific avian invaders in the world, the common myna (Acridotheres tristis), in a recent introduction in Israel. Our results indicate that including information on the local species composition did not improve model accuracy, possibly because of the unique characteristics of this species that include broad environmental tolerance and behavior flexibility. However, the JSDM provided insights into co-occurrence patterns of common mynas and their local heterospecifics, suggesting that at this time point, there is no evidence of species exclusion by common mynas. Our findings suggest that the invasion potential of common mynas depends greatly on urbanization and less so on the local species composition and reflect the major role of anthropogenic impact in increasing the distribution of avian invaders.

Parasitological and molecular survey of scattered parasitism by trichomonads in some avian species in Iran

ABSTRACT Outbreaks of avian trichomonosis are being reported worldwide; meanwhile, the genetic and virulence variations are under investigation. In this study, the occurrence and genetic variability of oral or faecal trichomonads among various avian species were investigated. Samples obtained from either the oropharyngeal cavity, crop/oesophagus, droppings/cloaca, or conjunctival swabs of avian species were inspected for flagellates. Phylogenetic analysis of partial ITS1-5.8s rRNA-ITS2 sequences from selected samples was performed to investigate the genetic diversity of the isolates. Investigation of 737 birds revealed an infection rate of 15.7% in the upper gastrointestinal tract, 7.3% in the faecal samples, and 0.7% involvement of the conjunctiva. Phylogenetic analysis of partial ITS1-5.8s rRNA-ITS2 sequences from selected samples, identified genotypes A and B of Trichomonas gallinae and genogroups A-C and E of Tetratrichomonas gallinarum. A novel ITS genotype of intestinal trichomonads was also detected in hooded crow (Corvus cornix) and common mynah (Acridotheres tristis). In the present study, in addition to Columbiformes and Falconiformes, trichomonads were detected in Passeriformes and Galliformes with the involvement of organs other than the gastrointestinal tract. Genotype A T. gallinae was detected in domestic pigeons (Columba livia domestica), a laughing dove (Spilopelia senegalensis), a common kestrel (Falco tinnunculus), a budgerigar (Melopsittacus undulates), and a canary (Serinus canaria). Distinct genotype B was detected in a common mynah and a budgerigar. Genogroups A-C of T. gallinarum were also demonstrated in Galliformes and Anseriformes. Furthermore, two novel trichomonad ITS genotypes were detected in hooded crows and a common mynah warranting detailed multi-locus molecular analysis. RESEARCH HIGHLIGHTS ITS diversity of trichomonads was shown in various avian species. Diversity of the parasites’ target organ and clinical manifestations was demonstrated. Two novel ITS genotype trichomonads from common mynah and hooded crow were identified.

Removing of Ventricular Foreign Body in a Common Mynah (Acridotheres tristis) by Celiotomy Technique: Case Report

Case description- A 2 years old common mynah (Acridotheres tristis) of unknown sex, weighing 180 g, with history of lack of appetite and depression was referred to the veterinary hospital of Lorestan University. Clinical findings- Clinical signs included: anorexia, depression and diarrhea. Lateral radiograph showed a soft tissue opacity foreign body within the body with its distal end, seemingly in the ventriculus and its proximal end extending to the thoracic esophagus. Treatment and outcome- Because the foreign body can cause obstruction, the decision was made to remove the foreign body by surgery technique. The feathers at the incision site were plucked and the skin was prepared in the usual surgical procedure. An incision (2cm) was made along the ventral midline and after tenting the abdominal musculature and O2 was distributed in the abdominal cavity. Then ventriculus was approached through an initial stab incision in the mid-portion of the ventricular and the foreign body, which was a sewing elastic band, was pulled out slowly with a small mosquito hemostat. Clinical relevance- For removing of a foreign body in GI tract of birds several techniques were reported that depended on size, composition and position of FB in GI tract. In this mynah, due to the position of FB in ventricular cavity, celiotomy method was used. In abdominal surgery changes in the mechanical properties of the respiratory system, may reduce the volume of breathing. So, for preventing of hypoxia, using of O2 is useful.

An Investigation into the Accumulation of Air Borne Trace Metals in the Lungs of Common Myna Acridotheres tristis and Bank Myna Acridotheres ginginianus Captured from Urban and Semi Urban Areas of Lahore and Pattoki, Pakistan.

With increasing urbanization and industrialization, clean air is becoming a scarce resource. During the present investigation, concentrations of metals (Pb, Ni and Zn) in the atmosphere and their subsequent deposition in the lungs of two common avian species, common myna, Acridotheres tristis (n = 30) and bank myna, A. ginginianus (n = 20), captured from urban areas of Lahore city and semi-urban areas of Pattoki city 80km away from main city of Lahore were determined. The obtained results were analyzed statistically using Independent sample t test and Pearson's correlation. A comparison of trace metal concentrations in air of both the cities was also carried out. Statistically, significant variations were recorded for Pb (t (7) = - 4.276, p = 0.001) while non-significant differences were observed for both Ni (t (7) = 0.049, p = 0.962) and Zn (t (7) = 1.555, p = 0.146).

Diversity and temporal variation of the bird community in paddy fields of Kadhiramangalam, Tamil Nadu, India

Paddy, a major food crop of India, provides a variety of habitats in a short period of time and supports diverse organisms. Paddy fields also harbour many birds with varying species composition across the different cultivation phases of paddy. This study, conducted in the paddy fields of Kadhiramangalam, Tamil Nadu, India, recorded the bird community composition there during the various cultivation phases of paddy. The bird community data was analysed and a total of 87 bird species were recorded from the study area belonging to 41 families and 13 orders. The growth phase (PS 3) is the most diverse phase. The bird composition showed a significant variation across the paddy cultivation phases with overall average dissimilarity of 71.41%. The patterns shown by graphs of bird species composition across the paddy cultivation phases is based on guild, habitat usage and order overlap and elucidates that the change in bird community composition temporally can be attributed to the niche variability across the paddy cultivation phases. The major species contributing to these changes observed are Black-headed Munia, Baya Weaver, Common Sandpiper, Barn Swallow, Common Myna, and Black Drongo in this region. 

Assessment of Avifaunal Diversity in Riverine and Urban Areas of Layyah along the River Indus, Punjab-Pakistan

Layyah City is located along the River Indus and provides rich habitat for a wide range of resident and migratory bird species. The present study documents for the first time the avifaunal diversity and abundance of urban and riverine sites of Layyah. Potential habitats around the city were identified and three study sites were selected, one in each of the main habitat types. A total of 223 species was recorded: 92 residents, 87 winter visitors, 42 passage migrants and two new records from the area. A Shannon Wiener Index of 4.36 indicates that the area has a high level of biodiversity. Of the species recorded, 16 are included in the IUCN Red list as vulnerable (N=6), near threatened (N=9) or endangered (N=1). The most abundant species were House Crow Corvus splendens, House Sparrow Passer domesticus, Common Myna Acridotheres tristis and Common Starling Sturnus vulgaris. Two species, Houbara or McQueen's Bustard Chlamydotis macqueenii and Black-headed Ibis Threskiornis melanocephalus were recorded for the first time from the area. Potential threats to the avian diversity of the area are hunting, habitat loss, and pollution.

Features of the Common Myna in Green Areas of Almaty

Features of the Common Myna in Green Areas of Almaty

Characterization of the complete mitochondrial genome of Sphaerirostris picae (Rudolphi, 1819) (Acanthocephala: Centrorhynchidae), representative of the genus Sphaerirostris.

The Centrorhynchidae (Acanthocephala: Palaeacanthocephala) is a cosmopolitan family commonly found in various avian and mammalian hosts. Within Centrorhynchidae, species of the genus Sphaerirostris Golvan, 1956 are usually parasitic in the digestive tract of various passerine birds. In the present study, adult specimens of Sphaerirostris picae (Rudolphi, 1819), the type species of this genus, were recovered from the small intestine of Acridotheres tristis (Sturnidae) and Dendrocitta vagabunda (Corvidae) in Pakistan. Molecular data from the nuclear or mitochondrial genome is either very limited or completely absent from this phylogenetically understudied group of acanthocephalans. To fill this knowledge gap, we sequenced and determined the internal transcribed spacers of ribosomal DNA (ITS rDNA) and the complete mitochondrial (mt) genome of S. picae. The ITS rDNA of S. picae was 95.2% similar to that of Sphaerirostris lanceoides which is the only member of the Centrorhynchidae whose ITS rDNA is available in GenBank. The phylogenetic tree based on the amino acid sequences of 12 mt protein-coding genes (PCGs) placed S. picae close to Centrorhynchus aluconis in a monophyletic clade of Polymorphida which also contain members of the families Polymorphidae and Plagiorhynchidae on separate branches. The mt gene arrangement, nucleotide composition and codon usage of 12 PCGs were discussed and compared with those of other acanthocephalan mt genomes. Within the Centrorhynchidae, S. picae and C. aluconis showed 67.7-86.8% similarity in the nucleotide sequences of 12 PCGs and 2 rRNAs, where nad4L is the most conserved gene while atp6 is the least conserved. The similarity in amino acid sequences ranged from 68.1 to 91.8%, where cox1 was recorded as the most conserved gene, while atp6 is highly variable among 12 PCGs. This novel mt genome of S. picae provides genetic resources for further studies of phylogenetics and molecular epidemiology of acanthocephalans.

It’s a trap! Invasive common mynas learn socially about control-related cues

Social learning of novel threats coupled with adaptive generalization from learned to novel cues together provide the cognitive mechanisms by which adaptive avoidance of threats can spread rapidly both within and across generations. Whereas attention to effects of fishing and hunting on prey is increasing, nothing is known about how human predation can alter the behavior of invasive animals. Here, we examined whether common (Indian) mynas, Acridotheres tristis, one of the most widespread invasive birds in Australia and invasive to many other parts of the world, are learning to respond to anthropogenic predation. We analyzed behavior at an experimental food patch provisioned by 2 distinctly clothed persons both before and after mynas had observed one of the 2 persons seemingly capture conspecifics inside a trap placed at the food patch. After the demonstration, mynas landed in smaller numbers at the food patch and took longer to land. Further, mynas alarm called more when provisioned by the person who had been involved in trapping. Future work will determine whether narrow generalization gradients are a consistent feature of synanthropic species or whether they broaden as a function of human predation threat level as is predicted by the Predator Recognition Continuum Hypothesis. Practical implications for control are discussed. Can common mynas, one of the World's most invasive birds and target of much control effort, learn to avoid trapping? After watching mynas being captured by a person who had previously fed them, observer mynas alarm called specifically to that person. They also learned the place where trapping occurred and showed generalized changes in risk-awareness. Mynas show a remarkable capacity to learn socially, which explains why they are becoming more risk-averse in areas where they are trapped.

Plasma Biochemical and Lipid Panel Reference Intervals in Common Mynahs (Acridotheres tristis).

Mynahs are popular pet and aviary birds. Captive mynahs are prone to metabolic disorders, such as obesity, hepatic lipidosis, and atherosclerosis, and determination of a plasma biochemical reference interval is essential for diagnosis, treatment, and monitoring of these disorders. To establish reference intervals for the lipoprotein panel and plasma activity of liver enzymes in common mynahs (Acridotheres tristis), glucose, cholesterol, triglycerides, high and low density lipoprotein concentrations, and activities of aspartate aminotransferase, alkaline phosphatase, gamma-glutamyl transferase, and lactate dehydrogenase were measured in 56 adult healthy individuals. The data were grouped according to sex and body weight. For all variables, no significant differences were found between male and female mynahs, and body weight had no effect on lipoprotein fractions. Our results provide a reliable reference interval for some blood biochemical values in healthy common mynahs that could be useful for diagnosing and monitoring disease problems.

Avian frugivory and seed dispersal of an exotic palm Ptychosperma macarthurii (H. Wendl. ex H. J. Veitch) H. Wendl. ex Hook. f.

Frugivory and seed dispersal of Ptychosperma macarthurii were studied at Palmetum of KFRI Peechi campus. The whole day was divided into four time intervals morning (07.00–10.00), midday (10.00–01.00), afternoon (01.00–04.00), evening (04.00–07.00) for data collection. It was recorded that 13 bird species belonging to 11 families have been found to feed the ripened fruits of this exotic palm. The frugivores are Ocyceros griseus, Psilopogon viridis, Dendrocitta vagabunda, Eudynamys scolopaceus, Copsychus saularis, Spilopelia chinensis, Oriolus xanthomonas, Turdus simillimus, Myophonus horsfieldii, Pycnonotus cafer, Acridotheres javanicus, Acridotheres tristis and Pycnonotus jacosus. In the present study, birds preferred maximum feeding visit during morning and midday hours and minimum during evening and afternoon hours. Among 13 avian frugivores observed, Myna (2 species) and Rufous treepie made their fruit feeding visits in group and with other species and remaining species visited as single as well as with other species. It had been observed that, among avian frugivores, D. vagabunda consumed maximum number of fruits (average 6, n = 2) to be followed by A. javanicus (average 5, n = 2) O. griseus (average 9, n = 4) and appeared to be the major dispersers of P. macarthurii seeds.

Global invasion in progress: modeling the past, current and potential global distribution of the common myna

Determining the distribution and potential ranges of detrimental invasive species has become an essential task in light of their impacts on the environment. However, this effort has been challenging, especially for global invaders. Our goal was to test whether potential ranges of global invaders can be predicted, and examine the factors that shape them by studying the past, current and potential global distribution of a broad-ranging avian invader. We used the common myna (Acridotheres tristis), one of the most broad-ranging avian invaders whose range is currently expanding globally, as a case study. We collected the first detailed global database of global occurrence (n = 7990) of the common myna over the past 150 years, including records from the native and the introduced ranges. We employed MaxEnt to construct species distribution models (SDM) for the global database using climatic, anthropogenic and environmental factors. We provide evidence that invasive species distributions can be predicted from older records, and that model accuracy requires integrating data from the introduced range. This first comprehensive distribution for an avian invader indicates an extensive expansion in the common myna global distribution, with the potential of large areas worldwide being at risk of common myna invasion, thus threatening local biodiversity globally. Range expansion has been facilitated by proximity to urbanized areas and broad environmental tolerance. Our findings reflect the major role of anthropogenic impact in increasing the global distribution of avian invaders and emphasize the value of using SDMs to inform global management practices.

State of Wyoming v. U.S. Dep’t of the Interior Confused Agency Overlap with Preclusion: BLM Had Authority to Promulgate the Fracking Rule for Public Lands, Not Tribal Lands

State of Wyoming v. U.S. Dep’t of the Interior Confused Agency Overlap with Preclusion: BLM Had Authority to Promulgate the Fracking Rule for Public Lands, Not Tribal Lands

Reduced song complexity in founder populations of a widely distributed songbird

Reduced vocal diversity in founder populations of songbirds is particularly well described in congeners and conspecifics introduced to remote islands but has rarely been examined in species that have been introduced to both island and mainland systems across an expansive geographical range. We examined male between‐ and within‐song complexity variations between founder and native populations of the widely distributed Common Myna Acridotheres tristis and predicted reduced complexity within individuals from founder populations. The percentage of unique songs within a repertoire and within‐song complexity were significantly lower in Mynas from founder populations. This reduced song complexity suggests that vocal founder effects may be exhibited in both island and mainland founder populations.

Two speed invasion: assisted and intrinsic dispersal of common mynas over 150 years of colonization

AbstractAimDespite the common myna's widespread distribution, and the significant impact it has caused in parts of its non‐native range, there have been no comprehensive genomic studies of its invasion of any region. We aimed to characterize the common myna invasion of the Australian continent to understand its population genetic landscape, introduction history, dispersal characteristics, and the interconnectedness between different source populations and invasive fronts.LocationCommon mynas from 26 geographical locations spanning the Australian continent were utilized in this study.TaxonCommon myna (Acridotheres tristis).MethodsWe used a reduced genome representation method (DArTseq) to generate thousands of single nucleotide polymorphism markers in 462 common mynas. We then applied population genomic techniques to identify the common myna's population attributes such as gene flow, genetic diversity, and effective dispersal, all of which are critical for understanding geographical range expansion of pest species.ResultsWe found significant genetic structuring across the common myna's Australian distribution, indicating limited levels of effective dispersal amongst the populations founded from historic introductions in the 19th century. The historic introduction points were found to be genetically distinct, such that in the region on the invasion front where admixture did occur, myna populations exhibited higher genetic diversity than in the source populations. Significant isolation by distance was evident amongst populations derived from the same founding population, with genetic diversity decreasing moving away from the point of colonization, and in general, higher levels of gene flow from source to front than vice versa.Main conclusionsThis study indicates that despite a 150‐year colonization history of mynas in Australia, contemporary genetic structure still largely reflects human‐mediated dispersal. However, expanding populations are now connecting and the consequent increased genetic diversity may improve evolutionary potential. These results suggest that more management focus should be directed towards the invasion fronts, rather than the large, historic source populations.

Sugar preference of invasive Common Mynas (Sturnus tristis)

Nectarivorous and frugivorous birds have been found to select their diet according to sugar type and concentration. Consequently, many studies of sugar preference have been conducted on various avian species. Common Mynas, Sturnus tristis, previously known as Acridotheres tristis, are considered amongst the 100 worst invasive species worldwide and damage fruit crops in some countries. However, their sugar preferences have never been studied. Therefore, we investigated the effect of sugar type and concentration on sugar preference and assimilation efficiency in Common Mynas (n = 7). Birds were given pairwise choice tests of sugars (fructose, sucrose and glucose) of 5 g/ml (5%) to test sugar preference. Common Mynas showed preference for glucose over fructose and sucrose. To determine at which concentrations they prefer glucose, they were offered three different concentrations of glucose (5, 10 and 25%). They showed distinct preference for the 10% concentration of glucose in comparison with 5% and 25% glucose nectars. The birds maintained body mass in the respective experimental trials thus showed sufficient energy intake. Common Mynas failed to digest and absorb sucrose, but fructose and glucose were digested and assimilated efficiently for all concentrations. Results of this study showed that Common Mynas prefer glucose, especially at ~ 10% concentration. Species distribution is determined by food resources, and these results on sugar type and preference of Common Mynas might contribute to preventing or managing their spread in South Africa.