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The behaviour and diet of the Tasman parakeet (Cyanoramphus cookii) have not been quantitively described. We quantified the relative frequency of behaviours and diversity of food items for the spec...

Blossom-headed Parakeet Psittacula roseate is listed as Near Threatened on the IUCN Red List of Threatened Species because of its habitat loss, and declining population. In this study, we first sequenced and described the complete mitochondrial genome and phylogeny of P. roseata. The whole genome of P. roseata was 16,814 bp in length, and contained 14 protein-coding genes, 22 transfer RNA genes, 2 ribosome RNA genes, and 1 non-coding control regions. The overall base composition of the mitochondrial DNA was 31.88% for A, 22.00% for T, 32.88% for C, 13.23% for G, with a GC content of 46.11%. A phylogenetic tree strongly supported that genus Psittacula closely related with genus Eclectus by highly probability.

The Rose-ringed Parakeet (Psittacula krameri) was recorded in Turkey for the first time in 1975 and has since then established breeding populations in at least six cities as a consequence of intentional and accidental introductions. Parakeet sightings have been recorded in and around urban areas and records are available from 26 provinces. It is most abundant in stanbul, followed by zmir, Ankara, Yalova, Antalya, and Sanlurfa. The distribution and population size has increased continuously especially since the mid-2000s. The population is estimated to be now over 1,355 individuals in the country, which is still moderate compared to some other West European countries.

In aviculture, lovebirds are considered one of the most popular birds to keep. This African parakeet is known for its range of plumage colors and ease to tame. Plumage variation is the most important price-determining trait of these birds, and also the main selection criterion for breeders. Currently, no genetic screening tests for traits of economic importance or to confirm pedigree data are available for any of the nine lovebird species. As a starting point to develop these tests, the de novo genome of Agapornis roseicollis (rosy-faced lovebird) was sequenced, assembled, and annotated. Sequencing was done on the Illumina HiSeq 2000 platform and the assembly was performed using SOAPdenovo v2.04. The genome was found to be 1.1 Gb in size and 16,044 genes were identified and annotated. This compared well with other previously sequenced avian genomes, such as the chicken, zebra finch, and budgerigar. To assess genome completeness, the number of benchmarking universal single-copy orthologs were identified in the genome. This was compared to other previously assembled avian genomes and the results indicated that the genome will be useful in the development of genetic screening tests to aid lovebird breeders in selecting breeding pairs.

Indian rose-ringed parakeet (Psittacula krameri) is one of the most recognizable illegally trafficked wild birds. With feral populations in Europe and Australia, its phylogeny and taxonomy ...

Cyanoramphus parakeets are a key biogeographic element of the Pacific. Many of these parakeets are, however, endangered, with ongoing conservation management hampered by the unresolved taxonomic status of some populations. We used modern and ancient DNA (mitochondrial DNA control region) to assess the taxonomy of the Auckland Islands populations of red-crowned (Cyanoramphus novaezelandiae novaezelandiae) and yellow-crowned (Cyanoramphus auriceps) parakeets. Our analyses show that both red-crowned and yellow-crowned parakeets on the Auckland Islands are nested within the mainland New Zealand diversity of the two species. However, we also found an orange-fronted parakeet (Cyanoramphus malherbi) mitochondrial DNA lineage within the genome of both of these species in the Auckland Islands population. Further sampling of historic orange-fronted parakeet museum skins showed that the orange-fronted morphotype is paraphyletic with respect to mitochondrial haplotype, which is probably caused by hybridisation or inc...

Many species of birds are considered pests in rural areas modified for agricultural production. We evaluated the abundance of four species of avian pests (Eared Dove (Zenaida auriculata), Monk Parakeet (Myiopsitta monachus), Picazuro Pigeon (Patagioenas picazuro) and Spot-winged Pigeon (P. maculosa)) in the Pampas of central Argentina. From 2006 to 2008, we surveyed 35 transects along secondary roads. All four species showed a response to the presence of exotic woodlots in rural areas. Monk Parakeets and the two pigeons were more likely to be found in woodlots with tall, perennial trees (Eucalyptus spp.), whereas Eared Doves were more likely to be found in woodlots with short, perennial trees (mainly species of Pinus and Casuarina). We did not detect any association between abundance of pest species and the presence of crops. These results suggest that management of exotic perennial trees in rural areas of the Pampas of central Argentina may provide a means of control of pest birds. Fil: Codesido, Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina Fil: Zufiaurre, Emmanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina Fil: Bilenca, David Norberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina

Beak and feather disease virus (BFDV) is a recognised key threat for the conservation of parrots globally, causing morbidity and mortality of individuals in susceptible species. We present findings from a survey in 2012 to investigate the presence of BFDV in wild New Caledonian parrots, including the endangered Ouvea Parakeet (Eunymphicus uvaeensis). Blood and feather samples from seven Ouvea Parakeets and 13 New Caledonian Rainbow Lorikeets (Trichoglossus haematodus deplanchii), and feathers from 15 New Caledonian Rainbow Lorikeets, five Horned Parakeets (Eunymphicus cornutus) and six New Caledonian Parakeets (Cyanoramphus saisseti) obtained from passive sampling, were tested by polymerase chain reaction (PCR) for BFDV. We identified a BFDV prevalence of 25% (95% CI 11-45%) in wild New Caledonian Rainbow Lorikeets, suggesting this species may act as a reservoir for persistence of BFDV in the wild, placing other parrots in New Caledonia at risk. All other parrot species tested negative for BFDV. New Caledonian Rainbow Lorikeets were introduced to Ouvea Island in the 1970s, potentially bringing BFDV with them. As Ouvea Parakeets are restricted to this small island, we strongly recommend surveillance screening for BFDV in this species to guide future biosecurity and conservation efforts, and further understand the risk posed by BFDV to threatened parrots.

Psittaciformes play a predominant role among the exotic species deliberately imported by humans all over the world, being the most popular bird pets. When released, they often establish naturalized populations, as they present a wide ecological plasticity and synanthropy. As for Tuscany, eight species have been reported (42.11% of those reported for the whole Italy), often near urban centers. Among those, two are possibly established and expanding: the rose-ringed parakeet (Psittacula krameri) and the monk parakeet (Myiopsitta monachus). This work aims to statistically reconstruct the actual extent of occurrence (EOO) of these two species through a fixed kernel method and their potential distribution through a bioclimatic envelope (BIOCLIM), using variables selected from the WORLDCLIM database, selected according to the ecological requirements of these species. BIOCLIM analysis suggests a possible expansion risk for monk parakeet and rose-ringed parakeet in Tuscany, as both species are presented with a hu...

Capsule The reproductive rate of Rose-ringed Parakeets in the UK was higher in 2001-2003 than previously estimated.Aim To measure reproductive rate and the factors affecting this in Rose-ringed Parakeets in England during a period of rapid expansion in population of this potential invasive species.Methods During 2001–2003, 108 nests were located and monitored in southwest London, southeast London and the Isle of Thanet. Nest survival using the Mayfield method, fledging success and the characteristics of the nest and surrounding vegetation were measured.Results The mean date of first egg was 26 March ± 1.3 days and the median clutch size was 4 eggs. Mayfield nest survival rate was 72%. Reproductive success was 1.4 ± 0.3 young fledged per nest. Parakeets bred predominantly in ash (Fraxinus) and oak (Quercus). Nest trees had a diameter at breast height (DBH) of 73.7 ± 4.7 cm (mean ± se).Conclusion Reproductive success in this parakeet was higher than previously estimated (0.8 young fledged per nest prior to ...

The Ring-necked Parakeet, Psittacula krameri, an invasive bird species in Oman was found to be feeding on the immature green pods of another invasive tree species, Prosopis juliflora, commonly known as Mesquite. This parakeet strips the pods and consumes the soft seeds within. The green pods collected from the base of trees were a mixture of stripped pods showing various levels of feeding damage and un-stripped pods without any damage. The percentage of stripped pods was significantly higher than that of un-stripped pods. The mean percentage number of pods in the five levels of feeding damage (10, 25, 50, 75 and 100%) significantly differed from each other. The un-stripped and undamaged pods indicate wasteful feeding activity. The comparison of the five levels of feeding damage (10, 25, 50, 75 and 100%) and the undamaged condition (0%) to the mean number of pods as percentages suggests that wasteful feeding is not a random event; the reasons for this relationship are discussed.

The monk parakeet (Myiopsitta monachus) is among the most important bird pest species causing damage to crops in Argentina and neighboring countries. Traditionally, lethal control has been applied for decreasing monk parakeet damage to crops, but objections are increasing and new methods are required. In this article, we examined farmers' preferences for management of monk parakeet damage to crops in relation to sociopsychological and sociodemographic factors. We conducted 111 personal interviews using face-to-face questionnaires. Farmers preferred reproductive and lethal control for decreasing monk parakeet damage to crops. Attitudes toward monk parakeets were related more strongly to preferences than any other factor considered in this study. Other important sociopsychological factors were perceived efficacy and previous knowledge about management strategies. Perceptions of magnitude of damage had little relation to preferences. Sociodemographic factors, such as age and education, differed in their rela...

Assessing use of resources across resource gradients and over time is necessary for determining factors that influence the natural distribution of birds. We analysed the pattern of availability of food resources, the use of food resources and the influence of food availability on reproduction and demography for the Austral Parakeet (Enicognathus ferrugineus) in two southern temperate forests of Argentine Patagonia. The abundance of Austral Parakeets in Nothofagus pumilio forests co-dominated by Araucaria araucana was generally higher and fluctuated more than abundance of populations in monospecific N. pumilio forest. This appears to be related to A. araucana providing a larger but more variable food resource. Austral Parakeets responded quickly to changing availability of resources by modifying their diet if alternative food resources were available, and reproductive success also increased when seed availability was high. We found mixed forests to be a unique and important habitat for Austral Parakeets in the northern part of their range, and conservation management should recognise this special role that mixed N. pumilio–A. araucana forests play in Austral Parakeet ecology.

Reliable survey methods for detection are critically important for the monitoring and management of exotic species. The eastern rosella (Platycercus eximius), a broad-tailed parakeet endemic to southeastern Australia, was introduced to New Zealand a century ago and is now geographically widespread. We studied the necessary timeframe for surveying the eastern rosella within its introduced range, testing the hypothesis that there are seasonal differences in the likelihood of detection. Although our comparisons were limited to surveys conducted during a single year, they are suggestive of an important impact of season on the survey duration required to detect eastern rosella confidently. Median latency until first detection was less during summer months (2.55 min) in comparison with winter months (11.2 min). Furthermore, 90% of first detections occurred within the first 13 min in summer surveys, compared with 22 min in winter. These results have implications for the design of surveys aiming to monitor rosell...

Avian malaria is recognised as a potential threatening factor for endangered New Zealand birds; nevertheless, analyses of its prevalence are few and often retrospective, following outbreaks in managed species. We conducted an opportunistic polymerase chain reaction (PCR)-based survey for Plasmodium on a remnant population of red-fronted parakeet (Cyanoramphus novaezelandiae) on Little Barrier Island alongside an analysis of haematology profiles as a first assessment of the effects of this parasite on parakeets. We sampled 22 parakeets and detected Plasmodium relictum DNA in nine samples (prevalence 40.9%; 95% CI = 20.49–61.51%). One successfully amplified sequence corresponded to P. relictum haplotype GRW4. Lymphocyte and heterophil to lymphocyte counts did not differ between PCR-positive and PCR-negative parakeets. However, it is unclear which state of the infection cycle the parakeets experienced during our sampling scheme. From a management perspective, our results indicate that translocation of parake...

Orange-fronted Parakeets Aratinga canicularis are widespread and common across their range. However, the ecology and habitat use are scarcely known. Observations of the nest site characteristics, diet, flock size, habitat movements, and local harvesting practices are reported in this study for Colima, Mexico, a site where the species occurs year-round. Characteristics of termitaria nest sites in deciduous oak and tropical semi-deciduous forests were compared. Nesting site selection did not differ between vegetation types, but some preference for higher and larger termitaria is suggested. Availability of suitable nesting sites is apparently not a limiting factor. Anecdotal reports from the local people and empirical observations of eggs and hatchlings by the author suggest a three-month extension of the breeding period to what is reported in the literature. A. canicularis was observed foraging on 25 plant species. Flock size and activity increased during the rainy season, and were reduced during the beginn...

Psittacine beak and feather disease (PBFD) is a highly infectious and potentially fatal viral disease of parrots and their allies caused by the beak and feather disease virus (BFDV). Abnormal feather morphology and loss of feathers are common clinical symptoms of the disease. PBFD also damages the lymphoid tissue and affected birds may die as a result of secondary bacterial or fungal infections. The disease is therefore of concern for conservation biologists and wildlife managers, as it is immunosuppressive and can become an additional threatening factor among critically endangered psittacines. We conducted a PCR-based screening for BFDV in a wild population of the Red-fronted Parakeet (Cyanoramphus novaezelandiae) on Little Barrier Island, New Zealand, during a translocation of this species. Fifty-four parakeets were captured and feather samples collected for molecular screening. We detected BFDV DNA from 15 individuals, but only two showed external signs attributable to PBFD, namely abnormal feather morphology or colouration, loss of feathers and haemorrhagic feathers. Our survey represents the first positive identification of BFDV in wild New Zealand endemic psittacines and confirms the risk of spread of the virus between wild populations within this global hotspot of endemic psittacine diversity.

Where seabird breeding colonies occupy forested habitats, unusual nutrient links between marine and terrestrial ecosystems can occur. In such circumstances, the dietary characteristics of forest birds inhabiting pristine seabird colonies have rarely been investigated. In this study, carried out in a mixed-species colony of petrels (Procellariiformes), we measured the stable isotopic (δ13C, δ15N) signatures of individual feathers of New Zealand Bellbirds (Meliphagidae : Anthornis melanura melanura; n = 6) and Red-crowned Parakeets (Psittacidae : Cyanoramphus novaezelandiae novaezelandiae; n = 15). The δ15N of Parakeet feathers encompassed a wide range, from +7.1‰ to –0.9‰. From the high maximum δ15N, relative to global temperate forest foliage, we conclude that some Parakeets were feeding within the petrel colony where they were captured. However, the low minimum δ15N, relative to foliage from the petrel colony, implies that Parakeet isotopic composition could not be fully explained by potential dietary items from the petrel colony. Bellbird δ15N (range +3.4‰ to +9.6‰) was more enriched than that of Parakeets, consistent with their higher trophic level, but also consistent with a dietary intake consisting of items from both within and beyond the petrel colony. Bellbird isotopic ratios were strongly enriched in δ13C, which could be explained only by consumption of invertebrates with marine isotopic enrichment. The marine invertebrates could have been associated with breeding petrels, or have come from the littoral zone near the site of capture. The importance for both species of food sources both inside and outside of petrel colonies implies that petrel colonies offer foraging opportunities for forest birds but that the birds also use non-colony areas. Consequently, petrel colonies are integral parts of the wider terrestrial landscape which they inhabit.

Screening for pathogenic micro-organisms is an essential component of translocationbased conservation management. While there are some data on pathogens in New Zealand passerines, little is known about the distribution and prevalence of pathogens infecting New Zealand Psittaciformes. We conducted a survey for pathogens of the vulnerable New Zealand endemic red-crowned parakeet Cyanoramphus novaezelandiae in two wild populations (Little Barrier Island and Raoul Island), and in a translocated population (Tiritiri Matangi Island). A total of 101 cloacal samples were tested for Salmonella and Yersinia. Of these, 82 samples were also tested for Campylobacter. None of these microorganisms were detected. Although our sampling effort was insufficient to detect a low prevalence of Campylobacter, modelling of minimum detectable prevalence of Salmonella and Yersinia indicates that these micro–organisms would have been detected if present as common or chronic conditions of redcrowned parakeets at these sites.

The Ring-necked Parakeet, Psittacula krameri, an invasive bird species, first appeared in Oman in 1950 but apparently died out and was not seen again until 1965, when it was re-introduced, probably through the escape or release of captive birds. From then on the species has gradually spread to its present distributional range that includes the Musandam Peninsula, all of the northern Batinah coast, the capital area of Muscat, occasional inland towns, and the area around Salalah in southern Oman. Its introduction to Masirah Island appears to have failed to establish a breeding population. The number of sightings of parakeets in Oman has increased from one per year in the late 1960’s to over 65 per year in 2001–2002. Despite the sightings of a few large flocks, flock size has remained fairly small, increasing from a mean of 1–2 individuals in the late 1960’s and early 1970’s to a mean of 7–8 for most years between 1985 and 2002. To date, the parakeets have been observed in areas that are inhabited b...

We conducted opportunistic observations on the diet of translocated orange-fronted parakeets (Cyanoramphus malherbi) on Maud Island to provide a first account of the diversity of food types ingested in the wild by this critically endangered species. Orange-fronted parakeets consumed fruits and leaves of 14 plant species as well as non–dietary items such as bark sticks and grit. Of dietary items, 96% were on plant species and 4% invertebrates. Of the plant species ingested 10% were non-natives. A major dietary component consisted of fruits and leaves of mahoe (Melicytus ramiflorus). In contrast to the only other published account of the diet of orange-fronted parakeets, invertebrates constituted a minor part of identified ingested items. This may be related to the different composition of vegetation at the study sites, the low parakeet population density during the time of our study and methodological restrictions during our survey. Our observations on undocumented food items add information about...

We revise the taxonomy of the two parakeet taxa in the psittaciform genus Eunymphicus – E. cornutus cornutus (Horned Parakeet) and E. c. uvaeensis (Ouvea Parakeet) – which are restricted to New Caledonia and the Loyalty Islands, in the south-western Pacific, and we investigate their relationship with the genera Cyanoramphus, considered traditionally as its closest related genus, and Prosopeia. We used three sets of characters to assess the level of differentiation between the Eunymphicus taxa: behaviour (vocalisations), morphology (biometrics and plumage coloration) and genetic (mitochondrial cytochrome b DNA sequence variation, 924 nucleotides). The analysis of vocalisations revealed significant differences, as did morphological analyses (size and number of feathers of the crest, size of the bill, and colour pattern of the head). Genetic distance between the Horned and Ouvea Parakeets is similar to that recorded between closely related species of Cyanoramphus and both taxa possess novel and diagnostic synapomorphic substitutions. From these genetic, behavioural and morphological data, the two Eunymphicus taxa should be considered separate species, a suggestion that is supported by ecological data as well as anecdotal data on hybridisation from captive birds. Our molecular data also support the traditional view that Cyanoramphus is the closest relative of Eunymphicus, with Prosopeia a sister group to this clade. The consistency with which Platycercus clusters next to the Cyanoramphus–Eunymphicus–Prosopeia grouping suggests that Platycercus may well be the next closest relative of this clade.

I studied Brotogeris chiriri abundance and foraging activity at a dry forest of the Urucum mountains in western Mato Grosso do Sul, Brazil, to evaluate their relationships with food resource production. Brotogeris chiriri abundance sharply increased during the early wet season (mainly October 2001) when it mostly foraged for fleshy fruits. At that time Protium heptaphyllum, one of the most common tree species, bore a large crop of fruits, the arils of which were extensively consumed by B. chiriri. Conversely, only a few parakeets were recorded foraging from the late wet to the late dry season, when dry fruit production predominated. The monthly pattern of parakeet abundance paralleled both its monthly pattern of foraging activity and fleshy fruit availability. Moreover, the variations in foraging activity were highly correlated to fleshy fruit production. Thus, data presented here evidenced the effect of both fruiting pulses and a common tree species that produced a large and ephemeral fruit crop, on the ...

Observations on the Alexandrine Parakeet (Psittacula eupatria), an alien species, at Keshavarzi Garden, Tehran, during 2000–2003, showed that the preferred food items were seeds of Pine (Pinus eldarica), Cypress (Cupressus sempervirens), Plane (Platanus orientalis), Elm (Ulmus carpinifolia), and fruits of Quince (Goldenapple) (Cydonia oblonga), Pear (Pyrus communis), Kaki (Persimmon) (Diospyros kaki). 78% and 59% of pine cones collected from two stations in the garden were certainly cut by P. eupatria. An estimation of the number of birds in Tehran gave at least 200 birds, based on a count in selected areas in winter 2003/2004. P. eupatria contributed 97% to the population of the two parakeets (P. eupatria and P. krameri) for some large parks, but only comprises c. 10% of the birds in some aviaries and pet shops.

The Norfolk Island Green Parrot and New Caledonian Red-crowned Parakeet were first described in the middle of the last century as subspecies of the widespread New Zealand Red-crowned Parakeet (C. novaezelandiae). Molecular phylogenetic analyses of all extant taxa of Cyanoramphus, except the Kermadec Island Parakeet (C. novaezelandiae cyanurus), reveal that the Norfolk Island Green Parrot, previously C. n. cooki, and New Caledonian Red-crowned Parakeet, previously C. n. saisetti, are highly divergent from all other members of the genus. We therefore elevate them to full species status as C. cooki and C. saisetti respectively. In our DNA sequencing study, two highly distinct, statistically well supported monophyletic clades were identified for both taxa under maximum likelihood, maximum parsimony and minimum evolution analyses. Both taxa are well separated from the C. novaezelandiae clade. The New Caledonian taxon is basal and may be the most ancient of all extant Cyanoramphus species. Levels of uncorrected percentage sequence divergences among mitochondrial (mtDNA) control region DNA sequences ranged from 7.80 to 9.55% between the New Caledonian Red-crowned Parakeet and other recognised congeneric species. The corresponding sequence divergence for the Norfolk Island Green Parrot from other Cyanoramphus species was 3.18—6.44%. Interspecific comparisons of Cyanoramphus species normally range from 2.03 to 7.93% (the latter two ranges do not include comparisons with the New Caledonian Redcrowned Parakeet). The mtDNA sequence data of both Norfolk Island and New Caledonian taxa fulfil criteria for their designation as species under the Phylogenetic Species Concept.

Controversy surrounds the taxonomic status of the Orange-fronted Parakeet (previously known as Cyanoramphus malherbi), officially a colour morph of the more common Yellow-crowned Parakeet C. auriceps. We analyse bill length and bill width measurements from 60 museum specimens of Orange-fronted Parakeet and 44 museum specimens of Yellow-crowned Parakeet. Male Orange-fronted Parakeets have shorter bills than male Yellow-crowned Parakeets — the difference between sample means is 0.7–0.8 mm. Power calculations show that others have most likely not seen the difference as significant because of small sample sizes. Our analysis illustrates a useful statistical technique for identifying morphological differences between two species where both species are sexually dimorphic but the sex of each individual is uncertain.

Ring-necked Parakeet nests are inaccessible and the species' breeding success has been poorly studied. The reproductive output of feral parakeet nests in southeast England was investigated in 1997 and 1998; 175 nestboxes were sited in known breeding areas and monitored, and natural nests at heights of 10 m or lower were examined using a video camera and torch. Only one nestbox was occupied by a mature pair and the nest failed; the lack of nestbox occupation suggests that nesting cavities were not limiting. Twelve natural nests were monitored from laying to near fledging: seven in west London and five in southeast London. Breeding success was lower than in the native range, at 0.8 fledglings per nest, due to lower hatching success rather than smaller clutch sizes. Mean reproductive output in the larger west London subpopulation was 1.2 fledglings per nest, while in the smaller subpopulation the mean was 0.25 fledglings per nest, although the difference was not significant. Possible reasons for low breeding...

The roseringed parakeet has been shown to exhibit a variable testicular responsiveness to both altered photoperiodic regimens and to treatment with melatonin during different phases of the annual gonadal cycle. Adult male roseringed parakeets were held under either natural photoperiods (NP), or long photoperiods (LP; 16L 8D), or short photoperiods (SP; 8L 16D) for a total period of 90 days. From day 46 onward, half of the total birds in each group were administered with the vehicle of melatonin, and the other birds were injected daily in the afternoon with melatonin (25 µg/ 100 g body wt.) till the end of the experiment. An identical experimental schedule was followed during the four different (preparatory, progressive, pre-breeding, and breeding) phases of the annual testicular cycle. The testicular activities in various bird groups were evaluated by volumetric, gravimetric, histometric and karyometric measurements, and by quantitative histological studies. The findings revealed that exogenous melatonin ...

Nest site selection in two hole‐nesting forest birds, mohua (yellowhead, Mohoua ochrocephala) and yellow‐crowned parakeet (Cyanoramphus auriceps), was investigated. Parakeets nested in a wide range of cavities ranging in size up to half a metre across. In contrast, mohua used small cavities that support the sides of their cup‐shaped nests. Most parakeet nests were found in red beech trees (Nothofagus fusca), which have many large cavities, and both species nested most often in trees >70 cm in diameter. Nest sites arc very numerous in our study area and are probably not limiting for either species in similar forests throughout Fiordland. However, neither species is likely to be able to nest in beech forests managed for timber production, in which most trees will be large enough for nesting only just before they are harvested. Although long‐tailed cuckoos (Euclynamvs taitensis) parasitise mohua nests and prey upon their nestlings, most mohua nest holes arc too small for cuckoos to lay eggs in. High...

Yellow‐crowned parakeets (Cyanoramphus auriceps) were studied in the Eglinton Valley, Fiordland, New Zealand. Productivity and mortality were closely related to cycles of beech seeding. Following a heavy beech mast, parakeets fed extensively on beech seed, and bred not only during their normal late summer breeding season, but right through the following winter, spring, and summer. During this time, the parakeet population increased dramatically, but in the following autumn it declined sharply, probably as a result of the depletion of beech seed and high rates of predation by stoats and perhaps other arboreal predators. Nesting parakeets are very vulnerable to stoat predation because they are hole‐nesters and because their chicks are very noisy just before fledging. Stoat trapping during a stoat irruption seemed to be of no benefit. Although trapping reduced stoat population density, enough stoats remained to prey on all accessible parakeet nests. More extensive trapping, and trapping when stoat n...

The breeding biology of the Monk Parakeet (Myiopsitta monachus monachus) was studied in Punta Blanca, central Argentina (34° 56’ S, 57° 39’ W). Observations on 9 communal nests (13 breeding chambers) were made dur‐ing 1988 and 1989. The median date of the first egg for each year was Hand 31 October (the median for 2 years was 16 October). Clutch size ranged from 5 to 12 eggs, averaging 6.9. Incubation took 23.6 days and hatching was asynchronous. Mean hatching success for clutches was 52.2%. Only 17% of the nestlings fledged. Only 8.9% of the total eggs laid resulted in fledglings. Predation by Opossums (Didelphis) and Black Rats (Rattus) was the main cause of mortality at nests (82%), but 17.9% of the nestling mortality was due to intraspecifics attacks, including sibling aggression.

The influence of melatonin, at a daily dose of 250 μg/100 g b.w. for ten consecutive days on morphological parameters of the pineal and adrenal cortex was investigated in two diverse avian species, Blossomheaded parakeet (Psittacula cyanocephala) and Indian Weaver bird (Ploceus philippinus). The results suggest that melatonin administered during the breeding phase caused stimulation of the adrenal cortex as evidenced from the significant increase in adrenocortical cord width and nuclear size in both avian species. However, the pineal gland in both species remained unaltered during this phase. On the contrary, melatonin given during the non‐breeding phase failed to alter the adrenal cortex but stimulated the pineal gland activity as evidenced from the significant increase in pinealocyte nuclear diameter in both species alike. It is suggested that melatonin can act as a reproductive‐phase dependent modulator of the pineal gland and adrenal cortex in these birds.

In this study we present a preliminary analysis of the structure of the complex multisyllabic warble song of the budgerigar Melopsittacus undulatus, a small, flock-living parakeet. We recorded eight male budgerigars from three different social groups, and one female. Budgerigar warble songs consist in long sequences of syllables that are diverse in structure, ranging from simple clicks to multinote, frequency-modulated musical-sounding syllables. We identified 42 syllable classes. Males shared a significantly greater percentage of their warble syllable-class repertoire with males in the same social group than with males in different groups. One male budgerigar preferentially imitated the syllables and temporal pattern of the abnormal warble of his cagemate (a male bird that had been reared in acoustic and social isolation) rather than the normal warble of other male budgerigars in adjoining cages. We discuss vocal imitation of social companions as a process of vocal learning, the potential role o...

Summary Haemagglutinating viruses were isolated from Australian parakeets and from aviary birds of the order Passeriformes. In all cases the affected birds showed symptoms of disease of the nervous system. One of the isolates, 449, has the physico‐chemical and biological properties of the paramyxo‐viruses. Comparative serological and animal‐experimental investigations suggested that this isolate could be a deviating strain of Newcastle disease virus.

Adult male blossomheaded parakeets were held under artificial long (22 h) and short (2 h) daily photoperiods for 45 days or 90 days at different phases of the annual gonadal cycle to investigate the influences of altered photoperiods on the behaviour of the adrenal medulla in these birds. Results of the quantitative estimation of epinephrine (E) and norepinephrine (NE), counting of the tinctorially differentiated E and NE cells and cytofluorescence of NE containing areas in the adrenal medulla, have indicated that adrenomedullary response to a particular light‐dark schedule is uniform throughout the reproductive cycle of the parakeet. It has been found that significant (P < 0.001) loss of NE occurs only after 45 days treatment of very short daily photoperiods (2 L: 22 D), but the adrenal medulla of the rest of the experimentally treated birds remains essentially similar to the chromaffin tissue of birds held parallely under natural photoperiods. The results indicate that long daily artificial dar...

Twenty-five parakeets were used as subjects in a study involving food-rewarded operant learning. The parakeet behaved essentially in the same way as other birds (Leghorn chicken, Wyandotte chicken, pigeon, quail, turkey, etc.) with respect to number of rewarded reactions to criterion and percentage of animals learning. Parakeets, however, learned significantly faster than all other birds. These findings have implications within the framework of evolutionary comparative learning hypotheses.

Histophysiological studies of the annual testicular events in an Indian Psittaciform bird, blossomheaded parakeet Psittacula cyanocephala, under natural environmental conditions revealed that the bird is a seasonal breeder with a single peak in a year. Active spermatogenesis takes place only during February and March, but maximum seasonal maturation of the Leydig cells occurs at least one month before the onset of active production of sperm. Comparison of the annual cycles of reproductive parameters with those of different climatological variables could show that duration of solar‐day, in contrast to ambient temperature and rainfall, through its cyclicity parallels, though in part, the gonadal cycle of male blossomheaded parakeet.

Annual histophysiological changes in the adrenal cortex of free‐living blossomheaded parakeets were studied in relation to the gametokinetic activities in the testes and periodic climatic variables to evaluate possible interrelationship, if any, between these endogenous and exogenous cyclic factors. Observations involving histometry, karyometry and lipid cytochemistry of adrenal cortex along with quantitative estimation of tissue cholesterol demonstrate the annual rhythmic pattern in the activity of adrenocortical tissue with an annual peak in February followed by regressive changes till August. Steady progressive changes towards annual peak occur only after November. Results show that the seasonality of the histophysiological features in the adrenal cortex coincides better with the periodic sexual activities of the bird than with any of the surrounding environmental factors.

Summary Infection of 1‐day‐old chicks with PMV‐3/parakeet/Netherlands/449/75 (449) by intramuscular, intranasal or contact routes resulted in severe impairment of growth in all groups compared to uninfected control birds. In the group infected intramuscularly with 449 virus 16/22 birds died within 14 days of infection. No clinical signs were seen in 6‐week‐old chickens infected with 449 by intramuscular, intranasal or contact routes. One‐day‐old chicks infected with a large dose of NDV‐B1 and one‐day‐old chicks placed in contact with these birds also showed significant impairment of growth compared to uninfected controls.

The adrenal medulla of male blossomheaded parakeets undergoes seasonal cycles in hormonal concentrations and in the relative number of epinephnne (E) and norepinephrine (NE) cells. NE, but not E, concentrations and cells become significantly (P < 0.001) higher in March than in September and October respectively. The one environmental factor that parallels, though only in part, the annual cycle of the chromaffin tissue is the photoperiod. However, consideration of the sexual periodicity of the parakeet leads to a tentative hypothesis to be tested that active gametogenesis in the testis is correlated with the periodic activity of the adrenal medulla.

House cats (Felis catus) were introduced to Herekopare Island, a mammal-free island of about 28 ha near Stewart Island, in about 1925. In winter 1970, the total population of 33 cats (20 males, 13 females) — a density of 1.2 cats/ha — was killed, mainly by trapping. Examination of stomach contents and scats showed that the cats fed mainly on petrels, supplemented by land birds and insects. The bird life of Herekopare Island was studied by H. Guthrie-Smith in 1911, L. E. Richdale in the early 1940s, and by New Zealand Wildlife Service staff in 1968 and 1970. Their accounts indicate that a vast breeding population of diving petrels and thousands of broad-billed prions were probably exterminated by the cats, though fairy prions and sooty shearwaters persisted. Among land birds, the yellow-crowned parakeet, robin, fernbird, brown creeper, Stewart Island snipe, and banded rail were exterminated. Two other species, the red-crowned parakeet and tomtit, probably disappeared but subsequently recolonised t...

SummaryAdult parakeets and pigeons, given doses of 60Co γ-rays in the 30-day lethal range, showed a peak of mortality at 9 to 11 days; and the early mortality (0 to 2 days after exposure), which is characteristic of the chicken, was not seen. Bone-marrow aplasia was the principal histological finding. When the duration of the exposure was increased from 4 to 480 min, there was a progressive decrease in dose effectiveness, but further increase of the exposure time to 1440 min led to no further decrease in dose effectiveness. These data are described in terms of time-dependent (reversible) and time-independent (irreversible) processes. A linear reversal of the time-dependent injury processes is in agreement with available data. The time constant associated with the reversible process in the parakeet and pigeon (τ = 295 ± 25 min) is in close agreement with the value reported earlier for the chick.

Additional new records and references from the literature are given for the Ring-nek-ked Parakeet, Psittacula krameri, in Egypt, Jordan, Israel and Syria. The species only succeeds in surviving in areas where there is little pressure from hunting, for example the city area of Cairo and several localities in Israel.

Damage caused by rose‐ringed parakeet to sunflower and maize, and by house sparrow to bajra and sorghum, have been estimated. As much as 33.37% of seeds in sunflower heads and 4.59% of cobs in maize were damaged by the parakeet. The overall loss in sorghum ranged from 11.75 to 132.00 ear heads per 1.2 X 1.5 m area. In bajra fields, 39.85% of ears were affected.