Mistakes in the analysis of exotic species establishment: source pool designation and correlates of introduction success among parrots (Aves: Psittaciformes) of the world

Aim To evaluate the effect of mis‐specifying the correct comparison of species pools in the study of species characteristics associated with the biological introduction of exotic species. Methods We use a high quality data set on biological introductions of parrots (Aves: Psittaciformes). These data allow us to examine relationships between life history traits and probability of successful transition through an introduction stage when the species pool is both correctly and incorrectly specified. Results For the establishment of introduced parrot species, nearly half of the predictor variables showed different patterns of significance when an incorrect pool was specified. Multivariate analysis identified entirely different sets of variables as independent predictors of establishment success, depending on the species pool used. Correct pool specification identified that introduced parrot species have been more likely to establish if they have broader diets and are more sedentary. Main conclusions Conclusions from the analysis of biological introductions are likely to depend on the specification of the species pool for such analyses. In the analysis of parrot introductions, this was particularly apparent in establishment success following release. Further studies that analyse the introduction pathway need to examine the effects of pool mis‐specification so that the generality of our results can be assessed.     

Founder populations and the current status of exotic parrots in South Africa

Parrots (families Psittacidae and Cacatuidae) are one of the most threatened taxa of birds, with a combination of threats to wild populations, including capture for the cage bird market, habitat modification and destruction, persecution, disease, and threats from introduced species. As a result of the group's popularity as a cage bird, and the transport of vast numbers of individuals across the globe (both legally and illegally), the establishment of populations beyond their natural ranges has likely been enhanced. This review reports on c. 30 parrot species that have been observed outside of their natural ranges in South Africa, most likely derived, and supplemented, from both intentional and unintentional releases. Of these, the Rose-ringed Parakeet Psittacula krameri and at least one Agapornis species have become established as breeding wild populations. Like other invasive species they may pose threats to local biodiversity; however, all are strongly associated with major urban centres where significant changes to natural biota have already occurred.     

The influence of spatial resolution on macroecological patterns of range size variation: a case study using parrots (Aves: Psittaciformes) of the world

Aim To assess the extent to which the resolution at which geographical range sizes are measured influences macroecological patterns in this variable. Location Global. Methods Data on the geographical ranges of parrot species were digitized, and a Geographic Information System used to produce nine range size estimates for each species using different degrees of spatial resolution. The inter‐correlation of these estimates was then compared, together with their patterns of covariation with population size, body mass and migratory behaviour (across species and controlling for phylogeny), their pattern of phylogenetic correlation, and the frequency distributions of the different measures. Results Strong correlations exist among all nine range size measures across species, albeit that measures of similar spatial resolution are more strongly correlated. All measures show similar patterns of covariation with population size, body mass and migratory behaviour, and similar patterns of phylogenetic correlation. The skewness of frequency distributions increases towards zero as the resolution of the range size measure declines. Main conclusions The results of macroecological analyses are little affected by the resolution with which geographical range sizes are calculated, at least for the parrots of the world. Previously published studies based on crude measures of range size would be unlikely to have produced markedly different conclusions had they used more refined range size metrics.     

Herbivores and the success of exotic plants: a phylogenetically controlled experiment

In a field experiment with 30 locally occurring old‐field plant species grown in a common garden, we found that non‐native plants suffer levels of attack (leaf herbivory) equal to or greater than levels suffered by congeneric native plants. This phylogenetically controlled analysis is in striking contrast to the recent findings from surveys of exotic organisms, and suggests that even if ‘enemy release’ does accompany the invasion process, this may not be an important mechanism of invasion, particularly for plants with close relatives in the recipient flora.     

Chromosome studies of 8 species of parrots of the families Cacatuidae and Psittacidae (Aves: Psittaciformes)

The karyotypes of 7 species of Psittaciformes new to cytology are described: Cacatua galerita, Calyptorhynchus magnificus and Probosciger aterrimus of the Cacatuidae, and Ara macao, A. ararauna, Amazona viridigenalis and Psittrichas fulgidens of the Psittacidae. For reasons of comparison the karyotype of Melopsittacus undulatus is also described. These karyotypes are compared to 8 psittaciform karyotypes previously recorded. There is a remarkable heterogeneity of karyotypes in the Psittaciformes. Nevertheless, it seems possible to recognize Cacatua, Calyptorhynchus and probably also Probosciger (Cacatuidae) by their karyotypes as a clearly related group. The karyotypes of these cacatuids also bear some resemblance to that of Loriculus (Psittacidae). The psittacid genera Amazona, Ara, Nestor, Melopsittacus, Psittacula, Psittacus and Psittrichas are karyologically heterogeneous, but their karyotypes show certain relationships. The karyotype of Brotogeris is very different from those of other psittacids.     

Biological invasions and scientific objectivity: Reply to Cassey et al. (2005)

Abstract We disagree with the assertion that recent human‐caused invasions differ substantially from historic natural invasions in their magnitudes and impacts on ecological processes. The position that exotic species are inherently ‘bad’ and should be eradicated is an ethical judgement, usually based on the naturalist fallacy or xenophobic prejudice; it is not a scientific judgement. The role of scientists in studying invasive species should be to gather, interpret and communicate information as accurately and objectively as possible.     

Hindlimb myology of the monk parakeet (Aves,Psittaciformes)

We studied the hindlimb myology of the monk parakeet (Myiopsitta monachus). Like all parrots, it has zygodactyl feet enabling perching, climbing, hanging, moving easily among trees, and handling food. Muscles were described and weighed, and physiological cross‐sectional area (PCSA) of four flexors and one extensor was calculated. In comparison to other muscles, the M. tibialis cranialis and the M. fibularis brevis show increased development and high PCSA values, and therefore, large potential force production. Also, a large proportion of muscle mass was involved in flexing the digits. We hypothesize that these muscle traits are associated with the arboreal locomotion and food manipulation habits. In the monk parakeet, the M. extensor digitorum longus sends a branch to the hallux, and the connection between the M. flexor digitorum longus and the M. flexor hallucis longus is type I (Gadow's classification). We reaffirm the presence of the M. ambiens as a plesiomorphic condition that disappears in most members of the order. Among Psittaciformes, the M. fibularis brevis is stronger and the M. fibularis weaker in arboreal species than in basal terrestrial ones (e.g., Strigops). J. Morphol. 275:732–744, 2014. © 2014 Wiley Periodicals, Inc.     

Peristerophila nestoriae,a new species of quill mite of the family Syringophilidae (Acariformes: Prostigmata) parasitizing New Zealand Kaka Nestor meridionalis (Gmelin) (Psittaciformes: Strigopidae)

A new species of quill mite of the family Syringophilidae (Acariformes: Prostigmata), Peristerophila nestoriae sp. nov. from New Zealand Kaka, Nestor meridionalis (Gmelin) (Psittaciformes: Strigopidae) is described. This new species is morphologically similar to Peristerophila falcophila [Skoracki M, Hromada M, Kaszewska K, Unsoeld M. 2018. Peristerophila falcophila sp. nov., a new species and first record of quill mites (Acariformes: Syringophilidae) parasitizing birds of the order Falconiformes. Acta Parasitologica. 63:744–749. https://doi.org/10.1515/ap-2018-0088], and differs from it as follow: the stylophore is 130–140 long (vs. 150–160 long); the propodonotal shield bear bases of setae ve, si, and c1 (vs. only ve and si on the propodonotal shield); fan-like setae p′ and p″ of legs III and IV with 11–13 tines (vs. 10 tines); the lengths of setae ag2 40–50 (vs. 55–70). Our finding is the first record of the presence of syringophilid mite on host of the family Strigopidae and first report of the member of Peristerophila on psittaciform birds. So far, the syringophilids mites have not been found in New Zealand.

LSID: urn:lsid:zoobank.org:pub:FB0C5B37-DF42-428C-8C81-8FA56EA67504     

A new species of the feather mite genus Titanolichus Gaud & Atyeo, 1996 (Acari: Astigmata: Pterolichidae) from the endangered orange-bellied parrot Neophema chrysogaster (Aves: Psittaciformes) from Australia

Abstract  Titanolichus seemani sp. n., a new species of the genus Titanolichus Gaud & Atyeo, 1996, is described from a museum skin of the endangered orange-bellied parrot Neophema chrysogaster (Latham) (Aves: Psittaciformes) from Australia. We also redescribe the type species Titanolichus chiragricus (Mégnin & Trouessart) from the ground parrot Pezoporus wallicus (Kerr), provide a key for all known species of Titanolichus and point out some problems in the systematics of this genus.     

Determinants of vertebrate invasion success in Europe and North America

Species that are frequently introduced to an exotic range have a high potential of becoming invasive. Besides propagule pressure, however, no other generally strong determinant of invasion success is known. Although evidence has accumulated that human affiliates (domesticates, pets, human commensals) also have high invasion success, existing studies do not distinguish whether this success can be completely explained by or is partly independent of propagule pressure. Here, we analyze both factors independently, propagule pressure and human affiliation. We also consider a third factor directly related to humans, hunting, and 17 traits on each species' population size and extent, diet, body size, and life history. Our dataset includes all 2362 freshwater fish, mammals, and birds native to Europe or North America. In contrast to most previous studies, we look at the complete invasion process consisting of (1) introduction, (2) establishment, and (3) spread. In this way, we not only consider which of the introduced species became invasive but also which species were introduced. Of the 20 factors tested, propagule pressure and human affiliation were the two strongest determinants of invasion success across all taxa and steps. This was true for multivariate analyses that account for intercorrelations among variables as well as univariate analyses, suggesting that human affiliation influenced invasion success independently of propagule pressure. Some factors affected the different steps of the invasion process antagonistically. For example, game species were much more likely to be introduced to an exotic continent than nonhunted species but tended to be less likely to establish themselves and spread. Such antagonistic effects show the importance of considering the complete invasion process.     

The comparative importance of species traits and introduction characteristics in tropical plant invasions

Aim We used alien plant species introduced to a botanic garden to investigate the relative importance of species traits (leaf traits, dispersal syndrome) and introduction characteristics (propagule pressure, residence time and distance to forest) in explaining establishment success in surrounding tropical forest. We also used invasion scores from a weed risk assessment protocol as an independent measure of invasion risk and assessed differences in variables between high‐ and low‐risk species. Location East Usambara mountains, Tanzania. Methods Forest transect surveys identified species establishing in disturbed and intact forest. Leaf traits (specific leaf area and foliar nutrient concentrations) were measured from leaves sampled in high‐light environments. Results A leaf traits spectrum was apparent, but species succeeding or failing to establish in either disturbed or intact forest were not located in different parts of the spectrum. Species with high invasion risk did not differ in their location on the leaf trait spectrum compared with low‐risk species but were more likely to be bird/primate‐dispersed. For 15 species establishing in forest quadrats, median canopy cover of quadrats where seedlings were present was correlated with a species value along the leaf trait spectrum. Species establishing in disturbed forest were planted in twice as many plantations and were marginally more likely to be bird‐ or primate‐dispersed than species failing to become established in disturbed forest. Establishment in intact forest was more likely for species planted closer to forest edges. Main conclusions Leaf and dispersal traits appear less important in the colonization of tropical forest than introduction characteristics. It appears, given sufficient propagule pressure or proximity to forest, alien species are much more likely to establish independently of leaf traits or dispersal syndrome in continental tropical forests.     

The parrots (Aves: Psittaciformes) from the Middle Miocene of Sansan (Gers,Southern France)

The occurrence of Archaeopsittacus sp. (Psittaciformes) in the fossil deposits of Sansan (France) is reported, testifying to a survival of this genus in the Middle Miocene, as Archaeopsittacus verreauxi was described from the Early Miocene of Saint-Gérand-le-Puy (France) and was recorded only from its type locality. The data discussed here indicate the presence of two parrot species from Sansan, as it is the type locality of another parrot species, Pararallus dispar, only known from this locality. The differences between the humeri of these two taxa are described in detail, together with the differences from the other European fossil parrot species. The presence of more than one species of parrot in the same locality is not rare, but in Europe it is recorded in Sansan for the second time. Evidence for parrots also confirms the paleoenvironmental reconstruction of Sansan, as parrots are primarily arboreal species. Archaeopsittacus also represents one of the few common elements between the Early and Middle Miocene European bird assemblages.     

The evolution of the Indian Ocean parrots (Psittaciformes): extinction, adaptive radiation and eustacy

Parrots are among the most recognisable and widely distributed of all bird groups occupying major parts of the tropics. The evolution of the genera that are found in and around the Indian Ocean region is particularly interesting as they show a high degree of heterogeneity in distribution and levels of speciation. Here we present a molecular phylogenetic analysis of Indian Ocean parrots, identifying the possible geological and geographical factors that influenced their evolution. We hypothesise that the Indian Ocean islands acted as stepping stones in the radiation of the Old-World parrots, and that sea-level changes may have been an important determinant of current distributions and differences in speciation. A multi-locus phylogeny showing the evolutionary relationships among genera highlights the interesting position of the monotypic Psittrichas, which shares a common ancestor with the geographically distant Coracopsis. An extensive species-level molecular phylogeny indicates a complex pattern of radiation including evidence for colonisation of Africa, Asia and the Indian Ocean islands from Australasia via multiple routes, and of island populations ‘seeding’ continents. Moreover, comparison of estimated divergence dates and sea-level changes points to the latter as a factor in parrot speciation. This is the first study to include the extinct parrot taxa, Mascarinus mascarinus and Psittacula wardi which, respectively, appear closely related to Coracopsis nigra and Psittacula eupatria.     

New feather mites of the family Pterolichidae (Acari: Pterolichoidea) from parrots (Aves: Psittaciformes) in Australia

Abstract Seven new feather mite species of the family Pterolichidae are described from various Australian parrots: Apexolichus lathami sp. n. from the swift parrot, Lathamus discolor (Shaw); Titanolichus platycerci sp. n. and Rhytidelasma punctata sp. n. from the pale-headed rosella, Platycercus adscitus (Latham); R. striata sp. n. from the Australian king-parrot, Alisterus scapularis (Lichtenstein); Lorilichus stenolobus sp. n. and Lorilichus curvilobus sp. n. from the rainbow lorikeet, Trichoglossus haematodus (Linnaeus); Psittophagus galahi sp. n. from the galah, Eolophus roseicapillus (Vieillot). We give a brief overview of taxonomic studies of pterolichid mites living on Psittaciformes, and discuss the main diagnostic characters of different generic groups of these mites.     

Out of the Bassian province: historical biogeography of the Australasian platycercine parrots (Aves,Psittaciformes)

Schweizer, M., Güntert, M. & Hertwig, S. T. (2012). Out of the Bassian province: historical biogeography of the Australasian platycercine parrots (Aves, Psittaciformes). —Zoologica Scripta, 42, 13–27. Aridification from mid‐Miocene onwards led to a fragmentation of mesic biomes in Australia and an expansion of arid habitats. This influenced the diversification of terrestrial organisms, and the general direction of their radiations is supposed to have been from mesic into drier habitats. We tested this hypothesis in the platycercine parrots that occur in different habitats in Australia and also colonized Pacific islands. We inferred their temporal and spatial diversification patterns using a Bayesian relaxed molecular clock approach based on three nuclear and two mitochondrial genes and model‐based biogeographic reconstructions. The Bassian biota was found to be the centre of origin of platycercine parrots and diversification within two of their three clades coincided with the beginning of aridification of Australia. The associated habitat changes may have catalysed their radiation through adaptation to arid environments and vicariance because of the fragmentation of non‐arid habitats. The small oceanic islands of Melanesia contributed as stepping stones for the colonization of New Zealand from Australia.     

A multilocus molecular phylogeny of the parrots (Psittaciformes): support for a Gondwanan origin during the cretaceous

The question of when modern birds (Neornithes) first diversified has generated much debate among avian systematists. Fossil evidence generally supports a Tertiary diversification, whereas estimates based on molecular dating favor an earlier diversification in the Cretaceous period. In this study, we used an alternate approach, the inference of historical biogeographic patterns, to test the hypothesis that the initial radiation of the Order Psittaciformes (the parrots and cockatoos) originated on the Gondwana supercontinent during the Cretaceous. We utilized broad taxonomic sampling (representatives of 69 of the 82 extant genera and 8 outgroup taxa) and multilocus molecular character sampling (3,941 bp from mitochondrial DNA (mtDNA) genes cytochrome oxidase I and NADH dehydrogenase 2 and nuclear introns of rhodopsin intron 1, tropomyosin alpha-subunit intron 5, and transforming growth factor ss-2) to generate phylogenetic hypotheses for the Psittaciformes. Analyses of the combined character partitions using maximum parsimony, maximum likelihood, and Bayesian criteria produced well-resolved and topologically similar trees in which the New Zealand taxa Strigops and Nestor (Psittacidae) were sister to all other psittaciforms and the cockatoo clade (Cacatuidae) was sister to a clade containing all remaining parrots (Psittacidae). Within this large clade of Psittacidae, some traditionally recognized tribes and subfamilies were monophyletic (e.g., Arini, Psittacini, and Loriinae), whereas several others were polyphyletic (e.g., Cyclopsittacini, Platycercini, Psittaculini, and Psittacinae). Ancestral area reconstructions using our Bayesian phylogenetic hypothesis and current distributions of genera supported the hypothesis of an Australasian origin for the Psittaciformes. Separate analyses of the timing of parrot diversification constructed with both Bayesian relaxed-clock and penalized likelihood approaches showed better agreement between geologic and diversification events in the chronograms based on a Cretaceous dating of the basal split within parrots than the chronograms based on a Tertiary dating of this split, although these data are more equivocal. Taken together, our results support a Cretaceous origin of Psittaciformes in Gondwana after the separation of Africa and the India/Madagascar block with subsequent diversification through both vicariance and dispersal. These well-resolved molecular phylogenies will be of value for comparative studies of behavior, ecology, and life history in parrots.