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1.
Parasitol Res ; 122(8): 1787-1794, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37233815

RESUMEN

Swifts (Apodidae) are an unusual group of birds that spend most of their lives in flight, landing only when breeding. Although this aerial lifestyle greatly reduces their likelihood of being bitten by vectors and infected by vector-born parasites, swifts can still be heavily infested during breeding by nest-based vectors such as louse flies (Hippoboscidae). Here, we investigated host, vector, and vector-borne parasite relationships in the three most widespread swift species in the Western Palearctic (WP): common swifts (Apus apus), pallid swifts (A. pallidus), and alpine swifts (Tachymarptis melba), their nest-based louse flies (Crataerina pallida and C. melbae) and avian haemosporidians (genera Haemoproteus, Plasmodium, and Leucocytozoon). Studies of haemosporidian infections in Apodidae remain limited, with clear evidence of infection found to date in just four Neotropical and one Australasian species. The possible role of louse flies in transmitting haemosporidian infections has never been tested in swifts. We assessed the occurrence of haemosporidian infection by PCR screenings of DNA from blood samples from 34 common swifts and 44 pallid swifts from Italy, and 45 alpine swifts from Switzerland. We also screened 20 ectoparasitic louse flies present on 20 birds and identified them by both morphological features and cytochrome oxidase subunit 1 (COI) barcodes. Our results provide no evidence of haemosporidian infection in the 123 swifts tested or in the two louse fly species we identified. Our findings are consistent with available knowledge showing no haemosporidian occurrence in WP swift species and that the most likely infection route for these highly aerial species (via louse fly ectoparasites during nesting) is unlikely.


Asunto(s)
Anoplura , Enfermedades de las Aves , Dípteros , Infestaciones Ectoparasitarias , Haemosporida , Animales , Dípteros/parasitología , Enfermedades de las Aves/parasitología , Infestaciones Ectoparasitarias/parasitología , Aves/parasitología , Haemosporida/genética , Filogenia
2.
Sci Data ; 10(1): 239, 2023 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-37100803

RESUMEN

Colonial waterbirds, a major biodiversity element occurring in the core of ultra-anthropized Europe, are ideal indicators of the wellness of inland wetlands. Nonetheless, there is a critical knowledge gap in their trend and population status. We present an uninterrupted 47 years-long dataset of the breeding populations of 12 species of colonial waterbirds (Ardeidae, Phalacrocoracidae, Plataleidae, Threskiornitidae) throughout a 58,000 km2 agricultural region in the higher Po basin (NW Italy). A trained team of collaborators censused with standardized field techniques the number of nests of each species at 419 colonies in the 1972-2018 period, summing up a total of 236,316 records. Data cleaning and standardization were performed for each census year, ensuring robust and consistent data. This dataset is among the largest ever collected for a guild of European vertebrates. It has already been used to describe the factors influencing population trends, and still offers opportunities to explore a wide range of key ecological processes such as biological invasions, global change consequences and biodiversity impact of agricultural practices.


Asunto(s)
Aves , Censos , Humedales , Animales , Biodiversidad , Conservación de los Recursos Naturales , Italia
3.
Ecol Evol ; 10(14): 7916-7928, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32760574

RESUMEN

Several species of migratory swifts breed in the Western Palearctic, but they differ in reproductive traits and nonbreeding areas explored in Africa. We examined survival and recapture probabilities of two species of swifts by capture-mark-recapture data collected in northern Italy (Pallid Swift Apus pallidus in Carmagnola, Turin, and Common Swift Apus apus in Guiglia, Modena) in the breeding season (May-July). Apparent survival rates were relatively high (>71%), comparable to other studies of European swifts, but showed marked annual variations. We used geolocators to establish the exact wintering areas of birds breeding in our study colonies. Common Swifts explored the Sahel zone during migration and spent the winter in SE Africa, while the Pallid Swifts remained in the Sahel zone for a longer time, shifting locations southeast down to Cameroun and Nigeria later in winter. These movements followed the seasonal rains from north to south (October to December). In both species, we found large yearly differences in survival probabilities related to different climatic indices. In the Pallid Swift, wintering in Western Africa, the Sahel rainfall index best explained survival, with driest seasons associated with reduced survival. In the Common Swift, wintering in SE Africa, the El Niño-Southern Oscillation (ENSO) cycle performed significantly better than Sahel rainfall or North Atlantic Oscillation (NAO). Extreme events and precipitation anomalies in Eastern Africa during La Niña events resulted in reduced survival probabilities in Common Swifts. Our study shows that the two species of swifts have similar average annual survival, but their survival varies between years and is strongly affected by different climatic drivers associated with their respective wintering areas. This finding could suggest important ecological diversification that should be taken into account when comparing survival and area use of similar species that migrate between temperate breeding areas and tropical wintering areas.

6.
PLoS One ; 14(1): e0210268, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30608988

RESUMEN

The Common Chiffchaff Phylloscopus collybita is an abundant, polytypic Palearctic bird. Validity of some of its subspecies is controversial and birds from some parts of the species range remain unclassified taxonomically. The relationships among populations from different geographic areas have not been sufficiently explored with molecular data. In this study we analyzed the relationships among the four species in the 'chiffchaff complex' (Common Chiffchaff, Iberian Chiffchaff P. ibericus, Canary Islands Chiffchaff P. canariensis and Mountain Chiffchaff P. sindianus), and the patterns of intraspecific geographic variation in the mtDNA ND2 gene and intron 9 of the Z-linked aconitase gene (ACO1I9) across the Common Chiffchaff range, including a recently discovered population breeding on Mt. Hermon (Anti-Lebanon mountains). Our data supported the monophyly of the chiffchaff complex and its current systematics at the species level. Within the Common Chiffchaff, the Siberian race P. c. tristis was the most differentiated subspecies and may represent a separate or incipient species. Other Common Chiffchaff subspecies also were differentiated in their mtDNA, however, lineages of neighboring subspecies formed wide zones of introgression. The Mt. Hermon population was of mixed genetic origin but contained some birds with novel unique lineage that could not be assigned to known subspecies. All Common Chiffchaff lineages diverged at the end of the Ionian stage of Pleistocene. Lineage sorting of ACO1I9 alleles was not as complete as that of mtDNA. Chiffchaff species were mostly distinct at ACO1I9, except the Common and Canary Islands Chiffchaffs that shared multiple alleles. An AMOVA identified geographic structure in Common Chiffchaff ACO1I9 variation that was broadly consistent with that of mtDNA ND2 gene. The genetic and other data suggest the chiffchaff complex to be a group of evolutionarily young taxa that represent a paradigm of 'species evolution in action' from intergrading subspecies through to apparently complete biological speciation.


Asunto(s)
Aconitato Hidratasa/genética , ADN Mitocondrial/genética , Evolución Molecular , Variación Genética , NADH Deshidrogenasa/genética , Passeriformes/genética , Animales , Haplotipos , Filogeografía
7.
Proc Biol Sci ; 285(1889)2018 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-30355709

RESUMEN

Hewitt's paradigm for effects of Pleistocene glaciations on European populations assumes their isolation in peninsular refugia during glacial maxima, followed by re-colonization of broader Europe during interstadials. This paradigm is well supported by studies of poorly dispersing taxa, but highly dispersive birds have not been included. To test this paradigm, we use the dunnock (Prunella modularis), a Western Palaearctic endemic whose range includes all major European refugia. MtDNA gene tree, multilocus species tree and species delimitation analyses indicate the presence of three distinct lineages: one in the Iberian refugium, one in the Caucasus refugium, and one comprising the Italian and Balkan refugia and broader Europe. Our gene flow analysis suggests isolation of both the Iberian and Caucasus lineages but extensive exchange between Italy, the Balkans and broader Europe. Demographic stability could not be rejected for any refugial population, except the very recent expansion in the Caucasus. By contrast, northern European populations may have experienced two expansion periods. Iberia and Caucasus had much smaller historical populations than other populations. Although our results support the paradigm, in general, they also suggest that in highly dispersive taxa, isolation of neighbouring refugia was incomplete, resulting in large super-refugial populations.


Asunto(s)
Distribución Animal , Variación Genética , Refugio de Fauna , Pájaros Cantores/fisiología , Animales , Europa (Continente) , Haplotipos , Filogenia , Filogeografía , Análisis de Secuencia de ADN , Pájaros Cantores/genética
8.
PLoS One ; 11(7): e0158203, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27368056

RESUMEN

In recent years, the "forest-specialist" pine marten Martes martes has been reported to also occur also in largely fragmented, lowland landscapes of north-western Italy. The colonization of such an apparently unsuitable area provided the opportunity for investigating pine marten ecological requirements and predicting its potential south- and eastwards expansion. We collected available pine marten occurrence data in the flood plain of the River Po (N Italy) and relate them to 11 environmental variables by developing nine Species Distribution Models. To account for inter-model variability we used average ensemble predictions (EP). EP predicted a total of 482 suitable patches (8.31% of the total study area) for the pine marten. The main factors driving pine marten occurrence in the western River Po plain were the distance from watercourses and the distance from woods. EP suggested that the pine marten may further expand in the western lowland, whilst the negligible residual wood cover of large areas in the central and eastern plain makes the habitat unsuitable for the pine marten, except for some riparian corridors and the pine wood patches bordering the Adriatic coast. Based on our results, conservation strategies should seek to preserve remnant forest patches and enhance the functional connectivity provided by riparian corridors.


Asunto(s)
Agricultura , Bosques , Modelos Estadísticos , Mustelidae , Pinus , Animales , Conservación de los Recursos Naturales , Ecosistema , Humanos
9.
Zootaxa ; 4032(1): 127-33, 2015 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-26624343

RESUMEN

We report the occurrence of the recently-described Stiphrornis pyrrholaemus in the Makokou area, northeastern Gabon, more than 600 kilometers NE from its type locality, in areas covered by dense primary to secondary forest. The previous records of Stiphrornis from the same area were referred to S. xanthogaster. We confirm this attribution on the basis of museum specimens. Although several recent sources treat all Stiphrornis as a single species, our findings strongly suggest the sympatric coexistence of two Stiphrornis species and thus that they should be treated as separate species under the Biological Species Concept.


Asunto(s)
Passeriformes/clasificación , Simpatría , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Ecosistema , Femenino , Gabón , Masculino , Tamaño de los Órganos , Passeriformes/anatomía & histología , Passeriformes/genética , Passeriformes/crecimiento & desarrollo
10.
Zookeys ; (456): 139-46, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25709525

RESUMEN

The Italian natural history museums are facing a critical situation, due to the progressive loss of scientific relevance, decreasing economic investments, and scarcity of personnel. This is extremely alarming, especially for ensuring the long-term preservation of the precious collections they host. Moreover, a commitment in fieldwork to increase scientific collections and concurrent taxonomic research are rarely considered priorities, while most of the activities are addressed to public events with political payoffs, such as exhibits, didactic meetings, expositions, and talks. This is possibly due to the absence of a national museum that would have better steered research activities and overall concepts for collection management. We here propose that Italian natural history museums collaborate to instate a "metamuseum", by establishing a reciprocal interaction network aimed at sharing budgetary and technical resources, which would assure better coordination of common long-term goals and scientific activities.

11.
Environ Entomol ; 37(5): 1145-53, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19036193

RESUMEN

Many capture-recapture studies on adult dragonflies have found male-biased sex ratios. However, few have estimated survivorship of males and females separately from data on frequency of recaptures in the field. Even when daily survival and capture probabilities are estimated separately, controversies can arise on whether sex biases in local survival are to be attributed to mortality or permanent emigration from the study site. The knowledge of male and female movements, assessed on an appropriate scale (i.e., within and outside the breeding site), can help address this issue. In this paper, we performed a 4-yr capture-recapture study of two Libellula fulva Müller populations in northwest Italy. Cormack-Jolly-Seber models were used to get unbiased estimates of demographic parameters (daily survival and capture probabilities, sex ratio, mean life span, and population size). Movement parameters were measured directly by georeferencing encounters. Moderate differences in survival, with males surviving better than females, were found in one population and not in the other, suggesting that these differences are not an inherent characteristic of the species. In the population with lower female survival, females were not more vagile than males, thus indicating their lower survival was caused by actual mortality rather than to emigration. In the population with no survival differences between males and females, marked males outnumbered females, but estimated sex ratios were approximately 1:1 or female biased. Therefore, raw field data were misleading because they led to underestimates of the more elusive sex and overestimates of the more detectable one (males). Survival and movement differences detected in the two populations are discussed in the framework of local environmental and demographic factors.


Asunto(s)
Ecosistema , Insectos , Razón de Masculinidad , Animales , Femenino , Italia , Masculino , Dinámica Poblacional
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