Dynamics of infection of Fringilla coelebs chaffinch nestlings with feather mites (Acari: Analgoidea)

A process of infecting the chaffinch nestlings Fringilla coelebs with three analgoid feather mites, Analges passerinus L., 1758, Monojoubertia microphylla (Robin, 1877), and Pteronyssoides striatus (Robin, 1977), commonly occurred on this bird species was investigated. 15 nests contained totally 65 nestlings, from 2 to 6 individuals in a brood, have been examined from the day of hatching till 11th day. Observations were held in the neighbourhood of the bird banding station "Rybachy" (Russia, Kaliningrad Province) in June of 1982. Number of mites on alive nestlings taken temporarily from their nest was counted by means of binocular lens under the magnification x12.5 and x25. The nestlings receive the mites from the chaffinch female during the night time, when the female sits together with the young birds and heats them. In the condition of this prolonged direct contact the mites migrate from the female onto the nestlings. As it was shown in our study of seasonal dynamics of mites on the chaffinch (Mironov, 2000), the chaffinch female only gives its mites to young generation and looses about three quarter of its mite micropopulation during the nesting period (June), hile in the chaffinch males the number of mites continues to increase during all summer. The infections with three feather mite species happen in the second part of the nestling's stay in the nest. The starting time of this process, its intensity, and sex and age structure of mite micropopulations on the nestlings just before their leaving the nest are different in the mite species examined. These peculiarities of feather mite species are determined by the biology of examined species, and first of all by their morphological characteristic and specialisation to different microhabitats, i.e. certain structural zones of plumage. Pteronyssoides striatus (Pteronyssidae) is rather typical mite specialised to feathers with vanes. In adult birds with completely developed plumage this species occupies the ventral surface of the big upper coverts of primary flight feathers. This species appears on the chaffinch nestlings in a significant number on 7th day. The mites occupy the basal parts of primary flight feathers represented in that moment by the rods only. They sit on practically open and smooth surface of this microhabitat, which is uncommon for them, because the vanes of the big upper coverts are not yet open and also represented by thin rods. During the period of the last 5 days (from 7 to 11th day) the mean number of mites per one nestling increases from 2.3 +/- 0.5 to 17.1 +/- 1.8 mites. Just before the day, when the nestling leave the nest, the tritonymphs absolutely predominate (82.4%) in the micropopulation of P. striatus. Analges passerinus (Analgidae) is specialised to live in the friable layer formed by numerous not-engaged thread barbles of the down feathers and basal parts of the body covert feathers. Mites have special hooks on legs used for hard attaching to the barbles and for fast moving in the friable layer of feathers. On the chaffinch nestlings, these mites appear usually on 8th day, when the rod-like body covert feathers begin to open on apices and form short brushes; however some individuals occur on the skin of nestlings even on 6th day. The mean number of mites per nestling on the 11th day reaches 16.5 +/- 1.4 individuals. The micropopulation of A. passerinus is represented on the nestlings mainly by the females (45.5%), tritonymphs (23.6%) and males (11.5%). Monojobertia microphylla (Proctophyllodidae) is a typical dweller of feathers with large vanes. Mites of this species commonly occupy the ventral surface of primary and secondary flight feathers and also respective big upper covert feathers of wings. M. microphylla appears on the nestlings in a significant number (7.1 +/- 1.2 mites) on 9th day, only when the primary flight feathers already have short vanes about 10 mm in length. In next three days the number of mites increases very fast and reaches on 11th day 60.3 +/- 5.7 mites per nestling. In the micropopulation of this species, the tritonymphs count 38.3%, and the quota of males and females is 25.3% each. The migration of this species goes most intensively, than in two other species. An analitic selection of logistic curves shows, that the increasing of mite number during the process of infection with three mite species may be most adequately described by the sigmoid curves with clearly recognizable levels of saturation, which can be theoretically reached. Indeed, the number of mite individuals being able to migrate onto the nestlings is limited by their number on a respective chaffinch female. In a contrast, the increasing of plumage indices, for instance the length of flight feathers, has almost linear character during the period of observation. The beginning of mite migration is determined by the development of respective microhabitats in the plumage of nestlings, or at least by the development of certain structure elements of plumage, where mites are able to attach for a while, before that moment, when the nestlings will develop the plumage completely and begin to fly. In three mite species examined, the process of infection was performed by older stages, namely by the imago and/or tritonymphs. This can be explained by two reasons. On the one hand, the older stages are most active in their movement, resistible and able to survive successfully on new host individuals. On the other hand, the older stage are ready for the reproduction or will be ready after one moulting. The older stages of mites can quickly create a large and self-supporting micropopulations on the birds, therefore this strategy ensures a successful subsequent existence of the parasite species. In cases, when mites (A. passerinus, M. microphylla) migrate into the respective microhabitats structurally corresponding to their normal microhabitats on adult birds, the micropopulations of these mite species include a significant or dominant quota of females and males. When the normal microhabitat is not yet formed, feather mites migrate into neighboring structure elements of plumage, where they can survive and wait for the development of normal microhabitat, to which they are well adapted. Therefore, in the case of P. striatus, its micropopulations on the chaffinch nestlings are represented mainly by the tritonymphs.     

Four new feather mite species of the genus Proctophyllodes Robin(Astigmata:Proctophyllodidae) from China

Four new species of the feather mite genus Proctophyllodes are described from the birds of the order Passeriformes in China:P.flexuosa sp.nov.from Eophona migratoria Hartert(Chongqing),P.brevis sp.nov.from Passer montanus(Linnaeus)(Anhui and Chongqing),P.garrula sp.nov.from Garrulax poecilorhynchus Gould(Anhui),P.canora sp.nov.from Garrulax canorus(Linnaeus)(Guizhou).     

The first find of the feather mite from Apionacaridae family (Astigmata: Analgoidea) on the passerines ( Passeriformes)

A representative of the family Apionacaridae is recorded from the passerine birds Passeriformes for the first time. Fringillosphaera bochkovi gen. n., sp. n. is described from the chaffinch Fringilla coelebs (Fringillidae). The new genus obtains main diagnostic characters as follows. Vertical setae vi absent. Prodorsal shield free from scapular sheilds and epimerites Ia. Humeral sheilds present. Epimerites I convergent, connected by sclerotized plate. Lateral setae f2 and pseudanal setae ps3 absent. Coxal fields I-IV sclerotized. In male: legs IV present, genital apparatus at level of trochanters IV, genital arch with divergent branches. Epiandrium absent. Coxal setae 3a absent. Morphological peculiarities, host associations and phylogenetic relationships of the family Apionacaridae are briefly discussed. It is suggested that this family represents and ancient and relic phylogenetic branch, which had split rather early from the common ancestor of the superfamily Analgoidea in the period of formation of the Neognathae birds.     

Noise, predation risk compensation and vigilance in the chaffinch Fringilla coelebs

Background noise should in theory hinder detection of auditory cues associated with approaching danger. We tested whether foraging chaffinches Fringilla coelebs responded to background noise by increasing vigilance, and examined whether this was explained by predation risk compensation or by a novel stimulus hypothesis. The former predicts that only inter-scan interval should be modified in the presence of background noise, not vigilance levels generally. This is because noise hampers auditory cue detection and increases perceived predation risk primarily when in the head-down position, and also because previous tests have shown that only interscan interval is correlated with predator detection ability in this system. Chaffinches only modified interscan interval supporting this hypothesis. At the same time they made significantly fewer pecks when feeding during the background noise treatment and so the increased vigilance led to a reduction in intake rate, suggesting that compensating for the increased predation risk could indirectly lead to a fitness cost. Finally, the novel stimulus hypothesis predicts that chaffinches should habituate to the noise, which did not occur within a trial or over 5 subsequent trials. We conclude that auditory cues may be an important component of the trade-off between vigilance and feeding, and discuss possible implications for anti-predation theory and ecological processes.     

Evolution of the chaffinch, Fringilla coelebs, on the Atlantic Islands

Chaflinches have differentiated within the last million years on the Canary Islands and the Azores. All island populations differ more from mainland relatives than from each other. The characteristics of island birds are large body size, short wings, long legs and beaks, and blue dorsal colour. Beak depth and width have increased on the Azores but not on the Canaries. As a consequence the Azores chaffinch has evolved more in the direction of the Canary Island F. teydea than have Canary Island chaflinches. Character displacement may have occurred on the Canaries. Most of the evolutionary shifts are not predicted from a knowledge of clinal variation on the mainland. Populations have differentiated more on the Canaries than on die Azores, but are less variable regardless of whether ecologically restricted (by teydea) or not. Similarly, within the Azores archipelago the most differentiated populations are die least variable. On the Azores, but not on the Canaries, differentiation increases with isolation, whereas wimin-population variation decreases with isolation and increases with elevation. A model for diese patterns is proposed in terms of gene flow between populations, which reduces differentiation but enhances variation, and directional selection and random genetic processes which have the opposite effects.     

Testing the flexibility of song type bout duration in the chaffinch, Fringilla coelebs

Many songbird species with small song type repertoires repeat each type a few times before switching to the next. Thus, their singing style may constrain their ability to switch. However, the proximate causation of song type switching is poorly understood. We exposed male chaffinches to (nonoverlapping) playbacks of single renditions of their own songs rather than a series of songs, thus stimulating them with a single external auditory event. The most prominent effect of the playback was an increase in the duration of the current song type bout. If the song type played back was different to that the subject was singing at the time, bout duration increased less than if it was of the same song type. The short-term changes induced by the playback suggest that the auditory input increases the motivational level for a particular song type. In the chaffinch this results in a delayed switch rather than in song type matching as a reaction to acoustic stimulation by conspecific song. Copyright 2000 The Association for the Study of Animal Behaviour.     

Genetic diversity and morphological variation of the common chaffinch Fringilla coelebs in the Azores

We present new insights into the genetic diversity and phylogeography of the common chaffinch Fringilla coelebs from the Azores, based on sequences of mitochondrial and nuclear genes from 44 individuals and an outgroup/comparison of 44 birds from Madeira, the Canary Islands and the Continental Western Palearctic. To understand the level of concordance between the genetic data and morphometric variability we analysed eight morphometric characters from 413 adult living birds from all the Azores islands and compared the population genetic distances with quantitative morphometric traits. Our results indicate the occurrence of gene flow among the common chaffinch populations in the archipelago revealing the lack of current genetic structure within it and the existence of two co‐occurring lineages. Results also indicate the existence of morphometric differences among islands that could be due to ecological features instead of island isolation. This study also confirms the genetic distance among the common chaffinch populations within Macaronesia and between these archipelagos and the Continental Western Palearctic.     

Microsatellite loci isolation in the Canarian common chaffinch (Fringilla coelebs) and their utility in other Canarian finches

The taxonomic classification of the common chaffinch (Fringilla coelebs) that inhabits the Canary Islands has been under debate for decades, mainly due to the absence of nuclear DNA analyses. In this study we describe the isolation and characterization of ten microsatellite loci (AAAG, AAAT and GT) from a La Palma specimen using an enrichment protocol. Two loci were monomorphic in the populations analysed (La Gomera and La Palma), but the remaining ones presented 2 or more alleles, with an average of 11.63 alleles per locus and an average observed heterozygosity of 0.735 (n = 44). All loci were tested for their utility in other Canarian populations and other finch species.     

Three new species of feather mite of the genus Proterothrix Gaud, 1968 (Analgoidea: Proctophyllodidae: Pterodectinae) from passerines in Meghalaya,North East India

Three new species of the feather mite subfamily Pterodectinae Park & Atyeo, 1971 are described from passerines of the family Muscicapidae Fleming and Leiothrichidae Swainson in India (Meghalaya, East Jaintia Hills District): Proterothrix daberti n. sp. from the White-tailed Robin Cinclidium leucurum (Hodgson), P. khahnarensis n. sp. from the Blue Whistling-Thrush Myophonus caeruleus (Scopoli) (Passeriformes: Muscicapidae) and P. indica n. sp. from the Nepal Fulvetta Alcippe nipalensis (Hodgson) (Passeriformes: Leiothrichidae). P. daberti and P. khahnarensis belong to the megacaula species group and differ from one another (and from the third species belonging to the group) in having a distinct ornamentation of dorsal shields in both sexes: with small ovate and circular lacunae in P. daberti and with big ovate lacunae in P. khahnarensis. Proterothrix indica belongs to the paradoxornis species complex (wolffi species group) and differs from the other four species of the complex in having the lateral margins of prodorsal shield with incisions extending to bases of setae se in both sexes. Males of this species have opisthosomal lobes with acute apices.     

Adaptive phenotypic and genomic divergence in the common chaffinch (Fringilla coelebs) following niche expansion within a small oceanic island

According to models of ecological speciation, adaptation to adjacent, contrasting habitat types can lead to population divergence given strong enough environment-driven selection to counteract the homogenizing effect of gene flow. We tested this hypothesis in the common chaffinch (Fringilla coelebs) on the small island of La Palma, Canary Islands, where it occupies two markedly different habitats. Isotopic (δ¹³C, δ¹⁵N) analysis of feathers indicated that birds in the two habitats differed in ecosystem and/or diet, and analysis of phenotypic traits revealed significant differences in morphology and plumage colouration that are consistent with ecomorphological and ecogeographical predictions respectively. A genome-wide survey of single-nucleotide polymorphism revealed marked neutral structure that was consistent with geography and isolation by distance, suggesting low dispersal. In contrast, loci putatively under selection identified through genome-wide association and genotype-environment association analyses, revealed a marked adaptive divergence between birds in both habitats. Loci associated with phenotypic and environmental differences among habitats were distributed across the genome, as expected for polygenic traits involved in local adaptation. Our results suggest a strong role for habitat-driven local adaptation in population divergence in the chaffinches of La Palma, a process that appears to be facilitated by a strong reduction in effective dispersal distances despite the birds' high dispersal capacity.     

A highly repeated FCP centromeric sequence from chaffinch (Fringilla coelebs: Aves) genome is revealed within interchromosomal connectives during mitosis

A highly repeated FCP (Fringilla coelebs PstI element) sequence was localized by FISH in centromeric regions of all chromosomes of the chaffinch. Besides, FISH signal was found also in interchromosomal connectives linking centromeres of non-homologous chromosomes in mitotic cells. The presence of DNA in the connectives was confirmed by immunostaining with anti-dsDNA antibodies as well as in experiments on nick-translation and random primed labeling in situ. Non-denaturing FISH with FCP probe and random primed labeling of non-denatured chromosomes resulted in fluorescence signal on both centromeres and intercentromeric connectives, thus providing evidence for the availability of single-strand DNA tracts in FCP sequence. It is suggested that the highly repeated FCP centromeric sequence may be respondible for interconnection of mitotic chromosomes and may by involved in nuclear architecture maintenance in the chaffinch.     

Monomers of a satellite sequence of chaffinch (Fringilla coelebs L., Aves: Passeriformes) genome contains short clusters of the TTTAGGG repeat

A novel repeated sequence of chaffinch (Fringilla coelebs) designated as GS was isolated from genomic DNA after in vitro amplification of satellite DNA sequences using GSP-PCR technique. The proportion of this repeat in the chaffinch genome constitutes about 2%. Monomers are 176 to 199 bp in size and contain a short cluster of the TTAGGG telomeric tandem repeat. The oligomer of the telomeric hexanucleotide is flanked by the sequences that are significantly different in different monomers. The GS sequences are organized as tandemly repeated units and located in a number of chromomycin-positive blocks on the long arms of macrochromosomes 1, 2, 3, 5, and 6, as well as on several microchromosomes. The sequences homologous to the GS satellite of chaffinch were not found in the genomes of redwing (Turdus iliacus) and house sparrow (Passer domesticus).     

Interaction between seed crypsis and habitat structure influence patch choice in a granivorous bird, the chaffinch Fringilla coelebs

Food abundance is an important determinant in habitat and patch selection but food accessibility and detectability is less often considered. Foraging on more cryptic seeds may increase predation risk by increasing the length of head down periods. Habitat structure may interact with this as birds are less able to detect predators with their head lowered in riskier obstructed habitats. We investigated patch choice in chaffinches Fringilla coelebs foraging in obstructed and open habitats and artificially manipulated the search times of seeds by colouring them either yellow or black. One trial consisted of a choice between the conspicuous seed in the open patch, and the cryptic seed in the obstructed patch; in the second trial the treatments were reversed. Individuals were more willing to forage in the obstructed habitat when the yellow seeds were present (43% of pecks made in the obstructed patch) than when the black seeds were present (18% of pecks in the obstructed patch). Differences in search time are likely to explain this result: yellow seeds were located almost twice as fast (1.26±0.60 seconds) as black ones (2.36±0.88 seconds). This experiment shows that individual foraging decisions may be influenced not only by food abundance but by the properties of individual food items (in this case seed crypsis) and the structure of the habitat they are present in.     

The feather mite (Astigmata) fauna of some passerine birds (Passeriformes) in the south of Western Siberia

Feather mites (Astigmata) are specialized parasites living on the plumage and skin of birds. The paper presents data on infestation of some passerines (Passeriformes) by feather mites in the south of Western Siberia (Omsk and Tyumen Provinces). We found 24 species of feather mites belonging to the families Analgidae, Dermoglyphidae, Pteronyssidae, Trouessartiidae, and Proctophyllodidae on 16 bird species. Among them, 19 species are common parasites of the passerine birds examined; five species were detected on atypical hosts. Ten mite species were recorded for the first time on the passerine species examined. Analysis of the distribution of abundant and common mite species on their hosts has demonstrated that the majority of the bird parasites possess a specific distribution pattern in the host plumage with preference for certain feather types. We have also obtained new data on host associations of several mite species.     

Neighbour-stranger song discrimination in the Chaffinch(Fringilla coelebs)

Zusammenfassung In 3 Versuchsreihen (playback-Experimente) wurde an 40 territorialen Buchfinken- (Vokales Repertoire, 2–3 Strophentypen) die Reaktion auf die Gesänge von Nachbarn und Fremden gemessen. Es ergaben sich schwache Hinweise auf eine stärkere Reaktion gegenüber Fremdgesang, allerdings waren die Resultate hier weniger klar als von anderen Arten berichtet wird. Wir nehmen an, daß die individuelle Erkennung von Artgenossen bei Arten, deren Gesangsmuster mehrere Strophentypen umfaßt, weniger stark entwickelt ist als bei solchen Arten, deren Repertoire nur einen Strophentyp pro aufweist.     

Phylogeny and co-speciation in feather mites of the subfamily Avenzoariinae (Analgoidea: Avenzoariidae)

A cladistic analysis of phylogenetic relationships is carried out for the feather mite subfamily Avenzoariinae. The analysis is made at two different taxonomic levels, for 19 genera of the all family Avenzoariidae and for taxa of species rank for the Avenzoaria and Bychovskiata generic groups. A subsequent comparative analysis of phylogenetic hypotheseis for the subfamily Avenzoariinae and recently accepted phylogenetic hypotheses of the shorebirds Charadriiformes indicates co-speciation of feather mites with their hosts. As a result of the comparative analysis it is suggested, that the subfamily Avenzoariinae originated from an ancestor of the order Charadriiformes and co-speciated with this host order. The expected pattern of parallel evolution is disturbed by different evolutionary events, such as host shifts, extinction of mites and differential evolutionary rates of mite lineages in different phyletic branches of feather parasites.