Dispersal in a metapopulation of the critically endangered Danube Clouded Yellow butterfly Colias myrmidone : implications for conservation

Colias myrmidone has suffered a dramatic decline in Europe, and now its occurrence is restricted to just a few countries. We investigated one of the last viable metapopulations (Knyszyn Forest, NE Poland), where the butterfly is almost completely dependent on forestry, inhabiting some clearings and young tree plantations rich in larval food plants (Chamaecytisus ruthenicus) and nectar resources. Intensive mark-recapture studies were performed in 2017 on eight occupied patches separated by 0.5-5km. The overall population size of imagoes in the second brood was calculated at about 750 individuals. Sex ratio was shown to be well-balanced and average residency was estimated at 5.6 days. Dispersal occurred mostly between neighbouring patches, and isolation of patches contributed to the high mortality of emigrants. The average distance covered during dispersal was significantly higher for males. However, females left small patches much more readily than males. These patches were probably used only as stepping stone' sites in dispersal. Restricted dispersal could be related to barriers created by forest stands but it is also not excluded that individuals living in an isolated metapopulation become increasingly sedentary and our results are an early warning sign. The most distant local population was clearly isolated, with hardly any immigration from the other populations. To maintain a network of more stable habitat patches some clearings should be left deforested and appropriately managed. However this goal is difficult to achieve under the current forestry rules and therefore (re)creation of habitats on other available open areas should be considered

What keeps "living dead" alive : demography of a small and isolated population of Maculinea (= Phengaris) alcon

Small and isolated populations are prone to future extinctions and thus perceived as living dead'. Although generally considered to be of low conservation value, their existence can still enhance species survival at the landscape scale through improving the connectivity of other populations and facilitating some (even if little) gene flow. We investigated the demography and genetic status of a tiny and highly isolated local population of Maculinea (=Phengaris) alcon near its distribution margin with the aim of identifying the features that allow it to persist. The study comprised intensive mark-recapture, surveys of Gentiana pneumonanthe foodplants and butterfly eggs laid on them, as well as genetic analyses. The population has been found to be characterised by low genetic diversity and estimated at only a few tens of individuals. The foodplant availability turned out to be the most obvious factor limiting M. alcon abundance. Nevertheless, the life expectancy of adult butterflies is fairly long, and their flight period very short, implying that most individuals occur within the same time window. Together with the relatively little protandry observed, i.e. almost synchronous emergence of males and females, this increases the chances of random mating among the individuals. Moreover, the butterflies move freely across the core habitat fragment. All things concerned, the effective population size is presumably not much lower than the recorded population size. Our findings provide guidelines for pinpointing those among "living dead" populations that are likely to be the most persistent and thus worth conservation efforts aimed at preserving them

Changes in song organization of common songbird species breeding in anthropogenic noise polluted habitats

Wydział BiologiiHałas antropogeniczny jest uznawany za jedno najintensywniejszych zaburzeń w środowisku, negatywnie wpływających na komunikację dźwiękową ptaków, która jest szczególnie istotna dla ich przetrwania. Ptaki potrafią modyfikować różne parametry śpiewu w odpowiedzi na podwyższony poziom hałasu, aczkolwiek ostatnie badania proponują alternatywne wyjaśnienia zaobserwowanych zmian jak typ siedliska czy zmienność osobnicza. Głównym celem pracy była ocena zmian zachodzących w strukturze i czasowej organizacji śpiewu ptaków żyjących w miastach, różniących się sposobem śpiewu oraz jego złożonością. Uzyskane wyniki pokazują, iż zięba oraz piecuszek nie modyfikują śpiewu w środowisku zanieczyszczonym hałasem antropogenicznym. W przypadku zięby zaobserwowano ciekawe zależności między wielkością repertuaru, tempem śpiewu i czasem trwania serii śpiewu, które mogą być przydatne podczas określania jakości samca. Aczkolwiek wyniki z eksperymentów z playbackami sugerują podwyższoną czujności u osobników żyjących w środowisku zanieczyszczonym hałasem antropogenicznym. Analiza śpiewu piecuszka wykazała, iż samce śpiewające w grupach charakteryzują się większą złożonością śpiewu, co może mieć związek z jakością środowiska. W przypadku śpiewaka zaobserwowano istotne różnice w parametrach śpiewu między miejską i leśną populacją, co może być reakcją na wyższy poziom natężenia hałasu antropogenicznego.Urban ecosystems have been shown to influence many aspects of bird vocal communication, which can become increasingly demanding under noisy conditions. Birds are able to adjust their song to ambient noise level, however those changes are not straightforward, and can be due to factors such as habitat type or phenotypic flexibility. The main purpose of this work was the assessment of the habitat type induced changes in structure and temporal organisation in bird song of species that differ significantly in singing behaviour and song complexity, which can be differently influenced by anthropogenic noise. Results show that chaffinch and the willow warbler do not modify their song in response to anthropogenic noise. In case of the chaffinch relations were found between repertoire size, song rate and bout duration, that indicate male quality. Playback experiment shown that the response of territorial birds differed significantly with bout duration and tested male motivational state, and that anthropogenic noise increases vigilance. Willow warbler males increased their song complexity with the presence of other singing males in neighbourhood, which can suggest habitat quality. However, song of thrush song differs significantly between urban and forest habitats, which can be a example of adaptations to acoustic communication in noisy urban environments.Praca powstała w wyniku realizacji projektu badawczego o nr 2013/09/N/NZ8/03204 finansowanego ze środków Narodowego Centrum Nauk

Changes in song organization of common songbird species breeding in anthropogenic noise polluted habitats

Wydział BiologiiHałas antropogeniczny jest uznawany za jedno najintensywniejszych zaburzeń w środowisku, negatywnie wpływających na komunikację dźwiękową ptaków, która jest szczególnie istotna dla ich przetrwania. Ptaki potrafią modyfikować różne parametry śpiewu w odpowiedzi na podwyższony poziom hałasu, aczkolwiek ostatnie badania proponują alternatywne wyjaśnienia zaobserwowanych zmian jak typ siedliska czy zmienność osobnicza. Głównym celem pracy była ocena zmian zachodzących w strukturze i czasowej organizacji śpiewu ptaków żyjących w miastach, różniących się sposobem śpiewu oraz jego złożonością. Uzyskane wyniki pokazują, iż zięba oraz piecuszek nie modyfikują śpiewu w środowisku zanieczyszczonym hałasem antropogenicznym. W przypadku zięby zaobserwowano ciekawe zależności między wielkością repertuaru, tempem śpiewu i czasem trwania serii śpiewu, które mogą być przydatne podczas określania jakości samca. Aczkolwiek wyniki z eksperymentów z playbackami sugerują podwyższoną czujności u osobników żyjących w środowisku zanieczyszczonym hałasem antropogenicznym. Analiza śpiewu piecuszka wykazała, iż samce śpiewające w grupach charakteryzują się większą złożonością śpiewu, co może mieć związek z jakością środowiska. W przypadku śpiewaka zaobserwowano istotne różnice w parametrach śpiewu między miejską i leśną populacją, co może być reakcją na wyższy poziom natężenia hałasu antropogenicznego.Urban ecosystems have been shown to influence many aspects of bird vocal communication, which can become increasingly demanding under noisy conditions. Birds are able to adjust their song to ambient noise level, however those changes are not straightforward, and can be due to factors such as habitat type or phenotypic flexibility. The main purpose of this work was the assessment of the habitat type induced changes in structure and temporal organisation in bird song of species that differ significantly in singing behaviour and song complexity, which can be differently influenced by anthropogenic noise. Results show that chaffinch and the willow warbler do not modify their song in response to anthropogenic noise. In case of the chaffinch relations were found between repertoire size, song rate and bout duration, that indicate male quality. Playback experiment shown that the response of territorial birds differed significantly with bout duration and tested male motivational state, and that anthropogenic noise increases vigilance. Willow warbler males increased their song complexity with the presence of other singing males in neighbourhood, which can suggest habitat quality. However, song of thrush song differs significantly between urban and forest habitats, which can be a example of adaptations to acoustic communication in noisy urban environments.Praca powstała w wyniku realizacji projektu badawczego o nr 2013/09/N/NZ8/03204 finansowanego ze środków Narodowego Centrum Nauk

Habitat-related differences in song structure and complexity in a songbird with a large repertoire

Abstract Background Urbanisation has been shown to influence many aspects of animal vocal communication. Much attention has been paid to anthropogenic noise, which is often described as one of the most challenging disturbances for urban dwellers. While a large body of literature describes associations between vocal behavior of avian populations and background noise level, most of these studies were conducted on species with relatively simple songs and small repertoire sizes. This study focuses on the song thrush, Turdus philomelos, a common Eurasian songbird with a complex singing style and large syllable repertoire. Our objective was to determine whether frequency, repertoire and temporal organisation of song parameters vary between birds inhabiting urban and adjacent forest habitats in which ambient noise levels differ. Results Songs of urban males were found to be more complex than in conspecifics from natural forest populations. Urban dwellers possessed greater syllable repertoires and repeated syllable sequences more often. In addition, they used a smaller proportion of whistles and a higher proportion of twitter syllables when singing compared to the nonurban males. Moreover, we found significant differences in the minimum and peak frequency of the whistle syllable between studied populations. Conclusions These findings may be an example of adaptation of acoustic communication in noisy urban environments, but we also discuss other possible explanations. We emphasize the need for further investigation into the relationships between birdsong and habitat characteristics, male quality, population density and ambient noise level in populations occupying urban and nonurban habitats

Spectrogram of great spotted woodpecker drumming.

<p>(a) Spectrogram represents one roll of drumming. (b) Pulse Train Analysis window with visible strokes within drumming roll (first six stroke-to-stroke durations are indicated). Spectrogram settings: FFT length = 512; Frame size = 75%, Window = Hamming.</p

Descriptive statistics of analysed characteristics of great spotted woodpecker drumming.

<p>Descriptive statistics of analysed characteristics of great spotted woodpecker drumming.</p

Vocal individuality in drumming in great spotted woodpecker—A biological perspective and implications for conservation

<div><p>Animals—including conservation biologists—use acoustic signals to recognise and track individuals. The majority of research on this phenomenon has focused on sounds generated by vocal organs (e.g., larynx or syrinx). However, animals also produce sounds using other parts of the body, such as the wings, tail, legs, or bill. In this study we focused on non-syrinx vocalisation of the great spotted woodpecker, called drumming. Drumming consists of strokes of a bill on a tree in short, repeated series, and is performed by both males and females to attract mates and deter rivals. Here, we considered whether the great spotted woodpecker’s drumming patterns are sex-specific and whether they enable individual identification. We recorded drumming of 41 great spotted woodpeckers (26 males, 9 females, 6 unsexed). An automatic method was used to measure the intervals between succeeding strokes and to count strokes within a drumming roll. The temporal parameters of drumming that were analysed here had lower within- than between-individual coefficients of variation. Discriminant function analyses correctly assigned 70–88% of rolls to the originating individual, but this depended on whether all individuals were analysed together or split into males and females. We found slight, but significant, differences between males and females in the length of intervals between strokes—males drummed faster than females—but no difference in the number of strokes within a roll. Our study revealed that temporal patterns of drumming in the great spotted woodpecker cannot be used for unambiguous sex determination. Instead, discrimination among individuals may be possible based on the intervals between strokes and the number of strokes within a roll. Therefore, it is possible that differences in the temporal parameters of drumming may be used by birds to identify each other, as well as by researchers to aid in census and monitoring tasks.</p></div

Spectrogram of great spotted woodpecker drumming.

<p>(a) Spectrogram represents one roll of drumming. (b) Pulse Train Analysis window with visible strokes within drumming roll (first six stroke-to-stroke durations are indicated). Spectrogram settings: FFT length = 512; Frame size = 75%, Window = Hamming.</p