Varied Tit Research Articles

Multiple ornaments: trade-offs and redundancy in signalling functions in male and female varied tits (Sittiparus varius)

Abstract Signals conveyed by ornaments can be indicators in the process of sexual selection. Specifically, signals may be superimposed on each other to represent an individual’s quality, convey different information, or offer redundant information. As much of the research in this area has focused on relationships between diverse signals in males, those of females have largely been overlooked. From 2022 to 2023, we tested whether three traits, namely acoustic (song display) and visual ornaments (patch size and carotenoid-based plumage coloration), and morphology (wing and tail length), were interrelated in males and whether visual ornaments and morphology were interrelated in females in a wild population of varied tits (Sittiparus varius). We found that males with brighter and more reddish plumage sang at lower maximum and minimum frequencies, with narrower bandwidths and lower frequency peaks. Similarly, a negative correlation between tail length and carotenoid-based plumage coloration was observed in both sexes. Furthermore, a positive relationship was found between signals within traits. These results highlight the trade-offs in signals between different traits, as well as the consistency within the same traits.

Ecological Determinants of Inter-Island Distributions through Occasional Dispersal of Two Closely Related Species, Varied Tit and Cinereous Tit, in the Volcanic Izu Archipelago, Japan

Inspired by ecologists R. H. MacArthur and E. O. Wilson, who pioneered the use of islands as ideal model systems for researching the formation and maintenance of biodiversity, we studied two sympatric passerine bird species on a volcanic archipelago, in Japan. We focused on the occupancy and co-occurrence of Varied Tit Sittiparus varius and Cinereous Tit Parus cinereus, both members of the Parus guild, on the Izu Islands. Their populations range from being stable, and co-occurring, to being temporally unstable (with local extinctions, invasions, and species replacement) and even totally absent. Using results from several surveys carried out on the islands over the last 60 years, and our own contemporary surveys, we tested the ecological drivers of inter-island occupancy through occasional dispersal of these two species. We found that both species had positive relationships with island size and vegetation diversity, while Cinereous Tit exhibited a negative associating with distance to the mainland (Honshu, Japan). Cinereous Tit was also negatively correlated with Varied Tit, but their co-occurrence was positively associated with island size, connectivity, and vegetation diversity. We suspect that resource constraints play a significant role in the distributions of the two species on the islands. Varied Tit is dominant over Cinereous Tit, but Cinereous Tit is able to utilize a wider range of habitats and resources. We also discuss the potential for a competition-colonization trade-off for the two species on the islands.

Nest predation risk influences the Varied Tit’s life history strategy in response to temperature and precipitation

Life history strategy is of great significance to the survival and reproduction of any individual because it determines individual fitness. Strategies are shaped by diverse factors: temperature, precipitation, and nest predation risks may be some of them. From a four-year study, we analyzed the role of temperature, precipitation, and nest predation risk in relation to change in the life history strategy of the Varied Tit (<em>Sittiparus varius</em>). Specifically, clutch size was negatively related to both ambient temperature and nest predation risk. The reproductive success rate was negatively related to both temperature and precipitation, but only when the predation risk was low. First-egg laying date was not significantly related to any recorded factors. These results help us better understand the evolution of life history and inform us regarding management decisions for wild population conservation.

Effect of sympatry on discrimination of heterospecific song by varied tits

Many animals recognize their own species through acoustic signals, and erroneous recognition incurs costs. Birds discriminate between conspecific and heterospecific songs; for example, male territory owners respond aggressively to songs of conspecific males within their territories, but not to heterospecific songs. This discrimination is affected by the costs associated with territory defence behaviours. In populations where birds live with a related species that sings similar songs, males may waste time and energy on useless territory defence behaviours if they mistakenly recognize heterospecific songs as conspecific ones. On the other hand, if males in allopatric populations recognize conspecific songs as heterospecific songs, they may risk losing territories because the songs are sung by conspecific rivals in the absence of heterospecifics. For this reason, the potential costs of erroneous species recognition are expected to differ between sympatric and allopatric populations. Thus, it can be hypothesized that, in species without interspecific territoriality, males in sympatry respond less strongly or not at all to heterospecific songs similar to their own, and males in allopatry respond equally to heterospecific and conspecific songs. In this study, I examined this hypothesis using varied tits, Poecile varius , in the Ryukyu Archipelago, Japan. Their songs are similar in structure to those of confamilial Japanese tits, Parus minor . I used song playbacks and evaluated the aggressive responses of 355 territorial males in seven populations of varied tits. Overall, varied tit males responded strongly to conspecific songs but only weakly to Japanese tit songs. Furthermore, responses to the heterospecific songs were much weaker in the sympatric populations than in the allopatric ones, which is consistent with the hypothesis tested. This study suggests that when secondary contact occurs, song discrimination may influence the effectiveness of territorial behaviours and the reproductive success of individual males from sympatric and allopatric populations. • I studied the effect of closely related species on song discrimination in birds. • I used playbacks of conspecific and heterospecific songs and compared the responses. • Male responses were weaker to heterospecific songs than to conspecific songs. • This effect was greater in sympatric populations than in allopatric populations. • Coexistence of related species may influence discrimination of conspecific song.

Loss of Extra-pair Paternity is not Associated with Decreased Paternal Investment in Mixed-paternity Broods or Unrelated Nestlings in the Varied Tit, Parus varius

Males of socially monogamous bird species may be faced with providing costly care for unrelated offspring when nests have extra-pair young (EPY). Theoretical models predict that cuckolded males should lower their parental investment as the likelihood of paternity decreases. However, empirical data are not always in support of this prediction. Here, we explore parental behaviours within the context of extra-pair patenity (EPP) in a population of the varied tit Parus varius in China. The results showed that 39.5% of nests were cuckolded and 16.4% of chicks were sired by extra-pair males. We found no evidence that male and female varied tits reduced their feeding rates or relative feeding effort to EPP broods, or that they decreased provisioning for EPY in mixed broods. There was also no direct effect of EPP on the reproductive success of breeding adults and the body condition nestlings near fledging. The lack of reliable cues of EP copulations (EPC)s by social mates available for the males, and/or the absence of strictly environmental pressure on males that would favor discrimination may account for a lack of an adjustment in feeding effort. The absence of discrimination between own and EPP chicks in parental care suggests that females pay no fitness cost as a result of EPCs, which may explain the high frequency of EPY in nests.

Spatio-temporal variation in egg-laying dates of nestbox-breeding varied tits (Poecile varius) in response to spring pre-breeding period temperatures at long-term study sites in South Korea and Japan

ABSTRACT Climate change can alter and disrupt the phenology and phenological interaction between organisms from various trophic levels in forest ecosystems. In temperate forests, the breeding phenology of birds is correlated to local microclimate, especially spring temperature to match the timing of food availability. Recent studies revealed that the temperature warming is more pronounced in high-elevation areas (elevation-dependent warming), while the breeding phenology shift of birds in this condition needs further investigation. We studied the annual change in the egg-laying dates of varied tits (Poecile varius) and a pre-breeding temperature index in three plots located along with the elevational gradient in South Korea and a low-elevation plot in Japan. We found strong support for disproportionate rates of changes in higher elevation for warming trends in pre-breeding period and advances in egg-laying dates over the last decade. Next, we compared three segments of 36-year data from Akazu Research Forest. The evidence from pre-breeding temperature during 36 years indicates that we could detect the change in thermal environment and breeding phenology with longer years of data, especially in lower elevation regions. This result shows the need for long-term research to understand the change in local temperatures and the ecology of forest birds. Our study presents evidence of elevation-dependent phenological advance in avian breeding activities and discusses the need for systematic long-term research on multiple taxa and climatic drivers in Asia.

Predicting climate-driven shifts in the breeding phenology of Varied Tits (Sittiparus various) in South Korean forests

ABSTRACT Phenological shifts of plants and animals due to climate change can vary among regions and species, requiring study of local ecosystems to understand specific impacts. The reproductive timing of insectivorous songbirds in temperate forests is tightly synchronized with peak prey abundance, and thus they can be susceptible to such shift in timing. We aimed to investigate the effect of future climate change on the egg-laying phenology of the Varied Tit (Sittiparus various), which is common and widely distributed in South Korean forests. We developed the predictive model by investigating their egg-laying dates in response to spring temperatures along geographical gradients, and our model indicated that the tits lay eggs earlier when the average of daily mean and daily maximum temperatures rise. We predicted future shifts in egg-laying dates based on the most recent climate change model published by the Intergovernmental Panel on Climate Change (IPCC), under a scenario with no climate change mitigation and under a scenario with moderate mitigation. Under this outcome, this species might be unable to adapt to rapid climate change due to asynchrony with prey species during the reproductive period. If no mitigation is undertaken, our model predicts that egg-laying dates will be advanced by more than 10 days compared to the present in 83.58% of South Korea. However, even moderate mitigation will arrest this phenomenon and maintain present egg-laying dates. These results demonstrate the first quantitative assessment for the effect of warming temperatures on the phenological response of insectivorous songbirds in South Korea.

An improved automatic trap for capturing birds in nest boxes

Several traps have been designed for capturing birds in their nest boxes, and questions remain concerning the effectiveness, reliability and automatism of the traps. Here we developed an automatic trap, designed to capture parent birds in artificial nest boxes. When a bird enters the nest box, the trap will be triggered by pulling on a twig treadle and the door will shut securely with a magnet. During 2014–2016, the trap was used to capture Varied tits (Parus varius), Marsh tits (Parus palustris) and Great tits (Parus major) during the breeding seasons. We captured 177 birds, with a trigger rate of 92.2%, a capture rate of 100% and an average capture time of 22.5 ± 19.6 min. No known trap-related injuries or desertions occurred. This light weight, easily operated, and highly efficient trap improves the data collection and results during field work. This trap can be used in a wide variety of nest boxes to capture songbirds.

杂色山雀双亲差异性育雏策略

杂色山雀双亲差异性育雏策略

Highly toxic seeds of the Japanese star anise Illicium anisatum are dispersed by a seed‐caching bird and a rodent

AbstractMany field studies on plant seed dispersal teach us that we cannot judge the effective dispersal mode of plants by examining only the morphologies of the fruits and seeds. In the present study, we explored the seed dispersal process of an evergreen tree, the Japanese star anise Illicium anisatum, which is highly toxic, containing neurotoxins in both the fruits and seeds. The fruits exhibit ballochory, a mode of seed dispersal characterized by explosive fruit dehiscence, and the extreme toxicity apparently seems to deter fruit and seed consumption by animals. However, we found that the dispersal distance afforded by this mode was very short (≤ 6 m). In the field, we confirmed that a passerine species, the varied tit Poecile varius, was the only consumer of the seed in foliage, and the bird actively transported seeds or fruits to either cache or consume them. Seeds setting on the forest understory were removed by the small Japanese field mouse Apodemus argenteus, and were also dispersed by this animal. Analysis of seedling spatial distribution revealed that seedlings were highly aggregated near standing trees or fallen logs, suggesting that caching facilitated seed dispersal. This study warns that plant toxicity and the ecological function thereof should not be evaluated based only on limited knowledge of the effects on humans and mammals. Our results pose further questions on the evolution of toxin tolerance in seed‐caching animals and on the mutualism between toxic plants and animals.

Home-range Analysis of Varied Tit(Parus varius) in the Post Fledging Period by Using Radio-tracking

Home-range Analysis of Varied Tit(Parus varius) in the Post Fledging Period by Using Radio-tracking

Song learning in Varied Tits Poecile varia: sensitive period and the effects of night-sleep

ABSTRACTCapsule: Varied Tits Poecile varia learned vocalizations in the first few weeks of their life. Night-sleep affected the development of vocal learning in Varied Tits.Aims: We aimed to quantify the sensitive period of song learning and to examine the effects of sleep on song development in Varied Tits, an endemic forest songbird in East Asia.Methods: Song development in Varied Tits was investigated in the first 90 days following hatching. The effect of night-sleep on birdsong learning was examined by analysing and comparing the song structure in the evening and the next morning.Results: We found that most individuals began to sing a subsong from 15 days of age and acquired mature song at about 53 days. The sensitive period of song learning in Varied Tits was from 25 to 53 days after hatching. There were significant and positive correlations between maximum frequency and vocal changes before and after night-sleep.Conclusion: Our findings uncover the timings and processes of song development, and highlight the importance of the sensitive period in birdsong development in wild birds.

Small patches of broadleaf trees influence nest-site selection and reproductive performance of two tit species (Paridae) in a Japanese cedar plantation

ABSTRACTConifer plantations generally provide less food for woodland birds such as tit species than do broadleaf or mixed forests. We examined whether small patches of broadleaf (thus, caterpillar-rich) trees in a Japanese cedar (Cryptomeria japonica) plantation could improve the breeding success of coal tits (Periparus ater) and varied tits (Poecile varius) using nest boxes in the plantation. We evaluated the relationships between the distribution of the broadleaf trees (the minimum distance from each nest box to the nearest patch and the total area of broadleaf patches within 25, 50, 100, and 200 m from each nest box) and breeding performance (clutch size, number, and body mass of fledglings, fledging success, fledge rate, and nestling period). Coal tits selected nest boxes regardless of the distribution of broadleaf patches. By contrast, varied tits nested preferentially within 50 m of broadleaf patches and, within 50 m, favored boxes near a larger total area of broadleaf patches than coal tits. The breeding performance of both species was not affected by the distribution of patches; however, the clutch size of varied tits (but not coal tits) tended to decline in nests ≥50 m from broadleaf patches, and there were no large clutches in such positions. The broadleaf trees might have improved the habitat quality, particularly for varied tits, by providing food resources. Thus, broadleaf patches as foraging sites and nest boxes as breeding sites could both be critical to the breeding success of woodland birds in conifer plantations.

Asymmetric response to song dialects among bird populations: the effect of sympatric related species

Given that birds discriminate heterospecific songs from conspecific ones, bird songs have a function in species recognition. Even in the same species, local populations often have somewhat different songs (i.e. dialects). Birds might discriminate nonlocal dialects from local dialects due to the differences in acoustic characteristics between them. Discrimination of nonlocal dialects from individuals' own dialects has the potential to promote reproductive isolation. Individuals in populations with sympatric related species that sing similar songs might discriminate not only heterospecific songs but also the nonlocal dialects of conspecifics. In populations without sympatric related species, individuals may not need to distinguish local conspecific songs from similar types of songs and may not discriminate nonlocal dialects from their own dialect. I investigated this hypothesis using Japanese tits, Parus minor, and varied tits, Poecile varius, in the Ryukyu Archipelago, Japan. I performed playback experiments to simulate territorial intrusions by forming pairs of two populations: one lived with, and the other without, the related tit species. The results from two and three paired populations of Japanese and varied tits, respectively, showed that males living with other sympatric species responded strongly to their own dialects but weakly to foreign dialects of conspecifics. Additionally, males living without a related species did not respond differently to the dialects. This asymmetric response pattern indicates that sympatric related species have important effects on response to conspecific song dialects, which may have implications for gene flow and reproductive isolation among populations with differing dialects.

A review of the subfamily Picobiinae Johnston and Kethley, 1973 (Acariformes: Prostigmata: Syringophilidae).

The fauna of quill mites of the subfamily Picobiinae Johnston and Kethley, 1973 (Acariformes: Cheyletoidea: Syringophilidae) is comprehensively revised. All of 78 known species, which are grouped into 11 genera, are examined and diagnosed or redescribed. Data on picobiine hosts and distribution are summarized, including new host and locality records. The following new species are described: Charadriineopicobia apricaria sp. nov. ex Pluvialis apricaria (Linnaeus) (Charadriiformes: Charadriidae) from France, Neopicobia pari sp. nov. ex Periparus venustulus Swinhoe (type host) (Passeriformes: Paridae) from China, Parus major Linnaeus (Paridae) from Macedonia and Finland, and Poecile varius Temminck and Schlegel (Paridae) from Japan, Picobia magellani sp. nov. ex Scytalopus magellanicus (Gmelin) (Passeriformes: Rhinocryptidae) from Colombia, Picobia lonchura sp. nov. ex Lonchura leucogastra (Blyth) (Passeriformes: Estrildidae) from Indonesia, Picobia makoli sp. nov. ex Xiphocolaptes promeropirhynchus (Lesson) (Passeriformes: Furnariidae) from Colombia. The species Picobia polonica Skoracki, Magowski and Dabert, 2001 syn. nov. is a junior synonym of C. khulkhaskhani Kivganov and Sharafat, 1995. The following new combinations are proposed: Neopicobia ictericus (Skoracki and Glowska, 2010) comb. nov., Rafapicobia brotogeris (Fain, Bochkov and Mironov, 2000) comb. nov., and Rafapicobia ramphastos (Fain, Bochkov and Mironov, 2000) comb. nov. Keys to the all picobiine genera and species are presented, along with a check-list of picobiine species and their hosts.

The Relationships between Prey Size, Nestling Age, Provisioning Rate, and Elevation in the Varied TitParus varius

Abstract To determine the major factor of change in provisioning rates to Varied Tit Parus varius nestlings in relation to increasing elevation, we used video recordings to investigate the number of parent visits and the size of prey carried by parents to their nestlings during the breeding process. Video cameras were installed at the entrances of 35 nests (17 at 300 m a.s.l., 7 at 900 m a.s.l., and 11 at 1,400 m a.s.l.). We also measured air temperature during the breeding season at three study sites. The provisioning rates per nestling showed a significantly negative relationship with prey size provisioned, except during the early nestling stage (days 1 to 4), when small prey were selectively provisioned by the parents. Prey at the higher elevation during days 5 to 15, also, were significantly smaller than at the lower elevation. The mean temperature at each breeding site during the breeding period did not differ significantly due to the delayed onset of breeding at higher elevation. Therefore, we concl...

Geographic variation in bird songs: examination of the effects of sympatric related species on the acoustic structure of songs

Birdsong evolution has influenced by various ecological and social factors. When related species that sing similar songs coexist, the acoustic properties of the songs of one or both species may shift, and the songs may diverge. We investigated geographic variation in the songs of the Japanese tit (Parus minor) and the varied tit (Poecile varius) in the Ryukyu Archipelago, Japan, whose islands harbor either one or both species. The songs of the two species exhibited similar structure, but acoustic measurements differed between them. For example, varied tits sang songs at higher frequency than Japanese tits did. The songs of both species varied geographically. At sites with higher relative densities of varied tits, Japanese tits sang lower frequency songs, indicating that in areas of coexistence, Japanese tits sang songs that had acoustically diverged from those of varied tits. Song variation in varied tits was not related to sympatry with Japanese tits. These asymmetric results suggest that the subordinate Japanese tit modified the acoustic characteristics of its song to avoid harassment by the dominant varied tit. We observed no effects of genetic divergence or local intraspecific density on Japanese tit or varied tit songs. This study used geographic variation to examine hypotheses of song evolution, and the results highlight the importance of character displacement.

History of bird-keeping and the teaching of tricks using Cyanistes varius (varied tit) in Japan

The keeping of pet birds in Japan is reviewed with emphasis on Cyanistes varius (varied tit). Traditionally, bird-keeping in Japan was mainly for the enjoyment of their songs. Songbird competitions were popular and training of birds to sing was common, especially in the Edo Era from the seventeenth to the nineteenth centuries, which meant that it was known that birds learn to sing and have dialects in their songs. There were districts famous for producing birds with beautiful voices. Within the bird-keeping culture of Japan, the varied tit had a specific image, which was different from other birds. They were trained to perform tricks and were used in street performances from the Edo Era until the middle of the twentieth century, when the tradition disappeared. The decline of the bird-keeping culture and the training of tricks may benefit the conservation of wild birds, but it also marks the loss of an ancient cultural tradition in Japan.

杂色山雀的婚外父权与配偶间的遗传相容性无关

杂色山雀的婚外父权与配偶间的遗传相容性无关

食物和季节因素对杂色山雀贮食行为影响的研究

食物和季节因素对杂色山雀贮食行为影响的研究