Reed Bunting Emberiza Schoeniclus Research Articles

Territory settlement and site fidelity in Reed Buntings Emberiza schoeniclus

Capsule Site fidelity and territory settlement is probably limited by the occupancy of suitable sites by males and the high mortality in females. Aim To investigate the relationship between territory settlement and site fidelity in Reed Buntings. Methods Two hundred and seventy Reed Buntings were colour‐ringed at five fishponds in South Bohemia, the Czech Republic, in 2000–2009. Model selection was used to test the effect of individual covariates (sex, age, weight and body measurements) on apparent survival and recapture probabilities. Results There is a correlation between territory settlement and site fidelity. Older males were more frequently re‐sighted in the study area during the year of ringing. Moreover, males were more frequently recovered in subsequent breeding seasons. An effect of body measurements as well as body weight did not appear evident. An effect of breeding performance in previous seasons on site fidelity was not found. Conclusion There is a connection between territory settlement and site fidelity in the early‐arriving Reed Buntings. Site fidelity and territory settlement is probably limited by the occupancy of suitable sites by males and the high mortality in females most likely caused by the extended breeding season in the study area. Moreover, territory settlement, and marginally, site fidelity is associated with the previous experience of males. Forming pre‐breeding flocks probably provides an addition of nutrition reserves after spring arrival. High competition between males and lack of suitable breeding habitats, owing to occupancy by older residents, indicated the crucial importance of small fragmented wetlands to this species in this study area.

Endangered subspecies of the Reed Bunting (Emberiza schoeniclus witherbyi and E. s. lusitanica) in Iberian Peninsula have different genetic structures

In the Iberian Peninsula, populations of two subspecies of the Reed Bunting Emberiza schoeniclus have become increasingly fragmented during the last decades when suitable habitats have been lost and/or the populations have gone extinct. Presently, both subspecies are endangered. We estimated the amount of genetic variation and population structure in order to define conservation units and management practices for these populations. We found that the subspecies lusitanica has clearly reduced genetic variation in nuclear and mitochondrial markers, has a drastically small effective population size and no genetic differentiation between populations. In contrast, the subspecies witherbyi is significantly structured, but the populations still hold large amounts of variation even though the effective population sizes are smaller than in the non-endangered subspecies schoeniclus. We suggest several management units for the Iberian populations. One unit includes subspecies lusitanica as a whole; the other three units are based on genetically differentiated populations of witherbyi. The most important genetic conservation measure in the case of lusitanica is to preserve the remaining habitats in order to at least maintain the present levels of gene flow. In the case of the three management units within witherbyi, the most urgent conservation measure is to improve the habitat quality to increase the population sizes.

Variation in singing style use in the reed bunting Emberiza schoeniclus: influencing factors and possible functions

The two main functions of bird song are territory defence and mate attraction. Considerable progress has been made in understanding how species adjust the use of songs to serve these and other (presumed) functions of bird song, but the striking variety of singing behavior observable in wild birds remains enigmatic. Some species make do with simple songs and small repertoires, while others show large, complex repertoires and still others have evolved several distinct singing styles. In most species with distinct singing styles, however, the functions of singing styles are poorly understood. Two distinct singing styles (type I and II, respectively) have long been known in the reed bunting Emberiza schoeniclus, while a new third one has recently been reported to exist. We first quantitatively investigated the evidence for the existence of three singing styles. Then, we tested predictions of the mate attraction hypothesis, the mate guarding hypothesis and the territory defence hypothesis by examining the relations between singing style use with social and temporal factors. Cluster and discriminant analyses supported the existence of three (instead of two) singing styles, which could be differentiated based on four variables referring to song structure and complexity. Use of singing styles was related to male mating status (consistent with the mate attraction hypothesis), but not to female breeding stage (no support for the mate guarding hypothesis). Finally, use of singing styles differed in relation to time of day, with the dawn chorus of paired reed buntings consisting almost exclusively of songs of the recently discovered type III singing style and daytime singing primarily consisting of songs of long‐known type I (in unpaired males) or II singing styles (in paired males). Our findings suggest that one singing style (type I) primarily serves to attract a social mate, although an additional territorial function of this singing style cannot be dismissed. The function(s) of the other two singing styles, both only sung by paired males, are not related to attraction of a social mate or to the own female's fertility, but appear to be important in the context of territory defence and extra‐pair matings.

The environmental impacts of biomass crops: use by birds of miscanthus in summer and winter in southwestern England

We compared birds in a group of established and well‐managed miscanthus (Miscanthus x giganteus) fields in Somerset and East Devon, southwestern England, with plots of short rotation coppice (SRC) willow, arable crops and grassland in two winters and one summer. Following early spring cutting, 19 miscanthus fields grew taller, initially produced greater cover and were less weedy than SRC. As stubble in May, the miscanthus contained broadly similar species at similar densities to arable and grassland comparison plots. By July, at 2‐m‐tall, miscanthus held higher densities of birds but of fewer species, most of them characteristic of woodland and scrub. SRC, previously identified as being a beneficial crop for many birds, always contained more species and individuals than miscanthus. Throughout each of two winters, 15 miscanthus plots remained unharvested and contained more wood/scrub species such as Blackbirds Turdus merula, tits, Reed Buntings Emberiza schoeniclus and Woodcock Scolopax rusticola than the comparison plots, which held more corvids and Skylarks Alauda arvensis amongst others. Similar overall mean densities of birds in the miscanthus and the comparison plots masked relatively low density variance in miscanthus and very high variance in the comparison plots. Unharvested miscanthus crops grown in place of habitat types supporting flocks of wintering birds would displace these flocks. Miscanthus plantations with open patches attracted more finches and waders in winter. The two previous studies of birds in miscanthus in the UK found more species and more individuals than we did in summer and winter. Both these studies documented high levels of weediness and patchy crop growth. In the context of this previous work our data suggest that bird use of miscanthus in summer and winter is likely to be variable, affected by region, weediness, crop structure and patchiness. While large‐scale cropping of SRC in England is likely to have a positive overall impact on a suite of common farmland and woodland birds, our data suggest that miscanthus in the southwest of England may have an approximately neutral effect. However, some open farmland specialist species may be lost when planting either crop.

Bird ringing in Britain and Ireland in 2009

This is the 73rd annual report of the British Trust for Ornithology's Ringing Scheme, covering data received and work carried out in 2009. Much of the research carried out during the year looked at ways to improve the analysis of ringing data to understand population change. This included producing survival rates from the Constant Effort Sites (CES) scheme for the first time and further developing methods of analysing our demographic data sets in an integrated manner. Research was also undertaken on the biometric data to investigate how individual condition responds to long‐term environmental change. CES data suggested that the low productivity in 2007 and 2008, combined with one of the coldest winters since 1995/96 for residents, contributed to reduced adult numbers in 2009 in many species. There were significant decreases in Wren Troglodytes troglodytes, Sedge Warbler Acrocephalus schoenobaenus, Reed Warbler A. scirpaceus, Blackcap Sylvia atricapilla, Lesser Whitethroat S. curruca, Willow Warbler Phylloscopus trochilus, Long‐tailed Tit Aegithalos caudatus, Blue Tit Cyanistes caeruleus, Great Tit Parus major, Treecreeper Certhia familiaris, Chaffinch Fringilla coelebs, Greenfinch Carduelis chloris and Reed Bunting Emberiza schoeniclus. However, a good breeding season, for both residents and migrants, resulted in significantly higher productivity for 15 species, but significantly lower for Willow Tit Poecile montana, compared to the long‐term mean (1983–2007). Data for 104 Retrapping Adults for Survival studies were submitted, covering 39 species, three quarters of which are Birds of Conservation Concern. The total number of birds ringed (935,867) was the highest ever recorded, and was over 10% higher than the mean of the previous five years. However, the total number of pulli ringed in 2009 (179,712) was only 5% higher than the preceding five‐year mean, while that of fully grown birds (756,155) was over 13% higher. The recovery total (14,643) was also high. However, this is partly due to changes in the way that records of colour‐ringed and other specially marked birds are stored. The number of recoveries of foreign‐ringed birds (1,314) was higher than the mean of the preceding five years, although this figure is influenced by varying response times of different ringing schemes. Recovery details for 250 individual birds are given in the final section of the report. They include movements that confirm suspected or known migration patterns, unexpected movements and longevity records.

Lowland Farmland Birds III: Delivering Solutions in an Uncertain World. A report on the BOU’s Annual Conference held at the University of Leicester, 31 March–2 April 2009

Lowland Farmland Birds III: Delivering Solutions in an Uncertain World. A report on the BOU’s Annual Conference held at the University of Leicester, 31 March–2 April 2009

Morphological sexing of passerines: not valid over larger geographical scales

Sex determination of birds is important for many ecological studies but is often difficult in species with monomorphic plumage. Morphology often provides a possibility for sex determination, but the characters need to be verified. We tested whether five passerine species can be sexed according to standard morphological measurements applying a forward logistic regression with sex determined by molecular analysis as the dependent variable. Furthermore, we tested whether the results can be used on a larger geographic scale by applying morphological sexing methods gained by similar studies from other regions to our data set. Of the five species of this study only Garden Warblers Sylvia borin could not be sexed morphologically. In the Robin Erithacus rubecula, 87.2% of all individuals were sexed correctly. For Reed Warblers Acrocephalus scirpaceus, Willow Warblers Phylloscopus trochilus and Reed Buntings Emberiza schoeniclus, the respective values were 77.6, 89.4 and 86.4%. When the logistic regression functions from similar studies on Robins and Reed Buntings in Denmark and Scotland were applied to the birds from south-western Germany, they performed less well compared to the original dataset of these studies and compared to the logistic regression function of our own study. The same was the case for Willow Warblers when a wing length criterion used in Great Britain was applied to the birds of our study. These discrepancies may have several explanations: (1) the models are optimised for the dataset from which they were extracted, (2) inter-ringer variation in measurements, (3) the use of different age cohorts, (4) different morphology due to different habitat availability around the study site, or, most likely, (5) different morphology due to different migratory behaviour. We recommend that morphological sex differentiation methods similar to this study (1) be only used population specific, (2) only with one age cohort and (3) to adjust the extracted equations from time to time.

Small and large wetland fragments are equally suited breeding sites for a ground-nesting passerine

Large habitat fragments are generally thought to host more species and to offer more diverse and/or better quality habitats than small fragments. However, the importance of small fragments for population dynamics in general and for reproductive performance in particular is highly controversial. Using an information-theoretic approach, we examined reproductive performance and probability of local recruitment of color-banded reed buntings Emberiza schoeniclus in relation to the size of 18 wetland fragments in northeastern Switzerland over 4 years. We also investigated if reproductive performance and recruitment probability were density-dependent. None of the four measures of reproductive performance (laying date, nest failure probability, fledgling production per territory, fledgling condition) nor recruitment probability were found to be related to wetland fragment size. In terms of fledgling production, however, fragment size interacted with year, indicating that small fragments were better reproductive grounds in some years than large fragments. Reproductive performance and recruitment probability were not density-dependent. Our results suggest that small fragments are equally suited as breeding grounds for the reed bunting as large fragments and should therefore be managed to provide a habitat for this and other specialists occurring in the same habitat. Moreover, large fragments may represent sinks in specific years because a substantial percentage of all breeding pairs in our study area breed in large fragments, and reproductive failure in these fragments due to the regularly occurring floods may have a much stronger impact on regional population dynamics than comparable events in small fragments.

Nest predation in Reed Buntings Emberiza schoeniclus: an experimental study

Predation is a major cause of nest failure in many bird species. High levels of nest loss may be a consequence of habitat fragmentation, leading to increased amounts of edge habitat. Yet the evidence for generally high nest predation rates along edges in fragmented landscapes is ambiguous. Using real nests of Reed Buntings Emberiza schoeniclus in which artificial Reed Bunting and real Japanese Quail Coturnix japonica eggs were placed, we experimentally tested for edge effects on nest predation in highly fragmented reed Phragmites sp. habitats in the Swiss lowlands. We also examined seasonal patterns of predation and the impacts of nest visits by observers. We found evidence for an edge effect at the water‐sided reed edge, with nests located closer to the water being more likely to be predated than those further away. Predation probability increased from early to late season, suggesting that nest predation may be density dependent. Probability of nest predation was only weakly influenced by whether or not a nest was visited. Our results suggest that the intensive reed management currently applied in Swiss nature reserves may result in unnaturally high levels of nest losses in the Reed Bunting, because reed bands are not wide enough to allow nest placement at a safe distance from reed edges.

Winter diet of reed bunting Emberiza schoeniclus in fallow and stubble fields

An analysis of droppings collected in winter on unused fields in SW Poland (fallow, stubble of root crop, vegetable and cereal) showed that the base of the reed bunting Emberiza schoeniclus diet were seeds of annual weed species: Chenopodium album (74.06% of all recorded seed species), Amaranthus retroflexus (16.05%), Setaria viridis (9.50%), Stellaria media (0.21%), Fumaria officinalis (0.01%). The share of dominant weed species in the diet of reed bunting wintering on particular types of fields varied markedly. In the droppings from fallows and cereal stubbles, C. album clearly dominated (respectively, 88.60 and 66.12%). The highest proportion of A. retroflexus and S. viridis was detected in the diet of birds staying on root crop stubbles (respectively, 45.56 and 23.90%). The most diverse food composition was found in the case of birds feeding on root crops and the least diverse on fallows.

Weather conditions affect levels of extra‐pair paternity in the reed buntingEmberiza schoeniclus

Extra‐pair paternity (EPP) is common in many socially monogamous birds, but large variations in frequency of EPP are found both between and within species. Local ecological factors can affect the costs and benefits of extra‐pair mating behaviour, and may therefore influence the chance that individuals engage in extra‐pair copulations (EPCs). We investigated the effect of weather conditions during the peak fertile period of the female on the levels of EPP in reed buntingsEmberiza schoeniclus. The reed bunting is a socially monogamous passerine, with extremely high levels of EPP (50% of offspring in 80% of broods). We found that higher daily minimum temperatures and more rainfall during the peak fertile period were associated with lower proportions of EPP. As during adverse weather conditions individuals have to invest more in self maintenance, we suggest that during long periods of rain the extra‐pair mating behaviour of all individuals will be restricted, leading to lower proportions of EPP. During cold mornings, time‐consuming activities such as mate guarding are likely to be more strongly affected than less time‐consuming activities such as EPCs, leading to higher proportions of EPP.

Summer utilization of Oilseed Rape by Reed Buntings Emberiza schoeniclus and other farmland birds

Capsule Oilseed Rape was the preferred breeding season habitat for Reed Buntings on arable farmland and reduced this species' dependence on wet features. Aims To identify preferred breeding season habitats for Reed Buntings on arable farmland and factors influencing the attractiveness of Oilseed Rape. Methods Summer usage of arable fields by nesting and foraging farmland birds was assessed from a random sample of arable fields in Nottinghamshire, England. Generalized linear models were used to identify habitat and landscape predictors of Reed Bunting breeding density and of foraging by other farmland birds. Results Occupancy rates and densities of Reed Buntings were approximately four times greater in Oilseed Rape fields than in cereals or set-aside. Reed Buntings commonly nested in Oilseed Rape fields more than 100 m from wet features, but the same was not true of cereals or set-aside fields. Usage of Oilseed Rape by farmland birds was promoted by weediness, bare patches and nearby wet features, and reduced by grass margins, tall field boundaries and electricity pylons. Conclusions Oilseed Rape is one of the most important breeding season habitats for Reed Buntings in lowland Britain, providing a relatively rich source of seed and invertebrate food and possibly protection from nest predators. Breeding in Oilseed Rape reduces the dependence of Reed Buntings on nearby wet features.

Autumn migration of Reed Buntings Emberiza schoeniclus in Switzerland

To elucidate the migration strategies of Reed Buntings Emberiza schoeniclus migrating through Central Europe, we analysed data from 595 Reed Buntings ringed at La Touvière, Rhône River, Geneva, Switzerland, during the autumn migration from September to November 2004. These data were used to investigate age, sex, biometrics and body condition in relation to timing of migration. The overall sex ratio and the ratio of first‐years to adult birds were 1:1 and 3:1, respectively, but there was a chronological sequence of young females, adult females, young males and adult males during the autumn. The mean bill depth varied during the study period with individuals migrating during October having deeper bills. The greater bill depth of males by comparison with other European studies suggests a more northeasterly origin of these birds, compatible with a leap‐frog migration.

Old female reed buntings (Emberiza schoeniclus) increase extra-pair paternity in their broods when mated to young males

AbstractIn birds, females are generally assumed to determine whether extra-pair copulations occur, and thus most studies on extra-pair paternity (EPP) have focussed on female preference for male traits, whereas female traits have been largely neglected. However, the occurrence of EPP is likely to be a result of behavioural interactions (e.g., mate guarding by the social male and escaping mate guarding by the female), and may be related to individual experience, which is expected to increase with age. We investigated the effect of age on levels of EPP in reed buntings Emberiza schoeniclus, a socially monogamous passerine with extremely high levels of extra-pair young (more than 50% of offspring). In broods of older males the rate of cuckoldry declined, which is in agreement with our previous finding that older males are more successful, either through female choice or through male experience. In contrast, older females tended to increase the level of extra-pair paternity in their broods. When including the age of the partner, we found that young males, but not old males, were cuckolded more by old females than by young females. The increase in EPP with female age is not likely to be due to disassortative mating with respect to age, an increased capacity of older females to raise a brood without male help, nor a male preference for older females. With age, males nor females changed their share in parental effort. We suggest that with increase in age, females become more choosy when selecting the male that sires their offspring, or alternatively, become more experienced at circumventing paternity assurance tactics of young males.

Numerical and functional responses of breeding passerine species to mass occurrence of geometrid caterpillars in a subalpine birch forest: a 30‐year study

In northern Fennoscandia, the geometrid moths Epirrita autumnata and Operophtera brumata have cyclicities in density with mass occurrence at 10‐year intervals. The larvae of Epirrita and Operophtera attain a size of 2–3 cm and 1.5–2 cm, respectively, and are nutritious food items for passerine birds. To examine whether these larvae have any numerical and/or functional influence on a passerine bird community (mountain birch forest in Budal, central Norway) during a 30‐year period (1972–2001), I estimated their abundance (number of larvae per 100 sweeps) in the birch canopy, and the densities of breeding birds in the passerine community. In addition, from 1972 to 1998, I monitored the nesting success of five of the bird species. The foraging pattern of the most abundant bird species and their gizzard contents (adults and nestlings) were examined in 1972–78 (covering population peaks of both the geometrids). Population peaks of Epirrita occurred in 1975–76, 1985–86 and 1996, and of Operophtera in 1976–77, 1986–87 and 1997–98. The passerine community consisted of eight species that were territorial in all 30 years, one species in 26 years, three species in 14–21 years and three species in 1–4 years. Only the Brambling Fringilla montifringilla population responded numerically to the fluctuations of Epirrita and Operophtera. Brambling was also the only species whose mean clutch size varied between years, and this correlated positively with the density of Epirrita. The mean annual nesting success of Willow Warbler Phylloscopus trochilus, Bluethroat Luscinia svecica and Common Redpoll Carduelis flammea tended to be higher in years with mass outbreaks of Epirrita, but was significantly so only for Reed Bunting Emberiza schoeniclus. The abundance of Operophtera larvae showed no influence on the nesting success of any bird species. The passerines foraged more frequently in the birch canopy in the Epirrita outbreak years (1975–76) than in the years before or after. Gizzard analyses of five adult passerine species and their nestlings showed that Epirrita was the main food item in 1974–76. Even though Operophtera occurred in large numbers in birch trees in 1976 and 1977, only a few larvae were found in the gizzards of the passerines. None of the passerines showed an increase in their population density in the year following the larval outbreaks, but the densities of Willow Warbler and Bluethroat increased in the succeeding year, indicating a higher return rate for these species. The study shows the existence of a dietary response and also indicates a reproductive response to the changes in the abundance of Epirrita in mountain birch forest. The lack of numerical response in the passerines (except the Brambling) to the fluctuation in Epirrita contrasts with the pattern described for passerine communities in northern temperate deciduous forests in North America, where Lepidoptera caterpillars periodically have mass outbreaks.

Effects of habitat on the use of supplementary food by farmland birds in winter

Providing supplementary food for seed‐eating birds in winter is likely to be a key strategy, in some form, in future efforts to conserve farmland biodiversity. We present interim analyses of data on the bird use of artificial feeding sites under the RSPB‐led BirdAid project and the BTO‐led Winter Food for Birds (WFFB) project, investigating the influence of the habitat context at the local and landscape scales on the use of supplementary food by Yellowhammer Emberiza citrinella, Corn Bunting Miliaria calandra, Tree Sparrow Passer montanus, House Sparrow Passer domesticus, Chaffinch, Fringilla coelebs, Greenfinch Carduelis chloris, Goldfinch C. carduelis and Reed Bunting Emberiza schoeniclus. Our results reveal species‐specificity, rather than general patterns, in relationships between habitat variables and counts. The responses of the only species for which both BirdAid and WFFB provided data, the Yellowhammer, differed between the projects, suggesting that the results were not geographically general. The results fail to indicate justifiable firm habitat prescriptions for site locations that would suit a number of species. Clearer patterns were apparent in results with respect to areas of major habitats in the landscapes surrounding feeding sites, which suggested that local abundance could have an important effect on the use of supplementary food. Future analyses of data from these projects will attempt to separate the competing probable habitat influences on local bird abundance and alternative resource availability.

The breeding ecology of Reed Buntings Emberiza schoeniclus in farmland and wetland habitats in lowland England

We studied the nesting and feeding ecology of Reed Buntings Emberiza schoeniclus breeding on farmland and wetland habitats along the Trent Valley in Nottinghamshire, England. Rank and emergent vegetation accounted for most nests and most foraging by provisioning adults. Caterpillars and spiders accounted for 70% of chick invertebrate prey and all broods were fed cereal grain or other vegetable matter. Variation in the abundance of key invertebrate prey across habitats accounted for the foraging preferences of adult buntings. Depredation was the main cause of nest failure, and survival of nests at the egg stage was positively related to the extent of nest concealment. A measure of total brood biomass was positively related to the abundance of key invertebrate prey within 100 m of nests. Rank and emergent vegetation provided Reed Buntings with greater nest concealment and a richer source of invertebrate prey than agricultural habitats such as set‐aside, cereals and oilseed rape. The provision of rank and emergent vegetation on farmland is likely to increase the nesting opportunities and productivity of Reed Buntings in agricultural landscapes.

Area Requirements Of Passerine Birds In The Reed Archipelago Of Lake Velence, Hungary

I studied the area requirement of reedbed breeding passerine birds on 109 reed islands in Lake Velence, Hungary, in the breeding seasons of 1993 and 1994. The size of the smallest occupied reed island for the observed 8 passerine bird species varied from 0.02 ha (Savi’s Warbler Locustella luscinioides) to 4.14 ha (Bluethroat Luscinia svecica). Three species occupied reed islands which were 8–18 times larger than their territory sizes (Sedge Warbler Acrocephalus schoenobaenus, Moustached Warbler A. melanopogon, and Bluethroat), three species occurred on reed islands 4–4.5 times larger than territory sizes (Great Reed Warbler A. arundinaceus, Reed Warbler A. scirpaceus, and Reed Bunting Emberiza schoeniclus), and two species occurred on islands half the size of their territory sizes in continuous reedbeds (Bearded Tit Panurus biarmicus, Savi’s Warbler). This may suggest that the latter two species can utilise groups of small patches within a territory. The incidence functions showed that the probability of occurrence of the Moustached Warbler and the Bluethroat was not 1 even on the largest reed islands (7–25.7 ha), while it was 1 for the other 6 species. The importance of landscape matrix type in determining minimum area requirements was demonstrated using data on the occurrence of bird species in reed marshes within an agricultural landscape in the Po Plain (Italy). In this landscape much larger minimum areas were found than at Lake Velence.

Biometrics, sex ratio and migration periods of Reed Buntings Emberiza schoeniclus wintering in the Tajo Basin, Spain

We analysed capture and biometric data of 2,408 Reed Buntings Emberiza schoeniclus ringed at Carrizal de Villamejor, Tajo Basin, Central Spain. Reed Buntings showed a clear sexual size dimorphism; males had longer wings and were heavier than females. Body condition, as determined from the residuals of a regression of weight on wing length, was highest in males, particularly during midwinter. Mean wing length, especially of the males, decreased over the winter, probably due to feather wear and abrasion, but possibly also due to older and larger males departing earlier. Maximum mean weights were recorded in spring pre‐migratory periods and minimum weights occurred in October, during the final stages of autumn migration. Female:male ratios were 3:1 in the population during winter. The ratio was at a minimum in October and at a maximum in March, which suggests that females arrived and left later than males. The earliest males arrive at Carrizal de Villamejor in autumn approximately 10 days before the earliest females, and also depart in spring 10 days sooner.

北海道西部におけるオオジュリンの帰還調査

The incidence of return to their breeding grounds by the Reed Bunting Emberiza schoeniclus was investigated in western Hokkaido during six seasons (1997-2002). During this survey period, a total of 1, 568 individuals (508 adults, 411 juveniles and 639 nestlings) were given leg bands in the breeding season (Apr. 1-Sept. 10). A total of 150 birds were recaptured after one year, indicating the estimated minimum return rate in the next year as being 9.57%. The return rate dropped exponentially over subsequent years, falling to 1% or less 4-5 years later. The rate of return after one year in adult birds, juveniles and nestlings was 14.37%, 10.22% and 5.48%, respectively. There was no difference in the rate of return between adult males and females. It is conceivable that the true return rate may be higher than our estimates, because not all the returned individuals were necessarily captured by the end of this survey period.