PALAEARCTIC MIGRANTS IN NIGERIA

An account is given of the topography, climate and vegetation belts of Nigeria to illuminate the ecology of the Palaearctic migrants to the country. The faunistic relationship of the resident and migrant avifauna is considered and it is shown that approximately one species in six is migrant. It is shown that the more arid vegetation belts support the largest numbers of migrant species, the forest belt supporting only very few species. Some species appear to overfly the most northern areas. Rather few observations of visual migration are available but those known are recorded. A summary of ringing recoveries affecting Nigeria is given and it is shown that there is clear evidence of species returning to the same wintering grounds each year. The status of 135 migrant species is briefly treated and other species are mentioned where negative information is valuable. Calandrella rufescens, Cyanosylvia svecica, and Emberiza hortulana, notmentioned by Bannerman (1930-53) are included and Cettia cetti is recorded from West Africa for the first time. Several species have had their range extended to include Nigeria. A comparison of breeding areas with the Mediterranean/Sahara crossing zones and Nigerian occurrences shows that most terrestrial species in Nigeria move fairly closely to the lines of longitude. Many aquatics, mostly herons and ducks, breed much to the east of the longitude of Nigeria. It is suggested that the unexpected number of Palaearctic migrants which winter in the arid north of Nigeria indicates that food is less scarce than the appearance of the country in the late dry season indicates. There is a great need for an ornithological and ecological research station in Nigeria in an area such as southwest Lake Chad.     

Role of mixed‐species flocks in the use of adjacent savannas by forest birds in the central Cerrado,Brazil

Abstract: We examined the role of mixed‐species flocks for forest birds during their breeding and non‐breeding seasons in the use of savannas adjacent to forests in central Cerrado, Brazil. Transect surveys (n = 64) were conducted in eight savanna patches. Distances of birds from forests were estimated. Recorded birds were classified as members or not of mixed‐species flocks. About half of the bird species recorded in savannas were found in at least one mixed‐species flock. As distance from the forest increased, the number of species in mixed‐species flocks tended not to vary, while the number of species foraging alone or in mono‐specific groups decreased. Thus, for some forest species, participation in mixed‐species flocks allowed a greater use of more distant savannas. This tendency of being in mixed‐species flocks at greater distances from forests also can be interpreted as a reluctance to forage alone or in mono‐specific groups due to higher predation risk in less protective vegetation distant from cover. There was strong seasonal variation in the participation of bird species in mixed‐species flocks. There were significantly more species in mixed‐species flocks than out of these associations in the non‐breeding season, while differences in the breeding season were not significant. These patterns occurred, in part because mixed‐species flocks tended to be more frequent, to have more species and to forage at greater distances from forests during the early non‐breeding season than in other periods. This study suggests that the formation of mixed‐species flocks plays an important role in promoting the use of adjacent savannas by forest birds at forest/savanna boundaries in Cerrado. It also pointed out a novel advantage gained by birds with participation in mixed‐species flocks – greater use of adjacent vegetation patches.     

Fire resilience of ant assemblages in long‐unburnt savanna of northern Australia

Abstract Tropical savannas and rainforests contrast in their flammability and the fire resilience of their associated species. While savanna species generally exhibit high resilience to burning, there is much debate about the fire resilience of forest‐associated species, and the persistence of forest patches in a flammable savanna matrix. Where fire has been excluded, savanna tends on a trajectory towards forest, with an increase in forest‐associated plants and animal species. This study tested the idea that given the high proportion of forest‐associated taxa in long‐unburnt savanna, the fauna of these areas would be expected to exhibit less resilience to fire than the fauna in frequently burnt savannas. The study investigated the immediate and short‐term effects on ant assemblages of re‐introducing fire into long‐unburnt savanna in northern Australia. The ant fauna exhibited high resistance to fires, with no significant short‐term change in mean abundance or species richness; instead, seasonality had a far stronger influence on overall ant activity. Fire caused dramatic declines in dominance of the patchily distributed forest‐associated species Oecophylla smaragdina and Papyrius sp., but had no effect on overall dominance by open savanna species of Iridomyrmex. Dominance by Iridomyrmex pallidus declined, but this was compensated for by increases in I. reburrus, while two other species of Iridomyrmex showed no change. This indicates a high level of functional redundancy among dominant species of Iridomyrmex, which universally dominate open savanna communities, but not of dominant forest‐associated species. Overall, our findings demonstrate a high degree of fire‐resilience of the long‐unburnt savanna ant fauna. Despite the occurrence of forest‐associated species, the high proportion of savanna species persisting in this habitat means that long‐unburnt savanna retains the general response characteristics of frequently burnt savanna.     

The nature of migration in the red admiral butterfly Vanessa atalanta: evidence from the population ecology in its southern range

1. The migrant Vanessa atalanta (L.) occurs throughout Europe and North Africa. In autumn, populations emigrate from northern and central Europe to the Mediterranean region to overwinter. In the spring, the northern range is recolonised by migrants from the south. The dynamics of the species in the winter range is poorly known. 2. From 1994 to 1999, adults and immatures of V. atalanta were monitored all year round in Mediterranean habitats in north‐east Spain. 3. Data showed that the Catalonia lowlands is an area to which V. atalanta migrates to breed during the winter. Migrants arrive in October and early November and initiate a period of intensive breeding. Larval development occurs throughout the winter until a first annual generation of adults appears in early spring. 4. Most of the butterflies emerging in the spring emigrate and leave the area without breeding. The data suggest strongly that recolonisation of the northern range is by these butterflies not by wintering adults. Altitudinal migration also seems to be a common phenomenon, allowing a further summer generation of adults to occur at high elevations within the Mediterranean region. 5. The complex phenology of V. atalanta in its southern range has evolved as a strategy to track larval resources through space and time. Autumn migration coincides with the greatest availability of the main food plant, Urtica dioica L. Late spring migration occurs by the time food quality is decreasing.     

Breeding latitude predicts timing but not rate of spring migration in a widespread migratory bird in South America

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Palearctic migrant birds are declining, including the Northern Wheatear, and some of the causes of these declines are likely to be operating on their wintering grounds in Africa. We examined seasonal and spatial variation in wintering densities of Northern Wheatears in northern Nigeria, and explored the species’ habitat associations on the wintering grounds to assess the likely effects of habitat change in the Sahel on this species. Densities of Northern Wheatears across northern Nigeria were calculated from point count data gathered during two winters (2000 and 2001) using Distance software, and the relationships between Wheatear presence and habitat variables collected from the same points were explored using general linear models. During mid-winter and early spring, densities of Northern Wheatears peaked, with significantly more birds present in western than eastern study sites. The probability of wheatear occurrence was correlated with Balanites and Salvadora tree density and mean tree height. The Northern Wheatear may benefit from the conversion of woodland habitats in the Sahel to more open savanna. However, sites with very low tree densities showed low probabilities of Northern Wheatears being present, suggesting excessive tree clearance may have a negative effect upon the species.     

ABUNDANCE AND SEASONALITY OF THE SAVANNA AVIFAUNA AT PORT MORESBY, PAPUA NEW GUINEA

The results of 156 transect counts carried out over 30 months in savanna of the Coastal Hill Zone, Port Moresby, Papua New Guinea, are analysed. The avifauna is depauperate compared to similar habitats in New Guinea and temperate Australia. Twelve common species of the Port Moresby savannas were not so in the Coastal Hill Zone and reasons for their rarity are given. Most species present are solely savanna forms but some are dependent upon the presence of small patches of monsoon forest. Average density of birds was estimated at 55 per 10ha, a very low figure compared to New Guinean rainforests. Carnivores and mixed-feeders make up two thirds of numbers present but frugivores, because of their large individual size, are a significant proportion of biomass. There was little significant seasonal difference in overall numbers except for granivores which decline in numbers during the wet season. However, individual species show regular seasonal fluctuations reasons for which are postulated. A correlation exists between flowering of trees and numbers of certain species, and also between the annual grass-fires and numbers of certain grassland species. Merops ornatus, Lalage sueurii and Coracina novaehollandiae, considered in the literature to be wintering migrants, are also shown to be breeding residents. Breeding records for 462 species were analysed. Most breeding of insectivores and mixed-feeders occurs in the Austral spring during the dry season and ends before the onset of heavy rains. Granivores breed in the late wet season. The few records for frugivores indicate a wet season peak.     

Forms of rarity of tree species in the southern Brazilian Atlantic rainforest

The assessment of species rarity considers local abundance (scarce or abundant population), habitat affinity (stenoecious or euryecious species), and geographic distribution (stenotopic or eurytopic species). When analyzed together these variables classify species into eight categories, from common species to those having small populations, unique habitats, and restricted geographic distribution (form 7), as proposed by Rabinowitz in 1981. Based on these categories, it is possible to calculate the frequency of the different forms of rarity of the species present in a given site. The Brazilian Atlantic rainforest is considered a hotspot of the world biodiversity harboring many endemic species, which have restricted geographic distribution. Our objective was to identify the forms of rarity of tree species and their proportions in the southern portion of the Brazilian Atlantic rainforest using Rabinowitz’s forms of rarity. All the seven forms of rarity are present in the 846 tree species we analyzed: 46% eurytopic and 54% stenotopic, 73% euryecious and 27% stenoecious, 76% locally abundant and 24% locally scarce species. Eurytopic, euryecious locally abundant species accounted for 41.1%, whereas 58.9% were somehow rare: 4.5% eurytopic, euryecious locally scarce, 0.2% eurytopic, stenoecious locally abundant, 0.1% eurytopic, stenoecious locally scarce, 19.5% stenotopic, euryecious locally abundant, 8.0% stenotopic, euryecious locally scarce, 15.6% stenotopic, stenoecious locally abundant, and 11.0% stenotopic, stenoecious locally scarce. Considering that the most restrictive forms of rarity precedes extinction, the application of Rabinowitz’s system demonstrated that most tree species of the southern Brazilian Atlantic rainforest are threatened due to their restricted geographic distribution, restriction to a single habitat, reduced local abundance, or even to a combination of these variables.     

Postbreeding elevational movements of western songbirds in Northern California and Southern Oregon

Migratory species employ a variety of strategies to meet energetic demands of postbreeding molt. As such, at least a few species of western Neotropical migrants are known to undergo short‐distance upslope movements to locations where adults molt body and flight feathers (altitudinal molt migration). Given inherent difficulties in measuring subtle movements of birds occurring in western mountains, we believe that altitudinal molt migration may be a common yet poorly documented phenomenon. To examine prevalence of altitudinal molt migration, we used 29 years of bird capture data in a series of linear mixed‐effect models for nine commonly captured species that breed in northern California and southern Oregon. Candidate models were formulated a priori to examine whether elevation and distance from the coast can be used to predict abundance of breeding and molting birds. Our results suggest that long‐distance migrants such as Orange‐crowned Warbler (Oreothlypis celata) moved higher in elevation and Audubon's Warbler (Setophaga coronata) moved farther inland to molt after breeding. Conversely, for resident and short‐distance migrants, we found evidence that birds either remained on the breeding grounds until they finished molting, such as Song Sparrow (Melospiza melodia) or made small downslope movements, such as American Robin (Turdus migratorius). We conclude that altitudinal molt migration may be a common, variable, and complex behavior among western songbird communities and is related to other aspects of a species’ natural history, such as migratory strategy.     

Restoration of Midwestern U.S. Savannas: One Size Does Not Fit All

Lowland savannas are a rare variant of Midwestern United States savanna occurring on alluvial soils, for which reference information is sparse. To evaluate the appropriateness of using upland savanna as a surrogate source of reference information for lowland savanna, we studied a pre‐Euro‐American lowland savanna using original U.S. Public Land Survey data and other historical records. Historical vegetation was reconstructed and compared among upland savannas, lowland savannas, and lowland forests; we also evaluated potential disturbance dynamics maintaining these systems. We found that all three communities were dominated by members of the genus Quercus but also had extensive representation by many other tree species, especially notable for savannas in this region. There were no clear size–density relationships for species in the genus Quercus, indicating that these historical savannas were not characterized exclusively by large, scattered oak trees but rather by trees of many oak species and nonoak species in a wide range of size classes. Both upland and lowland savannas also contained a substantial shrub component. We found no evidence that lowland savannas were maintained by flooding, although the uneven‐aged canopy structure suggested that periodic disturbance occurred. Restoration of lowland savanna in this region should include provisions for maintaining nonoak species and shrubs, with disturbance timed to maintain an uneven‐aged canopy structure. Although the appropriateness of historical data in the face of climate change may be questionable, in this region, a warmer climate may actually help promote the “oak parkland” that was present from 8,000 BP up to Euro‐American settlement.     

Floristic composition,plant species abundance,and soil properties of montane savannas in the Gran Sabana,Venezuela

Floristic composition, species abundance, and soil properties were studied in slope, flat and disturbed savannas in the northern part of the Gran Sabana, Venezuela. All savannas presented shallow soils (<30 cm depth) with high content of sand and low content of clay. In general, the soils were poor in nutrients and strongly acidified. The major difference between the soils was the content of the stony fraction, which was significantly higher (P<0.05) in the slope savannas than in the flat savannas. A total of 57 dicot, 42 monocot, and 7 fern species were recorded in all studied savannas. In the flat and slope savannas predominated the monocot species, while in the disturbed savanna predominated the dicots. The families with the largest number of species were Poaceae (19.8%), Cyperaceae (13.2%), Asteraceae (10.4%) and Melastomataceae (8.5%). The number of species in the flat savannas was higher than that of the slope savannas. The lowest plant species richness was associated to slope savannas and their high content of stony fraction of the soils. The highest floristic similarity was found between slope savannas, and the lowest between disturbed savanna and slope savannas. The most abundant life forms in the studied savannas were perennial (42.4%) and annual (24.5%) herbs, followed by suffruticoses (16.0%) and shrubs (12.3%), and the less frequent was lianas (4.7%). The disturbed savanna showed the higher richness and diversity index. Trachypogon plumosum (Poaceae) was the most abundant species in all studied savanna.     

Patterns in departure phenology and mass gain on African non‐breeding territories prior to the Sahara crossing in a long‐distance migrant

Afro‐Palaearctic migrants are declining to a greater degree than other European species, suggesting that processes occurring in Africa or on migration may be driving these trends. Constraints on food availability on the wintering grounds may contribute to these declines but little is known about when and where these resource constraints may occur. Sufficient resources are particularly important prior to spring migration, when migrants must cross the Sahara Desert. We examined mass gain and departure phenology in a long‐distance Palaearctic passerine migrant to determine the degree to which pre‐migratory fattening occurs in their long‐term non‐breeding territories in the Guinea Savannah region of Africa. We monitored 75 Whinchats Saxicola rubetra for departure from their non‐breeding territories in one spring, and analysed mass data of 377 Whinchats collected over three non‐breeding seasons plus 141 migrating Whinchats caught in April over 8 years, all within the same few square kilometres of human‐modified Guinea Savannah in central Nigeria. Whinchats left their winter territories throughout April, with males departing on average 8 days earlier than females. However, there was no evidence that time of departure from territory was linked to age, body size or mass at capture. Whinchats departed their territories with a predicted mass of 16.8 ± 0.3 g, considerably less than the c. 24 g required for the average Whinchat to cross the Sahara directly. Comparing departure dates with arrival dates in southern Europe showed a discrepancy of at least 2 weeks, suggesting that many Whinchats spend considerable time on pre‐migratory fuelling outside their winter territory prior to crossing the Sahara. Overwintering birds gained mass slowly during February and March (0.03 g/day), and non‐territorial or migrating birds at a much higher rate in April (at least 0.23 g/day), with up to 20% of migrating Whinchats in April potentially having sufficient fuel loads to cross the Sahara directly from central Nigeria. Our results suggest that most Whinchats leave their winter territories to fatten up locally or, possibly, by staging further north, closer to the southern limit of the Sahara. Resource constraints are therefore likely to be particularly focused in West Africa during mid‐April and possibly at staging areas before the crossing of the Sahara Desert.     

Habitat selection and coexistence of migrants and Afrotropical residents

In this paper I discuss factors that influence the habitat choice of small migrant birds on their Afrotropical wintering grounds and the ecological isolation of migrants and residents. The main characteristic of migrants is the use of resources which are sporadic in space and time. The majority of migrants occur in seasonal savannas and open woodland, mostly using temporarily and locally abundant food sources generally unused by residents. Migrants are more eurytopic and exploit more open parts of the habitats than ecologically similar tropical species. In some guilds, the foraging speed and rate of migrants is higher and they use their wings more often in comparison to residents. There is weak evidence that niche shifts of residents are induced by the arrival of migrants. Overt interspecific interactions seem to be infrequent, except in a guild of ground-feeding birds which rely on a rather predictable but poor food supply. In this guild, residents, but not intra-African migrants, dominated Palaearctic migrants in aggressive encounters irrespective of body-size. In contrast to this, dominance was size-dependent among wintering Palaearctic migrants.     

Seed set in Sorghum stipoideum,and not fire,determines the timing of breeding by Gouldian finches (Erythrura gouldiae)

Seeds of native grasses are an important food source for granivorous finches throughout the tropical savannas of northern Australia. The iconic Gouldian finch (Erythrura gouldiae), a threatened species endemic to these savanna grasslands, relies almost exclusively on the grass seeds of annual Sorghum spp. when breeding, and appears to time breeding with the availability of these seeds. Fire is common throughout the savanna grasslands of northern Australia and has the potential to alter Sorghum spp. seed germination and plant reproductive phenology which in turn could alter the Gouldian finch breeding phenology window. This study examines if the temporal relationship between breeding by Gouldian finches in the north‐east Kimberley region of Australia relates to fire and Sorghum stipoideum seed phenology. The availability of S. stipoideum seed was monitored at Gouldian finch breeding sites in association with local fire history and Gouldian finch breeding data. The effect of experimental fire (heat and smoke) on S. stipoideum seed dormancy and germination was also investigated. We found that the first heavy rainfalls preceded germination of S. stipoideum in November/December. Synchronous seed set by S. stipoideum plants the following March/April coincided with the start and duration of the Gouldian finch breeding season. The timing of dry season fires had no relationship with seed dormancy or the phenology of seed germination and seed set. Nor did the effects of smoke or heat affect seed dormancy and germination. These findings support the importance of the seed phenology of annual grass species, such as S. stipoideum, to breeding Gouldian finches, and also suggest that the occurrence of fire at a breeding site in the previous year does not alter the S. stipoideum seed or finch breeding window. The implications of these results for threatened Gouldian finch ecology and management are discussed in relation to previously published fire impacts on S. stipoideum seed nutrition and finch breeding site selection.     

Narrow-Front Loop Migration in a Population of the Common Cuckoo Cuculus canorus,as Revealed by Satellite Telemetry

Narrow migration corridors known in diurnal, social migrants such as raptors, storks and geese are thought to be caused by topographical leading line effects in combination with learning detailed routes across generations. Here, we document narrow-front migration in a nocturnal, solitary migrant, the common cuckoo Cuculus canorus, using satellite telemetry. We tracked the migration of adult cuckoos from the breeding grounds in southern Scandinavia (n = 8), to wintering sites in south-western Central Africa (n = 6) and back to the breeding grounds (n = 3). Migration patterns were very complex; in addition to the breeding and wintering sites, six different stopover sites were identified during the 16,000 km annual route that formed a large-scale clockwise loop. Despite this complexity, individuals showed surprisingly similar migration patterns, with very little variation between routes. We compared observed tracks with simulated routes based on vector orientation (with and without effects of barriers on orientation and survival). Observed distances between routes were often significantly smaller than expected if the routes were established on the basis of an innate vector orientation programme. Average distance between individuals in eastern Sahel after having migrated more than 5,000 km for example, was merely 164 km. This implies that more sophisticated inherent guiding mechanisms, possibly involving elements of intermediate goal area navigation or more elaborate external cues, are necessary to explain the complex narrow-front migration pattern observed for the cuckoos in this study.     

Evidence for indigenous selection and distribution of the shea tree, Vitellaria paradoxa, and its potential significance to prevailing parkland savanna tree patterns in sub-Saharan Africa north of the equator

Aim Woody vegetation patterns in African savannas north of the equator are closely connected to human presence, but the distinctions between natural and anthropogenic landscapes have not been clear to many observers. Criteria for identifying savanna landscapes on a continuum of intensity of anthropic impact are explored. Methods A key savanna tree species, Vitellaria paradoxa (Sapotaceae), was used as model for evaluating anthropic impact. Fruits harvested from tree populations across the species range were analysed for variation in traits valued by indigenous peoples. A simple selection index was used to scale tree populations from a hypothetical wild state to a hypothetical domesticated state. Index values were compared with trait values along climate zone gradients and evaluated in the context of indigenous savanna management practices and historical species distribution reports. Results Trait values such as fruit size and shape, pulp sweetness, and kernel fat content show a significant influence of temperature and rainfall. At the same time, the mean values of groups of traits vary perpendicular to the general climatic zone gradient. Selection index values between Vitellaria populations vary up to sixfold, with highest values in central Burkina Faso. Comparison of present day Vitellaria distribution with historical range limits show range expansion by human migration. Main conclusions The prevalence of major economic tree species in the savannas of Africa north of the equator is a strong indicator of human involvement in tree dispersal. This conclusion is supported by paleobotanical evidence and by recent Vitellaria range expansion as a result of human migration. The presence of high mean values of several Vitellaria fruit traits in central Burkina Faso suggests that selection for desired characteristics has occurred. The impact of indigenous savanna peoples on woody species composition and spatial distribution is probably much greater than usually thought and is the result of a deliberate strategy of altering the landscape to provide needed human resources.     

Perspectives on Palaearctic and Nearctic bird migration; comparisons and overview of life-history and ecology of migrant passerines

In this paper we compare ecological attributes of tropical migrant passerines from the Nearctic and western Palaearctic, focusing particularly on habitat association patterns during both breeding and wintering seasons. Three regions were compared: Europe, western and eastern North America. Breeding bird census data from 32 studies (each including at least four stages of forest succession) were used to assess the association patterns of breeding habitats among tropical migrants. For each species we calculated an index of habitat diversity and habitat preference.
Tropical migrants preferred earlier successional stages than other birds in Europe. The opposite was true in eastern North America. In eastern North America, tropical migrants tended to be associated with a smaller range of serai stages than other passerine species. In their winter quarters, Palaearctic migrants live primarily in open habitats, such as savannas, whereas eastern Nearctic migrants make more frequent use of evergreen forests. Migrants from western North America show the greatest match between breeding and wintering habitats.
We relate the results to the taxonomy and probable history of contemporary avifaunas and vegetation formations of the Old and New World. Taxonomically, tropical migrants from different parts of the Holarctic are less closely related to each other than residents and short-distance migrants. Tropical and temperate avifaunas are more closely related to each other in the New World than in the Old World. Conservation implications of the between-continent differences are briefly discussed.     

MIGRATION OF THE NORTHWESTERN EUROPEAN POPULATION OF THE CUCKOO CUCULUS CANORUS, AS SHOWN BY RINGING

The migration of the Cuckoo Cuculus canorus is described from recoveries of ringed birds. Young birds begin to migrate in August and most go southwards by September—those in continental Europe move southeast, south or southwest, while those from the British Isles move southeast. In spring, migrants arrive in Europe in April/May, second-(calendar) year birds doing so later than post-second-year birds. In autumn old birds depart in advance of first-year birds; and the individual bird may move stepwise through Europe. Old birds showed a marked tendency to return to the same places inhabited in previous breeding seasons, and birds ringed as nestlings subsequently tended to return to the general vicinity of the natal site.     

Reverse migration as a cause of vagrancy

Capsule Reverse migration in autumn does not occur to the same degree in all species of migrants, but is related to migratory direction.

Aims To identify factors determining degree of reverse migration and specifically to test whether it occurs in long-distance migrant species irrespective of their standard (normal) migration direction. Methods Multiple regression analysis on the number of individuals occurring as reverse migrants observed in northwest European countries.

Methods Multiple regression analysis on the number of individuals occurring as reverse migrants observed in northwest European countries.

Results The number of reverse migrants observed in northwest European countries is strongly correlated with standard migratory direction, estimated population size and detectability, but an effect of the distance travelled from the breeding areas is not supported. The pattern holds true for subsamples of the data set, including British and Irish records or Scandinavian records only, and when controlling for phylogeny.

Conclusion Birds that migrate eastward in autumn from their breeding grounds, mostly in eastern Europe, are more likely to consistently reverse migrate than those species migrating southward mostly from southern Europe.     

Perceived wintering latitude determines timing of song output in a migratory bird

Migratory bird populations frequently consist of individuals that overwinter variable distances from the breeding site. Seasonal changes in photoperiod, which varies with latitude, underlie seasonal changes in singing frequency in birds. Therefore, migratory populations that consist of individuals that overwinter at different latitudes with large overwintering ranges could experience within‐population variation in seasonal production of song. To test the influence of overwintering latitude on intrapopulation variance in song production in the spring, we subjected two groups of Eastern Song Sparrows (Melospiza melodia melodia) from the same partially migratory breeding population to different photoperiodic schedules associated with a 1,300‐km difference in overwintering location. One group remained on the natural photoperiodic schedule of the breeding site (resident group) while the other group experienced a nonbreeding photoperiod that mimicked a southern migration in the fall followed by a northern migration back to the breeding site in the spring (migratory group). We compared song output between the two groups in three different stages (nonbreeding, prebreeding, and breeding). Little singing occurred during nonbreeding stage sample dates (20 November, 6 December) for the resident group, and no singing occurred for the migrant group. During the prebreeding stage (27 January, 7 February), significantly more singing occurred in the resident group than in the migrant group. During the breeding stage (21 March, 4 April), after a simulated migration for the migrants, song output was similar in both groups. These results suggest that within‐population variation in wintering latitude may contribute to variation in seasonal changes in singing behavior, which may covary with readiness to breed. Studies utilizing confirmed migrants and residents, rather than merely simulated migrants and residents, are also needed to better understand these processes.