The importance of traditional farmland areas for steppe birds: a case study of migrant female Great Bustards Otis tarda in Spain

A detailed knowledge of the habitat requirements of steppe birds living in farmland habitats is necessary to identify agricultural practices compatible with their conservation. The globally threatened Great Bustard Otis tarda is a partial migrant in central Iberia, but factors affecting its winter habitat use have not been identified. We assessed habitat differences between breeding and wintering areas and winter habitat selection of radiotagged migrant female Great Bustards in central Spain. Of 68 tagged females, 35% moved to wintering areas located 64.3 ± 24.0 km south of their breeding areas, and 80% wintered in a single area of c. 236 km². A census of the population in this area identified it as one of the most important wintering areas of this species in the world, holding c. 1500 individuals. There were significant differences between breeding and wintering habitats of individually marked migrant females. Compared with breeding areas, wintering areas of migrant females were located further from roads and urban nuclei, had lower human population densities and area of urban developments, and a higher diversity of land‐use types, with less cover of cereals and more vineyards and olive groves. Within this area, radiotracked migrant females preferred sites with more vineyards and a lower land‐use diversity. Our results highlight the importance of traditional Mediterranean dry farmland mosaics, and suggest that different conservation strategies are needed for migrant and resident populations in winter to secure the conservation of suitable wintering habitat for Great Bustards in the Iberian Peninsula.     

Regional variation in seasonality affects migratory behaviour and life-history traits of two Mediterranean passerines

Migratory birds may improve fecundity by moving to seasonal breeding areas, but may also suffer higher mortality rates as a cost of movement. However, the covariation among seasonality, migratoriness and life histories should change between species if their ecological features affect site-tenacity, survival or fecundity. In frugivorous birds, for instance, wandering in search of fruits may trigger broader migrations than territorial defence, and also may improve nonbreeding survival by preventing food shortages that eventually happen in discrete territories. We studied the variation in spatio-temporal distribution, life expectancy and fecundity in robins (Erithacus rubecula) and blackcaps (Sylvia atricapilla) distributed in three Iberian regions with a low, mid or high degree of environmental seasonality. In the Iberian Peninsula, robins and blackcaps are the two most intensive frugivores in winter; however, robins are territorial while blackcaps track fruit abundance among habitat patches. In the most seasonal area, robins and blackcaps decreased abundance in winter and showed a lower breeding-site tenacity, a shorter life expectancy and a larger clutch size. However, blackcaps tended to be more migratory than robins in all regions. Despite their stronger migratory behaviour, blackcaps showed a longer life expectancy and a smaller clutch size than robins in all regions. In robins, winter territoriality could decrease nonbreeding survival but also improve fecundity, because survivors are dominant and hence more efficient breeders. In blackcaps, however, the use of the most profitable habitat patches could improve nonbreeding survival, thereby allowing a similar recruitment than in robins with a lower reproductive investment. These results support that regional-scale changes in seasonality may affect migratory behaviour and hence the tradeoff between reproduction and survival in birds, doing so differently depending on the idiosyncrasy of each species.     

Territoriality,philopatry, and nest-site fidelity in robins trapped in Moscow oblast

From 1999 to 2005 at Zvenigorod Biological Station (Moscow oblast, Russia, 55°44′N, 36°51′E) field studies were performed. Birds were trapped using mist-nets. The Russian Ringing Center provided data collected from 1948 on robins captured outside the Moscow oblast. A total of 5751 robins were trapped and banded in the Moscow oblast. Only two birds (0.03%) were retrapped the following years. Three birds banded in the Moscow oblast were found in other regions. In addition, two robins banded in other countries were caught at Zvenigorod Biological Station. The rate of long-distance recoveries was 0.09%. The Russian Ringing Center reports on three robins banded in other countries and found in the Moscow oblast, and one robin banded in the Moscow oblast and then found in a different country. It was shown that robins born or breed in the Moscow oblast exhibited neither nest-site fidelity nor natal homing, which is the case for other areas. Wintering grounds of robins born or breed in the Moscow oblast are located within a single zone (north-east of Spain, south of France and Italy). This area is also wintering ground for robins from other regions. There exists one route connecting the wintering grounds for robins with the Moscow oblast which birds follow during autumn and spring migrations. It is possible that the Moscow oblast is a nesting area for robins born or breed in the north of Russia (including Finland and the Leningrad oblast). Natal sites and nest sites of robins could be separated by a distance of 1000 km or more.     

Use of ring recoveries to predict habitat suitability in small passerines

Aim Abundance of small passerines may be distributed over large wintering areas according to geographical patterns that are difficult to detect. This may prevent the identification and conservation of the most suitable sectors, or the detection of local and regional features affecting the species during winter. In this paper, we explore the usefulness of ring recoveries to predict bird distribution in wintering grounds by using Maxent, one of the presence‐only techniques available for modelling species distributions. We test whether suitability indices obtained in 2.5 × 2.5 km UTM squares from ring recoveries were positively correlated with the actual abundance of robins (Erithacus rubecula) and blackcaps (Sylvia atricapilla) inside the squares. Location Spain. Methods We used 686 and 1139 localities across the country in which blackcap and robin ring recoveries were recorded by the Spanish Office of Migratory Species to generate the suitability maps. In addition, we sampled bird abundance inside 70 control squares independent of ring recovery localities along a belt crossing mountains, highlands and lowlands of the Iberian Peninsula during January from 2006 to 2011. Results Suitability indices predicted by Maxent were positively correlated with robin (r = 0.42, n = 70, P < 0.001) and blackcap (r = 0.52, n = 70, P < 0.001) abundances in the 70 control squares along the belt crossing the Iberian Peninsula. Main conclusions These results suggest that the use of distribution models with ring recoveries may be used to describe the habitat suitability of the winter ranges of small, common passerines. This also means that the huge number of ring recoveries stored in national and transnational data banks could be used to explore the factors shaping bird ranges and to forecast the geographical distribution of suitable wintering areas of migratory birds in large, poorly known regions. This may be useful in biogeography and conservation.     

Resident and transient dynamics, site fidelity and survival in wintering Blackcaps Sylvia atricapilla: evidence from capture–recapture analyses

In their winter quarters, migrant birds may either remain within a small area (resident strategy) or move frequently over a large area looking for locally abundant food (transient strategy). It has been suggested that both strategies could simultaneously occur in the same population. We used time-since-marking capture–recapture models to infer the coexistence of these two behavioural strategies (transient and resident) among wintering Blackcaps Sylvia atricapilla using weekly recapture data over a 7-year period. A related question is whether Blackcaps, if surviving to the next winter, always return to the same wintering area, so we also used this approach to analyse winter site fidelity and to estimate annual survival probabilities. Model selection supported the existence of heterogeneity in survival estimates for both the within-season and the interannual survival probabilities, i.e. there was evidence for the existence of transients. It was estimated that 26% of the Blackcaps were resident during the winter. Mean apparent annual survival probability was 0.46 (se = ±0.11). However, there was some evidence suggesting that not all individuals showed winter site fidelity. The estimated proportion of individuals that, if alive, returned to the wintering area was 28%. This is the first study to show the existence of these two behavioural strategies (residence and transience) among wintering Blackcaps, and the first confirming this pattern using capture–recapture models. These models considering transient and resident dynamics may become an important tool with which to analyse wintering strategies.     

北京十渡自然保护区越冬黑鹳的种群生态调查

为了解黑鹳在北京地区越冬的生态特点,于2004年1月至2007年3月采用直接观察法对北京市拒马河自然保护区越冬黑鹳的数量、栖息地选择和取食规律进行了观察。结果表明拒马河流域已成为北京地区越冬黑鹳稳定的栖息地,种群数量超过20只。越冬聚群从11月开始,分群时间为次年2月。取食地相对集中,取食活动在越冬初期以上午和中午为主,中期以下午为主,末期则分为早晚两个时段。干旱和人为活动导致的适宜取食地减少是影响黑鹳生存的主要因素。     

Temporal shifts in the pair-bond dynamics of New Zealand robins (

Winter is a challenging time for temperate insectivorous songbirds, due to colder temperatures, reduced prey activity and shorter diurnal foraging times. For species that are non-migratory, territorial and monogamous, winter conditions may result in within-pair competition. However, little is known about how monogamous pairs coexist on their winter territories. We investigated temporal patterns in male?female interactions of the New Zealand robin (Petroica australis to better understand mechanisms of coexistence during winter. Previous work has shown that male robins are physically dominant over females and maintain priority access to food year-round. We quantified female behaviour throughout the 2008 non-breeding season to better understand how females coexist with physically dominant males on winter territories. Results showed that pairs rarely forage in close proximity in autumn and winter, suggesting females avoid males at this time of year. Males and females begin to spend more time foraging together as winter turns to spring. During this winter?spring transitional period, females steal large amounts of food hoarded by males. These results indicate that male and female New Zealand robins use different behavioural mechanisms to coexist on their winter territories. While males are dominant physically, females show a seasonally variable strategy where they avoid males in autumn and winter, and then steal male-made caches from early spring until the onset of inter-pair cooperation and the breeding season.     

Frugivory of transient and wintering European robins Erithacus rubecula in a Mediterranean region and its relationship with ornithochory

Stomach contents of 209 dead and droppings of 57 mist-netted migrating or wintering European robins Erithacus rubecula in a Mediterranean area in southern France showed the following seasonal trends: (1) a dominance of invertebrates in early autumn, (2) a dominance of fruits in mid-autumn, (3) acorns being important in midwinter, and (4) a strong dominance of invertebrates at the end of winter and in early spring.
The fruits of 23 plant species had been consumed. The most widespread and abundant ones were also the most commonly taken ( Rubia peregrina at the regional level and Viburnum tinus at a local one). The size of these fruits ranged from 4 to 12 mm. mostly between 6 and 8 mm. Owing to the amount of fruits consumed and the numbers of birds involved, the European robin is one of the few main dispersers of the numerous fleshy-fruited plant species of the Mediterranean area. Nevertheless, a correct evaluation of its role is only possible within the dense network existing between these plant species and all their dispersers (mainly birds but also mammals).     

Assessment of hybridisation between the endangered Chatham Island black robin (<Emphasis Type="Italic">Petroica traversi</Emphasis>) and the Chatham Island tomtit (<Emphasis Type="Italic">Petroica macrocephala chathamensis</Emphasis>)

Hybridisation between an endangered species and a more common species can facilitate population decline and extinction of the endangered species due to wasted reproductive effort, outbreeding depression and/or swamping of alleles due to widespread or complete admixture. The Chatham Island black robin (Petroica traversi) is an endangered songbird species, which was reduced to only five individuals in 1980. Intensive cross-fostering, whereby black robin offspring were placed into nests of the closely related Chatham Island tomtit (Petroica macrocephala chathamensis) to increase reproductive output, contributed to the rapid recovery of the species within 10 years. Several hybridisation events occurred and although those hybrids were successfully eliminated from the population, concerns remained for the possibility of introgression between the two species that may have gone unnoticed. In this study, we genotyped seven microsatellite loci in both species from the two islands where they coexist, to assess the level of hybridisation and the extent of introgression between the two species. The two species shared no alleles at five of the seven loci genotyped, and cluster analysis, AMOVA and admixture analysis of a total of 174 black robins and 78 Chatham Island tomtits showed no evidence of hybridisation or introgression on either of the two islands where they co-exist. As a result, there is no evidence that black robins are currently in any danger of population decline or extinction through hybridisation with tomtits, although small population size and skewed sex ratio, particularly in the smaller of the two populations, may facilitate future hybridisation events.     

Do migratory pathways affect the regional abundance of wintering birds? A test in northern Spain

Aim The abundance distribution of organisms at regional scales is commonly interpreted as the result of spatial variation in habitat suitability. However, the possibility that geography itself may affect patterns of distribution has received less attention. For example, the abundance of wintering bird populations might be influenced by the cost of reaching areas located far away from the main migratory pathways. We studied the abundance distribution of three common migratory passerines (meadow pipits, Anthus pratensis; common chaffinches, Fringilla coelebs; and European robins, Erithacus rubecula) wintering in farmlands located in the 600‐km long Cantabrian coastal sector of northern Spain, roughly perpendicular to the west Pyrenean migratory pathway that drives European migrant birds into the Iberian Peninsula. Location The study area occupies a belt located between the Atlantic coast and the Cantabrian Mountains in northern Spain. Methods We counted wintering and breeding birds and measured the structure of vegetation and environmental variables (altitude, rainfall, temperature) in 68 farmlands distributed at different distances from the west Pyrenean migratory flyway. We also studied the distribution of birds ringed in central and northern Europe and recovered in the study area between October and February. Analyses were based on single univariate statistics (chi‐square tests), ordination by principal components analysis and multiple regression. Results Controlling for the effects of climate, vegetation structure and local abundance of breeding conspecifics, the winter abundance of all three species decreased with the distance from their main migratory route in the western Pyrenees. Such patterns fitted well to the observed distribution of ringing recoveries. Main conclusions Our results support a link between the movements of birds along the Pyrenean migratory pathway and their winter abundance in northern Spain. According to this view, the sectors located near the migratory pathway seem to be more easily occupied by migrants, supporting the idea that proximity to passage areas may explain the fine‐grain regional patterning of species abundance in wintering grounds.     

Comparing the seasonal survival of resident and migratory oystercatchers: carry‐over effects of habitat quality and weather conditions

Events happening in one season can affect life‐history traits at (the) subsequent season(s) by carry‐over effects. Wintering conditions are known to affect breeding success, but few studies have investigated carry‐over effects on survival. The Eurasian oystercatcher Haematopus ostralegus is a coastal wader with sedentary populations at temperate sites and migratory populations in northern breeding grounds of Europe. We pooled continental European ringing‐recovery datasets from 1975 to 2000 to estimate winter and summer survival rates of migrant and resident populations and to investigate long‐term effects of winter habitat changes. During mild climatic periods, adults of both migratory and resident populations exhibited survival rates 2% lower in summer than in winter. Severe winters reduced survival rates (down to 25% reduction) and were often followed by a decline in survival during the following summer, via short‐term carry‐over effects. Habitat changes in the Dutch wintering grounds caused a reduction in food stocks, leading to reduced survival rates, particularly in young birds. Therefore, wintering habitat changes resulted in long‐term (>10 years) 8.7 and 9.4% decrease in adult annual survival of migrant and resident populations respectively. Studying the impact of carry‐over effects is crucial for understanding the life history of migratory birds and the development of conservation measures.     

Moderate inbreeding depression in a reintroduced population of North Island robins

Reintroductions of threatened species are increasingly common in conservation. The translocation of a small subset of individuals from a genetically diverse source population could potentially lead to substantial inbreeding depression due to the high genetic load of the parent population. We analysed 12 years of data from the reintroduced population of North Island robins Petroica longipes on Tiritiri Matangi Island, New Zealand, to determine the frequency of inbreeding and magnitude of inbreeding depression. The initial breeding population consisted of 12 females and 21 males, which came from a large mainland population of robins. The frequency of mating between relatives ( f >0; 39%, n =82 pairs) and close relatives ( f =0.25; 6.1%) and the average level of inbreeding ( f =0.027) were within the range reported for other small island populations of birds. The average level of inbreeding fluctuated from year to year depending on the frequency of close inbreeding (e.g. sib–sib pairs). We found evidence for inbreeding depression in juvenile survival, with survival probability estimated to decline from 31% among non-inbred birds ( f =0) to 11% in highly inbred juveniles ( f =0.25). The estimated number of lethal equivalents based on this relationship (4.14) was moderate compared with values reported for other island populations of passerines. Given that significant loss of fitness was only evident in highly inbred individuals, and such individuals were relatively rare once the population expanded above 30 pairs, we conclude that inbreeding depression should have little influence on this robin population. Although the future fitness consequences of any loss of genetic variation due to inbreeding are uncertain, the immediate impact of inbreeding depression is likely to be low in any reintroduced population that expands relatively quickly after establishment.     

Partial migration in inexperienced pied avocets Recurvirostra avosetta: distribution pattern and correlates

Birds exhibit a range of wintering behaviour from strictly migrant to strictly resident species. In partially migrating ones, some birds overwinter within their breeding region (resident birds) while others, although breeding in the same area, winter far away (migrant birds). Accordingly, choosing a wintering region is a key stage in the annual life cycle of birds, notably for inexperienced first‐year individuals. The present study aimed to investigate this issue, and more specifically to study the distribution pattern during winter and factors influencing the wintering behaviour of first‐year pied avocets Recurvirostra avosetta. Based on a 10‐yr ringing study carried out on five of the major French breeding colonies distributed along the Atlantic coast, we showed the coexistence of different wintering tactics. The resident tactic was predominant (approximately 86% of the 575 birds re‐sighted), while the other birds adopted migration. Among resident individuals, two different tactics occurred: 43% of birds overwintered within their natal colony, whereas the others wintered in another site located at relatively close proximity along the French Atlantic coast. Hatching date was a consistent predictor of all wintering tactics. More specifically, the probability of migrating was the highest for early‐hatched birds, and for resident ones, the probability of wintering within their natal colony rather than in another French site was the highest for both median‐ and late‐hatched individuals. In addition, a colony effect was demonstrated for resident birds. Several biological interpretations, including social system, variations in both individual body condition and habitat quality, were put forward to explain these correlates.     

Fruit tracking between sites and years by birds in Mediterranean wintering grounds

Knowledge of the ability of birds to track spatiotemporal variation in fruit distribution is essential for understanding plant-frugivore interactions. Arguably, although total fruit availability sets an upper limit to the number of birds that can exploit a habitat patch, not all species can equally distribute abundance according to variation in fruit resources. To explore this, we studied bird and fruit abundance in 1999–2005 in Mediterranean scrublands and woodlands of southern Spain. We analysed whether changes of fruit abundance in eight different sites during six winters could predict numerical changes of a set of frugivorous passerines of the area (blackcap Sylvia atricapilla , Sardinian warbler S. melanocephala , robin Erithacus rubecula , song thrush Turdus philomelos and blackbird T. merula ). We also investigated if all frugivores together tracked fruits better than individual species, thereby supporting a shared use of resources. Results showed strong inter-specific differences. Only the most abundant species (blackcaps and robins) tracked the spatial patterning of food despite strong differences in the use of space (vagrant and territorial, respectively). This suggests plastic behaviour of territorial robins, with individuals changing from strictly territorial to wandering, a flexibility that would favour between-site numerical arrangements according to food resources. Annual changes in bird numbers were independent of the availability of fruits, except for blackcaps, an abundant vagrant bird that tracked inter-winter changes in fruit abundance. The abundance of blackcaps fitted the spatiotemporal patterning of fruit resources better than the whole guild of frugivorous birds, inconsistent with the idea that these species track together the changing availability of fruit resources.     

Demographic and spatial responses of resident bird populations to the arrival of migratory birds within an urban environment

Long-distance migration allows many bird species to overcome the severe climatic changes that occur in seasonal environments. Migration is highly demanding, and given its cyclical nature, we currently know that it has substantial effects on the population parameters of migratory birds during both breeding and wintering seasons. However, the potential effects of the presence of migratory birds in their wintering grounds on populations of resident birds have remain largely unexplored. Here, we propose the hypothesis that migratory birds negatively affect the habitat occupancy and population abundance of resident birds because of the arrival of numerous individuals during the most limiting months of the year. Here, we studied different species of migratory and resident birds that coexist during winter in an urban ecological reserve located within Mexico City. We used single-species multiseason occupancy models, two-species occupancy models, and distance sampling techniques to evaluate changes in occupancy and population density of resident bird species during three consecutive winters. We found an aggregation pattern between two resident species (Psaltriparus minimus and Thryomanes bewickii) with three migratory warblers (Cardellina pusilla, Setophaga coronata and Setophaga townsendi). Thus, our results provide evidence of the formation of mixed-species flocks in our study area. We also conclude that resident birds experience different demographic and behavioral processes during winter that not necessarily result from interspecific interactions with migratory birds.     

The effect of an extreme winter on per-capita growth rates in some resident bird populations: an example of r-selection?

Among the breeding birds of an English oakwood studied over a period of 27 years, five species averaged more than 10 pairs. Two of these populations, the robin and especially the wren, crashed after the extreme winter 1962–1963, whereas the populations of three other (group II) species did not crash. In stepwise multiple regressions between per-capita growth rate, r , and four winter temperatures, population size and year, population size was selected in all species. Winter temperatures were selected only in robin and wren. The residual variation of r which remained after the selected variables were used in a multiple regression equation was randomly distributed around zero in the three group II species. In the robin and wren, however, the residual values for the years following the cold winter were significantly higher compared to those in the years before it. This suggests that something changed either in the environment or in the birds. Robin residuals after the cold winter returned towards zero, whereas wren residuals remained at the new high level. I argue that these results can best be explained through assuming that catastrophic winter mortality was non-random and could have caused micro-evolutionary changes in life-history traits.     

Historic and contemporary levels of genetic variation in two New Zealand passerines with different histories of decline

We compared historic and contemporary genetic variation in two threatened New Zealand birds (saddlebacks and robins) with disparate bottleneck histories. Saddlebacks showed massive loss of genetic variation when extirpated from the mainland, but no significant loss of variation following a severe bottleneck in the 1960s when the last population was reduced from approximately 1000 to 36 birds. Low genetic variation was probably characteristic of this isolated island population: considerably more genetic variation would exist in saddlebacks today if a mainland population had survived. In contrast to saddlebacks, contemporary robin populations showed only a small decrease in genetic variation compared with historical populations. Genetic variation in robins was probably maintained because of their superior ability to disperse and coexist with introduced predators. These results demonstrate that contemporary genetic variation may depend more greatly on the nature of the source population and its genetic past than it does on recent bottlenecks.     

Winter segregation of migrant European robins Erithacus rubecula in relation to sex, age and size

Birds often show some form of social segregation during winter, both at large geographical scales (a consequence of differential migration) and at the regional or local level, when comparing different habitats or micro-habitats. However, our understanding of the mechanisms underlying such patterns is still poor. These issues have been rarely investigated in migratory Old-World passerines, particularly with respect to differences between the sexes. In this study, we show that female European robins Erithacus rubecula (sexed by molecular techniques) greatly outnumber males in southern Iberia, which confirms that this species is a differential migrant with a strong latitudinal segregation of the sexes. Furthermore, sex, age and body size influence the habitat distribution of robins in winter. Subordinate birds (females, juveniles and small individuals) were generally more common in habitats with a greater shrub development, and comparatively scarce in woodlands with relatively little undergrowth. Birds wintering in woodlands were in better condition (assessed by breast-muscle scoring) than birds wintering in shrubland. These results are consistent with the hypothesis that proposes that social dominance, mediated by differences in size and experience, is important in determining the habitat segregation of sex and age classes. The alternative hypothesis (habitat specialization), although not specifically supported by our findings, cannot be ruled out on the basis of the available evidence.     

The relative importance of conditions in wintering and passage areas on spring arrival dates: the case of long-distance Iberian migrants

Remote sensing data have been used in previous studies to assess the effects of winter ecological conditions in Africa on biological parameters recorded in bird populations during the following breeding season in Europe. Based on the results of these studies, we hypothesized that a high productivity of vegetation during the winter and, thus, high resource availability, should advance the arrival of long-distance migrants to the European breeding areas due to enhanced ecological conditions. To test this hypothesis, between 1982 and 2000 we examined the first arrival date to the Iberian Peninsula of five species (White Stork, Cuckoo, Common Swift, Barn Swallow and Nightingale) in relation to several explanatory variables: ecological conditions in their African wintering grounds and passage areas, as reflected by the normalized difference vegetation index (NDVI), temperature and precipitation in their passage areas and the winter North Atlantic Oscillation (NAO). Ecological conditions in the wintering areas were important for White Stork, Cuckoo and Barn Swallow phenology, while both NDVI in passage areas and NAO did not have an effect on any species. Migratory birds arrived earlier after winters with high vegetation productivity in Africa. Temperature in passage areas was important for the later species (i.e. Cuckoo, Common Swift and Nightingale), although in all cases the true relevance of this factor was scarce due to the poor explanatory capacity of the models. These species were recorded in the Iberian Peninsula earlier in the spring of those years with warmer temperatures in passage areas. The nexus between African NDVI and arrival phenology is hypothesized through increases in wintering survival rates and/or the faster acquisition of pre-migratory body condition and progression through sub-Saharan areas. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Losing anti‐predatory behaviour: A cost of translocation

Translocation of endangered species to habitats where exotic predators have been removed is now a common conservation practice around the world. Many of these translocated populations have thrived, and they are often used as sources for the harvesting of individuals for translocations to sites where exotic predators still exist, albeit at reduced densities. This study investigates how isolation from exotic predators affects the ability of individuals to recognize such predators using the North Island robin (Petroica longipes) as a model. The study was carried out in three robin populations in the North Island, New Zealand: a translocated population on Tiritiri Matangi Island, where exotic mammalian predators are absent; a population reintroduced from Tiritiri Matangi Island to Wenderholm Regional Park, a mainland site where these mammals are controlled to low densities; and a mainland population at Benneydale where exotic predatory mammals are common. The response intensity of robins to a model stoat was high at Benneydale and low at Tiritiri Matangi and Wenderholm. This result indicates that isolation from mammalian predators on Tiritiri Matangi has suppressed the ability of North Island robins to recognize these predators. It is possible that the low predatory mammal densities at Wenderholm have reduced robin contact with stoats, therefore reduced the opportunity for robins to learn to recognize stoats. Thus, translocation of individuals from populations without predators to places where key predators still exist could be unsuccessful if translocated individuals fail to perform appropriate anti‐predator behaviours.