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Longevity and survival of the Endangered Seychelles Magpie Robin Copsychus sechellarum


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The Seychelles Magpie Robin Copsychus sechellarum was once one of the most threatened birds in the world, but was downgraded from Critically Endangered to Endangered after a long-term recovery programme was success- fully implemented. Comprehensive long-term monitoring of this species was conducted on the islands of Cousin and Cousine over an 18-year period. We report here on the species longevity and annual survival at these two sites. The oldest recorded individual was a male who died on Cousine Island on 28 September 2000 at just under 16 years old. This individual was recorded to have hatched on Frégate Island on 3 January 1985, before being translocated to Cousine Island in 1995. Mean annual survival rates over an 18-year period were 81.6% on Cousin and 77.9% on Cousine islands. A decrease in annual survival was noted with increasing population size on both islands (Cousin: t = −3.09, p < 0.05; Cousine: t = −2.71, p < 0.05), which is a likely consequence of increased territory disputes and competition for food.
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Journal of African Ornithology
ISSN: 0030-6525 (Print) 1727-947X (Online) Journal homepage:
Longevity and survival of the Endangered
Seychelles Magpie Robin Copsychus sechellarum
Julie Gane & April Burt
To cite this article: Julie Gane & April Burt (2016) Longevity and survival of the Endangered
Seychelles Magpie Robin Copsychus sechellarum, Ostrich, 87:1, 81-83
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Ostrich 2016, 87(1): 81–83
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ISSN 0030–6525 EISSN 1727-947X
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Short Note
Longevity and survival of the Endangered Seychelles Magpie Robin
Copsychus sechellarum
Julie Gane1* and April Burt2
1 Cousine Island, PO Box 977, Victoria, Mahé, Seychelles
2 Nature Seychelles, Roche Caiman, Mahé, Seychelles
* Corresponding author, email:
The Seychelles Magpie Robin Copsychus sechellarum was once one of the most threatened birds in the world, but
was downgraded from Critically Endangered to Endangered after a long-term recovery programme was success-
fully implemented. Comprehensive long-term monitoring of this species was conducted on the islands of Cousin
and Cousine over an 18-year period. We report here on the species longevity and annual survival at these two sites.
The oldest recorded individual was a male who died on Cousine Island on 28 September 2000 at just under 16 years
old. This individual was recorded to have hatched on Frégate Island on 3 January 1985, before being translocated
to Cousine Island in 1995. Mean annual survival rates over an 18-year period were 81.6% on Cousin and 77.9% on
Cousine islands. A decrease in annual survival was noted with increasing population size on both islands (Cousin:
t = −3.09, p < 0.05; Cousine: t = −2.71, p < 0.05), which is a likely consequence of increased territory disputes and
competition for food.
Keywords: annual survival, Copsychus sechellarum, Cousin Island, Cousine Island, longevity, Seychelles Magpie Robin
The Seychelles Magpie Robin Copsychus sechellarum
(SMR) is endemic to the Seychelles Archipelago in
the Indian Ocean (López-Sepulcre et al. 2008). It is a
passerine bird that forms small social groups comprised
of a dominant pair and up to eight subordinate individuals
(López-Sepulcre et al. 2008). Each social group defends a
common territory on which they rely for their nesting sites,
foraging areas and water provisions (McCulloch 1996;
López-Sepulcre et al. 2008). Each territory varies in quality
and size causing individuals and social groups to compete
for and extend existing territories into higher quality habitat
areas (López-Sepulcre et al. 2010). Habitat loss and
predator introduction occurred after human settlement in
1770 and were responsible for the dramatic decrease in
population numbers, consequently resulting in the extinction
of the species from seven of only eight originally occupied
islands (Komdeur 1996). In 1990 a total of 23 individuals
remained on Frégate Island (201 ha) alone. This prompted
BirdLife International and the Royal Society for the
Protection of Birds to initiate a recovery programme in 1990
(Norris and McCulloch 2003; López-Sepulcre et al. 2008),
which was later taken over by Nature Seychelles in 1998.
Nature Seychelles set up and facilitated a local stakeholder
group, the Seychelles Magpie Robin Recovery Team
(SMART), to assist in decision-making and management.
BirdLife International successfully translocated individ-
uals from Frégate Island to the islands of Cousin in 1994
and Cousine in 1995. Nature Seychelles led the transloca-
tions to Aride in 2002 and Denis in 2008 (López-Sepulcre
et al. 2008; Gerlach and Le Maitre 2009). Due to the
conservation efforts to increase the overall population, the
International Union for the Conservation of Nature changed
the status of the SMR from Critically Endangered to
Endangered in 2005 (López-Sepulcre et al. 2009). Despite
this conservation success little is known about the longevity
and annual survival of this species. Individual SMRs are
believed to be long-lived (Komdeur 1996), but no analysis
of long-term data has been undertaken.
For this study we considered data from the islands of
Cousin (04°33′14″ S, 55°66′31″ E) (27 ha) and Cousine
(04°21′41″ S, 55°38′51″ E) (26 ha), for which reliable and
consistent data have been collected for 18 years. Cousin
and Cousine support an average of 49 and 32 individual
SMRs, respectively. Since translocation to both islands
the SMR populations have been monitored closely on
a daily (sightings), weekly (behavior and breeding) and
monthly (movement) basis. All chicks were ringed prior
to or shortly after fledging. Each individual wears a metal
South African Bird Ringing Unit (SAFRING) and an island-
specific colour ring, allowing for early identification of birds
that have migrated from another island. The second leg
holds two colour rings, the combination of which is unique
to that individual allowing for ease of population monitoring.
Individuals were identified from several metres away by
sight or by further using binoculars. Each individual bird
was located and recorded at least once monthly but in
most cases weekly, providing rigorous mark and ‘recapture’
data. A summary of activity was made and individuals that
were not seen during that particular month were noted as
missing; if they disappeared for three consecutive months
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Gane and Burt
they were assumed dead and removed from the island
population list. This assumption of death was valid due to
there being no record of missing individuals re-emerging
once removed from the respective islands population list.
Since 1994 there have been a total of seven confirmed
inter-island movements/migrations, six of which involved
movement either to or from Cousine or Cousin. The
nature of the monitoring of SMR on each island makes it
extremely unlikely that a migrated bird would go unnoticed
and therefore these figures can be considered robust and
hence migration of birds can be considered a negligible
factor when calculating annual survival. All breeding
attempts were monitored and all individuals have recorded
life histories from hatching to death. Longevity results were
taken from when the individuals hatched to when they died
or went missing (assumed dead), or if they were still living
the age is accurate until June 2014. Annual survival was
calculated using the same method as Watson et al. (1992)
as the percentage of marked adult birds present in year Y
and detected in Y + 1 (juveniles added after one year).
For each year Y there was replenishment of the number of
marked birds.
Since translocation to present, a total of 201 individuals
have resided on Cousin and 143 individuals on Cousine.
Longevity was determined using this data set of 344
individuals over an 18-year period. A total of 11 (3.2%)
individuals from both Cousin and Cousine surpassed a
10-year survival period. The oldest recorded individual was
a male who died on Cousine Island on 28 September 2000
at just under 16 years old. This individual was recorded to
have hatched on Frégate Island on 3 January 1985 and
was translocated to Cousine Island in 1995. The mean
age at death on both islands is 3 (SD 2.6) years old, with
no significant difference between the sexes (two-sample
t-test: t = −1.257, df = 46, p = 0.947). Annual survival
rates over this 18-year period were recorded as 81.6%
on Cousin and 77.9% on Cousine (Figure 1). Both islands
showed a significant relationship in annual survivorship with
population increase (linear regression; Cousin b = −0.348,
t = −3.09, p < 0.05, df = 18; Cousine: b = −0.639, t = −2.71,
p < 0.05, df = 17). No significant difference was found in
annual survival between the islands overall (two-sample
t-test: t = 0.869, df = 17, p = 0.397).
Watson et al. (1992) reported on the low reproductive
rate for this species with an average 1.1 chicks per pair
annually and reproductive maturity being reached by
12–14 months. In addition, only the dominant pair in each
territory breed. With populations fully saturated on Cousin
and Cousine there are 10–11 and 7–9 territories, respec-
tively, and therefore population recruitment is restricted to
and dependent on 10–11 and 7–9 breeding pairs, respec-
tively. The long lifespan that is here recorded is a likely
benefit to population survival and growth of this species;
by having the same dominant breeder for several years
the number of disputes within territorial groups is likely
reduced. There also appears to be an increase in reproduc-
tive output with age once a breeding pair is established
(unpublished data), which would suggest that there is
an optimum breeding age, though further study here
is required. Longevity of the SMR is of further interest
considering its endangered status and its recent history
involving several translocations. By understanding the
lifespan we are better able to make conservation manage-
ment plans for this species, such as improving output by
removing unproductive, older dominant individuals to
alternative territories or by ensuring the successful translo-
cation and establishment of a population by selecting the
most favourable individuals according to life stage. All
applications of management are aimed at improving the
conservation status from Endangered to Threatened. The
thorough data collected on this species on both Cousin
and Cousine since translocation has provided long-term
insight into the species annual survival. Both islands
demonstrate similar levels of annual survival with no signifi-
cant difference found overall (t = 0.869, df = 17, p = 0.397).
Most notably, an overall decrease in annual survival
overtime on both islands was linked to population increase.
It has been reported that aggressive defense of territorial
Figure 1: Significant linear regression of Seychelles Magpie Robin annual survival and population size with associated R2 values for Cousin
and Cousine Islands, Seychelles
² = 0.3601
² = 0.3529
10 20 30 40
Linear (Cousin)
Linear (Cousine)
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Ostrich 2016, 87(1): 81–83
boundaries operate as a limiting factor within populations
of this species (Watson et al. 1992), likewise density-
dependent effects on reproduction can also be caused by
competition for food as recorded for the Seychelles Warbler
Acrocephalus sechellensis (Brouwer et al. 2009). It is likely
that both increased territory disputes and competition for
food are limiting factors for this species’ population growth,
particularly given its geographic constraints.
Acknowledgements We would like to thank all personnel who
have contributed to SMR data collection over the years. The data
used for this report were taken from the SMART databases for both
Islands; the monitoring of this species has been the combined effort
of many personnel over the years. We would also like to thank
Drs Lorinda Hart, Mark Brown and Nirmal Shah for their expertise
and guidance in producing this paper. Thanks to Nature Seychelles
and Cousine Island management for financially supporting our
work. We would also like to thank the three anonymous reviewers
for recommendations to improve this manuscript.
Brouwer L, Richardson DS, Eikenaar C, Komdeur J. 2009.
Experimental evidence for density-dependent reproduction in a
cooperatively breeding passerine. Ecology 90: 729֪–741.
Gerlach J, Le Maitre S. 2009. Sex ratio variation in small island
populations of an endangered bird, the Seychelles Magpie
Robin, Copsychus sechellarum. Ostrich 72: 114–117.
Komdeur J. 1996. Breeding of the Seychelles Magpie Robin
Copsychus sechellarum and implications for its conservation. Ibis
138: 485–498.
López-Sepulcre A, Doak N, Norris K, Shah N. 2008. Population
trends of Seychelles magpie-robins Copsychus sechellarum
following translocation to Cousin Island, Seychelles. Conservation
Evidence 5: 33–37.
López-Sepulcre A, Kokko H, Norris K. 2010. Evolutionary conser-
vation advice for despotic populations: habitat heterogeneity
favours conflict and reduces productivity in Seychelles magpie
robins. Proceedings of the Royal Society B 277: 3477–3482.
López-Sepulcre A, Norris K, Kokko H. 2009. Reproductive conflict
delays the recovery of an endangered social species. Journal of
Animal Ecology 78: 219–225.
Norris K, McCulloch N. 2003. Demographic models and the
management of endangered species: a case study of the
critically endangered SMR. Journal of Applied Ecology 40:
Watson J, Warman C, Todd D, Laboudallon V. 1992. The
Seychelles magpie robin Copsychus sechellarum: ecology and
conservation of an endangered species. Biological Conservation
61: 93–106.
Received 18 October 2014, revised 9 March 2015, accepted 21 March 2015
Associate Editor: Richard Sherley
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... Critical habitat requirements for the Magpie-robin are specifically bare earth and leaf litter occurring under mature shady woodland (Watson et al. 1992 ). Magpie-robins form small social groups comprised of a dominant pair and a number of subordinates, varying from one to eight and living to a maximum of 15 years (Gane and Burt 2016 ). Each social group defends a common territory that they rely on for nesting sites, foraging areas and water (López-Sepulcre et al. 2008, McCulloch 1996. ...
... In general a minimum of one migrant per generation is sufficient to minimise the loss of polymorphism and heterozygosity within subpopulations while allowing for divergence in allele frequencies among subpopulations (Mills and Allendorf 1996 ). With the average lifespan of Magpie-robin being 2.6 years old, and longest lived 15 years old (Gane and Burt 2016 ), it is likely that the Cousin/Cousine Magpie-robins could be considered one population, based on inter-island movements, whereas Frégate, Aride and Denis are isolated populations. Further studies are required to investigate this. ...
Full-text available
The once ‘Critically Endangered’ Seychelles Magpie-robin was down to just 12 individuals in 1960 on one island of the granitic Seychelles. In 2015, due to intensive long-term management the population stands at around 280 birds on five islands, marking a significant success for this species. Translocations to the islands of Cousin and Cousine have led to population saturation and stability, a translocation to Denis Island has resulted in a continuing population increase and the founder population on Frégate Island is likewise increasing. The latest translocation to Aride Island in 2002 resulted in population increase then stability but is now showing a steep decline throughout 2014 into 2015. Reasons for this decline are yet unknown though disease, lack of recruitment, the impacts of social conflict and the possibility of genetic issues are discussed. This report summarises the history of management for this species, compiling all available published and unpublished information, to provide a comprehensive account of the Seychelles Magpie-robin recovery.
... Cousine Island (~26 ha) is one of the smallest granitic islands in the Seychelles Archipelago, at just over 1 km long and 400 m wide, and its highest elevation is 70 m (Samways et al. 2010). The island is privately owned and is run primarily as a conservation island (Gane and Burt 2016). The single beach on the island is ~900 m in length and supports an average of 70-130 hawksbill turtle nests each nesting season (Hitchens et al. 2004). ...
Sea turtle populations have declined globally and are of conservation concern. We investigated the effects of nest management methods on hatching success and egg/hatchling predation rates of hawksbill turtles Eretmochelys imbricata on Cousine Island, Seychelles. We determined the effectiveness of two different crab-barrier methods (netted and fenced) on hatching success and predation rates. We examined the relative influence of nest-site cover (full sun, partial sun or full shade) and location (zones of high risk or low risk of predation) on hatching success and predation rates. We also examined temperature disparity between netted and control nests to estimate potential effects on sex ratios and measured typical beach-substrate temperatures in the different nesting habitats. We compared data from 40 netted, 40 fenced and 40 control nests during the 2014/2015 breeding season. Overall, hawksbill turtle hatching success was not significantly affected by treatment or cover; however, netted nests and nests incubating in full sun had the highest mean hatching success. Predation rate was generally low but variable, and the rates differed significantly between the three treatments. Nest temperatures differed significantly between the netted and control nests, with netting used to protect nests having a substantial cooling effect. Hatchling sex ratios for natural nests were skewed towards females and those for netted nests skewed towards males. With climate change and increasing ambient temperatures imminent, a better understanding of how the spatial distribution of nests and variations in environmental factors influence hawksbill turtle hatching success and the levels of predation on eggs and hatchlings will assist future conservation measures.
Habitat loss and degradation are currently the main anthropogenic causes of species extinctions. The root cause is human overpopulation. This unique volume provides, for the very first time, a comprehensive overview of all threatened and recently extinct mammals, birds, reptiles, amphibians, and fishes within the context of their locations and habitats. The approach takes a systematic examination of each biogeographic realm and region of the world, both terrestrial and marine, but with a particular emphasis on geographic features such as mountains, islands, and coral reefs. It reveals patterns useful in biodiversity conservation, helps to put it all into perspective, and ultimately serves as both a baseline from which to compare subsequent developments as well as a standardization of the way threatened species are studied.
Populations of the Critically Endangered hawksbill turtle Eretmochelys imbricata in the Seychelles showed significant declines in the past. They have since recovered and nesting numbers are increasing because of increased protection and management intervention. Data on their nesting ecology on Cousine Island were collected and analysed for the breeding seasons from 2004/2005 to 2013/2014 with the aim of improving management methods. The findings indicate that the number of nesting individuals increased during the study period (from x̅ = 34.3 nesters between 2004 and 2009, to x̅ = 55.4 nesters between 2010 and 2014); however, the clutch frequency was relatively low compared with other study areas. Night-time nesting increased, most likely because of increased disturbances across the study period. Clutch sizes decreased significantly across the nesting season, and there was a significant drop in hatching success in clutch sizes exceeding 200 eggs. The predation rate and infertility rate each showed an increasing trend over time. Nests incubating in full sun showed the highest mean hatching success rate and had the shortest mean incubation duration. The present study provides insight into the species’ nesting ecology on Cousine Island and will better inform management decisions aimed at increasing hatching success and minimising threats such as beach erosion and predation.
Full-text available
We report on the translocation of Seychelles magpie-robins Copsychus sechellarum, from the island of Frégate to the island of Cousin between 1994 and 1995. Prior to this translocation, the world population consisted of 47 individuals confined to Frégate. Five magpie-robins were translocated to Cousin and subsequently a new self-sustaining breeding population was established; this population increased almost 10-fold in less than 12 years to a high of 46 individuals in May 2006. It is now currently experiencing signs of regulation with a slight decrease in numbers with 31 birds recorded in June 2007. It is hoped that ongoing studies will identify the reasons for this decline, which at present are unclear.
Full-text available
Individual preferences for good habitat are often thought to have a beneficial stabilizing effect for populations. However, if individuals preferentially compete for better-quality territories, these may become hotspots of conflict. We show that, in an endangered species, this process decreases the productivity of favoured territories to the extent that differences in productivity between territories disappear. Unlike predictions from current demographic theory on site-dependent population regulation (ideal despotic distribution), we show that population productivity is reduced if resources are distributed unevenly in space. Competition for high-quality habitat can thus have detrimental consequences for populations even though it benefits individuals. Manipulating conflict (e.g. by reducing variation in habitat quality) can therefore prove an effective conservation measure in species with strong social or territorial conflict.
The total population of the Seychelles Magpie Robin Copsychus sechellarum declined from 38–41 birds in 12–13 territories in 1977–1978 to 17–21 birds in eight to nine territories in 1988–1990 and was entirely confined to Fregate Island (210 ha) in the Seychelles. After a successful cat eradication program in 1981–1982, recruitment improved, although the abandonment of agriculture had caused a reduction in the amount of feeding habitat and hence in the carrying capacity of the island. The population declined because of the failure of recruitment to compensate for the annual adult mortality. Foraging activity of the Magpie Robin was greater in high-quality territories (measured by soil invertebrates available), leading to increased reproductive success. Through supplementary feeding, five times as many recruits were produced. Of the 11.5 potential annual breeding recruits, 5.3 are required to compensate for adult mortality, and the other 6.2 recruits can be regarded as “surplus” contributing to an increase. Magpie Robins prefer to breed in rotten trees, which are a scarce resource. The greater the distance between the nest site and feeding areas, the less time was spent in incubation and nest guarding, resulting in greater egg loss. Because of lack of suitable areas for establishing territories, many young Magpie Robins became “floaters”. Nest disturbance, both by these floaters and by the introduced Indian Mynah Acridotheres tristis, had adverse effects on the breeding success of robins. A recovery plan has been designed to save the Magpie Robin. Territories have been improved for feeding (by tree planting) and for breeding (by providing nestboxes and reducing nest disturbances). Given the vulnerability of one small island, the presence of surplus birds (supported mainly by supplementary food) and the suitability of neighbouring Aride Island (68 ha), successful translocations to this island took place in 1992 and 1994. Given the presence now of 47 individuals on two islands, it is hoped that the species will pull back from the brink of extinction.
Demographic models are assuming an important role in management decisions for endangered species. Elasticity analysis and scope for management analysis are two such applications. Elasticity analysis determines the vital rates that have the greatest impact on population growth. Scope for management analysis examines the effects that feasible management might have on vital rates and population growth. Both methods target management in an attempt to maximize population growth. The Seychelles magpie robin Copsychus sechellarum is a critically endangered island endemic, the population of which underwent significant growth in the early 1990s following the implementation of a recovery programme. We examined how the formal use of elasticity and scope for management analyses might have shaped management in the recovery programme, and assessed their effectiveness by comparison with the actual population growth achieved. The magpie robin population doubled from about 25 birds in 1990 to more than 50 by 1995. A simple two‐stage demographic model showed that this growth was driven primarily by a significant increase in the annual survival probability of first‐year birds and an increase in the birth rate. Neither the annual survival probability of adults nor the probability of a female breeding at age 1 changed significantly over time. Elasticity analysis showed that the annual survival probability of adults had the greatest impact on population growth. There was some scope to use management to increase survival, but because survival rates were already high (> 0·9) this had a negligible effect on population growth. Scope for management analysis showed that significant population growth could have been achieved by targeting management measures at the birth rate and survival probability of first‐year birds, although predicted growth rates were lower than those achieved by the recovery programme when all management measures were in place (i.e. 1992–95). Synthesis and applications. We argue that scope for management analysis can provide a useful basis for management but will inevitably be limited to some extent by a lack of data, as our study shows. This means that identifying perceived ecological problems and designing management to alleviate them must be an important component of endangered species management. The corollary of this is that it will not be possible or wise to consider only management options for which there is a demonstrable ecological benefit. Given these constraints, we see little role for elasticity analysis because, when data are available, a scope for management analysis will always be of greater practical value and, when data are lacking, precautionary management demands that as many perceived ecological problems as possible are tackled.
In 1977–1978 some 40 Seychelles magpie robins Copsychus sechellarum, the entire world population, survived on Frégate island. These lived in 12 territorial groups of up to six individuals. Their range on Frégate was limited by the amount of feeding habitat, specifically bare earth and leaf litter which occurred under mature shady woodland and in cultivated vegetable gardens. Two attempts were made to reintroduce the species to Aride Island in 1978 and 1979. These were unsuccessful and the translocations had to be abandoned when a new threat impinged on the parent population of Frégate in 1980. By 1981 numbers there had declined to 18, with virtually no recruitment, and an increase in the feral cat population was implicated. A successful cat eradication programme by trapping and poisoning was carried out in 1981–1982. By 1983–1984 the population showed a recovery with recruitment again healthy, although the abandonment of agriculture on Frégate between 1979 and 1983 had caused a reduction in the amount of feeding habitat and in the carrying capacity of the island to around 25 individuals in eight territorial groups. A range of management options is discussed.
Temporal variation in survival, fecundity, and dispersal rates is associated with density-dependent and density-independent processes. Stable natural populations are expected to be regulated by density-dependent factors. However, detecting this by investigating natural variation in density is difficult because density-dependent and independent factors affecting population dynamics may covary. Therefore, experiments are needed to assess the density dependence of demographic rates. In this study, we investigate the effect of density on demographic rates of the Seychelles Warbler (Acrocephalus sechellensis). This species, endemic to a few islands in the Indian Ocean, went through a severe population bottleneck in the middle of the last century, with only approximately 30 individuals left on one small island, but has since recovered. Our monitoring shows that since reaching the island's carrying capacity, population density has remained stable. However, we detected neither density-dependent reproduction nor survival on the basis of natural density variation during this stable period. For conservation reasons, new populations have been established by transferring birds to nearby suitable islands. Using the change of numbers during the process of saturation as a natural experiment, we investigated whether we can detect regulation of numbers via density-dependent survival and reproduction within these new populations. We found that populations were mainly regulated by density-dependent reproduction, and not survival. Variation in density between islands can be explained by food abundance, measured as insect density. Islands with the highest insect densities also had the highest bird densities and the largest breeding groups. Consequently, we suggest that the density-dependent effect on reproduction is caused by competition for food.
1. Evolutionary theory predicts that individuals, in order to increase their relative fitness, can evolve behaviours that are detrimental for the group or population. This mismatch is particularly visible in social organisms. Despite its potential to affect the population dynamics of social animals, this principle has not yet been applied to real-life conservation. 2. Social group structure has been argued to stabilize population dynamics due to the buffering effects of nonreproducing subordinates. However, competition for breeding positions in such species can also interfere with the reproduction of breeding pairs. 3. Seychelles magpie robins, Copsychus sechellarum, live in social groups where subordinate individuals do not breed. Analysis of long-term individual-based data and short-term behavioural observations show that subordinates increase the territorial takeover frequency of established breeders. Such takeovers delay offspring production and decrease territory productivity. 4. Individual-based simulations of the Seychelles magpie robin population parameterized with the long-term data show that this process has significantly postponed the recovery of the species from the Critically Endangered status. 5. Social conflict thus can extend the period of high extinction risk, which we show to have population consequences that should be taken into account in management programmes. This is the first quantitative assessment of the effects of social conflict on conservation.