Showing papers in "Ostrich in 2017"
TL;DR: In this article, a survey of the current status of the Hooded Vulture in the Lower Casamance region of Senegal, in the Western Region of The Gambia and in Guinea-Bissau is presented.
Abstract: As in many West African cities, in Dakar Hooded Vultures Necrosyrtes monachus have always been characteristic urban scavengers. The recent decline of Hooded Vultures in other parts of Africa, mainly eastern Africa, has been the reason in 2015 for up-listing of its status by the IUCN in the Red List of Threatened Species to Critically Endangered. As the Hooded Vulture is still common in the Lower Casamance, Senegal, in the Western Region of The Gambia and in Guinea-Bissau, without clear signs of a recent decrease, a survey of its current status in Dakar was undertaken and compared with historical data over the past 50 years. A strong decrease of >85% was noted from 3 000 individuals in 1969 to 400 in 2016. This decline is on the high end of the decline noticed over much of its range but in striking contrast with the apparently stable populations along the West African coast more to the south (The Gambia to Guinea). Likely causes are (1) exponential urbanisation resulting in loss of feeding sites and reduce...
27 citations
TL;DR: This study demonstrated the ability of camera trapping to produce accurate, reliable and rapid species inventories within palustrine wetland habitats and clearly display that camera trapping as a non-invasive survey technique can effectively determine and monitor arguably the most cryptic and elusive of the Rallidae genera within southern Africa.
Abstract: Wetlands are vital habitats for a variety of organisms and ecosystem services, but the health of these valuable habitats is declining worldwide. The Rallidae species that rely on these habitats are typically elusive, cryptic and difficult to monitor accurately, especially in dense wetland vegetation. To date, invasive survey techniques such as rope dragging have largely been applied in surveying species within these genera. A survey of palustrine wetland habitat using camera traps was implemented to ascertain the efficacy of this non-invasive monitoring technique for surveying elusive wetland avian species. The survey yielded a total of 445 independent sightings across 15 target wetland species, including four Rallidae species. Our results clearly display that camera trapping as a non-invasive survey technique can effectively determine the presence and monitor arguably the most cryptic and elusive of the Rallidae genera within southern Africa. In addition, data sets produced through this survey technique ...
18 citations
TL;DR: Escape behaviour in response to perceived predators can be employed as a guide when designating protected areas around sensitive bird species to minimise the impact of human disturbance as discussed by the authors, which can be used as a way to identify the most vulnerable birds.
Abstract: Escape behaviour in response to perceived predators can be employed as a guide when designating protected areas around sensitive bird species to minimise the impact of human disturbance. A key meas...
18 citations
TL;DR: This paper reviewed all the published literature on the Web of Science classified as "ornithology" with an accompanying keyword of a country's name, over the last three decades, from the 16 countries within West Africa and compared it with that from 16 Western European countries.
Abstract: West Africa has high bird diversity and is a crucial non-breeding area for over one-third of European breeding species, yet local capacity for ornithological research and so targeted bird conservation is perceived to be limited. I reviewed all the published literature on the Web of Science™ classified as ‘ornithology’ with an accompanying keyword of a country’s name, over the last three decades, from the 16 countries within West Africa and compared it with that from 16 Western European countries. Inclusion of the country’s name as a search term identified any papers produced by local authors, and so should provide an index of local ornithological capacity. Overall only 129 papers were produced from 1987 to 2016 with West African authors (range: zero Burkina Faso to 45 Nigeria), significantly fewer compared with 12 380 with European authors (range: 71 Greece to 2 745 England). The number of papers produced increased significantly at similar rates over the three-decade period in both continents. The number of papers produced by local authors in West Africa and Europe approximately doubled each decade, but variation between countries was large, particularly in West Africa. The results are broadly the same when paper output is adjusted for the population of each country. Of the three West African countries that showed a consistent increase in numbers of locally authored ornithological papers, only Nigeria showed a highly significant increase and this increase was down to a single ornithological research institute established there in 2002. The results confirm that there is little local ornithological capacity in West Africa and this is not changing except in Nigeria, where even a single new research institute can make a significant difference because of the very low baseline.
17 citations
TL;DR: It is estimated that oil palm fruits account for almost 50% of the assimilated diet, followed by fish, crabs and Green Turtle hatchlings or eggs, as revealed by stable isotopes and Bayesian mixing models.
Abstract: Populations of many vulture species have undergone substantial declines. In Africa, 82% are threatened and although research on vultures has increased, the biology and ecology of several species is still poorly known. The Palm-nut Vulture Gypohierax angolensis has peculiar ecological characteristics, feeding on palm fruits, associated with the aquatic environment and taking a wide variety of prey. It has been over 40 years since the last thorough study on the ecology of the species was undertaken. This study investigated several ecological and behavioural aspects of Palm-nut Vultures, using a combination of direct observations, stable isotope analysis and Bayesian mixing models. The population of this species within the Joao Vieira and Poilao Marine National Park is estimated to be 21–30 birds km−2. Egg laying started in November (early dry season) and some chicks were still growing in early May. A minimum of 54% of nests produced a fledgling. Observations suggest that Palm-nut Vultures moult all flight f...
14 citations
TL;DR: Marabou Storks Leptoptilos crumeniferus have become common in many urban centres, including Kampala, Uganda, where, as of 2016, they number several thousand birds, with more than 1 200 breeding pairs Elsewhere in Uganda, the majority of colonies are also in towns and villages as discussed by the authors.
Abstract: In recent decades, Marabou Storks Leptoptilos crumeniferus have become common in many urban centres, including Kampala, Uganda, where, as of 2016, they number several thousand birds, with more than 1 200 breeding pairs Elsewhere in Uganda, the majority of colonies are also in towns and villages Traditionally, a bird of savannas, breeding in those areas is timed so that the growing young are in the nest during the December to February drier period, when food for scavengers is expected to be more abundant In southern Uganda, most colonies start each season around November, and this was originally the case in Kampala However, in recent years, nesting has begun several weeks earlier for the majority of pairs, and up to four months earlier for a smaller group The main diet of Marabous in Kampala is human refuse, which is available all year round, so in principle they could nest at any time However, they do not do that In ‘natural’ ecosystems, breeding at the ‘wrong’ time would probably be disadvantageou
14 citations
TL;DR: The diet composition of breeding Black Harriers is studied to confirm that this species can be considered a small mammal specialist and reveal the importance of birds and reptiles as alternative prey, particularly in inland regions, and show inter-annual variations in diet in both regions.
Abstract: Studying the diet of wild animals is central for understanding their flexibility in food requirements. The Black Harrier Circus maurus is an endangered raptor in South Africa and Namibia. To date, information about the diet of the species is insufficient for a comprehensive understanding of its ecology. We studied the diet composition of breeding Black Harriers using c. 1 000 pellets (>1 700 identified prey) collected at nest sites in two geographical regions (coastal vs inland) over 10 breeding seasons (2006–2015). We show the importance of small mammals in Black Harrier diet (64.4% and 78.2% of prey and consumed biomass, respectively), with the four-striped mouse Rhabdomys pumilio being a main trophic resource. We also reveal the importance of birds and reptiles as alternative prey, particularly in inland regions, and show inter-annual variations in diet in both regions. Our study confirms that this species can be considered a small mammal specialist. Specialist predators are more vulnerable than genera...
13 citations
TL;DR: Hooded Vultures Necrosyrtes monachus are critically endangered but little is known of their year-round use of nests or whether other species usurp Hooded Vulture nest sites, so the nest monitoring programme is recommended to include more pairs.
Abstract: Hooded Vultures Necrosyrtes monachus are critically endangered but little is known of their year-round use of nests or whether other species usurp Hooded Vulture nest sites. We investigated visitation rates by Hooded Vultures and other species (including potential nest predators and usurpers) to examine their effect on Hooded Vulture breeding success. We present observations of 33 species recorded by camera traps at 12 Hooded Vulture nests over a total of 93 nest-months (2 095 nest-days). Several pairs of Hooded Vultures visited their nests regularly during the non-breeding season, some adding nesting material, highlighting that pairs visited their nest(s) year round. Egyptian Geese Alopochen aegyptiaca, potential usurpers of raptor nests, were present at occupied and unoccupied Hooded Vulture nests, but we recorded no usurpation of nests by Egyptian Geese and they had no impact on vulture breeding success. Hooded Vulture breeding failure was linked to two species only: camera-trap imagery recorded one ca...
13 citations
TL;DR: The highest numbers of vulture deaths were reported from the southern half of the country, with the exception of the areas just south of Etosha National Park, and poisoning was the greatest cause of reported deaths.
Abstract: Across Africa, the illegal use of poison is triggering a continent-wide scavenger crisis, with vultures suffering the most severe negative consequences. Vultures may die as indirect victims of the conflict between livestock farmers and predators, or they may be directly targeted by poachers with the aim to reduce the role of vultures as sentinels that alert authorities of poaching events. In this study, we provide novel information on vulture mortalities across the commercial farmlands of Namibia. We show that estimated mortalities of vultures due to anthropogenic causes amount to over 800 individuals over the period 2000–2015, which underscores the magnitude of the problem. The highest numbers of vulture deaths were reported from the southern half of the country, with the exception of the areas just south of Etosha National Park, and poisoning was the greatest cause of reported deaths. Aldicarb or carbofuran were the most commonly used poisons, but strychnine is still used by about one farmer out of 10. ...
13 citations
TL;DR: Foraging behaviour and substrate, i.e. whether foraging in the air, from a perch or on the ground, significantly influenced the probability that ants would be included in the diet of bird species in southern Africa.
Abstract: Ants (Hymenoptera: Formicidae) are eaten by a number of bird species in southern Africa. Our database contained 545 species (excluding waterbirds and raptors), of which 179 species have been observed feeding on ants, or had ants in their stomachs. Ants are eaten by birds in all ecosystems, but the consumption of ants is disproportionately high in species that occur in arid ecosystems. The number of bird species eating ants increases in proportion to the number of bird species in any ecosystem, but it increases disproportionately with decreasing mean annual rainfall. There was a small, but not significant, difference in the proportion of ant-eating bird species between 502 resident species, of which 154 (30.6%) eat ants, and 47 nomadic species, of which 18 (38.2%) eat ants. Foraging behaviour and substrate, i.e. whether foraging in the air, from a perch or on the ground, significantly influenced the probability that ants would be included in the diet.
12 citations
TL;DR: A model of species’ reporting rates as determined by density for this set of birds suggested the correlation between atlas reporting rates and density estimates was weak, with species capable of using modified habitats exhibiting higher reporting rates than expected from the density estimates.
Abstract: Relationships between true population densities and reporting indices from atlas data are important for the calculation of population sizes, though these relationships are remarkably little-known and likely confounded by issues of detection. We examine issues of detection for a single-observer point-count survey across the Fynbos biome in South Africa. We created an index of relative abundance comparable to atlas reporting rate and calculated detection coefficients for each species. We explore various models that explain relative abundance as a function of detection covariates, e.g. mass, colour, group size, vocal behaviour and density. Density was consistently included across models and the best predictor when used alone in a validation exercise. We then calculated mean reporting rates for the citizen science South African Bird Atlas Project2 (SABAP2). A model of species’ reporting rates as determined by density for this set of birds suggested the correlation between atlas reporting rates and density est...
TL;DR: This article conducted 1 711 km of roadside transects from mid-February to the end of May 2016, covering most of Guinea-Bissau in total 4 989 birds of 33 species were counted, of which Hooded Vultures Necrosyrtes monachus were the most common.
Abstract: Several studies have reported marked declines in populations of birds of prey across the African continent, including West Africa However, there are still regions of which virtually nothing is known, as is the case for Guinea-Bissau Because birds of prey play important roles in ecosystems and several species are threatened, it is important to establish baseline knowledge on their status This is the first study in the country focusing exclusively on birds of prey We conducted 1 711 km of roadside transects from mid-February to the end of May 2016, covering most of Guinea-Bissau In total 4 989 birds of 33 species were counted, of which Hooded Vultures Necrosyrtes monachus were the most common (252 birds per 100 km, the second highest abundance in all the species’ range) Observations outside transects, including during regular field trips throughout the country, particularly between 2012 and 2016, were used as complementary information adding 13 species to the list, and contributing three new species f
TL;DR: In this article, the authors used data from breeding territory surveys between 2000 and 2016 to estimate productivity for the southern African Bearded Vulture Gypaetus barbatus meridionalis population, and found that only around 54% ± 74% (17-91%) of pairs attempted to breed each year, and although nesting success for pairs attempting to breed was relatively high (0.75 ± 0.22; 0.44-1.00), this resulted in low productivity of only 0.42 ±0.65 ( 0.28-0.67) young
Abstract: Recent research has shown that anthropogenic influences are driving the abandonment of breeding territories in the declining southern African Bearded Vulture Gypaetus barbatus meridionalis population. Survival rates appear to be low (86% for adults) due to poisoning and collisions with powerlines, which are the primary causes of death from tracked birds. However, there is no information published on the population’s current productivity levels, and whether this may be a contributing factor in the declines of this population. This information is vital for a more holistic approach to the conservation of the population. In this study we use data from breeding territory surveys between 2000 and 2016 to estimate productivity for this population. Only around 54% ± 74% (17–91%) of pairs attempted to breed each year, and although nesting success for pairs attempting to breed was relatively high (0.75 ± 0.22; 0.44–1.00), this resulted in low productivity of only 0.42 ± 0.65 (0.28–0.67) young per pair per year. The...
TL;DR: Overall, there appeared to be a large diversity of nest adopter species for the traditional savanna living weavers (Ploceus, Bubalornis, Anaplectes, Plocepasser and Philetairus).
Abstract: Weavers build domed, long-lasting nests that may also be adopted by other species for breeding, probably reducing the energetic costs of nest building to varying degrees. In an extensive literature search, 57 species were found to have at least one record of adopting a weaver nest. There is one known obligate nest user, the Pygmy Falcon Polihierax semitorquatus. Four species were classed as near obligate nest adopters. Four species were listed as common, 10 as occasional, and 38 species as rare nest adopters. Other than the falcon and lovebirds Agapornis species, these nest adopters are passerines. Of the 57 species of nest adopters, 35 species had confirmed eggs and/or chicks found in the weaver nests. Most nest adopter species were in the Estrildidae family (20 species), with three estrildids classed as near obligates. This was followed by the Muscicapidae family, species that build cup nests. By building their cup nests inside weaver nests, there is likely protection from adverse weather and predators. Overall, there appeared to be a large diversity of nest adopter species for the traditional savanna living weavers (Ploceus, Bubalornis, Anaplectes, Plocepasser and Philetairus).
TL;DR: Egg size of the study population, which breeds at the southern limit of the species’ range, was significantly smaller than that of its northerly counterparts, suggesting that when nesting is carried out mainly on offshore floating islets, protection against aerial predators and heat stress determine nesting outcome.
Abstract: We conducted a survey of the distribution of Ferruginous Duck Aythya nyroca across Algeria and analysed the influence of nest-site characteristics on nesting success at a Ramsar site, Lake Tonga. The species was found to occupy different wetlands (freshwater lakes, brackish marshes and salt lakes) across three major climatic belts (subhumid coastal strip, semi-arid Hauts Plateaux and arid Sahara). Mean clutch size of successful nests was 13.3 ± 6.0 eggs (N = 26) with a hatching rate of 74% for successful clutches. Nesting success was recorded for 44% of nests with clutch desertion (72.7%) accounting for the majority of failed clutches. Egg size of the study population, which breeds at the southern limit of the species’ range, was significantly smaller than that of its northerly counterparts. Clutch size was negatively related to egg size and positively associated with depth of water below the nest, suggesting that older, more experienced or high-quality birds monopolised the safest sites. Successful clutc...
TL;DR: In this paper, a survey of the Principe seabird colonies was conducted in 2017 and the results revealed that the more accessible seabirds colonies have disappeared, and therefore, a long-term multi-annual monitoring is needed to understand the breeding phenology of each species and to better assess population trends.
Abstract: The Principe Autonomous Region is recognised as a marine biodiversity hotspot, although little is known about the status of its marine fauna. It holds most breeding seabirds of the tropical eastern Atlantic Ocean. Based on anecdotal accounts of increased fishing and seabird harvesting, regular monitoring of seabird populations is considered a priority. Therefore, a survey of Principe’s seabird colonies was conducted in 2017. The results revealed that the more accessible seabird colonies have disappeared. Around Principe, Bone de Joquei is the present main stronghold for Brown Boobies Sula leucogaster and White-tailed Tropicbirds Phaethon lepturus. The Tinhosas islands hold an estimated 300 000 seabirds, predominantly Sooty Terns Onychoprion fuscatus , but also Brown Boobies, Black Noddies Anous minutus and Brown Noddies Anous stolidus . Long-term multi-annual monitoring is needed to understand the breeding phenology of each species and to better assess population trends. Ensuring a protective status for both Tinhosas and the seabirds under national legislation is a key priority for future conservation policy in Sao Tome and Principe.
TL;DR: The results show that tarsus width, body mass, and DI claw (hallux) measurements are suitable for discriminating between sexes of mature Crowned Eagles, and suggest suitable parameters for accessing nests and marking nestlings.
Abstract: Although most raptor species are sexually dimorphic, many species are non-discrete in some metrics. A limited amount of existing data for southern Africa suggests that Crowned Eagles Stephanoaetus coronatus exhibit non-discrete sexual dimorphism. Consequently, we investigated gender-related morphometric data of Crowned Eagles with corresponding genetic avian sex tests. Immature (n = 13) and adult (n = 5) Crowned Eagles were trapped, measured and released in KwaZulu-Natal, South Africa from 2012 to 2015. Our results show that tarsus width, body mass, and DI claw (hallux) measurements are suitable for discriminating between sexes of mature Crowned Eagles. We comment on the use of South African Ringing Scheme (SAFRING) and colour read-rings as a marking technique in Crowned Eagles. Furthermore, we suggest suitable parameters for accessing nests and marking nestlings. To aid in the age estimates of nestling eagles, a reference of growth of known-age nestlings is provided.Keywords: African Crowned Eagle, banding, Crowned Hawk-eagle, growth, morphology, raptor, ringing, Stephanoaetus coronatus
TL;DR: In this paper, the authors investigate the effects of wintering in sub-Saharan Africa on Wood Warbler Phylloscopus sibilatrix and find that it is particularly affected.
Abstract: Populations of many Afro-Palearctic birds have declined, with those wintering in sub-Saharan Africa, such as Wood Warbler Phylloscopus sibilatrix, particularly affected. In this study we investigat...
TL;DR: Observations made during the 2014 and 2015 breeding colony censuses confirm two individuals returned to the Magaliesberg to breed and one individual successfully raised a fledgling.
Abstract: In 2010, 14 Cape Vulture Gyps coprotheres chicks were ringed as nestlings on the cliffs at the Skeerpoort Cape Vulture colony in the Magaliesberg mountains, South Africa. Observations made during the 2014 and 2015 breeding colony censuses confirm two individuals returned to the Magaliesberg to breed. One female bred at Skeerpoort while another female settled in the Nooitgedacht colony situated 25 km from her natal nest. Breeding attempts occurred at four years old for both individuals, the youngest on record for wild Cape Vultures. One individual successfully raised a fledgling.
TL;DR: Despite the negative impacts of urbanisation, some species adapt to pressures of habitat loss and fragmentation as mentioned in this paper, such as the Trumpeter Hornbills bycanistes bucinator.
Abstract: Despite the negative impacts of urbanisation, some species adapt to pressures of habitat loss and fragmentation. Trumpeter Hornbills Bycanistes bucinator are a large avian forest frugivore that use...
TL;DR: In this article, the longitudinal behavioural data of the Kalahari Meerkat Project (JBT) have been used to study the behavior of the kraar in the wild.
Abstract: This paper has relied on the longitudinal behavioural data of the Kalahari Meerkat Project, which is currently supported by the European Research Council (Research Grant no. 294494 to TCB since July 2012), the Mammal Research Institute at the University of Pretoria, and the University of Zurich. JBT is funded by a NERC Doctoral Training Program.
TL;DR: The understanding of parental care is expanded by analysing the uniparental system of Swainson’s Spurfowl Pternistis swainsonii, which releases the male to maintain a breeding territory with temporary resources used by females and offspring during a critical period.
Abstract: Uniparental care often means that males do not contribute to the wellbeing of their offspring. For this reason, little attention has been given to avian species where the absent male contributes in...
TL;DR: Black Sparrowhawk Accipiter melanoleucus breeding behaviour and nest success was determined using camera traps and field observations in KwaZulu-Natal, South Africa and it was found that brooding duration decreased with chick age, while feeding frequency and duration increased.
Abstract: Black Sparrowhawk Accipiter melanoleucus breeding behaviour and nest success was determined using camera traps and field observations in KwaZulu-Natal, South Africa. Nest preparation was done predominantly by the male with incubation and brooding largely performed by the female. Brooding duration decreased with chick age, while feeding frequency and duration increased. Similarly, delivery of fresh leaf material to the nest site increased with chick age. Over the 2011 and 2012 breeding seasons respectively 74% and 41% of nests successfully fledged chicks, with the majority of these producing two offspring.
TL;DR: Although vulture ringing effort has improved in recent years very few new longevity records appear to be produced with most recent recoveries being under 10 years.
Abstract: Longevity and displacement records aid in the understanding of animal senescence and the possible range of a species. Within wild populations this information is infrequent with most longevity reports being based on captive individuals and displacements being calculated from few monitored individuals within the population. Ringing offers a means of calculating these values and for avian species SAFRING and other bird ringing schemes are critically important. As many vulture populations are under threat, it has become ever more important to analyse all aspects of their demography to understand what can be done to aid the conservation of these species. Southern Africa’s eight vulture species are almost all listed as globally threatened and as a result many studies incorporate this ringing information. This has allowed for longevity records to be calculated for most of the species with the Cape Vulture obtaining the greatest reported longevity of 31 years 2 months and 14 days. In addition to the longevity re...
TL;DR: In this article, the authors tracked a migrating adult Peregrine Falcon Falco peregrinus calidus from the border of Saudi Arabia and Yemen to near Cape Town, South Africa, a distance of 6 346 km.
Abstract: In boreal autumn 1995, we tracked a migrating adult Peregrine Falcon Falco peregrinus calidus from the border of Saudi Arabia and Yemen to near Cape Town, South Africa, a distance of 6 346 km. While on migration it covered 288 km d−1, on average. During its migration in Africa it migrated faster than any other Peregrine tracked so far using satellite telemetry. Falco p. calidus is an uncommon, but regular, migrant to southern Africa, where it overlaps with the resident F. p. minor, but no other bird has been tracked so far south.
TL;DR: In this paper, the authors investigated the nest success of the Indian house crow Corvus splendens in different tree species with varying canopy covers and heights, including mango Mangifera indica and madras thorn Pithecellobium dulce.
Abstract: Nest success of the Indian House Crow Corvus splendens was studied in the urban area of Dar es Salaam, Tanzania, in late March to early May 2011. The study investigated nest success of the Indian House Crow in different tree species with varying canopy covers and heights. Fifty-five active nests and 38 inactive nests were observed and inspected from six species of trees. Details of tree species, heights and canopy covers are provided. Apparent repeat clutches were found but there was no evidence of double brooding. Chi-square analysis of the distribution of the observed nests on trees with different characteristics revealed that nest success of the Indian House Crow was not significant with the selected nesting trees of particular species and height. Bonferroni simultaneous confidence intervals revealed that two exotic tree species, mango Mangifera indica and madras thorn Pithecellobium dulce, were the preferred tree species for nesting. The findings of this study showed that despite the selective behavio...
TL;DR: In this article, the authors used artificial nests to provide alternative nest sites for tree-cavity nesting birds, such as Cape Parrots and Poicep's parakeets.
Abstract: Breeding propensity of tree-cavity nesting bird species are often limited by a shortage of natural nesting sites. Artificial nests can be used to provide alternative nest sites. Cape Parrots Poicep...
TL;DR: Contrary to expectations, provisioning rates did not increase with age of the chick despite both adults delivering food, and growth of chicks showed a curvilinear relationship with age for the first 100 d with the tarsus and bill reaching maximum length after 80 d.
Abstract: Persistent vulture declines across Africa are a cause for concern as the number of species threatened with extinction increases The White-backed Vulture Gyps africanus was, until recently, considered abundant but has been declining rapidly in recent years due to various threats including decreasing food availability We used camera traps to investigate nest attendance and food provision at the nests of White-backed Vultures in north-eastern Swaziland Chick age influenced brooding behaviour of the parents, with a reduction in brooding time as the chick aged Mean food provision rate by parents to the nestling was 07 bouts d−1, which was mostly delivered between 09:00 and 15:00 Contrary to expectations, provisioning rates did not increase with age of the chick despite both adults delivering food The growth of chicks showed a curvilinear relationship with age for the first 100 d with the tarsus and bill reaching maximum length after 80 d We recommend further research into the availability of food for b
TL;DR: The authors explored movement patterns and survival using a long-term data set of 649 individually-marked birds and found that adults return to their natal site: 57% of adults were resig...
Abstract: The Western Cape population of Blue Cranes Anthropoides paradiseus is the species’ largest and most stable population. How this population utilises the agricultural landscape of the Western Cape, how far individuals disperse and the connectivity between subpopulations is unknown. Basic demographic parameters such as survival are also understudied. We explored movement patterns and survival using a long-term data set of 649 individually-marked birds. Resightings suggest that movements in the Western Cape were localised, with an average displacement of 24.6 km from their natal point. Displacement varied with age but not season. Despite regional differences in resighting effort, only 3.8% of individuals were observed in both the Overberg and the Swartland, suggesting high regional fidelity. However, there was significant movement within the Overberg, so Blue Cranes appear to be resident to locally nomadic in the Western Cape. There was evidence that adults return to their natal site: 57% of adults were resig...
TL;DR: The diet and time-activity budget of White-backed Mousebirds Colius colius at a coastal site in Western Cape province, South Africa was investigated and birds oriented their ventral parts towards the sun 93% of the time, suggesting that exogenous heating may be important for digestion.
Abstract: Mousebirds (Coliiformes) are unusual in having an exclusively vegetarian diet that includes substantial foliage and by using huddling and sunning to assist thermoregulation. Although previous studies have identified plant species and plant parts consumed by mousebirds, the relative importance of different food types in the diet of wild birds has not been investigated. Furthermore, there is limited information on the extent and importance of their sunning behaviour in the field. We investigated the diet and time-activity budget of White-backed Mousebirds Colius colius at a coastal site in Western Cape province, South Africa. Their diet consisted mostly of leaves (56% of items) and fruits (39%), but diet composition varied with time. Leaves had significantly higher protein content than fruits. White-backed Mousebirds spent most of their time (96%) in stationary activities, particularly sunning (60%), and allocated little time to feeding (4%). However, the proportion of time spent on different activities var...