Ostrich最新文献

{"title":"The role of experimental perches on the hover and perch hunting preferences of the Pied Kingfisher Ceryle rudis","authors":"G. Malan, Marco Heimstadt","doi":"10.2989/00306525.2023.2187893","DOIUrl":"https://doi.org/10.2989/00306525.2023.2187893","url":null,"abstract":"The Pied Kingfisher Ceryle rudis is a fishing kingfisher that employs two hunting modes. The bird can either hunt from a perch or hover and then dive into the water. The former method is energetically cheap but limits prey searching to the area below the perch, whereas hovering is costly but gives access to feeding areas that lack perches. This exploratory study examined how the provision of artificial perches influences the frequency of hover and perch hunting. In the hunting tracts with additional perches, 82% of 175 hunts were successful, but there was no correlation between the success of hunts and the presence of perches. However, hunting rates in tracts with extra perches were four-times higher than in control tracts. These results suggested that even though more perches did not improve the hunting success of Pied Kingfishers, the birds could increase their hunting rates, which probably enabled them to catch their daily fish requirements in a shorter time.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43695730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reproduction of the Western Marsh Harrier Circus aeruginosus at the El Maleh Dam reservoir in north-western Morocco","authors":"A. Rihane, A. Nahli, R. El Hamoumi, M. Chlaida","doi":"10.2989/00306525.2023.2206167","DOIUrl":"https://doi.org/10.2989/00306525.2023.2206167","url":null,"abstract":"The reproduction of the Western Marsh Harrier Circus aeruginosus in submerged and dried up thickets of French tamarisk Tamarix gallica at El Maleh Dam reservoir, Benslimane Province, Morocco, was studied through monitoring nests in three successive years (2017–2019). Systematic field investigation showed that the nests were concentrated exclusively in a narrow and shallow area upstream of the dam. The abundance of tamarisk is a determining factor in the breeding success of the Western Marsh Harrier at this site, by supporting the nests and giving them some protection from predation while the birds are close to agricultural fields, a favourable hunting ground. A study of individual broods revealed a relatively small clutch size (3.5 eggs per nest) and that incubation took 32 days on average. Compared with previous reports for this species elsewhere, the chicks fledged relatively early (33 or 35 days), but with a low fledgling success rate not exceeding 33.9%. The low fledgling success is partly attributable to the structure of the habitat, as the dense dry vegetation above the water level limits the movement of chicks out of nests yet favours the drowning of those that fall from the nest. Breeding success is influenced by a reduction in hunting territory caused by drops in the water level during periods of drought, poor climate conditions, and disturbance caused by human activities in the reservoir lake and riparian farmland. In addition to these environmental factors, nest failure due to nest destruction is related to the experience of the pairs in choosing the nesting site and their ability to weave the nest-building materials. Further study is needed on the characteristics of this highly specific habitat and its state of conservation, the reproduction of coexisting bird populations, and human activities around the breeding site.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48640149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nest-site selection by Levaillant’s Woodpecker Picus vaillantii in the Aurès Mountains of northeastern Algeria","authors":"Mehdi Badis, Imane Benchana, Nabil Hamdi","doi":"10.2989/00306525.2023.2185827","DOIUrl":"https://doi.org/10.2989/00306525.2023.2185827","url":null,"abstract":"We investigated ecological factors that influence the presence of nests of Levaillant’s Woodpecker Picus vaillantii in the Aurès Mountains of northeastern Algeria. Surveys carried out during the breeding season in 2018 and 2019, using point counts combined with extensive nest searching around each point at 72 random stations, allowed us to detect 44 nests against 28 unoccupied points. Using data on trees, deadwood, snags, canopy cover at the nest site, and elevation, we developed models reflecting landscape structure and forest composition. The results indicate that P. vaillantii prefers nesting in high-altitude forests and in dense canopies with high elevation. This reflects the importance of the forest composition, which is related to altitude, and the landscape structure, represented by the canopy cover, for the breeding of this species.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43903819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cape Parrot Poicephalus robustus diet in a nutshell: use of indigenous and exotic plants in the Eastern Cape province, South Africa","authors":"K. Wimberger, Kate F. Carstens, J. Carstens, Francis R Brooke, F. Rautenbach","doi":"10.2989/00306525.2022.2164805","DOIUrl":"https://doi.org/10.2989/00306525.2022.2164805","url":null,"abstract":"The success of conservation action for a threatened species can be improved by knowledge of its feeding and breeding requirements. The Cape Parrot Poicephalus robustus is a threatened endemic restricted to patches of mistbelt forest in South Africa. Cape Parrots are considered dietary specialists, preferring the kernels of yellowwood Podocarpus/Afrocarpus species, and consuming other species when these are not available. We investigated the diet composition of Cape Parrots in the Amathole region of the Eastern Cape province through targeted and opportunistic observations from 2016 to 2021. We monitored the availability of indigenous and exotic forest fruit over this timeframe and determined whether between-season and within-season differences were significant. We also monitored Cape Parrot presence and diet, weekly, at a pecan tree orchard and collected pecan nuts for compositional analysis. Additionally, we investigated whether Cape Parrots tracked this exotic feeding resource relative to local indigenous fruit abundance and changes in pecan nut composition. Cape Parrots were observed feeding on 36 tree species during this study, of which 61% were exotic. We recorded 24 new tree species (mostly exotics) not previously recorded as eaten by this parrot species. However, most feeding records were of parrots eating indigenous rather than exotic species, excluding the targeted observations of them eating at pecan orchards. Cape Parrots fed on pecans in each season despite the relatively high availability of indigenous forest fruits. Although not significant, Cape Parrots appeared to track changes in pecan nut composition during each season, gathering in the largest numbers when fat levels in the pecans were highest. Cape Parrots appear to be adapting to human-modified habitat based on the observations of annual visits to exotic pecan orchards and the high number of exotic species in their diet. The impact of exotic feeding resources on their health remains to be determined.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49118431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sunning in Yellow Bishops Euplectes capensis","authors":"H. Oschadleus, Philipp H. Boersch-Supan","doi":"10.2989/00306525.2023.2216375","DOIUrl":"https://doi.org/10.2989/00306525.2023.2216375","url":null,"abstract":"Two photographic records of a Yellow Bishop Euplectes capensis apparently sunning, at the West Coast National Park, South Africa, are described. There are very few records of sunning in weavers, and this is the first record for this species.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45624409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Conservation status and threats to lovebirds: knowledge gaps and research priorities","authors":"S. Dueker, S. Willows‐Munro, M. Perrin, Y. Abebe, Nathaniel ND Annorbah, E. Mwangi, I. Madindou, W. Tekalign, E. Mori, Tiwonge I Mzumara, C. Brown, Ursula Bryson, Henry K. Ndithia, T. Dodman, H. van der Zwan, R. van der Sluis, Chaona R Phiri, Abigail Karimanzira, Rowan O. Martin","doi":"10.2989/00306525.2023.2206674","DOIUrl":"https://doi.org/10.2989/00306525.2023.2206674","url":null,"abstract":"Lovebirds (genus Agapornis of family Psittaculidae) are a group of small, colourful parrot species endemic to sub-Saharan Africa and Madagascar, two-thirds of which are considered to have declining populations. Effective conservation efforts are hampered by a lack of information, particularly for species occurring in regions that have received little research attention. We combined expert knowledge with a review of the primary and grey literature to identify key knowledge gaps and priority conservation actions for this group of birds. Published studies were found to be largely concentrated on lovebird populations in southern Africa and, to a lesser extent in East Africa, and therefore mostly concern members of the ‘white eye-ring’ clade. Some species, such as the Black-collared Lovebird Agapornis swindernianus, remain very poorly studied, with a lack of even basic information such as georeferenced occurrence records. Several lovebird species were historically taken from the wild in large numbers for the international pet trade, leading to population declines. Although trade in wild lovebirds has been much reduced compared with historical levels, considerable numbers are still captured for local and international trade without any monitoring of the wild populations. Habitat change continues to drive declines in the population and range of some species, particularly those considered habitat specialists, such as the Nyasa Lovebird A. lilianae and the Black-cheeked Lovebird A. nigrigenis. However, changing habitat has also driven range expansions and, in combination with trade, has created numerous novel contact zones between formerly allopatric species, such as between Fischer’s Lovebird A. fischeri and Yellow-collared Lovebird A. personatus. Hybridisation has been widely reported, particularly in East Africa, and studies on the implications of this for conservation, building on recent advances in genetic tools, are urgently needed. We call for more targeted research on lovebirds to inform assessments of their population trends, to understand the drivers of these trends, and to highlight opportunities to leverage existing data and new research tools to advance knowledge to support conservation in this group of birds.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41276158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Initial evaluation of the care and rehabilitation success of Cape Cormorants Phalacrocorax capensis rescued from Robben and Jutten islands, South Africa, in January 2021","authors":"J. Phillips, K. Ludynia, L. Waller, Peter J Barham, Andile Mdluli, Romy Klusener, G. Maneveldt","doi":"10.2989/00306525.2023.2173327","DOIUrl":"https://doi.org/10.2989/00306525.2023.2173327","url":null,"abstract":"The population of the endangered Cape Cormorant Phalacrocorax capensis more than halved over the last three decades (BirdLife International 2018a). In January 2021, nearly 2 000 Cape Cormorant chicks were found abandoned, suffering from dehydration and heat stress, at two important nesting sites. The chicks were rescued and rehabilitated by the Southern African Foundation for the Conservation of Coastal Birds (SANCCOB, Cape Town, South Africa). About half (53.7%) of the cormorant chicks were successfully rehabilitated and released back into the breeding colonies. This study found a direct link between the initial body mass of cormorant chicks admitted to the rehabilitation centre and their probability of surviving during rehabilitation, with birds that were initially heavier having a greater probability of eventual release. Most cormorant chicks that died (80.7%) did so within the first 5 days of admission. This rescue required SANCCOB to care for and rehabilitate the largest number of Cape Cormorant chicks that has ever been admitted to its rehabilitation centre at one time, making it the first rescue of its kind. Despite the presumably limited positive impact on overall population numbers of Cape Cormorants, the rescue campaign improved SANCCOB’s preparedness to respond successfully to future disaster events and to deal with different species, both locally and globally.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48347458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Natural recolonisation of sub-Antarctic Marion Island by Common Diving Petrels Pelecanoides urinatrix","authors":"M. Connan, S. Schoombie, J. Schoombie, B. Dilley, P. Ryan","doi":"10.2989/00306525.2022.2150706","DOIUrl":"https://doi.org/10.2989/00306525.2022.2150706","url":null,"abstract":"Nocturnal burrow-nesting seabirds are notoriously difficult to study and can go unnoticed for years in remote areas. One of these species is the Common Diving Petrel Pelecanoides urinatrix, which has a circumpolar breeding distribution in the Southern Ocean, including at the sub-Antarctic Prince Edward Islands. At Marion Island, the larger of the two islands, the species was extirpated by cats that were introduced in 1948. The cats were eradicated by 1991, and Common Diving Petrels were discovered in burrows in coastal Poa cookii (Cook’s tussock grass) on a steep south-facing slope in Goodhope Bay during April 2015. Subsequent surveys in October 2015 and February 2016 confirmed breeding over a 1-ha area. In 2019/2020, breeding phenology and success was studied in 36 nests at the same site. Birds called from their burrows from mid-September, laying started in early October, and the first chick was observed on 20 December. Hatching peaked in early January and chicks fledged from the end of February to mid-March. This breeding phenology is similar to that at the neighbouring Crozet Archipelago. Overall nest survival was 46.4 ± 9.2% (mean ± SE; 95% CI: 29.5–64.1%), with most failures happening around hatching time. Further monitoring is needed to assess whether introduced House Mice Mus musculus contributed to the low hatching success. Common Diving Petrels were discovered breeding in other coastal areas, mostly in the south and east of the island. It is unlikely that breeding by this species was overlooked for three decades, suggesting that the elimination of cats allowed Common Diving Petrels to recolonise the island.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48627993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Breeding status of invasive Rose-ringed Parakeets Psittacula krameri in Durban, South Africa","authors":"Tinyiko C. Shivambu, Ndivhuwo Shivambu, C. Downs","doi":"10.2989/00306525.2022.2155719","DOIUrl":"https://doi.org/10.2989/00306525.2022.2155719","url":null,"abstract":"The Rose-ringed Parakeet Psittacula krameri has established feral populations in South African suburban areas. However, the information on the breeding biology of parakeets remains poorly documented in the country. We assessed parakeets’ breeding status and behaviour by locating their roost and breeding sites in Durban, eThekwini Metropole, KwaZulu-Natal province. We also placed artificial nest boxes to determine the occupancy of parakeets or other bird species. We identified 39 parakeet breeding sites with a total of 72 nests. There were no significant differences between the number of active parakeet nests in the first (n = 53 nests) and second breeding seasons (n = 59). Rose-ringed Parakeets used four tree species for nesting, with the white milkwood Sideroxylon inerme used the most (71%). Only East African lowland honey bees Apis mellifera scutellata and Common Mynas Acridotheres tristis used the artificial nest boxes. Parakeet fledgings recorded ranged between one and three per nest, and their numbers differed significantly between seasons. The number of fledglings was not influenced by any of the tree variables measured and distance or location. The distance between the parakeets’ roosting and breeding sites ranged from 1.43 to 5.0 km. Our study provides essential data for an overall management strategy, including eradication programs for this species in South Africa.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41448702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Road counts reveal The Gambia’s West Coast region still has the densest population of Hooded Vultures Necrosyrtes monachus in Africa","authors":"Mawdo Jallow, Momodou L Dibba, Fagimba Camara, D. Barber, K. Bildstein, Lindy J. Thompson","doi":"10.2989/00306525.2022.2143922","DOIUrl":"https://doi.org/10.2989/00306525.2022.2143922","url":null,"abstract":"Road surveys are a useful tool for comparing vulture population trends. Here we present data from road surveys to count Hooded Vultures Necrosyrtes monachus in The Gambia in 2017 and 2021. In the first nationwide road survey in November 2017 (during this species’ breeding period), we counted 7.3 Hooded Vultures per km. In The Gambia’s West Coast, we counted 33.3 Hooded Vultures per km in November 2017 (during this species’ breeding period) and 27.4 Hooded Vultures per km in May 2021 (during the non-breeding period). In the rest of the country (i.e. in The Gambia’s North Bank, Central, Upper and Lower River regions), we counted 3.3 Hooded Vultures per km in November 2017 and 2.1 Hooded Vultures per km in November 2021, which may represent cause for concern. These figures for The Gambia’s West Coast region far exceed the results of road surveys conducted in the same area in 2005, 2013, and 2015. The number of Hooded Vultures recorded per km in the West Coast region increased from 2005 to 2017, but dipped slightly into May 2021, when we would have expected to see an increase, as the 2021 survey was carried out in the non-breeding period. In the non-breeding period vultures would not be confined to nests and populations should be at their highest, due to recently fledged juveniles entering the population. Overall, the densities of Hooded Vultures counted in The Gambia from 2005 to 2021 indicate that population densities are higher in The Gambia than in any other country where road surveys have taken place. The densities were orders of magnitude higher than those in eastern and southern Africa. However, given the decline in numbers between 2017 and 2021, we should not be complacent about the stability of this population.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43410525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}