Ostrich最新文献

{"title":"The influence of nest location and the effect of predator removal on Cape Gannet Morus capensis egg predation by Kelp Gulls Larus dominicanus vetula","authors":"Zanri Strydom, L. Waller, Mark Brown, H. Fritz, J. Venter","doi":"10.2989/00306525.2022.2110535","DOIUrl":"https://doi.org/10.2989/00306525.2022.2110535","url":null,"abstract":"The breeding range of the Cape Gannet Morus capensis currently extends to six of the ten islands formerly utilised by this species. The Cape Gannet is classified as an endangered species with a rapidly declining population. Since the mid-1950s, the global population has declined by 51% due to multiple causes, including egg predation by the Kelp Gull Larus dominicanus vetula. To assess the effect of this predation, we monitored 100 nests over an 11-week period in 2018 at the Lambert’s Bay colony in South Africa. To assess the effect of selective predator removal on the likelihood of predation, data were collected from 2006 and 2018. Our objective was to assess whether nest location and predator removal affected the likelihood of egg predation. The peripheral nests saw a higher level of egg loss (average 1.5 eggs per week) compared with the central nests (average 1 egg per week). Predator control of Kelp Gulls was implemented in 2015, 2017 and 2018. Between years, selective culling decreased the number of Cape Gannet eggs predated. However, within years, except for 2015, the predation rate on Cape Gannet eggs increased post-culling during the same year of implementation. In all three of the implementation years, predation started again (within 48 hours) after the culling commenced. Predation by this indigenous gull species is natural; however, certain human activities might have supported larger populations of Kelp Gulls leading to elevated predation intensity. The most notable being the ever-increasing existence of dumpsites and other sources of food. Predation is affecting the Cape Gannet breeding population; therefore, we suggest that an alternative, long-term, and sustainable solution be planned and implemented to reduce the effects thereof.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44181340","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":"How do we feel, African Ornithology? A sentiment analysis search for symptoms of eco-anxiety","authors":"Alan T. K. Lee","doi":"10.2989/00306525.2022.2114640","DOIUrl":"https://doi.org/10.2989/00306525.2022.2114640","url":null,"abstract":"Ostrich is co-published by NISC (Pty) Ltd and Informa UK Limited (trading as Taylor & Francis Group) This year the Cape Gannet Morus capensis has been chosen as South Africa’s Bird of the Year. A beautiful coastal bird, I have seen these foraging in large flocks which give the impression they are common and doing well, and so it has been concerning to learn that the species is Endangered, with ongoing population declines on its island colonies. The population is under pressure for food resources, as well as from natural predators, as we learn in Strydom et al. (2022). Koopman (2022) quotes this text as a description from over 100 years ago: ‘The Malagash, as it is called by the Colonists, or Common Gannet of South Africa, frequents, in countless thousands, the whole of our coastline....’. It is certainly countable in 2022 and becoming more so with passing time with fewer and fewer to count. This is a depressing situation, and yet another unfolding ecological tragedy. Learning about Cape Gannet made me sad, but it is not the only thing. Unfortunately, it appears we live in ‘interesting times’ as per the alleged Chinese curse. The past two years have been torrid, and I suspect few have not been affected by inconvenience at least, or the loss of loved ones at worst, due to the global COVID-19 pandemic and associated lockdowns. As I write, the situation in Europe is very unsettled with the invasion of Ukraine by Russia. All this is set against the backdrop of climate change, with a mounting portfolio of associated disasters. Over the last decade we’ve also seen political polarisation, and a backlash against everything deemed to be too ‘left’, into which conservation initiatives are frequently lumped (Scholes 2013). In Africa, we are seeing the loss of natural environments to a combination of urban and agricultural expansion, ‘big development’, alien vegetation encroachment, human population pressure, climate change impacts resulting in floods, fires and droughts (Lees et al. 2022). We’ve seen the terms ‘eco-anxiety’ and ‘ecological grief’ coined to describe how people with a connection to nature now feel when faced with the loss of something very close to them, something with which there is a real emotional bond (Cunsolo and Ellis 2018). Grief is a powerful emotion: a rip in the fabric of our reality, but unlike grief felt with the passing of a loved one, ecological grief never ends: each tragedy is replaced by the next (Read 2022). The past two years has seen a lot of media attention on mental health. United Nations Secretary General Antonio Guterres warned that psychological suffering will outlast the coronavirus crisis, stating on 13 May 2020: ‘Even when the pandemic is brought under control, grief, anxiety and depression will continue to affect people and communities’. But how did we feel before and how do we feel now? Can we detect a changing pattern of sentiment in the titles and abstracts of some scientific journals? Although those should by t","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47435381","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":"Sexual and individual signatures are encoded in the temporal rate of Cape Gannet Morus capensis display calls","authors":"Kezia Bowmaker-Falconer, A. Thiebault, M. Connan, T. Aubin, I. Charrier, P. Pistorius","doi":"10.2989/00306525.2022.2113926","DOIUrl":"https://doi.org/10.2989/00306525.2022.2113926","url":null,"abstract":"Vocalisations play a vital role in animal communication, as they are involved in many biological functions such as mate selection, individual recognition and care of young. Seabirds often breed in large and dense colonies, making successful recognition between mates or between parents and offspring crucial for reproductive success. Acoustic signals have been shown to play an important role in this regard for several seabird species. Furthermore, most seabird species, including the Cape Gannet Morus capensis, are monomorphic, making sex identification for research challenging. Identifying individual and sexual signatures in their vocal productions could thus facilitate sex identification in the field. This study aimed to better understand the potential use of vocalisations for sex and individual recognition in Cape Gannets by describing the acoustic structure of their display calls at the nest. Vocalisations of nesting Cape Gannets were recorded over a two-week period. Acoustic measurements were extracted from 80 calls (16 individuals) and included 36 variables in both temporal and frequency domains. Twenty acoustic variables showed significant differences in vocalisations between male and female Cape Gannets. However, values of the fundamental frequency and the average of Inter-Onset-Interval (time elapsed between successive sound units) appeared to be the most important acoustic variables for sex determination. Both temporal and frequency parameters showed a potential for individual identity coding, again with the average units’ Inter-Onset- Interval being the most important variable for individual identification for both females and males. This study provides the first evidence of sex-specific and individual vocal signatures in adult breeding Cape Gannets enhancing our understanding of the role of the display calls in mate recognition. From an applied perspective, identified sex-specific differences could potentially be used as a non-invasive method for field-based sex-determination.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41635515","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":"Genetic and morphological variation of Woodland Kingfisher Halcyon senegalensis reveals cryptic mitochondrial lineages and patterns of mitochondrial–nuclear discordance","authors":"M. Mwale, D. Dalton, A. S. Kropff, Kim Labuschagne, Isa-Rita M. Russo, S. T. Osinubi","doi":"10.2989/00306525.2022.2066215","DOIUrl":"https://doi.org/10.2989/00306525.2022.2066215","url":null,"abstract":"The Woodland Kingfisher Halcyon senegalensis is widely distributed throughout sub-Saharan Africa and occupies a wide variety of woodland and savannah habitat. Thus far, three subspecies have been described based on morphological variation. In the present study, using western, eastern and southern African populations, we examined the relationship between morphological and genetic divergence among two named subspecies, H. s. cyanoleuca and H. s. senegalensis, using three mitochondrial markers (CO1, Cytb, 16S) and two nuclear markers (FIB5 and RAG1). Southern birds showed clear evidence for morphological divergence, with a longer wing and tail length, when compared with eastern and western birds. Phylogenetic analyses using Bayesian methods identified two well-characterised genetic clusters, representing the two subspecies. We determined that H. s. senegalensis and H. s. cyanoleuca are closely related subspecies that split recently, approximately 0.66–1.31 MYA in the Pleistocene. Furthermore, genetic substructure was evident within H. s. senegalensis, with three distinct genetic clusters in each region. The separation between the Ghana+Gabon and Uganda lineages of H. s. senegalensis occurred approximately 0.12–0.57 MYA. Nuclear–mitochondrial discordance was detected, however, wherein the pattern of divergence was not detected in the RAG1 and FIB5 sequences. Our results suggest that climate change, biogeographic barriers and local adaptation has played a role in the diversification of Woodland Kingfishers in Africa.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45159745","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":"Gill Memorial Medal citation: Peter Ryan","authors":"C. Spottiswoode","doi":"10.2989/00306525.2022.2090769","DOIUrl":"https://doi.org/10.2989/00306525.2022.2090769","url":null,"abstract":"","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41453067","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":"Population trends of resident and migrant West African bird species monitored over an 18-year period in central Nigeria","authors":"Joy Akpanta Ishong, Joseph K. Afrifa, Soladoye B. Iwajomo, Justus P. Deikumah, S. Ivande, W. Cresswell","doi":"10.2989/00306525.2022.2068691","DOIUrl":"https://doi.org/10.2989/00306525.2022.2068691","url":null,"abstract":"Almost no systematic monitoring of bird population trends occurs in West Africa, despite rapid human population increase, habitat change, and climate change, making conservation planning problematic. We monitored bird population trends using constant-effort mist netting, in a newly protected area (Amurum Forest Reserve) on the outskirts of Jos, central Nigeria, from 2002 to 2019. We modelled the 18-year changes in trends of 10 Palearctic migrant and 41 common resident bird species and related this to any changes in annual environmental site quality using NDVI and rainfall data. The populations of most bird species were stable; 30% of migrants and 7% of residents increased, while 10% of migrants and 29% of residents declined moderately. Primary productivity, measured by NDVI, increased, and rainfall pattern was stable, suggesting that environmental conditions at the site improved slightly during the period. However, only a few species showed significant correlations of population trends with NDVI and rainfall. Overall, our results suggest that population changes were locally similar for both the Afro-Palearctic and resident bird species, being reasonably stable or increasing — although perhaps this reflected the fact that the monitoring was done within a newly protected area, which at present represents the best habitat in the wider locality. Those species that declined were mostly associated with open, grassland areas, which will have decreased as anthropogenic influences were reduced at the study site. Though we only monitored one site, the results are encouraging in that simple protection of a small habitat fragment (∼300 ha) in Nigeria yielded generally positive population benefits for both resident and Palearctic migrant species.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43404878","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":"The names and naming of gannets comprising the genus Morus (family Sulidae)","authors":"A. Koopman","doi":"10.2989/00306525.2022.2082576","DOIUrl":"https://doi.org/10.2989/00306525.2022.2082576","url":null,"abstract":"The gannet species found in the northern hemisphere can be fully identified as the Northern Gannet Morus bassanus in the family Sulidae. This full identity reveals four historical themes which intertwine to produce a number of historical and current names for both the Northern Gannet and the Cape Gannet Morus capensis. These four themes are (1) the ‘goose’ theme, which traces the word ‘goose’ back to its Sanskrit origin hainsas, and which over centuries has spawned linguistically related words like gander, gannet and the erstwhile Latin family name Anseridae; (2) the ‘sula’ theme, which traces the echoes of the Old Norse word súla ‘gannet’, giving a number of names for the Northern Gannet in various European languages, as well as the family name Sulidae; (3) the Bass Rock in the Firth of Forth in Scotland, associated with the Northern Gannet for centuries and responsible for the specific epithet bassanus; and (4) notions of various seabirds being foolish or silly, leading to the generic name Morus, and various names for seabirds such as the current Afrikaans malgas (Cape Gannet) and the historical mallemuck, and variants for various species of albatross. In this diachronic review of these four themes, a special look is taken of names for the Cape Gannet as recorded in the ships’ logs of early mariners rounding and landing at the Cape in the seventeenth and eighteenth centuries. Here Portuguese names like Mangas de Veludo (‘velvet sleeves’) are also recorded. The article concludes by looking at echoes of these four themes in the names of the Australasian Gannet Morus serrator.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44657249","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":"Wing-moult and seasonal occurrence of sunbirds (Nectariniidae) captured at four sites in the Eastern Cape, South Africa","authors":"B. Bonnevie, A. Craig, P. Hulley, A. Schultz, A. J. Tree","doi":"10.2989/00306525.2022.2075482","DOIUrl":"https://doi.org/10.2989/00306525.2022.2075482","url":null,"abstract":"","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41843571","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":"Host specificity of the Pygmy Falcon Polihierax semitorquatus: a review","authors":"H. Oschadleus","doi":"10.2989/00306525.2022.2079011","DOIUrl":"https://doi.org/10.2989/00306525.2022.2079011","url":null,"abstract":"The Pygmy Falcon Polihierax semitorquatus does not build its own nest but is an obligate user of the nests of colonial birds for roosting and breeding. The nests of various weavers and starlings have been listed, suggesting a wide range of hosts used by the Pygmy Falcon. A search for original references of host use, however, suggests a high degree of host specificity. The two disjunct populations of Pygmy Falcon each specialise on a single weaver host, namely the Sociable Weaver Philetairus socius in the southern population, and the White-headed Buffalo Weaver Dinemellia dinemelli in the eastern population. There are incidental records of roosting or breeding in the nests of the White-browed Sparrow-Weaver Plocepasser mahali and Red-billed Buffalo Weaver Bubalornis niger. No records of Pygmy Falcons using starling nests have been confirmed.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49413970","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":"An ethogram for the nesting and breeding behaviour of the Hooded Vulture Necrosyrtes monachus","authors":"Fiona K Fern, Lindy J. Thompson, C. Downs","doi":"10.2989/00306525.2022.2072965","DOIUrl":"https://doi.org/10.2989/00306525.2022.2072965","url":null,"abstract":"Most vulture species worldwide are in decline and of conservation concern. Despite the growing attention to vultures, relatively few studies have focused on their breeding behaviour. Understanding all aspects of a species’ behaviour and its behavioural needs could help to inform conservation efforts. Behavioural studies can be enhanced with the use of an ethogram that clearly defines and describes distinct behaviours. We present the first ethogram detailing the nesting and breeding behaviours of the Critically Endangered Hooded Vulture Necrosyrtes monachus, compiled from over 400 000 nest camera photographs and from hours of direct personal observations at nests in north-eastern South Africa. We describe 28 behaviours that Hooded Vultures exhibited in and around their nests, and these fell into five discrete categories: Movement, Resting, Body Care, Social, and Nesting. We also present 34 camera trap images depicting behaviours from within each category, and discuss the uses and limitations of behaviour-recording technologies. Many of these behavioural elements may be common across vulture species, and so this ethogram may be a useful starting point for other researchers studying vultures globally.","PeriodicalId":54655,"journal":{"name":"Ostrich","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49667293","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}