Pub Date : 2023-06-05DOI: 10.1080/01584197.2023.2214580
K. Reid, G. Baker, R. Wells
ABSTRACT Although there is an increasing awareness of the high rates of seabird bycatch in trawl fisheries globally, there is relatively limited implementation of effective mitigation measures. Seabirds that are attracted to the stern of the trawl vessel to feed on fish-waste can be drowned or injured when they collide with warps/cables or when they become entangled in nets. Managing fish-waste discharge (processing offal and discards) and limiting access to it by scaring birds have been identified as the most effective measures to reduce seabird mortality from collisions with warps. New Zealand’s arrow squid (Nototodarus spp.) trawl fishery occurs during the austral summer and autumn when there is significant overlap with large numbers of foraging seabirds due to the proximity of breeding areas. Regulations introduced by the New Zealand government in 2007 requiring the use of devices to reduce warp strikes and operational procedures to manage fish-waste were independently implemented by the fishing industry in 2007 with the support of fishery regulators. The rate of capture of albatrosses by warps decreased from a mean of 2.9 birds per 100 tows during the period 2003 to 2006 to a mean of 0.7 birds per 100 tows after 2007. Long-term ownership of squid fishery quota catalysed the proactive engagement of the industry and has been reflected in a positive cultural shift in the attitude of fishers towards managing the risk of the capture of seabirds. Multi-sector collaboration and engagement allowed for the translation of experimental mitigation results into long-term, industrial-scale operational practices.
{"title":"Mitigation of seabird bycatch in New Zealand squid trawl fisheries provides hope for ongoing solutions","authors":"K. Reid, G. Baker, R. Wells","doi":"10.1080/01584197.2023.2214580","DOIUrl":"https://doi.org/10.1080/01584197.2023.2214580","url":null,"abstract":"ABSTRACT Although there is an increasing awareness of the high rates of seabird bycatch in trawl fisheries globally, there is relatively limited implementation of effective mitigation measures. Seabirds that are attracted to the stern of the trawl vessel to feed on fish-waste can be drowned or injured when they collide with warps/cables or when they become entangled in nets. Managing fish-waste discharge (processing offal and discards) and limiting access to it by scaring birds have been identified as the most effective measures to reduce seabird mortality from collisions with warps. New Zealand’s arrow squid (Nototodarus spp.) trawl fishery occurs during the austral summer and autumn when there is significant overlap with large numbers of foraging seabirds due to the proximity of breeding areas. Regulations introduced by the New Zealand government in 2007 requiring the use of devices to reduce warp strikes and operational procedures to manage fish-waste were independently implemented by the fishing industry in 2007 with the support of fishery regulators. The rate of capture of albatrosses by warps decreased from a mean of 2.9 birds per 100 tows during the period 2003 to 2006 to a mean of 0.7 birds per 100 tows after 2007. Long-term ownership of squid fishery quota catalysed the proactive engagement of the industry and has been reflected in a positive cultural shift in the attitude of fishers towards managing the risk of the capture of seabirds. Multi-sector collaboration and engagement allowed for the translation of experimental mitigation results into long-term, industrial-scale operational practices.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"4 4 1","pages":"195 - 205"},"PeriodicalIF":1.3,"publicationDate":"2023-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81820410","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}
Pub Date : 2023-05-31DOI: 10.1080/01584197.2023.2214581
Aurore Counilh, J. Arnould
ABSTRACT Banding has historically been the most efficient method of marking individuals to gather large datasets on bird movement, especially in seabirds which spend a large proportion of their life-cycle at sea. The Australian Bird and Bat Banding Scheme has gathered such long-term records, including for the Australasian Gannet (Morus serrator). Between 1954 and 2022, a total of 12,583 bands were deployed at seven breeding sites in Australia, of which 522 were recovered dead. An additional 325 individuals from four banding sites in New Zealand were recovered along the Australian coastline. The effects of broadscale environmental indices on movement (inferred from banding recoveries) during the post-breeding period were investigated at two colonies with the most banding effort (Pope’s Eye, Lawrence Rocks). Individuals >1 year old and those from Pope’s Eye were recovered closer to their banding site. There were negative effects of current-year Southern Oscillation Index (SOI) and 1-year lagged Southern Annular Mode (SAM) on recovery distances for Lawrence Rocks individuals, while 2-year lagged SAM positively and negatively affected recovery distance and direction, respectively, for Pope’s Eye individuals. The number of chicks banded (index of chick production) at Pope’s Eye was negatively influenced by 1-year lagged SAM and 2-year lagged SOI, while the likelihood of recoveries of first-year individuals was positively influenced by 1-year lagged SAM. The results of the present study revealed a potential effect of environmental conditions on post-breeding movement with seemingly contrasting effects between colonies, and on reproduction, highlighting the usefulness of long-term banding and recovery efforts.
从历史上看，标记个体是收集鸟类运动大数据集的最有效方法，特别是对于那些在海洋中度过大部分生命周期的海鸟。澳大利亚鸟类和蝙蝠绑带计划收集了这样的长期记录，包括澳大利亚塘鹅(Morus serrator)。在1954年至2022年期间，在澳大利亚的七个繁殖地共部署了12583只带，其中522只被发现死亡。在澳大利亚海岸线上发现了另外325只来自新西兰四个栖息地的个体。在两个种群(Pope’s Eye, Lawrence Rocks)中，研究了大尺度环境指数对繁殖后种群运动的影响(从种群的条带恢复推断)。>1岁的个体和来自蒲柏之眼的个体在其结扎点附近被发现。南方涛动指数(SOI)和滞后1年的南方涛动模式(SAM)对Lawrence Rocks个体的恢复距离有负向影响，滞后2年的南方涛动模式对Pope’s Eye个体的恢复距离和恢复方向分别有正向和负向影响。1年滞后的SAM和2年滞后的SOI负向影响Pope’s Eye雏鸡的条带数(雏鸡产量指数)，而1年滞后的SAM正向影响第一年个体的恢复可能性。本研究的结果揭示了环境条件对繁殖后迁移和繁殖的潜在影响，这些影响在种群之间似乎是截然不同的，强调了长期带带和恢复努力的有用性。
{"title":"Environmental effects on movement and breeding of Australasian Gannets: insights from banding records","authors":"Aurore Counilh, J. Arnould","doi":"10.1080/01584197.2023.2214581","DOIUrl":"https://doi.org/10.1080/01584197.2023.2214581","url":null,"abstract":"ABSTRACT Banding has historically been the most efficient method of marking individuals to gather large datasets on bird movement, especially in seabirds which spend a large proportion of their life-cycle at sea. The Australian Bird and Bat Banding Scheme has gathered such long-term records, including for the Australasian Gannet (Morus serrator). Between 1954 and 2022, a total of 12,583 bands were deployed at seven breeding sites in Australia, of which 522 were recovered dead. An additional 325 individuals from four banding sites in New Zealand were recovered along the Australian coastline. The effects of broadscale environmental indices on movement (inferred from banding recoveries) during the post-breeding period were investigated at two colonies with the most banding effort (Pope’s Eye, Lawrence Rocks). Individuals >1 year old and those from Pope’s Eye were recovered closer to their banding site. There were negative effects of current-year Southern Oscillation Index (SOI) and 1-year lagged Southern Annular Mode (SAM) on recovery distances for Lawrence Rocks individuals, while 2-year lagged SAM positively and negatively affected recovery distance and direction, respectively, for Pope’s Eye individuals. The number of chicks banded (index of chick production) at Pope’s Eye was negatively influenced by 1-year lagged SAM and 2-year lagged SOI, while the likelihood of recoveries of first-year individuals was positively influenced by 1-year lagged SAM. The results of the present study revealed a potential effect of environmental conditions on post-breeding movement with seemingly contrasting effects between colonies, and on reproduction, highlighting the usefulness of long-term banding and recovery efforts.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"46 2 1","pages":"206 - 216"},"PeriodicalIF":1.3,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81875914","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}
Pub Date : 2023-05-31DOI: 10.1080/01584197.2023.2214573
L. Joseph, Heather G. Johnston, D. Thuo, Jéssica Fenker, A. Drew, I. Mason, C. Moritz, Anna M. Kearns
ABSTRACT Geographic overlap of Olive-backed Oriole O. sagittatus and the Green Oriole O. flavocinctus is extensive in northern Australia, but they generally are separated by habitat. They overlap in New Guinea, however, where their habitat distinction is much reduced. Genetic methods in an earlier study detected unexpected hybridisation between the two species in New Guinea. Here, we ask whether hybridisation between the two species may have gone unnoticed in northern Australia, whether genetic methods again may detect it, and whether this may relate to habitat management and conservation. We find no evidence for hybridisation in Australia and conclude that its occurrence in New Guinea is indeed likely related to the reduced habitat distinction between the two species there relative to their range in Australia. We also examine taxonomic corollaries of our genomic data.
在澳大利亚北部，橄榄背黄鹂(Olive-backed Oriole O. sagittatus)和绿黄鹂(Green Oriole O. flavocinctus)在地理上有广泛的重叠，但它们通常被栖息地分开。然而，它们在新几内亚重叠，在那里它们的栖息地区别大大减少。在早期的一项研究中，遗传方法在新几内亚发现了两个物种之间意想不到的杂交。在这里，我们问两个物种之间的杂交是否可能在澳大利亚北部被忽视，是否遗传方法可以再次检测到它，以及这是否可能与栖息地管理和保护有关。我们在澳大利亚没有发现杂交的证据，并得出结论，它在新几内亚的出现确实可能与两种物种之间的栖息地差异相对于它们在澳大利亚的范围缩小有关。我们也检查我们的基因组数据的分类学推论。
{"title":"Do Olive-backed Orioles and Green Orioles hybridize in Australia? A genomic assessment with taxonomic notes","authors":"L. Joseph, Heather G. Johnston, D. Thuo, Jéssica Fenker, A. Drew, I. Mason, C. Moritz, Anna M. Kearns","doi":"10.1080/01584197.2023.2214573","DOIUrl":"https://doi.org/10.1080/01584197.2023.2214573","url":null,"abstract":"ABSTRACT Geographic overlap of Olive-backed Oriole O. sagittatus and the Green Oriole O. flavocinctus is extensive in northern Australia, but they generally are separated by habitat. They overlap in New Guinea, however, where their habitat distinction is much reduced. Genetic methods in an earlier study detected unexpected hybridisation between the two species in New Guinea. Here, we ask whether hybridisation between the two species may have gone unnoticed in northern Australia, whether genetic methods again may detect it, and whether this may relate to habitat management and conservation. We find no evidence for hybridisation in Australia and conclude that its occurrence in New Guinea is indeed likely related to the reduced habitat distinction between the two species there relative to their range in Australia. We also examine taxonomic corollaries of our genomic data.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"30 1","pages":"244 - 249"},"PeriodicalIF":1.3,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84300888","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}
Pub Date : 2023-05-25DOI: 10.1080/01584197.2023.2193701
D. Potvin
{"title":"A guide to the creatures in your neighbourhood","authors":"D. Potvin","doi":"10.1080/01584197.2023.2193701","DOIUrl":"https://doi.org/10.1080/01584197.2023.2193701","url":null,"abstract":"","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"3 1","pages":"262 - 263"},"PeriodicalIF":1.3,"publicationDate":"2023-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76080242","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}
Pub Date : 2023-05-14DOI: 10.1080/01584197.2023.2205595
Annalea Beard, Renata Medeiros Mirra, Elizabeth Clingham, Leeann Henry, Robert J. Thomas, F. Hailer
ABSTRACT We describe the population size and breeding ecology of the Red-billed Tropicbird, Phaethon aethereus, a poorly studied pantropical seabird, at St Helena, South Atlantic. The population size of 81–246 pairs and 272–564 individuals identifies the study population as the largest colony of Red-billed Tropicbirds in the South Atlantic, but also an internationally important part of the global population. We estimated the survival from laying to fledging of 158 nests between 2004 and 2017 at only 33%, among the lowest values reported globally for the species. Most nest failures occurred during incubation, with predation identified as the predominant cause of fledging failure. Intervals between breeding attempts were longer after successful nesting attempts than failed attempts. Previous breeding interval and nest cavity fidelity further influenced the interval between breeding attempts, while the presence of replacement clutches did not. Multiple nest site and cavity characteristics were important predictors of cavity use, nest site selection and productivity. Management options for reducing mammalian predators to ensure the long-term viability of this important population at St Helena are discussed.
{"title":"Breeding ecology, population size and nest site preferences of Red-billed Tropicbirds at St Helena, South Atlantic Ocean","authors":"Annalea Beard, Renata Medeiros Mirra, Elizabeth Clingham, Leeann Henry, Robert J. Thomas, F. Hailer","doi":"10.1080/01584197.2023.2205595","DOIUrl":"https://doi.org/10.1080/01584197.2023.2205595","url":null,"abstract":"ABSTRACT We describe the population size and breeding ecology of the Red-billed Tropicbird, Phaethon aethereus, a poorly studied pantropical seabird, at St Helena, South Atlantic. The population size of 81–246 pairs and 272–564 individuals identifies the study population as the largest colony of Red-billed Tropicbirds in the South Atlantic, but also an internationally important part of the global population. We estimated the survival from laying to fledging of 158 nests between 2004 and 2017 at only 33%, among the lowest values reported globally for the species. Most nest failures occurred during incubation, with predation identified as the predominant cause of fledging failure. Intervals between breeding attempts were longer after successful nesting attempts than failed attempts. Previous breeding interval and nest cavity fidelity further influenced the interval between breeding attempts, while the presence of replacement clutches did not. Multiple nest site and cavity characteristics were important predictors of cavity use, nest site selection and productivity. Management options for reducing mammalian predators to ensure the long-term viability of this important population at St Helena are discussed.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"7 1","pages":"185 - 194"},"PeriodicalIF":1.3,"publicationDate":"2023-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79169127","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}
Pub Date : 2023-04-03DOI: 10.1080/01584197.2023.2194541
L. Bussolini, R. Crates, M. Magrath, D. Stojanović
ABSTRACT Captive breeding programs are an increasingly important tool for species’ conservation efforts, but not all species reproduce well in captivity. Identifying factors that affect the reproductive success of captive populations is crucial to improving the performance and management of conservation-breeding programs, both by providing individuals for release and informing decision making. We examined breeding records collected from the long-running conservation-breeding program for the critically endangered Orange-bellied Parrot Neophema chrysogaster over an 11-year period. We examined egg hatching rate, nestling survival rate, and offspring sex ratio in response to a wide range of variables related to characteristics of individual birds, breeding events, and the captive environment. The hatch rate of eggs was higher in first clutches compared to second clutches and was lower than the wild population. The survival rate of nestlings through to fledging was variable between years but became higher and more consistent over the last five years of the study period. Variation in brood sex ratio was not related to any of the potential explanatory variables that we examined. This is one of the first studies to examine reproductive data in a long-running conservation-breeding program and shows that many common metrics do not explain reproductive variation. Our approach provides a framework for managers to investigate factors affecting reproductive success in conservation breeding programs more broadly.
{"title":"Identifying factors affecting captive breeding success in a critically endangered species","authors":"L. Bussolini, R. Crates, M. Magrath, D. Stojanović","doi":"10.1080/01584197.2023.2194541","DOIUrl":"https://doi.org/10.1080/01584197.2023.2194541","url":null,"abstract":"ABSTRACT Captive breeding programs are an increasingly important tool for species’ conservation efforts, but not all species reproduce well in captivity. Identifying factors that affect the reproductive success of captive populations is crucial to improving the performance and management of conservation-breeding programs, both by providing individuals for release and informing decision making. We examined breeding records collected from the long-running conservation-breeding program for the critically endangered Orange-bellied Parrot Neophema chrysogaster over an 11-year period. We examined egg hatching rate, nestling survival rate, and offspring sex ratio in response to a wide range of variables related to characteristics of individual birds, breeding events, and the captive environment. The hatch rate of eggs was higher in first clutches compared to second clutches and was lower than the wild population. The survival rate of nestlings through to fledging was variable between years but became higher and more consistent over the last five years of the study period. Variation in brood sex ratio was not related to any of the potential explanatory variables that we examined. This is one of the first studies to examine reproductive data in a long-running conservation-breeding program and shows that many common metrics do not explain reproductive variation. Our approach provides a framework for managers to investigate factors affecting reproductive success in conservation breeding programs more broadly.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"58 1","pages":"161 - 169"},"PeriodicalIF":1.3,"publicationDate":"2023-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81604384","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}
Pub Date : 2023-04-03DOI: 10.1080/01584197.2023.2193900
Necmiye Şahin Arslan, D. Muñoz, T. E. Martin
ABSTRACT Whitehead’s Broadbill, Calyptomena whiteheadi, an endemic species on the island of Borneo, has a declining population, raising the question of whether reproduction might be a factor limiting population growth. We studied breeding biology based on 52 nests in Kinabalu Park, Sabah, Malaysian Borneo in 2009–2020. Length of the egg-laying season was 99 days with a median of 22 March. Clutch size was typical of tropical songbirds at 2.0 ± 0.13 eggs (SE). Nest success was relatively high at 52%, and daily nest predation rate was relatively low at 0.013 ± 0.004 (SE). Concordantly, length of incubation and nestling periods were relatively long at 19.0 ± 0.26 d and 26.8 ± 0.3 d (SE), respectively. Similarly, the growth rate constants (K) for mass, wing length and tarsus length were slow at 0.252, 0.161 and 0.188, respectively. Slow growth might result in part from their frugivorous diet, as we show using seed traps, but they are reported to include insects in their diets and food provided to their young. Feeding effort, as reflected by the number of fruit seeds dropped below the nest, increased through the nestling period. Brooding effort of parents for nestlings was high on hatch day and decreased until Day 10–15 when it stopped. Food and parental care efforts do not seem to cause their slow growth. Ultimately, our study population has reproductive success that suggests it is not limiting population growth, but studies are needed in other locations to determine if it is a problem elsewhere.
{"title":"Reproductive biology of the Whitehead’s Broadbill (Calyptomena whiteheadi)","authors":"Necmiye Şahin Arslan, D. Muñoz, T. E. Martin","doi":"10.1080/01584197.2023.2193900","DOIUrl":"https://doi.org/10.1080/01584197.2023.2193900","url":null,"abstract":"ABSTRACT Whitehead’s Broadbill, Calyptomena whiteheadi, an endemic species on the island of Borneo, has a declining population, raising the question of whether reproduction might be a factor limiting population growth. We studied breeding biology based on 52 nests in Kinabalu Park, Sabah, Malaysian Borneo in 2009–2020. Length of the egg-laying season was 99 days with a median of 22 March. Clutch size was typical of tropical songbirds at 2.0 ± 0.13 eggs (SE). Nest success was relatively high at 52%, and daily nest predation rate was relatively low at 0.013 ± 0.004 (SE). Concordantly, length of incubation and nestling periods were relatively long at 19.0 ± 0.26 d and 26.8 ± 0.3 d (SE), respectively. Similarly, the growth rate constants (K) for mass, wing length and tarsus length were slow at 0.252, 0.161 and 0.188, respectively. Slow growth might result in part from their frugivorous diet, as we show using seed traps, but they are reported to include insects in their diets and food provided to their young. Feeding effort, as reflected by the number of fruit seeds dropped below the nest, increased through the nestling period. Brooding effort of parents for nestlings was high on hatch day and decreased until Day 10–15 when it stopped. Food and parental care efforts do not seem to cause their slow growth. Ultimately, our study population has reproductive success that suggests it is not limiting population growth, but studies are needed in other locations to determine if it is a problem elsewhere.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"26 1","pages":"152 - 160"},"PeriodicalIF":1.3,"publicationDate":"2023-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85521705","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}
Pub Date : 2023-03-22DOI: 10.1080/01584197.2023.2186895
Aylen María de Prinzio, Sofía Copello, J. P. Seco Pon, Alejandro D. Canepuccia, R. Mariano-Jelicich
ABSTRACT Individual traits such as age-class can have profound effects on space utilisation by individual birds, with juvenile birds more often exhibiting dispersive movements. We studied the origin of juvenile Olrog’s Gulls Larus atlanticus, a threatened species, using stable isotopes ratios of carbon (δ13C), nitrogen (δ15N) and sulphur (δ34S). We analysed feathers from individuals captured in the wintering season at Mar Chiquita Coastal Lagoon, Argentina, and the potential trophic sources of their breeding sites at Bahía Blanca and San Blas. Mean δ13C was similar for trophic sources and mean δ15N was higher for Bahía Blanca. The δ34S showed a greater variation among prey species than among sites. The mean contributions of the main colonies resulted in assigning 37.5% individuals as from Bahía Blanca, 16.7% from San Blas, and 45.8% undetermined. Results indicate that Mar Chiquita coastal lagoon attracts juvenile Olrog’s Gulls dispersing from the two main breeding grounds of the species. This work is one of the first approaches to study the origin of dispersive juvenile larids through the application of stable isotope analysis. This isotopic approach allows obtaining trophic and movement information when it is not possible to use other tools.
{"title":"Where are you from? Isotopic tracing of juvenile Olrog’s Gulls from Mar Chiquita during the wintering season","authors":"Aylen María de Prinzio, Sofía Copello, J. P. Seco Pon, Alejandro D. Canepuccia, R. Mariano-Jelicich","doi":"10.1080/01584197.2023.2186895","DOIUrl":"https://doi.org/10.1080/01584197.2023.2186895","url":null,"abstract":"ABSTRACT Individual traits such as age-class can have profound effects on space utilisation by individual birds, with juvenile birds more often exhibiting dispersive movements. We studied the origin of juvenile Olrog’s Gulls Larus atlanticus, a threatened species, using stable isotopes ratios of carbon (δ13C), nitrogen (δ15N) and sulphur (δ34S). We analysed feathers from individuals captured in the wintering season at Mar Chiquita Coastal Lagoon, Argentina, and the potential trophic sources of their breeding sites at Bahía Blanca and San Blas. Mean δ13C was similar for trophic sources and mean δ15N was higher for Bahía Blanca. The δ34S showed a greater variation among prey species than among sites. The mean contributions of the main colonies resulted in assigning 37.5% individuals as from Bahía Blanca, 16.7% from San Blas, and 45.8% undetermined. Results indicate that Mar Chiquita coastal lagoon attracts juvenile Olrog’s Gulls dispersing from the two main breeding grounds of the species. This work is one of the first approaches to study the origin of dispersive juvenile larids through the application of stable isotope analysis. This isotopic approach allows obtaining trophic and movement information when it is not possible to use other tools.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"4 1","pages":"140 - 151"},"PeriodicalIF":1.3,"publicationDate":"2023-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84810930","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：