Pub Date : 2023-02-17DOI: 10.20417/nzjecol.47.3515
J. Leathwick, A. Byrom
: We review the recent rise to prominence in Aotearoa New Zealand of predation-focused conservation management, critically assessing the likelihood that this will deliver outcomes consistent with national biodiversity goals. Using a review of literature describing the impacts and control of three groups of introduced mammals (wild ungulates, brushtail possums, and predators), we identify shifts in management emphasis over a century of conservation decision-making in Aotearoa. Predators are now a major focus and wild ungulates are left largely uncontrolled, despite increasing populations and evidence for their negative impacts on a wide range of indigenous species and ecosystems. This imbalance in management effort, which appears to be influenced increasingly by socio-political pressures, is much less likely to deliver outcomes consistent with Aotearoa’s biodiversity goals than a systematic approach that addresses a full range of biodiversity threats. Overall, we interpret these shortcomings as reflecting long recognised issues with the governance and leadership of Aotearoa’s biodiversity system. Changes are required to provide adequate, stable funding, improve clarity around goals, leadership, responsibilities and accountabilities, strengthen planning and prioritisation of management actions, and coordinate management among various conservation actors. We also argue for (1) a stronger role for ecological sciences through independent research aimed at strengthening the evidence base for management actions, and (2) explicit inclusion of science expertise in conservation policy development and management decision making. While recent extensive, landscape-scale predator control has caught the imagination of many and has undoubtedly delivered some gains for a small subset of indigenous species, it also risks creating a false sense of achievement that diverts attention away from other serious gaps in progress towards achieving national biodiversity goals. We make 12 recommendations to address these shortcomings.
{"title":"The rise and rise of predator control: a panacea, or a distraction from conservation goals?","authors":"J. Leathwick, A. Byrom","doi":"10.20417/nzjecol.47.3515","DOIUrl":"https://doi.org/10.20417/nzjecol.47.3515","url":null,"abstract":": We review the recent rise to prominence in Aotearoa New Zealand of predation-focused conservation management, critically assessing the likelihood that this will deliver outcomes consistent with national biodiversity goals. Using a review of literature describing the impacts and control of three groups of introduced mammals (wild ungulates, brushtail possums, and predators), we identify shifts in management emphasis over a century of conservation decision-making in Aotearoa. Predators are now a major focus and wild ungulates are left largely uncontrolled, despite increasing populations and evidence for their negative impacts on a wide range of indigenous species and ecosystems. This imbalance in management effort, which appears to be influenced increasingly by socio-political pressures, is much less likely to deliver outcomes consistent with Aotearoa’s biodiversity goals than a systematic approach that addresses a full range of biodiversity threats. Overall, we interpret these shortcomings as reflecting long recognised issues with the governance and leadership of Aotearoa’s biodiversity system. Changes are required to provide adequate, stable funding, improve clarity around goals, leadership, responsibilities and accountabilities, strengthen planning and prioritisation of management actions, and coordinate management among various conservation actors. We also argue for (1) a stronger role for ecological sciences through independent research aimed at strengthening the evidence base for management actions, and (2) explicit inclusion of science expertise in conservation policy development and management decision making. While recent extensive, landscape-scale predator control has caught the imagination of many and has undoubtedly delivered some gains for a small subset of indigenous species, it also risks creating a false sense of achievement that diverts attention away from other serious gaps in progress towards achieving national biodiversity goals. We make 12 recommendations to address these shortcomings.","PeriodicalId":49755,"journal":{"name":"New Zealand Journal of Ecology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2023-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42047669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-10DOI: 10.20417/nzjecol.47.3514
Ann‐Kathrin V. Schlesselmann, J. Innes, Neil Fitzgerald, A. Monks, S. Walker
: Predation by mammals has been identified as the primary limiting factor of Aotearoa New Zealand native birds. Consequently, the ranges of many native forest bird species have contracted to cooler and higher elevation tracts of forest that support fewer introduced mammals. However, lower elevation forests are likely to be intrinsically more productive and able to sustain larger bird populations if control of mammalian pests removes predation as a primary limiting factor. We wanted to determine whether higher elevation forests provide less food for rat-sensitive, sedentary native insectivorous bird species, resulting in their reduced reproductive potential at higher elevations. In spring and summer 2020/21, we sampled invertebrate prey while simultaneously monitoring nest survival and number of fledglings produced by tītitipounamu / rifleman ( Acanthisitta chloris ) and miromiro / tomtit ( Petroica macrocephala ) across three elevational bands on Mount Pirongia, where mammal predators were suppressed. Tracking and camera indices together indicated that introduced mammals were at low relative abundance at all elevations, allowing us to investigate other habitat effects. Biomass of ground-dwelling invertebrates decreased with increasing elevation during the bird breeding season, but was similar across elevational bands later in the season. In contrast, biomass of flying or folivore invertebrates was independent of elevation and only showed clear seasonal trends. In both tītitipounamu and miromiro, nest survival rates marginally decreased with increasing available invertebrate prey, while the number of fledglings of successful nests marginally increased. There was no strong relationship between elevation and nest survival or number of fledglings. These results indicate no clear trend in the reproductive potential of tītitipounamu and miromiro with elevation but do suggest that food supply needs to be considered as an aspect of habitat quality that is related to reproductive success.
{"title":"Invertebrate food supply and reproductive success of two native forest passerines along an elevational gradient","authors":"Ann‐Kathrin V. Schlesselmann, J. Innes, Neil Fitzgerald, A. Monks, S. Walker","doi":"10.20417/nzjecol.47.3514","DOIUrl":"https://doi.org/10.20417/nzjecol.47.3514","url":null,"abstract":": Predation by mammals has been identified as the primary limiting factor of Aotearoa New Zealand native birds. Consequently, the ranges of many native forest bird species have contracted to cooler and higher elevation tracts of forest that support fewer introduced mammals. However, lower elevation forests are likely to be intrinsically more productive and able to sustain larger bird populations if control of mammalian pests removes predation as a primary limiting factor. We wanted to determine whether higher elevation forests provide less food for rat-sensitive, sedentary native insectivorous bird species, resulting in their reduced reproductive potential at higher elevations. In spring and summer 2020/21, we sampled invertebrate prey while simultaneously monitoring nest survival and number of fledglings produced by tītitipounamu / rifleman ( Acanthisitta chloris ) and miromiro / tomtit ( Petroica macrocephala ) across three elevational bands on Mount Pirongia, where mammal predators were suppressed. Tracking and camera indices together indicated that introduced mammals were at low relative abundance at all elevations, allowing us to investigate other habitat effects. Biomass of ground-dwelling invertebrates decreased with increasing elevation during the bird breeding season, but was similar across elevational bands later in the season. In contrast, biomass of flying or folivore invertebrates was independent of elevation and only showed clear seasonal trends. In both tītitipounamu and miromiro, nest survival rates marginally decreased with increasing available invertebrate prey, while the number of fledglings of successful nests marginally increased. There was no strong relationship between elevation and nest survival or number of fledglings. These results indicate no clear trend in the reproductive potential of tītitipounamu and miromiro with elevation but do suggest that food supply needs to be considered as an aspect of habitat quality that is related to reproductive success.","PeriodicalId":49755,"journal":{"name":"New Zealand Journal of Ecology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2023-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41623431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-26DOI: 10.20417/nzjecol.47.3513
N. Sandoval, Kay Denyer, Sasha Dowling, Dip Barot, Na Fan
: The National Wetland Trust constructed a 1400 m long pest exclusion fence around a 11 hectare site at Rotopiko and all mammals except mice have been eradicated from inside the fenced area. Since the completion of the pest proof fence, the number of roosting birds has increased dramatically. By removing mammalian pests, an unexpected sanctuary has been created for communal roosting birds such as starlings ( Sturnus vulgaris ) and sparrows ( Passer domesticus ). There is growing concern about the large amounts of bird faeces produced each day and the associated nutrient load particularly as the pest fence encircles a low nutrient peat lake. In this study two methods were developed for estimating the relative abundance of the large roosting congregation, based on (1) gridded plates for gathering guano and (2) the acoustic energy of the roost cacophony. The results showed that these methods were suitable for measuring the characteristics of the roosting community at multiple scales. For example, large variance in the abundance of roosting and diurnal birds, and minor changes in the roosting community according to seasonal fluctuations. The methods could support the management of the issue through being applied to assess and quantify the relative efficacy of preventive or control methods deployed to reduce the number of exotic birds. The findings of this study are site specific; however, the guano plates and sound recorders could be implemented to estimate large bird numbers at other sites facing a roosting bird problem.
{"title":"Testing the effectiveness of a novel approach to measure a large roosting congregation in a wetland ecosystem","authors":"N. Sandoval, Kay Denyer, Sasha Dowling, Dip Barot, Na Fan","doi":"10.20417/nzjecol.47.3513","DOIUrl":"https://doi.org/10.20417/nzjecol.47.3513","url":null,"abstract":": The National Wetland Trust constructed a 1400 m long pest exclusion fence around a 11 hectare site at Rotopiko and all mammals except mice have been eradicated from inside the fenced area. Since the completion of the pest proof fence, the number of roosting birds has increased dramatically. By removing mammalian pests, an unexpected sanctuary has been created for communal roosting birds such as starlings ( Sturnus vulgaris ) and sparrows ( Passer domesticus ). There is growing concern about the large amounts of bird faeces produced each day and the associated nutrient load particularly as the pest fence encircles a low nutrient peat lake. In this study two methods were developed for estimating the relative abundance of the large roosting congregation, based on (1) gridded plates for gathering guano and (2) the acoustic energy of the roost cacophony. The results showed that these methods were suitable for measuring the characteristics of the roosting community at multiple scales. For example, large variance in the abundance of roosting and diurnal birds, and minor changes in the roosting community according to seasonal fluctuations. The methods could support the management of the issue through being applied to assess and quantify the relative efficacy of preventive or control methods deployed to reduce the number of exotic birds. The findings of this study are site specific; however, the guano plates and sound recorders could be implemented to estimate large bird numbers at other sites facing a roosting bird problem.","PeriodicalId":49755,"journal":{"name":"New Zealand Journal of Ecology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2023-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49444919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-18DOI: 10.20417/nzjecol.47.3511
T. Greene, Tertia Thurley, B. Basse
: To test the long-term efficacy of mammalian pest control, annual distance sampling estimates of the density of North Island kākā ( Nestor meridionalis septentrionalis ) within the southern Waipapa Ecological Area (WEA), Pureora Forest Park from 2008–2020 are compared to previously published estimates made at the same sites and time of year (October) between 2000–2007. Kākā density increased approximately four-fold from an average of c. 0.5 (95% CI 0.5–0.6) birds ha −1 between 2000 and 2007 to c. 2.3 (95% CI 1.9–2.8) birds ha −1 in 2020. The average of rate of increase between 2000 and 2018 was c. 6.9% per annum. Kākā recovery is likely to be a function of multiple mast events and long-term (> 20 years), large-scale, frequent, effective control of possums ( Trichosurus vulpecula ) and probably mustelids. It is recommended that the current pest control as well as kākā and pest monitoring continue.
为了检验哺乳动物病虫害防治的长期效果，将2008-2020年在普雷奥拉森林公园南怀帕帕生态区内(WEA)的北岛kākā (Nestor meridionalis septentrionalis)密度的年度距离抽样估计值与2000-2007年在同一地点和同一时间(10月)发表的估计值进行了比较。Kākā密度从2000年至2007年的平均0.0.5 (95% CI 0.5 - 0.6)只/公顷增加到2020年的0.2.3 (95% CI 1.9-2.8)只/公顷，增加了约4倍。2000年至2018年的平均增长率为每年6.9%。Kākā恢复可能是多重事件和长期(大约20年)，大规模，频繁，有效控制负鼠(Trichosurus vulpecula)和可能的鼬鼠的功能。建议继续进行目前的虫害防治以及kākā和虫害监测。
{"title":"Recovery of North Island kākā (Nestor meridionalis septentrionalis) within Pureora Forest Park, 2000–2020","authors":"T. Greene, Tertia Thurley, B. Basse","doi":"10.20417/nzjecol.47.3511","DOIUrl":"https://doi.org/10.20417/nzjecol.47.3511","url":null,"abstract":": To test the long-term efficacy of mammalian pest control, annual distance sampling estimates of the density of North Island kākā ( Nestor meridionalis septentrionalis ) within the southern Waipapa Ecological Area (WEA), Pureora Forest Park from 2008–2020 are compared to previously published estimates made at the same sites and time of year (October) between 2000–2007. Kākā density increased approximately four-fold from an average of c. 0.5 (95% CI 0.5–0.6) birds ha −1 between 2000 and 2007 to c. 2.3 (95% CI 1.9–2.8) birds ha −1 in 2020. The average of rate of increase between 2000 and 2018 was c. 6.9% per annum. Kākā recovery is likely to be a function of multiple mast events and long-term (> 20 years), large-scale, frequent, effective control of possums ( Trichosurus vulpecula ) and probably mustelids. It is recommended that the current pest control as well as kākā and pest monitoring continue.","PeriodicalId":49755,"journal":{"name":"New Zealand Journal of Ecology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45570779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-06DOI: 10.20417/nzjecol.47.3510
T. Etherington, Philip O'Lyver, Leilani A. Walker
{"title":"Initiating open access licensing in the New Zealand Journal of Ecology to further promote ecological science and better align copyright with the intent of Te Tiriti o Waitangi","authors":"T. Etherington, Philip O'Lyver, Leilani A. Walker","doi":"10.20417/nzjecol.47.3510","DOIUrl":"https://doi.org/10.20417/nzjecol.47.3510","url":null,"abstract":"","PeriodicalId":49755,"journal":{"name":"New Zealand Journal of Ecology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67539644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-01DOI: 10.20417/nzjecol.47.3512
J. Ogden, G. Perry
: The arrangement of plant species along elevational gradients is prominent in the debate between individualistic versus community-unit concepts in plant ecology. We obtained elevational ranges (upper and lower elevation limits) for woody species and ferns on the three highest mountains on Aotea (Great Barrier Island), Aotearoa-New Zealand. These data allowed potential species composition to be obtained for any elevation and were analysed using regression, ordination, and classification. Both woody plants and ferns demonstrated linear declines in richness with increasing elevation. The three mountains were distinct in ordination space, and their differences increased with elevation and were most marked in the fern flora. Site classifications indicated a change in composition at c. 300 m for woody plants on Hirakimata. The elevational distribution patterns of individual species differed considerably between mountains. In particular, the higher-elevation flora of the highest peak (Hirakimata) was largely absent from the other two summits, despite these being within the elevational ranges of most of the missing species. This pattern supports Steenis’s (1972) hypothesis that species will be absent from, or ephemeral on, mountains not sufficiently high to intersect their zone of permanent establishment. A second observed pattern was that widespread forest species at lower elevations often did not extend to their potential upper limits on Hirakimata. These two patterns are clear for both woody plant species and ferns. Combining Steenis’s hypothesis with inferred redistribution of elevational vegetation during the Last Glacial and Holocene periods can explain these distributional patterns
{"title":"Ranges of woody plant species and ferns on forested elevational gradients on Aotea-Great Barrier Island, New Zealand: the role of zones of permanent and temporary establishment","authors":"J. Ogden, G. Perry","doi":"10.20417/nzjecol.47.3512","DOIUrl":"https://doi.org/10.20417/nzjecol.47.3512","url":null,"abstract":": The arrangement of plant species along elevational gradients is prominent in the debate between individualistic versus community-unit concepts in plant ecology. We obtained elevational ranges (upper and lower elevation limits) for woody species and ferns on the three highest mountains on Aotea (Great Barrier Island), Aotearoa-New Zealand. These data allowed potential species composition to be obtained for any elevation and were analysed using regression, ordination, and classification. Both woody plants and ferns demonstrated linear declines in richness with increasing elevation. The three mountains were distinct in ordination space, and their differences increased with elevation and were most marked in the fern flora. Site classifications indicated a change in composition at c. 300 m for woody plants on Hirakimata. The elevational distribution patterns of individual species differed considerably between mountains. In particular, the higher-elevation flora of the highest peak (Hirakimata) was largely absent from the other two summits, despite these being within the elevational ranges of most of the missing species. This pattern supports Steenis’s (1972) hypothesis that species will be absent from, or ephemeral on, mountains not sufficiently high to intersect their zone of permanent establishment. A second observed pattern was that widespread forest species at lower elevations often did not extend to their potential upper limits on Hirakimata. These two patterns are clear for both woody plant species and ferns. Combining Steenis’s hypothesis with inferred redistribution of elevational vegetation during the Last Glacial and Holocene periods can explain these distributional patterns","PeriodicalId":49755,"journal":{"name":"New Zealand Journal of Ecology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48701929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-28DOI: 10.20417/nzjecol.47.3492
K. McInnes, Micah Jenson, Inga Bolt, Pauline Howard, Sam Lee, Norma. MacDonald, Finlay Cox
Judas pigs (Sus scrofa) will be integral to the success of the proposed Auckland Island (45 891 ha) pig eradication. Judas pigs must be permanently unable to breed and reliably retain a radio-transmitter to enable tracking and retrieval. This study tested the techniques and practical requirements to undertake the procedures required to produce a Judas pig in a remote location. Four adult female wild pigs were captured using a netgun from a helicopter and processed at a base site in the field. They were anaesthetised using intramuscular injection of one of two anaesthetic protocols (ZoletilTM, ketamine and xylazine; or medetomidine, ketamine and butorphanol). Surgical sterilisation consisted of tubal ligation and resection via a ventral midline incision. Pigs received either a subcutaneous or intra-abdominal implanted radio-transmitter and had a radio-collar and radioear tag attached. The anaesthetic was reversed prior to release close to the capture location. Radio-tracking at 10 and 104 days showed all pigs had survived and radio-tracking was effective using all the transmitter types. Pigs were humanely dispatched and necropsied on day 104. No adverse events were detected from the surgeries or radio-transmitters. All transmitter types except one subcutaneous transmitter model were shown to be secure and had an effective radio range for a Judas pig programme. Pig growth rates implicate a limited humane collaring period and ear transmitters may be at greater risk of transmitter loss. Implantable intra-abdominal radio transmitters provide the most security, but multiple transmitters are advised. Surgical sterilisation by tubal ligation and resection under general anaesthesia using an intramuscular injection containing medetomidine, butorphanol and ketamine and reversed with atipamezole was shown to be feasible in field conditions.
{"title":"A field test of the anaesthetics, surgical methods and radio-transmitters required for producing Judas pigs for an eradication programme","authors":"K. McInnes, Micah Jenson, Inga Bolt, Pauline Howard, Sam Lee, Norma. MacDonald, Finlay Cox","doi":"10.20417/nzjecol.47.3492","DOIUrl":"https://doi.org/10.20417/nzjecol.47.3492","url":null,"abstract":"Judas pigs (Sus scrofa) will be integral to the success of the proposed Auckland Island (45 891 ha) pig eradication. Judas pigs must be permanently unable to breed and reliably retain a radio-transmitter to enable tracking and retrieval. This study tested the techniques and practical requirements to undertake the procedures required to produce a Judas pig in a remote location. Four adult female wild pigs were captured using a netgun from a helicopter and processed at a base site in the field. They were anaesthetised using intramuscular injection of one of two anaesthetic protocols (ZoletilTM, ketamine and xylazine; or medetomidine, ketamine and butorphanol). Surgical sterilisation consisted of tubal ligation and resection via a ventral midline incision. Pigs received either a subcutaneous or intra-abdominal implanted radio-transmitter and had a radio-collar and radioear tag attached. The anaesthetic was reversed prior to release close to the capture location. Radio-tracking at 10 and 104 days showed all pigs had survived and radio-tracking was effective using all the transmitter types. Pigs were humanely dispatched and necropsied on day 104. No adverse events were detected from the surgeries or radio-transmitters. All transmitter types except one subcutaneous transmitter model were shown to be secure and had an effective radio range for a Judas pig programme. Pig growth rates implicate a limited humane collaring period and ear transmitters may be at greater risk of transmitter loss. Implantable intra-abdominal radio transmitters provide the most security, but multiple transmitters are advised. Surgical sterilisation by tubal ligation and resection under general anaesthesia using an intramuscular injection containing medetomidine, butorphanol and ketamine and reversed with atipamezole was shown to be feasible in field conditions.","PeriodicalId":49755,"journal":{"name":"New Zealand Journal of Ecology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45110241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-28DOI: 10.20417/nzjecol.47.3500
S. Horn, R. Sagar, V. Frank, Finlay Cox, Paul Jacques, James Ware, Rose Hanley-Nikolls, Estelle Leask, Norm Macdonald, Micaela Kirby-Crowe, Mark Le Lievre, K. Broome
Pub Date : 2022-11-28DOI: 10.20417/nzjecol.47.3493
M. Rodríguez-Recio, R. Sagar, Lindsay Chan, Finlay Cox, Paul Jacques
: Restoration initiatives of ecosystems transformed by human actions require optimisation of eradication measures of introduced species, particularly in fragile insular ecosystems. We studied aspects of the spatial ecology of introduced feral cats ( Felis catus ) on subantarctic Auckland Island of New Zealand to assist eradication efforts of pests from this remote, biologically rich island. Firstly, we estimated home range sizes and identified core areas of activity based on movement-rooted dynamic Brownian bridge models. Second, we used resource selection functions with generalised linear mixed models to identify seasonal patterns of space use associated to topographic, vegetation and other landscape predictors. Lastly, we quantified cats daily movement rates within home ranges. Average home range size was larger than on other offshore islands and mainland New Zealand, which might relate to lower cat densities and the abundance and predictability of food resources on the island. Cats mostly selected mosaic areas of forest, shrubs and tall tussocks near the coast, and in predominantly flat areas or nearby steep cliffs, which are all typical habitats of seabirds and terrestrial birds. Cats also selected alpine short tussocks during the cold season, likely related to the upsurge of mice ( Mus musculus ) due to tussock mast seeding and to transiting to steep cliffy areas. Male cats had home ranges that were larger, contained more core areas, and covered longer daily distances in the warm season than females, which might be associated with different breeding and reproductive behaviour. Eradication tools will need to target all habitats on Auckland Island with increased efforts in areas of identified higher use by cats. Understanding aspects of pest species’ spatial ecology on offshore islands worldwide can assist decision-makers in optimising eradication programs such as Predator Free 2050 in New Zealand.
{"title":"Spatial ecology meets eradication of feral cats on Auckland Island","authors":"M. Rodríguez-Recio, R. Sagar, Lindsay Chan, Finlay Cox, Paul Jacques","doi":"10.20417/nzjecol.47.3493","DOIUrl":"https://doi.org/10.20417/nzjecol.47.3493","url":null,"abstract":": Restoration initiatives of ecosystems transformed by human actions require optimisation of eradication measures of introduced species, particularly in fragile insular ecosystems. We studied aspects of the spatial ecology of introduced feral cats ( Felis catus ) on subantarctic Auckland Island of New Zealand to assist eradication efforts of pests from this remote, biologically rich island. Firstly, we estimated home range sizes and identified core areas of activity based on movement-rooted dynamic Brownian bridge models. Second, we used resource selection functions with generalised linear mixed models to identify seasonal patterns of space use associated to topographic, vegetation and other landscape predictors. Lastly, we quantified cats daily movement rates within home ranges. Average home range size was larger than on other offshore islands and mainland New Zealand, which might relate to lower cat densities and the abundance and predictability of food resources on the island. Cats mostly selected mosaic areas of forest, shrubs and tall tussocks near the coast, and in predominantly flat areas or nearby steep cliffs, which are all typical habitats of seabirds and terrestrial birds. Cats also selected alpine short tussocks during the cold season, likely related to the upsurge of mice ( Mus musculus ) due to tussock mast seeding and to transiting to steep cliffy areas. Male cats had home ranges that were larger, contained more core areas, and covered longer daily distances in the warm season than females, which might be associated with different breeding and reproductive behaviour. Eradication tools will need to target all habitats on Auckland Island with increased efforts in areas of identified higher use by cats. Understanding aspects of pest species’ spatial ecology on offshore islands worldwide can assist decision-makers in optimising eradication programs such as Predator Free 2050 in New Zealand.","PeriodicalId":49755,"journal":{"name":"New Zealand Journal of Ecology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49345526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-28DOI: 10.20417/nzjecol.47.3485
Derek Brown, Finlay Cox
: Cattle ( Bos taurus ) were liberated on 695 ha Enderby Island, the northernmost of the Auckland Island group, in 1894–96, after a previous liberation had died out. After reaching a peak population of c. 100 animals, they established a relatively stable population of 35–60 animals for the latter half of the 20th century. Eradication was mandated in the 1987 Auckland Islands Management Plan, but proposals for eradication were not universally supported due to the interesting traits of this long-isolated population and its adaptation to the subantarctic environment of the island. Therefore, retrieval of genetic material was permitted before the planned operation. Eradication of the cattle occurred between 1991 and 1993, with at least 47 animals shot in 3 weeks in February 1991, a further two in March–April 1991, and two in December 1991–January 1992. The only two surviving animals were removed alive in February 1993 for captive breeding. The ecological response is considered significant but unable to be completely differentiated from the effects of subsequent eradication of rabbits and mice. Attempts to preserve genetic material via ova, sperm, and live animals met with limited initial success but a small captive population has been established on mainland New Zealand.
{"title":"The eradication of cattle from Enderby Island and subsequent ecological response","authors":"Derek Brown, Finlay Cox","doi":"10.20417/nzjecol.47.3485","DOIUrl":"https://doi.org/10.20417/nzjecol.47.3485","url":null,"abstract":": Cattle ( Bos taurus ) were liberated on 695 ha Enderby Island, the northernmost of the Auckland Island group, in 1894–96, after a previous liberation had died out. After reaching a peak population of c. 100 animals, they established a relatively stable population of 35–60 animals for the latter half of the 20th century. Eradication was mandated in the 1987 Auckland Islands Management Plan, but proposals for eradication were not universally supported due to the interesting traits of this long-isolated population and its adaptation to the subantarctic environment of the island. Therefore, retrieval of genetic material was permitted before the planned operation. Eradication of the cattle occurred between 1991 and 1993, with at least 47 animals shot in 3 weeks in February 1991, a further two in March–April 1991, and two in December 1991–January 1992. The only two surviving animals were removed alive in February 1993 for captive breeding. The ecological response is considered significant but unable to be completely differentiated from the effects of subsequent eradication of rabbits and mice. Attempts to preserve genetic material via ova, sperm, and live animals met with limited initial success but a small captive population has been established on mainland New Zealand.","PeriodicalId":49755,"journal":{"name":"New Zealand Journal of Ecology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46253704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","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：