Context. Aerial application of poison bait pellets is an established and widely used method for removing invasive rodents and restoring insular ecological processes. However, the non-target effects of saturation poisoning require very careful consideration and precautionary risk-avoidance strategies. Aims. We assessed the risk of primary and secondary poisoning by rodenticides to terrestrially foraging lesser sheathbills (Chionis minor marionensis), Gough moorhens (Gallinula comeri) and Gough buntings (Rowettia goughensis) at Marion and Gough Islands. Methods. Birds taken into temporary captivity were offered non-toxic bait pellets dyed different colours and the carcasses of house mice (Mus musculus). In addition, dead mice were offered to these three species in the field, as well as to sub-Antarctic skuas (Catharacta antarctica) at both islands. Response to captivity was assessed by daily weighings. Key results. Individual birds either gained or lost mass overall during their 4–7 days in captivity. Whereas all captive birds pecked at the pellets, minimal amounts were consumed. However, Gough moorhens offered pellets in the field did consume them. Sheathbills (in captivity and in the field) and moorhens (in the field) consumed mouse carcasses, whereas buntings in captivity ate little from them. Sub-Antarctic skuas offered mouse carcasses in the field at both islands readily consumed them. At Gough Island some, but not all, skuas consumed bait in the field. Conclusions. Although the levels of assessed risk to primary and secondary poisoning differed among the three main species studied, it is recommended that populations for subsequent reintroduction be taken into temporary captivity before and during a poison-bait exercise as a precautionary measure. It is not deemed necessary to take sub-Antarctic skuas into captivity because they will be largely absent during a poisoning exercise in winter (the most likely period). Implications. Captive studies to assess susceptibility to primary and secondary poisoning are useful for determining positive risk; however, cage effects can cause false negatives by altering behaviours, and should be conducted with complimentary field trials. Where endemic species show any degree of risk (e.g. are vulnerable to the poison, regardless of how it might be ingested), precaution dictates that the risk be mitigated.
Predation by introduced house mice Mus musculus on islands is one cause of decline in native birds and has deleterious impacts on other ecological aspects. Eradication of rats (Rattus spp.) from islands of up to >10000 ha has been achieved, but for mice scale is still an issue with the largest island cleared being only 710 ha. The feasibility of eradicating mice from larger islands is being considered, and to support these assessments, we undertook a field study on Gough Island (6400 ha) to determine whether all mice would be likely to accept toxic bait. We replicated a toxic bait operation as closely as possible, in timing, probable bait density and distribution, using a bait formulation used commonly in rodent eradication operations. Baits lacked toxin but were coated with the fluorescent dye rhodamine B. Mice trapped in and around the baited areas were inspected under ultraviolet light for fluorescent marking indicative of bait consumption. Of 434 mice, 97% tested positive, including mice trapped on assessment lines up to 90 m from the closest bait. There was no difference in the proportions of unstained mice from assessment lines outside baited sites compared with mice trapped in the core baited sites, suggesting large-scale foraging movements over relatively large distances into the baited sites from surrounding, non-baited habitat. Despite the high bait densities (15.7 kg ha−1 at initial application and 7.9 kg ha−1 at second application), bait consumption rates of ~4 kg ha−1 day−1 occurred after both applications. This was much higher than expected (probably the result of large-scale movements) and meant that all baits were consumed before trapping began. Thus the 13 unstained mice trapped in the core of the baited area may have moved there after bait was consumed. Further trials are required to assess whether all unmarked mice were false negatives (not exposed to bait) or if any were true negatives (rejected bait). A separate experiment found that all 11 mice trapped in a cave had eaten bait applied aboveground around the cave's entrances, suggesting that caves do not serve as refugia for mice and are thus unlikely to compromise an eradication attempt.
Este artículo contiene 27 páginas, 2 tablas, 5 figuras. ; Shearwaters and petrels (hereafter petrels) are highly adapted seabirds that occur across all the world's oceans. Petrels are a threatened seabird group comprising 124 species. They have bet-hedging life histories typified by extended chick rearing periods, low fecundity, high adult survival, strong philopatry, monogamy and long-term mate fidelity and are thus vulnerable to change. Anthropogenic alterations on land and at sea have led to a poor conservation status of many petrels with 52 (42%) threatened species based on IUCN criteria and 65 (52%) suffering population declines. Some species are well-studied, even being used as bioindicators of ocean health, yet for others there are major knowledge gaps regarding their breeding grounds, migratory areas or other key aspects of their biology and ecology. We assembled 38 petrel conservation researchers to summarize information regarding the most important threats according to the IUCN Red List of threatened species to identify knowledge gaps that must be filled to improve conservation and management of petrels. We highlight research advances on the main threats for petrels (invasive species at breeding grounds, bycatch, overfishing, light pollution, climate change, and pollution). We propose an ambitious goal to reverse at least some of these six main threats, through active efforts such as restoring island habitats (e.g., invasive species removal, control and prevention), improving policies and regulations at global and regional levels, and engaging local communities in conservation efforts. ; AR and FR were supported by Juan de la Cierva programme, Spanish Ministry of Economy, Industry and Competitiveness (IJCI-2015-23913 and IJCI-2015-24531). ML was funded by the Ramón y Cajal programme (RYC-2012-09897), Spanish Ministry of Economy, Industry and Competitiveness. WM was supported by an NSERC Discovery grant. MG was partially supported by the European Union (MINOUW Project, H2020-634495). JMA and VC were supported by ZEPAMED Project, Pleamar programme, Fundación Biodiversidad, Spanish Ministry of Ecological Transition. ; Peer reviewed
Migratory marine species cross political borders and enter the high seas, where the lack of an effective global management framework for biodiversity leaves them vulnerable to threats. Here, we combine 10,108 tracks from 5775 individual birds at 87 sites with data on breeding population sizes to estimate the relative year-round importance of national jurisdictions and high seas areas for 39 species of albatrosses and large petrels. Populations from every country made extensive use of the high seas, indicating the stake each country has in the management of biodiversity in international waters. We quantified the links among national populations of these threatened seabirds and the regional fisheries management organizations (RFMOs) which regulate fishing in the high seas. This work makes explicit the relative responsibilities that each country and RFMO has for the management of shared biodiversity, providing invaluable information for the conservation and management of migratory species in the marine realm. ; This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under the Marie Skłodowska-Curie grant agreement no. 766417. Research made possible with the support, permissions, and funding granted by the following organizations, institutions, and grant agreements: Marine Conservation Program of DPIPWE Tasmania; American Bird Conservancy; Bureau of Ocean Energy Management; communities of Isla Mocha and Islas Juan Fernández; Corporación Nacional Forestal and Servicio Agrícola y Ganadería (Chile); Environment Canada; the National Fish and Wildlife Foundation; the National Geographic Society; ProDelphinus; and the Wallis Foundation; NSF grants DEB 9304579, DEB 9629539, DEB9806606, DEB0235818, and DEB 0842199 to D.J.A.; the National Geographic Society; the U.S. Fish and Wildlife Service; U.S. Geological Survey Ecosystems Mission Area, Wake Forest University; Max-Planck Society and State of Baden-Wuerttemberg Innovation funding; Colorado State University International Programs; Swiss Friends of Galapagos; the International Center for Tropical Ecology at University of Missouri-St. Louis; the Instituto Antartico Chileno (INACH) and the Australian Antarctic Division (AAD); LIFE "Marine IBAs IN Spain" (LIFE04NAT/ES/000049, 2004-2009) and LIFE+ INDEMARES (2009-2014); Sea World Research and Rescue Foundation Inc.; Holsworth Wildlife Research Endowment; and Winifred Violet Scott Trust; FCT-Portugal through projects (UIDB/04292/2020 and UIDP/04292/2020 and UIDP/50017/2020 and UIDB/50017/2020, granted to MARE and CESAM, respectively); the Falklands Islands Government; Natural Environmental Research Council (NERC) core funding to British Antarctic Survey Ecosystems Programme and Official Development Assistance Atlantic Islands project (NE/ R000 107/1); the New Zealand Department of Conservation; Ministry for Primary Industries; Ngāti Rehua Ngāti Wai ki Aotea; Falklands Island Conservation; University of Barcelona (APIF/2015, to M.C.-F.); the French Polar Institute (program IPEV n°109 to H.W.); Réserve Naturelle Nationale des Terres Australes Françaises; and the Zones Atelier Antarctique (LTSER France, CNRS-INEE); European funds through the European Commission Training and Mobility of Researchers Programme (ERBFMBICT983030); Spanish funds through the Ministerio de Ciencia y Tecnología (REN2002-01164/GLO), Ministerio de Educación y Ciencia (CGL2006-01315/BOS), Ministerio de Ciencia e Innovación (CGL2009-11278/BOS), and Ministerio de Economía y Competitividad (CGL2013-42585-P); Catalan funds through the Generalitat de Catalunya (2001SGR00091); and additional funding from SEO/BirdLife (programa Migra & proyecto LIFE+ Indemares), Fundación Banco Bilbao Vizcaya Argentaria (BIOCON04/099) and Fundación Biodiversidad (18PCA4328, 2012-2013); NSERC Discovery Grant and Government of Canada's Program for International Polar Year to W.A.M.; and an ACAP AC Grant in 2013-14, predoctoral contract BES-2017-079874 of the Spanish Ministerio de Industria, Economía y Competitividad (to L.N.-H.); Spanish Foundation for Biodiversity and Spanish Ministry of Science grant ref. CGL2013-42203-R; the Pew Environment Group via the Pew Fellowship Award in Marine Conservation (to M.L.C.); National Research Foundation; South Africa and Oceans and Coasts; Department of Environment, Agriculture and Fisheries; Malta Seabird Project (LIFE10NAT/MT/090) co-funded by the LIFE program of the European Commission and the Maltese Ministry for the Environment, Sustainable Development and Climate Change, in partnership with the Royal Society for the Protection of Bird and the Portuguese Society for the Study of Birds; predoctoral contract BES-2014-068025 of the Spanish Ministerio de Industria, Economía y Competitividad (to V.M.-P.); Scientific Expert PIM initiative (Petites Iles de Méditerranée); the PIM initiative (Petites Iles de Méditerranée); the Tunisian Coastal Protection and Planning Agency (APAL); Ministry of the Environment, Japan; Funding by Fundación Ecocentro, Argentina; Wildlife Conservation Society, USA; and Ministerio de Ciencia, Tecnología e Innovación, Argentina; Centro Nacional Patagónico (CONICET), postdoctoral contracts by Beatriu de Pinós (2010-BP_A-00173), Juan de la Cierva (JCI-2009-05426), PLEAMAR (2017/2349), and Ramón y Cajal (RYC-2017-22055) programme (to R.R.); Seventh Framework Programme (Research Executive Agency of the European Commission, 618841, FP7-PEOPLE-2013-CIG); Fondation Total pour la Biodiversité (project: Trophic ecology and impacts of bycatch on the avifauna communities of Zembra archipelago); Agence de Protection et d'Aménagement du Littoral (APAL-Tunisia); Killam Postdoctoral fellowship from Dalhousie University; South African National Antarctic Programme; ACAP; Papahānaumokuākea Marine National Monument; NOAA; Japan Society for the Promotion of Science Kakenhi grant 19651100 and 15H02857; National Parks and Conservation Service (Mauritius) (to M.L.C.); IPEV Prog 109; and NASA. The use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. government. The scientific results and conclusions, as well as any views or opinions expressed herein, are those of the authors and do not necessarily reflect those of the NOAA or the Department of Commerce. This communication reflects only the authors' view, and the Research Executive Agency of the European Union is not responsible for any use that may be made of the information it contains. Z.Z. acknowledges funding from a predoctoral grant (APIF/2012) from the University of Barcelona. J.Ad. acknowledges funding from the U.S. Geological Survey Ecosystems Mission Area, U.S. Bureau of Ocean Energy Management, Pacific OCS Region.
Migratory marine species cross political borders and enter the high seas, where the lack of an effective global management framework for biodiversity leaves them vulnerable to threats. Here, we combine 10,108 tracks from 5775 individual birds at 87 sites with data on breeding population sizes to estimate the relative year-round importance of national jurisdictions and high seas areas for 39 species of albatrosses and large petrels. Populations from every country made extensive use of the high seas, indicating the stake each country has in the management of biodiversity in international waters. We quantified the links among national populations of these threatened seabirds and the regional fisheries management organizations (RFMOs) which regulate fishing in the high seas. This work makes explicit the relative responsibilities that each country and RFMO has for the management of shared biodiversity, providing invaluable information for the conservation and management of migratory species in the marine realm.
