Drone view of a Black-browed Albatross colony on Steeple Jason Island in the South Atlantic, photograph from Sarah Crofts

Madeline Hayes (University Marine Laboratory, Beaufort, North Carolina, USA) and colleagues have published in the journal Ornithological Applications on counting breeding Black-browed Albatrosses Thalassarche melanophris from drone imagery.

The paper’s abstract follows:

“Population monitoring of colonial seabirds is often complicated by the large size of colonies, remote locations, and close inter- and intra-species aggregation. While drones have been successfully used to monitor large inaccessible colonies, the vast amount of imagery collected introduces a data analysis bottleneck. Convolutional neural networks (CNN) are evolving as a prominent means for object detection and can be applied to drone imagery for population monitoring. In this study, we explored the use of these technologies to increase capabilities for seabird monitoring by using CNNs to detect and enumerate Black-browed Albatrosses (Thalassarche melanophris) and Southern Rockhopper Penguins (Eudyptes c. chrysocome) at one of their largest breeding colonies, the Falkland (Malvinas) Islands. Our results showed that these techniques have great potential for seabird monitoring at significant and spatially complex colonies, producing accuracies of correctly detecting and counting birds at 97.66% (Black-browed Albatrosses) and 87.16% (Southern Rockhopper Penguins), with 90% of automated counts being within 5% of manual counts from imagery. The results of this study indicate CNN methods are a viable population assessment tool, providing opportunities to reduce manual labor, cost, and human error.”

Resumen: El monitoreo de las poblaciones de aves marinas coloniales es usualmente complicado por el gran tamaño de las colonias, los lugares remotos y la agregación densa inter- e intra-específica. Mientras que los drones han sido usados exitosamente para monitorear grandes colonias inaccesibles, la gran cantidad de imágenes colectadas introduce un cuello de botella en el análisis de los datos. Las redes neuronales convolucionales (RNC) están evolucionando como un medio prominente para la detección de objetos y pueden ser aplicadas a las imágenes de drones para el monitoreo poblacional. En este estudio, exploramos el uso de estas tecnologías para aumentar la capacidad de monitoreo de las aves silvestres mediante el uso de RNC para detectar y contar a Thalassarche melanophris y Eudyptes c. chrysocome en una de sus colonias de cría más grandes, las Islas Malvinas. Nuestros resultados mostraron que estas técnicas tienen gran potencial para el monitoreo de aves marinas en colonias significativas y espacialmente complejas, produciendo precisiones para detectar y contar correctamente las aves en un 97.66% (T. melanophris) y 87.16% (E. c. chrysocome), con un 90% de los conteos automáticos estando dentro del 5% de los conteos manuales realizados a partir de las imágenes. Los resultados de este estudio indican que los métodos de RNC son una herramienta viable de evaluación poblacional, brindando oportunidades para reducir el trabajo manual, el costo y el error humano.

Reference:

Hayes, M.C., Gray, P.C., Harris, G., Sedgwick, W.C., Crawford, V.D., Chazal, N., Crofts, S. & Johnston, D.W. 2021. Drones and deep learning produce accurate and efficient monitoring of large-scale seabird colonies.  Ornithological Applications  doi.org/10.1093/ornithapp/duab022.

John Cooper, ACAP Information Officer, 05 June 2021

"Albatross", artwork by Anne Shoemaker

Alice Bernard (CEFE, Univ. Montpellier, France) and colleagues have published open access in the journal Conservation Letters on developing a a global strategy for tracking seabirds at sea.  “Unbiased tracking of the world's seabirds is essential for understanding their ecology and of the impacts of environmental changes on their population trajectories.  It is therefore key to seabird conservation in a changing world, as well as for understanding global marine ecosystem dynamics, for marine spatial planning and the design and efficiency of marine protected area networks.”

The paper’s abstract follows:

“Electronic tracking technologies revolutionized wildlife ecology, notably for studying the movements of elusive species such as seabirds. Those advances are key to seabird conservation, for example in guiding the design of marine protected areas for this highly threatened group. Tracking data are also boosting scientific understanding of marine ecosystem dynamics in the context of global change. To optimize future tracking efforts, we performed a global assessment of seabird tracking data. We identified and mined 689 seabird last four decades. We found substantial knowledge gaps, reflecting a historical neglect of tropical seabird ecology, with biases toward species that are heavier, oceanic, and from high-latitude regions. Conservation status had little influence on seabird tracking propensity. We identified 54 threatened species for which we did not find published tracking records, and 19 with very little data. Additionally, much of the existing tracking data are not yet available to other researchers and decision-makers in online databases. We highlight priority species and regions for future tracking efforts. More broadly, we provide guidance toward an ethical, rational, and efficient global tracking program for seabirds, as a contribution to their conservation.”

Reference:

Bernard, A., Rodrigues, AS.L., Cazalis, V. & Grémillet, D. 2021.  Toward a global strategy for seabird tracking.  Conservation Letters doi.org/10.1111/conl.12804.

John Cooper, ACAP Information Officer, 04 June 2021

Moving to safety from a landing helicopter.  Keith Springer cradles an Antipodean Albatross chick on Antipodes Island

Following the interviewing of shortlisted candidates last month for the position of Operations Manager, the Mouse-Free Marion Project is pleased to announce that Mr Keith Springer of New Zealand has been offered and has accepted the post to rid South Africa’s sub-Antarctic Marion Island of its predatory House Mice that have taken to attacking and killing surface-breeding albatrosses.

With a career that had its early days with New Zealand’s Department of Conservation, Antarctica New Zealand and the Tasmania Parks and Wildlife Service, Keith has considerable experience in island rodent eradication operations and is one of the world leaders in the field.  He led the successful (and award-winning) operation to eradicate European Rabbits, Black Rats and House Mice from Australia’s Macquarie Island, was part of the South Georgia Heritage Trust’s Habitat Restoration Project team that successfully eradicated Brown Rats and House Mice from South Georgia (Islas Georgias del Sur)* and has served as an advisor on many other rodent-eradication projects.  These have included being Operational Advisor and Safety Officer to the successful “Million Dollar Mouse” eradication on Antipodes Island and Operations Planner for the Gough Island Restoration Programme that aims to eradicate that island’s mice from June to September this year.  He was also responsible for the development of draft Operational and Project Plans for the Mouse-Free Marion Project on behalf of the environmental NGO BirdLife South Africa, having visited the island for this purpose in 2018.

Keith writes to ACAP Latest News: “What motivates me to be involved in island pest eradication projects is the chance to contribute to shifting the ecological balance back to species native to the island.  Seabirds are a particular beneficiary of predator removal, and they face so many issues off-island that they really do not need the added pressure of being “chomped on” when back on home turf.  But vegetation, soil and invertebrates also improve with invasive predators removed, so there is no doubt that it is a whole-of-ecosystem response when predators are removed.  My core motivation therefore is to plan operations to enhance the likelihood of a successful eradication outcome.”  He also notes that albatrosses, including those at risk to Gough and Marion’s mice “already face so many threats at sea.  On some of the islands they breed on, they face existential threats from introduced predators as well, so the populations are getting squeezed from both land and sea.  Without actions to reduce fishing mortality and introduced predators on their breeding islands, we face the sad but very real possibility of a world without albatrosses.”

Keith is due to start with MFM in July, although for the first month he will also be involved with follow-up work on Australia’s Lord Howe Island where the Rodent Eradication Project  was carried out in 2019.  He will be based in New Zealand with regular trips to South Africa, and to Marion Island as well.

 ACAP’s Information Officer first met Keith Springer in the ACAP Secretariat offices in Hobart, Tasmania when he was in the early stages of executing the Macquarie Island Pest Eradication Project (MIPEP) for the Tasmania Parks and Wildlife Service.  Their conversation included the issue of mice on Marion – some years before the first reports of attacks on albatrosses.  Subsequently, regular posts to ACAP Latest News allowed readers to follow the fortunes of the Macquarie Island eradication effort to its ultimate success. Now, quite some years later, Keith will be bringing the knowledge and skills he learnt on “Macca” and honed elsewhere to rid Marion of its “killer” mice.

A number of applications has been received for the position of MFM Communications Manager. These have been assessed, and interviews will be arranged once the Project Manager returns from Gough Island later this month.

With thanks to Keith Springer and Anton Wolfaardt, Project Manager, Mouse-Free Marion Project.

John Cooper, ACAP Information Officer, 03 June 2021

*A dispute exists between the Governments of Argentina and the United Kingdom of Great Britain and Northern Ireland concerning sovereignty over the Falkland Islands (Islas Malvinas), South Georgia and the South Sandwich Islands (Islas Georgias del Sur y Islas Sandwich del Sur) and the surrounding maritime areas.

Streaked Shearwater at sea

 Shiho Koyama (Graduate School of Environmental Studies, Nagoya University, Japan) and colleagues have published in the journal of Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology on  foraging stress in Streaked Shearwaters Calonectris leucomelas rearing chicks

The paper’s abstract follows:

“To understand foraging strategies and behavioral flexibility in wild animals, it is important to evaluate the physiological costs imposed by foraging efforts and how these costs affect foraging and provisioning behavior. Oxidative stress is a possible physiological indicator associated with foraging behavior in wild seabirds, and may also affect their reproductive performance. However, no previous study has simultaneously recorded foraging behavior and the associated oxidative stress in wild seabirds. Using an integrative approach based on oxidative stress measurements and bio-logging techniques (i.e., the use of animal-borne sensors), we determined the relationships between foraging behavior and oxidative stress in chick-rearing streaked shearwaters Calonectris leucomelas in 2018 and 2019. To quantify their oxidative stress, we measured reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP) in their plasma. We found that the d-ROMs levels were positively related to the maximum distance from the colony and the number of takeoffs, especially in 2019 when shearwaters flew further to forage. In 2018, when they flew relatively short distances, the BAP levels were positively related to the levels of their physical activity (overall dynamic body acceleration; ODBA). We conclude that longer and less successful foraging may lead to increase oxidative stress, while successful foraging may mitigate the oxidative stress of foraging by providing dietary antioxidants. Our results highlight that the combined data from bio-logging and oxidative stress measurements aid in evaluating the underlying physiological costs of foraging behavior in wild animals.”

Reference:

Koyama S., Mizutani, Y. & Yoda, K. 2021.  Exhausted with foraging: foraging behavior is related to oxidative stress in chick-rearing seabirds.  Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology doi.org/10.1016/j.cbpa.2021.110984.

John Cooper, ACAP Information Officer, 02 June 2021