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A 31-Year Time Series Of At-Sea Counts Shows A Non-Significant Decline Of Marbled Murrelets At Laskeek Bay, Haida Gwaii, 1990–2020, Vivian Pattison, Douglas F. Bertram, Sonya A. Pastran, Anthony J. Gaston, Rian D. Dickson, Mark C. Drever Jul 2025

A 31-Year Time Series Of At-Sea Counts Shows A Non-Significant Decline Of Marbled Murrelets At Laskeek Bay, Haida Gwaii, 1990–2020, Vivian Pattison, Douglas F. Bertram, Sonya A. Pastran, Anthony J. Gaston, Rian D. Dickson, Mark C. Drever

Marine Ornithology

The Marbled Murrelet Brachyramphus marmoratus breeds and overwinters along the coast of British Columbia, Canada, and is listed as Threatened under the Canadian Species at Risk Act. Understanding population trends for this seabird species is important for management and recovery, yet long-term time-series data for Marbled Murrelet abundance are rare. We update trends and annual fluctuations of Marbled Murrelet numbers derived from at-sea counts in Laskeek Bay, Haida Gwaii, on the north coast of British Columbia, 1990–2020. We found a non-significant negative trend (−1.55% per year). Counts varied seasonally and peaked in early June; counts also varied with distance from …

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Finding Colonies Of Black-Headed Gulls Chroicocephalus Ridibundus Using Google Earth, Roberto G. Valle, Alejandro Corregidor-Castro, Francesco Scarton Jul 2025

Finding Colonies Of Black-Headed Gulls Chroicocephalus Ridibundus Using Google Earth, Roberto G. Valle, Alejandro Corregidor-Castro, Francesco Scarton

Marine Ornithology

We explore the possibility of identifying Black-headed Gull Chroicocephalus ridibundus colonies in the saltmarshes of the Lagoon of Venice, Italy, using Google Earth satellite images. One reproductive season was considered (June 2017), based on the images available on Google Earth. This species builds nests clustered around tidal pools and tidal creeks, providing a dark background to reveal the white gulls. Images of the southern part of the lagoon (excluding fish farms) were analyzed by dividing it into sectors (n = 403) using the Google Earth grid at an elevation of 100 m above ground level. The results of the satellite …

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Status And Occurrence Of Wedge-Tailed Shearwater Ardenna Pacifica In Waters Of The Northwestern Coast Of South America, Manuel Marín Jul 2025

Status And Occurrence Of Wedge-Tailed Shearwater Ardenna Pacifica In Waters Of The Northwestern Coast Of South America, Manuel Marín

Marine Ornithology

This study examines the distribution of Wedge-tailed Shearwater Ardenna pacifica along the northwest coast of South America. The species is well known in tropical waters distant from the coast, but it also appears to be a regular visitor to shelf-break waters off Colombia and northern Ecuador; there is no evidence indicating a similar presence within the exclusive economic zone (EEZ) of Peru, where waters are colder. About 50% of Wedge-tailed Shearwater sightings are associated with dolphins and/or large fish. More than 90% of the nearshore South American records are of pale-phase individuals.

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Tracked Gulls Help Identify Potential Zones Of Interaction Between Whales And Shipping Traffic, Megan A. Cimino, Heather Welch, Jarrod A. Santora, David Kroodsma, Elliott L. Hazen, Steven J. Bograd, Pete Warzybok, Jaime Jahncke, Scott A. Shaffer Jul 2025

Tracked Gulls Help Identify Potential Zones Of Interaction Between Whales And Shipping Traffic, Megan A. Cimino, Heather Welch, Jarrod A. Santora, David Kroodsma, Elliott L. Hazen, Steven J. Bograd, Pete Warzybok, Jaime Jahncke, Scott A. Shaffer

Marine Ornithology

Seabird-vessel interactions are often studied through the lens of fisheries bycatch, but seabirds encounter many watercraft types. Western Gulls Larus occidentalis breeding on the Farallon Islands (California, USA) have a foraging domain that encompasses both shipping lanes and productive fishing grounds, resulting in ample opportunities for vessel encounters. Previous research showed that these Western Gulls can serve as ecosystem indicators because their foraging behavior is linked to ocean prey conditions, and because their foraging grounds overlap with that of Humpback Whales Megaptera novaeangliae, which can make prey accessible. Because ship strikes and entanglement in fishing gear are concerns for whales …

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Insights Into The Ecology And Conservation Of Coastal Brazil Seabirds Based On Band Returns, Henrique Chupil, Rosane Fernanda Farah, Andrea Maranho, Carla Beatriz Barbosa, Simone Leonardi, Juarez Cabral, Jenyffer Vierheller Vieira, Liana Rosa, Rodrigo Del Rio Do Valle Jul 2025

Insights Into The Ecology And Conservation Of Coastal Brazil Seabirds Based On Band Returns, Henrique Chupil, Rosane Fernanda Farah, Andrea Maranho, Carla Beatriz Barbosa, Simone Leonardi, Juarez Cabral, Jenyffer Vierheller Vieira, Liana Rosa, Rodrigo Del Rio Do Valle

Marine Ornithology

Banding is the main method used to mark and identify individual birds, and to study populations, migration, age, and behavior. Banding birds also plays an important role in rehabilitation efforts, as their recapture provides good information about the effectiveness of the prescribed treatment, allowing constant review of the rehabilitation protocols used. This study compiles information on banded birds retrieved at the Santos Basin Beach Monitoring Project (Projeto de Monitoramento de Praias da Bacia de Santos, PMP-BS), and it reviews the ecological and behavioral aspects involved in species’ movements that contributed to their arrival at the beach. We also provide results …

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Autumn Marine Bird Populations In Queen Charlotte Strait And Adjacent Waters: A Candidate For Iba/Kba Status, Anthony J. Gaston, Mark Maftei, Sonya A. Pastran Jul 2025

Autumn Marine Bird Populations In Queen Charlotte Strait And Adjacent Waters: A Candidate For Iba/Kba Status, Anthony J. Gaston, Mark Maftei, Sonya A. Pastran

Marine Ornithology

Systematic transect surveys of marine birds in eastern Queen Charlotte Strait and the western part of Johnstone Strait, British Columbia, Canada, were made between mid-August and mid-October 2020–2022. All birds within 100-m transect strips were counted and numbers corrected for detectability. Extrapolating within five regions of differing ecological characteristics and seabird densities, our results indicate that the study area supported 1% or more of the North American populations of Pigeon Guillemot Cepphus columba, Marbled Murrelet Brachyramphus marmoratus, California Gull Larus californicus, Glaucous-winged Gull L. glaucescens, Iceland Gull L. glaucoides, and Short-billed Gull L. brachyrhynchos. Our estimation of gull species in …

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Reviews: Chasing The Sun (Musso, T.); New(Ish) And Noteworthy: Ocean Bestiary: Meeting Marine Life From Abalone To Orca To Zooplankton (King, R.J.); Flight Paths: How A Passionate And Quirky Group Of Pioneering Scientists Solved The Mystery Of Bird Migration (Heisman, R.); Nonviolent Communication: A Language Of Life, 3rd Edition (Rosenberg, M. B.); The Home Place: Memoirs Of A Colored Man's Love Affair With Nature (Lanham, J.D.), David C. Duffy, Eric Wagner Jul 2025

Reviews: Chasing The Sun (Musso, T.); New(Ish) And Noteworthy: Ocean Bestiary: Meeting Marine Life From Abalone To Orca To Zooplankton (King, R.J.); Flight Paths: How A Passionate And Quirky Group Of Pioneering Scientists Solved The Mystery Of Bird Migration (Heisman, R.); Nonviolent Communication: A Language Of Life, 3rd Edition (Rosenberg, M. B.); The Home Place: Memoirs Of A Colored Man's Love Affair With Nature (Lanham, J.D.), David C. Duffy, Eric Wagner

Marine Ornithology

No abstract provided.

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Best Practices For Using Drones In Seabird Monitoring And Research, Alice J. Edney, Tom Hart, Mark J. Jessopp, Alex Banks, Lucy E. Clarke, Laure Cugnière, Kyle H. Elliot, Ignacio Juarez Martinez, Alexandra Kilcoyne, Matthew Murphy, Ruedi G. Nager, Norman Ratcliffe, Danielle L. Thompson, Robin M. Ward, Matt J. Wood Jul 2025

Best Practices For Using Drones In Seabird Monitoring And Research, Alice J. Edney, Tom Hart, Mark J. Jessopp, Alex Banks, Lucy E. Clarke, Laure Cugnière, Kyle H. Elliot, Ignacio Juarez Martinez, Alexandra Kilcoyne, Matthew Murphy, Ruedi G. Nager, Norman Ratcliffe, Danielle L. Thompson, Robin M. Ward, Matt J. Wood

Marine Ornithology

Over the past decade, drones have become increasingly popular in environmental biology and have been used to study wildlife on all continents. Drones have become of global importance for surveying breeding seabirds by providing opportunities to transform monitoring techniques and allow new research on some of the most threatened birds. However, such fast-changing and increasingly available technology presents challenges to regulators responding to requests to carry out surveys and to researchers ensuring their work follows best practices and meets legal and ethical standards. Following a workshop convened at the 14th International Seabird Group Conference and a subsequent literature search, we …

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Oiling Threats To Marine Birds On Southern Vancouver Island, British Columbia, Canada, Douglas F. Bertram, Patrick D. O’Hara, Alexandra M. King, Clifford L.K. Robinson, Mark Maftei, Kerry J. Woo Jul 2025

Oiling Threats To Marine Birds On Southern Vancouver Island, British Columbia, Canada, Douglas F. Bertram, Patrick D. O’Hara, Alexandra M. King, Clifford L.K. Robinson, Mark Maftei, Kerry J. Woo

Marine Ornithology

Information on the distribution and abundance of marine birds is needed to evaluate current status in relation to threats from potential increases in vessel traffic off southern Vancouver Island, British Columbia (BC), Canada, in the Salish Sea. We conducted year-round boat based surveys in waters between Sidney, BC and Victoria, BC from November 2015 to August 2019 and examined seasonal variation in bird distribution and abundance. Our study area included parts of the Sidney Channel Important Bird Area, the Shoal Harbour and Victoria Harbour Migratory Bird Sanctuaries, and the Chain Islets Ecological Reserve, adjacent to major shipping lanes, as well …

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Medical History And Post-Release Survival Of Rehabilitated California Brown Pelicans Pelecanus Occidentalis Californicus, 2009-2019, Rebecca S. Duerr, Deborah L. Jaques, Barton G. Selby, Julie S. Skoglund, Suzanne Kosina Jul 2025

Medical History And Post-Release Survival Of Rehabilitated California Brown Pelicans Pelecanus Occidentalis Californicus, 2009-2019, Rebecca S. Duerr, Deborah L. Jaques, Barton G. Selby, Julie S. Skoglund, Suzanne Kosina

Marine Ornithology

California Brown Pelicans Pelecanus occidentalis californicus rehabilitated in 2009–2019 were released with metal federal and blue plastic auxiliary leg bands. Resighting data were obtained from the US Geological Survey’s Bird Banding Laboratory, International Bird Rescue’s citizen science reporting forms, and non-breeding communal roost site surveys. Medical problems and demographic data were assessed in relation to whether birds were resighted, whether they were alive at the most recent resighting, and by longevity after release. The 1418 blue-banded individuals in the study were admitted for rehabilitation and released 1 465 times, and 49.9% were resighted at least once. At the most recent …

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Characterizing The Diet Of A Threatened Seabird, The Marbled Murrelet Brachyramphus Marmoratus, Using High-Throughput Sequencing, Emily D. Fountain, Paige J. Kulzer, Richard T. Golightly, James W. Rivers, Scott F. Pearson, Martin G. Raphael, Matthew G. Betts, S. Kim Nelson, Daniel D. Roby, Nicholas F. Kryshak, Stephanie Schneider, M. Zachariah Peery Jul 2025

Characterizing The Diet Of A Threatened Seabird, The Marbled Murrelet Brachyramphus Marmoratus, Using High-Throughput Sequencing, Emily D. Fountain, Paige J. Kulzer, Richard T. Golightly, James W. Rivers, Scott F. Pearson, Martin G. Raphael, Matthew G. Betts, S. Kim Nelson, Daniel D. Roby, Nicholas F. Kryshak, Stephanie Schneider, M. Zachariah Peery

Marine Ornithology

Understanding prey consumption patterns is critical to understanding the ways in which seabirds cope with a changing ocean. However, characterizing the dietary habitats of seabirds can be challenging. In this study, we investigated the diet of the Marbled Murrelet Brachyramphus marmoratus population that lives in waters off California, Oregon, and Washington, USA, using fecal DNA, custom metabarcoding, and high-throughput sequencing. Murrelets were captured at sea by dip-netting at night. Across this region, murrelets consumed highly diverse prey types including 17 fish species and 10 invertebrate species, in accord with previous work indicating the species’ forage on a wide range of …

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Stable Isotope-Determined Diets Of Black Oystercatchers Haematopus Bachmani In The Northern Gulf Of Alaska, Brooke Carney, David Tessler, Heather Coletti, Jeffrey M. Welker, Douglas Causey Jul 2025

Stable Isotope-Determined Diets Of Black Oystercatchers Haematopus Bachmani In The Northern Gulf Of Alaska, Brooke Carney, David Tessler, Heather Coletti, Jeffrey M. Welker, Douglas Causey

Marine Ornithology

Black Oystercatchers Haematopus bachmani (BLOY) feed on intertidal invertebrates along coasts of the northern Gulf of Alaska and elsewhere. Details of their feeding ecology have only been marginally delineated, however, and as population sizes are small and limited geographically, rapid ecological changes may alter their prey base, placing BLOY resiliency in jeopardy. We examined the diets of BLOYs occupying the coast at three sites in Southeast Alaska using stable isotope analysis of carbon (δ13C) and nitrogen (δ15N) to answer the following three questions: (1) what are the diet proportions of prey groups consumed at different locations along the northern Gulf …

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Flight Altitudes Of Chick-Rearing Rhinoceros Auklets Cerorhinca Monocerata Measured By Gps Logger, Jumpei Okado, Yutaka Watanuki Jul 2025

Flight Altitudes Of Chick-Rearing Rhinoceros Auklets Cerorhinca Monocerata Measured By Gps Logger, Jumpei Okado, Yutaka Watanuki

Marine Ornithology

Alcids generally fly at low altitudes (below 5 m) over the sea but may occasionally fly higher in certain areas, which may put them at risk of collision with turbine blades in offshore wind farms. We used GPS loggers to investigate the location and altitude of flying Rhinoceros Auklets Cerorhinca monocerata. They typically flew at low altitudes averaging < 1 m but flew higher (> 20 m) when returning the last 5–10 km to their colony, which was located at an elevation of 120–130 m above sea level. Thus, the region over which Rhinoceros Auklets fly highest may vary, depending on the location and elevation of their …

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Sighting Of A Beck's Petrel Pseudobulweria Becki And A Vanuatu Petrel Pterodroma [Cervicalis] Occulta In Remote Oceania, And The Process Of Identification, Robert L. Flood, Kirk Zufelt Jul 2025

Sighting Of A Beck's Petrel Pseudobulweria Becki And A Vanuatu Petrel Pterodroma [Cervicalis] Occulta In Remote Oceania, And The Process Of Identification, Robert L. Flood, Kirk Zufelt

Marine Ornithology

This note reports observations of a presumed Beck’s Petrel Pseudobulweria becki and a Vanuatu Petrel Pterodroma [cervicalis] occulta in April 2022, in the low latitudes of the North Pacific, north of Kiritimati, Republic of Kiribati. The sightings are significant because the ranges of both taxa are barely known and their conservation classifications are concerning. We explain the circumstances of each sighting and the process of identification, reflecting upon current identification criteria and our studies of Beck’s Petrel and Vanuatu Petrel at their breeding grounds. Discussion is illustrated with photographs of each bird and its cryptic confusion counterpart—the larger Tahiti Petrel …

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Increasing Use Of Artificial Nest Chambers By Seasonally Segregated Populations Of Band-Rumped Storm Petrels Hydrobates Castro At St Helena, South Atlantic Ocean, Annalea Beard, Robert J. Thomas, Elizabeth Clingham, Leeann Henry, Renata Medeiros, Steffen Oppel, Alison Small, Frank Hailer Jul 2025

Increasing Use Of Artificial Nest Chambers By Seasonally Segregated Populations Of Band-Rumped Storm Petrels Hydrobates Castro At St Helena, South Atlantic Ocean, Annalea Beard, Robert J. Thomas, Elizabeth Clingham, Leeann Henry, Renata Medeiros, Steffen Oppel, Alison Small, Frank Hailer

Marine Ornithology

Artificial nest chambers have become a common management tool for monitoring nocturnal burrow-nesting seabirds, although their utility varies among species and locations. The widespread Band-rumped Storm Petrel Hydrobates castro species complex potentially harbours a cryptic species endemic to the South Atlantic. Here we evaluate the installation of artificial nest chambers as a tool for long-term conservation and monitoring of this species, which breeds in two distinct seasons on St Helena. Based on six years of observational data, we analysed factors affecting occupancy, mate and chamber fidelity, and reproductive success to optimise nest chamber installation and to enhance future management. Occupancy …

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Apparent Survival Among Adult Leach's Storm Petrels Hydrobates Leucorhous On A Colony Managed For Predators In Nova Scotia, Canada, Sarah E. Gutowsky, Gregory J. Robertson, Anna M. Calvert, David A. Fifield, Robert A. Ronconi, Jennifer C. Rock Jul 2025

Apparent Survival Among Adult Leach's Storm Petrels Hydrobates Leucorhous On A Colony Managed For Predators In Nova Scotia, Canada, Sarah E. Gutowsky, Gregory J. Robertson, Anna M. Calvert, David A. Fifield, Robert A. Ronconi, Jennifer C. Rock

Marine Ornithology

Population declines of Leach’s Storm Petrels Hydrobates leucorhous in the western Atlantic have both led to the species’ recent assessment as Threatened in Canada and contributed to a Vulnerable designation by the IUCN. Limited information suggests low adult survival rates are an important contributing factor. Off eastern Nova Scotia, Canada, Country Island is managed for avian predators and mustelids to protect nesting endangered Roseate Terns Sterna dougallii. The island also hosts a colony of Leach’s Storm Petrels. In 2016, a capture-mark recapture program was initiated for storm petrels, from which we estimated apparent survival and recapture probabilities for 571 breeding …

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Disparate Decadal Trends In Kaua'i Seabird Populations: Possible Effects Of Resource Competition And Anthropogenic Impacts, David Ainley, Stephanie Schneider, Gregory Spencer Jul 2025

Disparate Decadal Trends In Kaua'i Seabird Populations: Possible Effects Of Resource Competition And Anthropogenic Impacts, David Ainley, Stephanie Schneider, Gregory Spencer

Marine Ornithology

Population trends of seabirds nesting on Kaua‘i in the Hawaiian Islands, USA, were assessed across four decades using data from the Save Our Shearwaters (SOS) program. Started in 1979, the SOS database was intended to track the incidence of attraction of Kaua‘i’s seabirds to artificial lights, but recovery rate data also became useful to index population trends. These data documented precipitous declines of Newell’s Shearwater Puffinus newelli through 2017. Here we expand on those efforts by including four additional species and consider data to 2018. All five species exhibited increasing trends during SOS’s first decade, coincidental with increasing human population, …

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When Ornithology Meets Ethnology And Archeology: The Birds Of The Bird-Cult At Rapa Nui (Easter Island) And Their Demise, Manuel Marín Jul 2025

When Ornithology Meets Ethnology And Archeology: The Birds Of The Bird-Cult At Rapa Nui (Easter Island) And Their Demise, Manuel Marín

Marine Ornithology

The disappearance of the bird species involved in the bird-cult of Rapa Nui (Easter Island) was examined. The cult was a contest in which the winner gathered the first seabird egg of the year from a near-shore islet, allowing the winner to become the Tangata Manu, or Birdman. This title provided a heightened status, bringing social and economic benefits and a way of being closer to their gods. Three seabird species were involved in the bird-cult: Great Frigatebird Fregata minor, Sooty Tern Onychoprion fuscatus, and the Spectacled Tern Onychoprion lunatus, none of which currently breed in the area. Rock art …

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The Potential Of Ecologists To Enhance Our Understanding Of Seabird Health, Melanie R. Wells, Annie Philips, Mary-Anne Lea, Scott Carver Jul 2025

The Potential Of Ecologists To Enhance Our Understanding Of Seabird Health, Melanie R. Wells, Annie Philips, Mary-Anne Lea, Scott Carver

Marine Ornithology

Ecologists play a pivotal role in the detection and investigation of population changes in seabirds and by doing so have significant potential to contribute to enhancing knowledge of seabird health. This review highlights key examples in the literature where ecologists have employed diligent passive health surveillance and/or undertaken targeted investigations of seabirds, strategies that have augmented our knowledge of seabird health at individual and population levels. Within the context of One Health, an integrated approach to perceiving and managing health, this review amalgamates veterinarian and ecology disciplines by summarising auxiliary metrics of clinical health that may be considered for incorporation …

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Breeding Parameters Of Yellow-Legged Gull Larus Michahellis In The Largest Moroccan Colony: Natural Versus Urban Nesting Sites, Siham Bellout, Moulay Abdeljalil Ait Baamrane, Mohamed Aourir Jul 2025

Breeding Parameters Of Yellow-Legged Gull Larus Michahellis In The Largest Moroccan Colony: Natural Versus Urban Nesting Sites, Siham Bellout, Moulay Abdeljalil Ait Baamrane, Mohamed Aourir

Marine Ornithology

We investigated the main differences in the breeding ecology of Yellow-legged Gulls Larus michahellis nesting in urban (city of Essaouira) and natural (Mogador Island) environments on the African Atlantic coast of west-central Morocco during the 2018 and 2019 breeding seasons. This Yellow-legged Gull population is the largest in the southern portion of this species’ range, making it excellent for research on the breeding biology of marginal populations. Over two years, we collected data on nest density, chronology, clutch size, egg dimensions, and hatching success from nests across the city and island. Results showed that nest density averaged 1.26 ± 1.03 …

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Nesting Distribution Of Masked Booby Sula Dactylatra At Trindade Island, Western South Atlantic Ocean, Victória R.F. Benemann, Leonardo D. Araújo, Arthur Z. Fabbris, Rosalinda C. Montone, Maria V. Petry Jul 2025

Nesting Distribution Of Masked Booby Sula Dactylatra At Trindade Island, Western South Atlantic Ocean, Victória R.F. Benemann, Leonardo D. Araújo, Arthur Z. Fabbris, Rosalinda C. Montone, Maria V. Petry

Marine Ornithology

The Masked Booby Sula dactylatra is a surface-nesting seabird that breeds on offshore islands across the tropical and subtropical oceans. On inaccessible rocky areas on Trindade Island, located about 1200 km from Espírito Santo, Brazil, the nesting of this species has been poorly studied. To model the species’ nesting habitat suitability at Trindade Island, we mapped active nests during the breeding seasons of 2017 and 2019, from October to November, using a hand-held Global Positioning System receiver and an Unmanned Aerial Vehicle. In order to identify key areas, we created nesting habitat suitability maps using seven different algorithms (Random Forest, …

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Digging In! Burrowing Penguins And Surface Predators, Laura X.L. Tan, Kasun B. Ekanayake, Wouter F.D. Van Dongen, Peter Dann, Duncan R. Sutherland, Michael A. Weston Jul 2025

Digging In! Burrowing Penguins And Surface Predators, Laura X.L. Tan, Kasun B. Ekanayake, Wouter F.D. Van Dongen, Peter Dann, Duncan R. Sutherland, Michael A. Weston

Marine Ornithology

A native Australian corvid, Little Raven Corvus mellori, has emerged as a dominant and problematic predator of an ecologically and economically important seabird, the Little Penguin Eudyptula minor. In 2013, ravens successfully preyed upon clutches/broods of the burrow-nesting penguin, especially those in shallower, more accessible burrows. Individual raven size might mediate which ravens attack penguins; smaller ravens may be able to enter burrows more easily; alternatively, larger ravens may be more capable of overcoming penguin parental defence. Here, we consider the predator-prey interactions to assess whether associations with burrow characteristics persisted and examine whether raven size mediated propensity to prey …

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Seabird Abundance And Distribution Off Western Iberian Waters Estimated Through Aerial Surveys, Hélder Araújo, Pedro Correia-Rodrigues, Jorge Bastos-Santos, Marisa Ferreira, Andreia T. Pereira, Jose Martinez-Cedeira, José Vingada, Catarina Eira Jul 2025

Seabird Abundance And Distribution Off Western Iberian Waters Estimated Through Aerial Surveys, Hélder Araújo, Pedro Correia-Rodrigues, Jorge Bastos-Santos, Marisa Ferreira, Andreia T. Pereira, Jose Martinez-Cedeira, José Vingada, Catarina Eira

Marine Ornithology

Western Iberian waters are important migratory flyways, stopover sites, and wintering areas for several of the world’s seabird species. To describe seabird species composition, distribution, and abundance in these waters, we performed six aerial surveys in September and/ or October of each year, 2010–2015, covering 74 840 km2. Using line-transect methodology, 27 396 seabird sightings from 17 taxonomic groups were recorded along 10496.3 nautical miles (19 433 km). Using the program “Distance,” annual and overall abundance estimates were obtained for nine taxonomic groups: Balearic Shearwater Puffinus mauretanicus, Great Shearwater Ardenna gravis, Cory’s Shearwater Calonectris borealis, shearwaters, Northern Gannet Morus bassanus, …

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Albatross And Petrel Interactions With An Artisanal Squid Fishery In Southern Peru During El Niño, 2015-2017, Cristian Moreno, Javier Quiñones Jul 2025

Albatross And Petrel Interactions With An Artisanal Squid Fishery In Southern Peru During El Niño, 2015-2017, Cristian Moreno, Javier Quiñones

Marine Ornithology

We report on the occurrence of albatrosses (Diomedeidae) and petrels (Procellariidae) associated with an artisanal small-scale fishery (SSF) for Humboldt Squid Dosidicus gigas in waters of southern Peru during El Niño 2015–2016 and coastal El Niño 2017. We deployed as observers on a number of fishing trips to assess seabird interactions. White-chinned Petrels Procellaria aequinoctialis and Waved Albatross Phoebastria irroata were the most abundant species observed, followed by Salvin’s Thalassarche salvini and Chatham T. eremita albatross, and Cape Petrels Daption capense. The majority of procellariid species (> 60% of total birds) visited while vessels were positioned over the continental slope. …

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Diagnosis Of Hypothermia In Seabirds From Coastal California, Nancy L. Anderson Jul 2025

Diagnosis Of Hypothermia In Seabirds From Coastal California, Nancy L. Anderson

Marine Ornithology

This study established cloacal temperature (TCl) cut-off values to diagnose hypothermia in near shore seabirds rescued along the coast of California. All birds died when TCl was < 38.2 °C. When Aechmophorus grebes were excluded, 100% died when TCl was < 38.4 °C. Mortality increased 2–3× when TCl was lower than receiver operating curve-determined criteria for diagnosing hypothermia based on attitude: < 38.8 °C for mixed species, < 39.1 °C for Common Murres Uria aalge, and < 38.2 °C for Aechmophorus grebes. Reductions in TCl as small as 1.0 °C had significant physiologic effects.

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Using Remote Video Technology To Study Environmental Factors Influencing Productivity Of Black-Legged Kittiwakes Rissa Tridactyla, Sarah A. Tanedo, Tuula E. Hollmén, John M. Maniscalco, Sadie E.G. Ulman Jul 2025

Using Remote Video Technology To Study Environmental Factors Influencing Productivity Of Black-Legged Kittiwakes Rissa Tridactyla, Sarah A. Tanedo, Tuula E. Hollmén, John M. Maniscalco, Sadie E.G. Ulman

Marine Ornithology

Monitoring seabirds and their responses to ecosystem change provides essential information for understanding the reasons behind any changes in productivity or populations. However, many species nest in remote locations, which poses logistical challenges for long-term studies. Remote cameras offer an opportunity to confront this issue. The Black-legged Kittiwake Rissa tridactyla (kittiwake) has been used as an indicator of changes in its environment and is a prime candidate for monitoring via remote cameras. To investigate the potential for camera application, we used a remote camera system to collect six years (2010–2015) of reproductive data from a sub-colony of kittiwakes in Resurrection …

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A Test Of Mechanisms Of Population Differentiation In Gannets (Morus Spp.) Using Comparative Phylogeography And Morphometrics, Victoria L. Friesen, Rebecca Brunt, James A. Morris-Pocock, Drew Sauve, Allan J. Baker, Timothy P. Birt, William S. Davidson, Kyle H. Elliott, William A. Montevecchi Jul 2025

A Test Of Mechanisms Of Population Differentiation In Gannets (Morus Spp.) Using Comparative Phylogeography And Morphometrics, Victoria L. Friesen, Rebecca Brunt, James A. Morris-Pocock, Drew Sauve, Allan J. Baker, Timothy P. Birt, William S. Davidson, Kyle H. Elliott, William A. Montevecchi

Marine Ornithology

The relative importance of gene flow, genetic drift, and natural selection in driving genetic divergence of local populations, as well as the factors that disrupt gene flow in natural populations, are uncertain. Comparative analyses enable us to test explicit hypotheses regarding the roles of these factors. Gannets (Morus spp.) include three morphologically and ecologically similar seabird species: the Cape Gannet M. capensis, which breeds in southern Africa; the Australasian Gannet M. serrator, which breeds in southeastern Australia and New Zealand; and the Northern Gannet M. bassanus, which breeds in the North Atlantic. We assessed the extent of differentiation in mitochondrial …

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Hatching Success Of Common Murres Uria Aalge Is Linked To The Number Of Neighbours And Resource Availability, Amy L. Irvine, Julia E. Gulka, Gail K. Davoren Jul 2025

Hatching Success Of Common Murres Uria Aalge Is Linked To The Number Of Neighbours And Resource Availability, Amy L. Irvine, Julia E. Gulka, Gail K. Davoren

Marine Ornithology

When breeding within densely populated colonies, seabirds benefit from increased offspring protection from predators, but intraspecific competition for resources may outweigh these benefits. We tested whether the number of breeding-site neighbours and days of predator presence influenced the breeding performance of Common Murres Uria aalge at two different-sized colonies off the northeastern Newfoundland coast: Cabot Island (10000 breeding pairs; < 10 km offshore) and Funk Island (500000 breeding pairs; ~60 km offshore). Gulls, the main predators of murre eggs/chicks, inhabit both islands in similar numbers. During July–August 2018, camera traps placed at topographically similar plots on each colony recorded breeding performance metrics (i.e., hatching, fledging, reproductive success), number of breeding-site neighbours, and daily presence of gulls. Hatching success was lower at Funk Island (64.7%) than Cabot Island (96.2%), but nearly all hatched chicks fledged at both colonies. Lower hatching success at Funk Island was due to higher egg abandonment and predation. It was also associated with fewer breeding-site neighbours, including non-brooding mates and non-breeders, along with higher gull presence (96.6% of all gull sightings at both colonies). Fewer neighbours at Funk Island may have resulted from mates and non-breeding murres spending more time at sea due to longer distances to predictable foraging sites and higher conspecific densities relative to Cabot Island. In turn, with fewer breeding-site neighbours at Funk Island, parents appeared less able to defend against or deter gull predation. Although Funk Island has special conservation status, protection of Cabot Island may also be important for the long-term conservation of murres in Newfoundland.

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Status And Monitoring Methods Of A Red-Tailed Tropicbird Colony On O'Ahu, Hawai'i, Eric A. Vanderwerf Jul 2025

Status And Monitoring Methods Of A Red-Tailed Tropicbird Colony On O'Ahu, Hawai'i, Eric A. Vanderwerf

Marine Ornithology

The Red-tailed Tropicbird Phaethon rubricauda is a widespread seabird that nests in the tropical Pacific and Indian oceans. Most the global population nests in the predator-free Northwestern Hawaiian Islands. In the southeastern Hawaiian Islands, non-native predators restrict the species to nesting on coastal cliffs and small islets. I monitored 734 Red-tailed Tropicbird nests near Ha¯lona Point on O‘ahu during 2005–2020, controlled non-native predators to protect nests (beginning in 2006), and developed tools to facilitate monitoring of the species in other areas. The colony increased in size in response to predator control, from 18 eggs laid in 2006 to 94 eggs …

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Morphometric Sex Determination Of Breeding Adult Royal Thalasseus Maximus And Sandwich Terns T. Sandvicensis In Louisiana, Megan Nepshinsky, Sabrina S. Taylor, Jeff S. Liechty, Ashlee K. Minor, Eva D. Windhoffer, Aaron R. Pierce Jul 2025

Morphometric Sex Determination Of Breeding Adult Royal Thalasseus Maximus And Sandwich Terns T. Sandvicensis In Louisiana, Megan Nepshinsky, Sabrina S. Taylor, Jeff S. Liechty, Ashlee K. Minor, Eva D. Windhoffer, Aaron R. Pierce

Marine Ornithology

Many seabirds have sex-specific traits, including survival, philopatry, behavior, and diet, information that is essential for effective conservation strategies. The difficulty of sexing monomorphic seabirds, however, has resulted in a lack of information on these important traits and an incomplete understanding of the ecology of many species. We used a polymerase chain reaction (PCR)-based sexing approach to determine if Royal Thalasseus maximus and Sandwich terns T. sandvicensis in Louisiana, USA can be accurately sexed using morphometrics. DNA samples and morphological measurements were obtained from Royal Terns (n = 106) and Sandwich Terns (n = 112) to accurately identify sex and …

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