Long-term inter- and intraspecific dietary variation in sibling seabird species

SummaryGlobal seabird populations are in decline, with nearly half of all seabird species currently in an extinction crisis. Understanding long-term seabird population trends is an essential first step to inform conservation actions. In this study, we assembled historical breeding records of seabirds throughout the Japanese archipelago and quantified the long-term population trends of 10 major breeding seabird species using a hierarchical Bayesian state-space model. The model revealed that six species had increasing or no detectable trends (Short-tailed Albatross Phoebastria albatrus, Leach’s Storm Petrel Oceanodroma leucorhoa, Pelagic Cormorant Phalacrocorax pelagicus, Japanese Cormorant Phalacrocorax capillatus, Spectacled Guillemot Cepphus carbo, and Rhinoceros Auklet Cerorhinca monocerata). However, decreasing trends were found not only in nationally threatened species (Common Murre Uria aalge, and Tufted Puffin Fratercula cirrhata) but also common species that are often described as abundant (Black-tailed Gull Larus crassirostris and Slaty-backed Gull Larus schistisagus). These declining species have declined to 3–35% of baseline levels over the past 30 years. This study provides the first evidence of long-term declines in common and widespread seabirds in Japan.

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Geographic variation in the diet of the powerful owl (Ninox strenua) at a local scale

Australian Journal of Zoology ◽

10.1071/zo13048 ◽

2013 ◽

Vol 61 (5) ◽

pp. 372 ◽

Cited By ~ 3

Author(s):

Rohan J. Bilney

Keyword(s):

Coastal Forests ◽

Forest Sites ◽

Sugar Glider ◽

Pseudocheirus Peregrinus ◽

The Common ◽

Dietary Variation ◽

Conservation Concern ◽

Petaurus Breviceps ◽

Ringtail Possum

This study reports the diet of the powerful owl (Ninox strenua) in East Gippsland, from a dataset of 2009 vertebrate prey items collected from 53 sites. Mammals dominated the diet at all sites, but birds were also consumed regularly. The greater glider (Petauroides volans) was the dominant dietary item across the region in terms of both frequency of consumption and biomass contribution. There was geographical dietary variation between coastal and foothill forest sites, with the sugar glider (Petaurus breviceps) and birds consumed more frequently in foothill forests, whereas the common ringtail possum (Pseudocheirus peregrinus) was frequently consumed only in coastal forests. Typically, a higher percentage of powerful owl diet comprised birds closer to cleared land. The dietary reliance upon hollow-dependent mammals in foothill forests (averaging >70%) is of conservation concern, especially when non-hollow-dependent prey are rare. Forest management activities, especially logging, that reduce densities of hollow-bearing trees in the landscape are therefore likely to decrease the long-term carrying capacity of the landscape for the powerful owl.

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Seabirds of the Benguela Ecosystem: Utilisation, Long-Term Changes and Challenges

10.5772/intechopen.96326 ◽

2021 ◽

Author(s):

Azwianewi B. Makhado ◽

Rodney Braby ◽

Bruce M. Dyer ◽

Jessica Kemper ◽

Alistair M. McInnes ◽

...

Keyword(s):

Habitat Degradation ◽

Seabird Species ◽

Endemic Birds ◽

Benguela Current ◽

Spheniscus Demersus ◽

By Catch ◽

Ecosystem Benefits ◽

Near Threatened ◽

Important Bird Area

The Benguela Current is used by c. 82 seabird species, of which seven are endemic to it. Eggs and guano of formerly abundant seabirds were heavily harvested in the 19th and 20th centuries but decreases in seabird populations led to cessation of these industries at islands. Guano is still scraped from platforms. Seabird ecotourism has grown. There were large recent decreases in numbers of African Penguins Spheniscus demersus, Cape Gannets Morus capensis and Cape Phalacrocorax capensis and Bank P. neglectus Cormorants and redistributions of these other species away from the centre of the Benguela ecosystem towards its northern or eastern boundaries. In 2020, seabirds endemic to the Benguela ecosystem and albatrosses and petrels migrating into it had high proportions of globally Near Threatened or Threatened species. The primary threat to four Endangered endemic birds was scarcity of forage resources. A Vulnerable endemic damara tern was susceptible to habitat degradation and disturbance. The principal threat to visiting albatrosses and petrels was by-catch mortality. Identification and effective protection of Important Bird Area breeding and marine foraging and aggregation sites, and a suite of complementary measures, are needed to conserve the seabirds and ensure continuation of their economic and ecosystem benefits into the future.

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Captive husbandry and veterinary care of seabirds during the MV Rena oil spill response

Wildlife Research ◽

10.1071/wr19006 ◽

2019 ◽

Vol 46 (7) ◽

pp. 610 ◽

Cited By ~ 5

Author(s):

B. D. Gartrell ◽

P. F. Battley ◽

C. Clumpner ◽

W. Dwyer ◽

S. Hunter ◽

...

Keyword(s):

Body Condition ◽

The Body ◽

Fuel Oil ◽

Heavy Fuel Oil ◽

Seabird Species ◽

Rehabilitation Protocols ◽

Common Causes ◽

Oil Spill Response ◽

Species Specific

Abstract ContextSeabirds were the most common taxa captured alive as part of the oiled wildlife response to the grounding of the container vessel MV Rena in the Bay of Plenty, New Zealand. AimsTo describe the management of seabirds during the spill response, to outline the common problems encountered and to make recommendations for future responses. MethodsSeabirds were collected from 7 October 2011 to 14 January 2012. They were stabilised and underwent pretreatment, washing and rinsing procedures to remove oil, followed by swimming physiotherapy to restore waterproofing and long-term housing in outdoor aviaries. The birds were released in batches close to the original sites of capture once the wild habitat was cleaned. Key results428 live seabirds were admitted. There were two temporal peaks in admissions associated with the ship grounding and when the ship broke up. The majority of live birds were little penguins (Eudyptula minor; 394/428, 92%). Most seabirds admitted (393/428, 91.8%) were contaminated with heavy fuel oil, with the remainder (35/428, 8.2%) found unoiled but starving and/or exhausted or with injuries. Little penguins had lower mortality during rehabilitation (28/394, 7.1%) than other seabird species combined (27/34, 79.4%). Seabirds in poorer body condition on arrival had higher mortality, and unoiled birds were also more likely to die than oiled birds. In oiled little penguins, the degree of oiling on the plumage ranged from 1 to 100%, but mortality was not significantly associated with the degree of oiling (P=0.887). Pododermatitis affected 66% of little penguins. The most common causes of death (n=45) included weakness, anaemia and hypothermia in oiled seabirds (16/45, 35.6%), and starvation and weakness in unoiled seabirds (14/45, 31.1%). ConclusionsTotal survival to release was 87.1%, primarily influenced by the species involved and the body condition of the birds on arrival. Unoiled seabirds had higher mortality rates than oiled seabirds. ImplicationsOiled wildlife can be rehabilitated with good success, even when heavily oiled, or to a lesser extent, when found in poor body condition. More work is needed to refine species-specific rehabilitation protocols for seabirds, especially for those being admitted in emaciated body condition.

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Change in the North Sea ecosystem from the 1970s to the 2010s: great skua diets reflect changing forage fish, seabirds, and fisheries

ICES Journal of Marine Science ◽

10.1093/icesjms/fsy165 ◽

2018 ◽

Vol 76 (4) ◽

pp. 925-937 ◽

Cited By ~ 2

Author(s):

Gabriella E Church ◽

Robert W Furness ◽

Glen Tyler ◽

Lucy Gilbert ◽

Stephen C Votier

Keyword(s):

North Sea ◽

Anthropogenic Impacts ◽

Marine Ecosystem ◽

Commercial Fishing ◽

Seabird Species ◽

Rissa Tridactyla ◽

Fulmarus Glacialis ◽

The North ◽

The North Sea

Abstract Understanding anthropogenic impacts are crucial to maintain marine ecosystem health. The North Sea has changed in recent decades, largely due to commercial fishing and climate change. Seabirds can act as useful indicators of these changes. By analyzing n = 20 013 pellets and n = 24 993 otoliths regurgitated by great skuas Stercorarius skua in northern Scotland over five decades from the 1970s to the 2010s (in 36 years 1973–2017), we reveal how the diet of this top predator has changed alongside the changing North Sea ecosystem. Sandeels Ammodytes spp. were the most common dietary item during the 1970s, but became virtually absent from the 1980s onward. Discarded whitefish dominated skua diets from the 1980s to the present day, despite long-term declines in North Sea discard production. However, the discarded fish eaten by great skuas has become smaller and the species composition changed. Skua pellets only rarely contained avian prey in the 1970s but this increased during the 1980s, and fluctuated between 10% and 20% from the 1990s to 2010s. There have also been changes in the avian prey in the diet—black-legged kittiwakes Rissa tridactyla generally being replaced by auks Alcid spp. and northern fulmars Fulmarus glacialis. The Shetland marine ecosystem has experienced steep declines in sandeel stocks and in seabirds that feed on them. Great skuas have been able to prey switch to respond to this change, supported by abundant discards, enabling them to maintain a favourable population status while other seabird species have declined.

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LONG-TERM CONTRASTED RESPONSES TO CLIMATE OF TWO ANTARCTIC SEABIRD SPECIES

Ecology ◽

10.1890/05-0514 ◽

2005 ◽

Vol 86 (11) ◽

pp. 2889-2903 ◽

Cited By ~ 126

Author(s):

Stephanie Jenouvrier ◽

Christophe Barbraud ◽

Henri Weimerskirch

Keyword(s):

Seabird Species

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Cross-species screening of microsatellite markers for individual identification of snow petrel Pagodroma nivea and Wilson's storm petrel Oceanites oceanicus in Antarctica

PeerJ ◽

10.7717/peerj.5243 ◽

2018 ◽

Vol 6 ◽

pp. e5243 ◽

Cited By ~ 1

Author(s):

Anant Pande ◽

Nidhi Rawat ◽

Kuppusamy Sivakumar ◽

Sambandam Sathyakumar ◽

Vinod B. Mathur ◽

...

Keyword(s):

Microsatellite Markers ◽

Marine Ecosystem ◽

Genetic Research ◽

Species Group ◽

Individual Identification ◽

Seabird Species ◽

Snow Petrel ◽

Storm Petrel ◽

Oceanites Oceanicus

Seabirds are important indicators of marine ecosystem health. Species within the order Procellariiformes are the most abundant seabird species group distributed from warm tropical to cold temperate regions including Antarctica. There is a paucity of information on basic biology of the pelagic seabird species nesting on the Antarctic continents, and long-term studies are required to gather data on their population demography, genetics and other ecological parameters. Under the ‘Biology and Environmental Sciences’ component of the Indian Antarctic programme, long-term monitoring of Antarctic biodiversity is being conducted. In this paper, we describe results of cross-species screening of a panel of 12 and 10 microsatellite markers in two relatively little studied seabird species in Antarctica, the snow petrel Pagodroma nivea and the Wilson's storm petrel Oceanites oceanicus, respectively. These loci showed high amplification success and moderate levels of polymorphism in snow petrel (mean no. of alleles 7.08 ± 3.01 and mean observed heterozygosity 0.35 ± 0.23), but low polymorphism in Wilson's storm petrel (mean no. of alleles 3.9 ± 1.3 and mean observed heterozygosity 0.28 ± 0.18). The results demonstrate that these panels can unambiguously identify individuals of both species (cumulative PIDsibs for snow petrel is 3.7 × 10−03 and Wilson's storm petrel is 1.9 × 10−02) from field-collected samples. This work forms a baseline for undertaking long-term genetic research of these Antarctic seabird species and provides critical insights into their population genetics.

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Response of Native Species 10 Years After Rat Eradication on Anacapa Island, California

Journal of Fish and Wildlife Management ◽

10.3996/082015-jfwm-073 ◽

2016 ◽

Vol 7 (1) ◽

pp. 72-85 ◽

Cited By ~ 6

Author(s):

Kelly M. Newton ◽

Matthew McKown ◽

Coral Wolf ◽

Holly Gellerman ◽

Tim Coonan ◽

...

Keyword(s):

Native Species ◽

Deer Mouse ◽

Rattus Rattus ◽

Negative Effects ◽

International Union ◽

Seabird Species ◽

Cassin's Auklet ◽

Conservation Actions ◽

Ptychoramphus Aleuticus

Abstract Measuring the response of native species to conservation actions is necessary to inform continued improvement of conservation practices. This is particularly true for eradications of invasive vertebrates from islands where up-front costs are high, actions may be controversial, and there is potential for negative impacts to native (“nontarget”) species. We summarize available data on the response of native species on Anacapa Island, California, 10 y after the eradication of invasive black rats Rattus rattus. Native marine taxa hypothesized to respond positively to rat eradication increased in abundance (Scripps's murrelet Synthliboramphus scrippsi; International Union for Conservation of Nature Vulnerable, and intertidal invertebrates). Two seabird species likely extirpated by rats—ashy storm-petrel Oceanodroma homochroa (International Union for Conservation of Nature Endangered) and Cassin's auklet Ptychoramphus aleuticus—are now confirmed to breed on the island. Long-term negative effects from nontarget impacts are limited. Rufous-crowned sparrows Aimophila ruficeps obscura are still present, although likely in lower abundance. The endemic Anacapa deer mouse Peromyscus maniculatus anacapae population increased with no loss in heterozygosity, but with reduced genetic differentiation on East Anacapa and the loss of some alleles across the islets. Intertidal invertebrate cover increased while algal cover decreased. These findings clarify the pervasive effects of invasive rats on a wide variety of taxa, the short- and long-term impacts of eradication, and the ability of some island fauna to passively recover following a carefully planned rat-eradication project.

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Seabirds in Conditions of Local Chronic Oil Pollution, Davis Sea, Antarctica

Birds ◽

10.3390/birds2030020 ◽

2021 ◽

Vol 2 (3) ◽

pp. 275-284

Author(s):

Sergey Golubev

Keyword(s):

Breeding Season ◽

Oil Spills ◽

Oil Pollution ◽

Bird Species ◽

East Antarctica ◽

Pygoscelis Adeliae ◽

Seabird Species ◽

Eudyptes Chrysolophus ◽

Adélie Penguins

Oil spills are rare in Antarctica. They threaten flying birds and penguins. This is the first report on the interactions of seabirds with oil in the area of the Mirny Station (East Antarctica). The purpose of the study is to determine the total number of seabird species interacting with oil in and around the Mirny Station, to assess the extent of pollution and to identify the most important sites of interactions. Oil pollution is found on the ground, on the continental ice and, on the seawater surface, both directly in the Mirny and beyond. Five species of seabirds were in contact with oil. Oil pollution threats have been identified for breeding and molting Adélie Penguins (Pygoscelis adeliae) and vagrant Macaroni Penguins (Eudyptes chrysolophus). Less affected by oil pollution during the breeding season were tube-nosed bird species and skuas. The most important places of interaction of seabirds with oil are at Cape Mabus, on the islands of Zykov, Tokarev, and Stroiteley. Evidence of long-term oil pollution of the environment is indicative of the chronic nature of the impacts on the coastal ecosystem.

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Standardizing microsatellite panels for individual identification of seabirds’ Snow Petrel Pagodroma nivea and Wilson’s Storm Petrel Oceanites oceanicus in Antarctica

10.1101/221861 ◽

2017 ◽

Author(s):

Anant Pande ◽

Nidhi Rawat ◽

Kuppusamy Sivakumar ◽

Sambandan Sathyakumar ◽

Vinod B. Mathur ◽

...

Keyword(s):

Genetic Research ◽

Individual Identification ◽

Seabird Species ◽

Snow Petrel ◽

Antarctic Continent ◽

The Antarctic ◽

Past Population ◽

Storm Petrel ◽

Oceanites Oceanicus

ABSTRACTSeabirds are known to be important indicators of marine ecosystems health. Procellariiformes are one of the most abundant seabird species distributed from warm tropical to cold temperate regions including Antarctica. With few long-term studies on breeding seabirds at the Antarctic continent, crucial biological parameters such as genetic variation, population genetic structure and past population demography is lacking for most of the commonly occurring species. Under the ‘Biology and Environmental Sciences’ component of the Indian Antarctic programme, long-term monitoring of Antarctic biodiversity is being conducted. In this paper, we describe a panel of 12 and 10 cross-species microsatellite markers for two relatively less studied seabird species in Antarctica, snow petrel Pagodroma nivea and Wilson’s storm petrel Oceanites oceanicus, respectively. These loci showed high amplification success and moderate level of polymorphism in snow petrel (mean no. of alleles 7.08±3.01 and mean observed heterozygosity 0.35±0.23), but low polymorphism in Wilson’s storm petrel (mean no. of alleles 3.9±1.3 and mean observed heterozygosity 0.28±0.18). The results demonstrate that these panels can unambiguously identify individuals of both species from various types of biological materials. This work forms a baseline for undertaking long-term genetic research of Antarctic seabird species and provides critical insights into their population genetics.

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