Breeding of Cory's shearwater Calonectris borealis on Selvagem Grande and beneficial effects of removal of invasive mammals

Abstract The largest colony of Cory's shearwater Calonectris borealis nests on the island of Selvagem Grande in the north-eastern Atlantic. In 2002, a programme of eradication was conducted to remove two alien invasive mammals, the house mouse Mus musculus and European rabbit Oryctolagus cuniculus. Preliminary studies recorded beneficial effects of the eradications for a variety of plant and animal species, including Cory's shearwater. We recorded fledging rates of shearwaters for 1982–2001, prior to the eradication, and for 2002–2020, after the eradication, from two quadrats, each containing 134–329 nest sites. Although there was annual fluctuation in fledging rates in the quadrats, the mean rate of 40.74 ±SD 3.92 fledglings per 100 nest sites for the two quadrats combined prior to the eradication of mammals increased significantly, to 52.88 ± SD 5.03 per 100 nest sites, after the eradications. Because the two mammals were removed synchronously it is difficult to know which factors depressed fledging of Cory's shearwaters on Selvagem Grande. However, the predatory behaviour of house mice on other oceanic islands, and the fact that increased fledging was seen soon after the eradications occurred, suggest predation by house mice on shearwater hatchlings was the main cause of losses.

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Mouse eradication is required to prevent local extinction of an endangered seabird on an oceanic island

10.1101/2020.11.16.385997 ◽

2020 ◽

Author(s):

Christopher W. Jones ◽

Michelle M. Risi ◽

Alexis M. Osborne ◽

Peter G. Ryan ◽

Steffen Oppel

Keyword(s):

Breeding Success ◽

Extinction Risk ◽

Oceanic Islands ◽

Adult Survival ◽

House Mice ◽

Breeding Populations ◽

Gough Island ◽

Invasive Mammals ◽

Population Trajectory ◽

The Impact

AbstractPetrels (Procellariidae) are a highly diverse family of seabirds, many of which are globally threatened due to the impact of invasive species on breeding populations. While predation by invasive cats and rats has led to the extinction of petrel populations, the impact of invasive house mice Mus musculus is slower and less well documented. However, mice impact small burrow-nesting species such as MacGillivray’s prion Pachyptila macgillivrayi, a species classified as endangered because it has been extirpated on islands in the Indian Ocean by introduced rodents. We use historic abundance data and demographic monitoring data from 2014 to 2020 to predict the population trajectory of MacGillivray’s prion on Gough Island with and without a mouse eradication using a stochastic integrated population model. Given very low annual breeding success (0.01 fledglings per breeding pair in ‘poor’ years (83%) or 0.38 in ‘good’ years (17%), n = 320 nests over 6 years) mainly due to mouse predation, our model predicted that the population collapsed from ~3.5 million pairs in 1956 to an estimated 175,000 pairs in 2020 despite reasonably high adult survival probability (ϕ = 0.901). Based on these parameters, the population is predicted to decline at a rate of 9% per year over the next 36 years without a mouse eradication, with a 31% probability that by 2057 the MacGillivray’ prion population would become extremely vulnerable to extinction. Our models predict population stability (λ = 1.01) and a lower extinction risk (<10%) if mouse eradication on Gough Island restores annual breeding success to 0.519, which is in line with that of closely-related species on predator-free islands. This study demonstrates the devastating impacts that introduced house mice can have on small burrowing petrels and highlights the urgency to eradicate invasive mammals from oceanic islands.

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Observations of mice predation on dark-mantled sooty albatross and Atlantic yellow-nosed albatross chicks at Gough Island

Antarctic Science ◽

10.1017/s0954102013000126 ◽

2013 ◽

Vol 25 (6) ◽

pp. 763-766 ◽

Cited By ~ 12

Author(s):

R.J. Cuthbert ◽

H. Louw ◽

G. Parker ◽

K. Rexer-Huber ◽

P. Visser

Keyword(s):

Invasive Species ◽

Mus Musculus ◽

House Mice ◽

Marion Island ◽

Predatory Behaviour ◽

Gough Island ◽

Conservation Actions ◽

Breeding Seasons ◽

The Impact ◽

Ongoing Monitoring

AbstractIntroduced house miceMus musculusL. have been discovered to be major predators of chicks of the Tristan albatrossDiomedea dabbenenaL. and Atlantic petrelPterodroma incertaSchlegel and to also predate great shearwaterPuffinus gravisO'Reilly chicks at Gough Island, and similar predatory behaviour has been reported for house mice on Marion Island. Observations on Gough Island over three breeding seasons of nesting Atlantic yellow-nosed albatrossesThalassarche chlororhynchosGmelin and dark-mantled sooty albatrossPhoebetria fuscaHilsenberg indicate that house mice are also preying on these two species: the first records of mice preying upon summer-breeding albatross species on Gough Island. Predation on these two albatross species appears to be relatively rare (∼2% for the Atlantic yellow-nosed albatrosses) and ongoing monitoring is required to ascertain if the impact of mice is increasing. Conservation actions to eradicate mice from Gough Island will be of benefit to these species and other species that are being impacted by this invasive species.

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Methods and ethical considerations of pitfall trapping for the western pygmy possum (Cercartetus concinnus Gould) (Marsupialia:Burramyidae), with observations on capture patterns and nest sites

Wildlife Research ◽

10.1071/wr06090 ◽

2007 ◽

Vol 34 (4) ◽

pp. 296 ◽

Cited By ~ 17

Author(s):

Angela J. L. Pestell ◽

Sophie Petit

Keyword(s):

Capture Rate ◽

South Australia ◽

Trap Depth ◽

Pitfall Trap ◽

House Mice ◽

Pitfall Trapping ◽

Ethical Considerations ◽

Ethical Implications ◽

Nest Sites ◽

Autumn And Winter

In order to enhance future trapping of the western pygmy possum (Cercartetus concinnus) and minimise the capture of non-target species in the context of animal ethics, we examined the effectiveness of several pitfall-trap capture methods and described capture patterns at Innes National Park, South Australia. For 2606 trap-nights, 78 (2.99 per 100 trap-nights) captures were pygmy possums (70 individuals). They represented 69% of the 113 vertebrates captured, followed by house mice (Mus domesticus) (22%). Nocturnal captures of pygmy possums varied with season (5.21 per 100 trap-nights in spring and summer, and 1.02 in autumn and winter). Males were more commonly captured than females. Half of the pygmy possums used the artificial shelters provided in the traps. We alternated 39-cm-deep and 31-cm-deep pitfall traps along trap lines, with and without drift netting. Pitfall depth did not significantly affect the capture rate of pygmy possums, but house mice were captured significantly more often in deep pitfalls. Use of a drift net did not affect the capture of pygmy possums, but increased mouse captures. These results have significant ethical implications because the use of ‘shallow’ traps and the elimination of the drift net minimised the capture of non-target mice. We recommend reporting trapping details precisely, because a difference of only 8 cm in trap depth can have a significant impact on species selected for capture. Our study also showed that pygmy possums are able to use a range of structures for daily shelter and are not dependent on hollows.

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Old habits die hard: Mouse handling by a pitviper species on a rodent-free island

Amphibia-Reptilia ◽

10.1163/156853809788795092 ◽

2009 ◽

Vol 30 (3) ◽

pp. 435-438 ◽

Cited By ~ 3

Author(s):

Ivan Sazima ◽

Otavio Marques

Keyword(s):

Migratory Birds ◽

Prey Type ◽

Immediate Release ◽

Southeastern Brazil ◽

House Mice ◽

Predatory Behaviour ◽

Phylogenetic Conservatism ◽

Specialized Diet

AbstractThe golden lancehead (Bothrops insularis) is endemic to Queimada Grande Island off the coast of southeastern Brazil. This pitviper feeds mainly on migratory birds, whereas mainland pitvipers in the genus Bothrops usually feed on rodents. Rodents are regarded as a dangerous prey type, and the habitual handling of rodents by pitvipers include its immediate release after the initial bite. However, bird prey is usually held within jaws after the initial bite. Presently there are no rodents in Queimada Grande Island, which is thought to have isolated from the mainland 11 000 yr ago. We staged encounters between B. insularis and house mice in the field to evaluate how the snake will behave when introduced to a supposedly unknown prey type. Mice were readily accepted as prey and the predatory behaviour of B. insularis was similar to that displayed by mainland pitvipers (strike-release). Although B. insularis has several morphological and ecological particularities that likely developed during its isolation on an island (some of these related to a specialized diet and/or arboreal habits), the handling behaviour of potentially dangerous prey such as rodents was retained – an indication of phylogenetic conservatism.

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Feral pigeons as a nest competitor for a small seabird

10.21203/rs.3.rs-550854/v1 ◽

2021 ◽

Author(s):

Beneharo Rodríguez ◽

Airam Rodríguez ◽

Felipe Siverio ◽

Juan Manuel Martínez ◽

Enrique Sacramento ◽

...

Keyword(s):

Breeding Success ◽

Columba Livia ◽

Pathogen Transmission ◽

Nest Density ◽

Nest Location ◽

Nest Sites ◽

Breeding Failure ◽

Nesting Sites ◽

Calonectris Borealis

Abstract Due to their life-history traits, the petrels are particularly sensitive to predation by introduced species. Therefore, many populations have constricted their original breeding distribution range, currently only occupying predator-free sites. In this scenario, interspecific competition for nesting sites can be detrimental for the petrel’ conservation. Here, we evaluate how the presence of introduced mammals (cats Felis catus and rats Rattus spp.) and potential competitors for nest sites (Cory’s shearwaters Calonectris borealis and feral rock pigeons Columba livia) shape the distribution, breeding density, and breeding performance of the Bulwer’s petrel Bulweria bulwerii on Tenerife, the largest and most densely populated of the Canary Islands. We estimated nest density, assessed the role of nest location and nest characteristics on breeding success, and determined causes of breeding failure by exotic predators and competitors. Nest density was higher in predator-free colonies on marine rocks. Cat presence was the best predictor for nest density, while presence or abundance of competitors had no correlation to nest density. Breeding success varied between years and colonies, but was not related to nest characteristics. Of the unequivocally determined causes of breeding failure, pigeon competition for nests was the most frequent (7.3%), followed by rat predation (6.3%). We also compared petrel and pigeon nest cavities and found a considerable overlap in nesting niche. Our study provides insight on an overlooked impact of the invasive rock pigeon: nest competition with small seabirds. We encourage more research on the effects of pigeons on nest density, disease and pathogen transmission, and vegetation changes within petrel colonies.

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Can predation by invasive mice drive seabird extinctions?

Biology Letters ◽

10.1098/rsbl.2007.0120 ◽

2007 ◽

Vol 3 (3) ◽

pp. 241-244 ◽

Cited By ~ 126

Author(s):

Ross M Wanless ◽

Andrea Angel ◽

Richard J Cuthbert ◽

Geoff M Hilton ◽

Peter G Ryan

Keyword(s):

Atlantic Ocean ◽

House Mouse ◽

Mus Musculus ◽

Breeding Success ◽

Population Models ◽

South Atlantic Ocean ◽

House Mice ◽

Seabird Species ◽

Gough Island ◽

Invasive Mammals

The house mouse, Mus musculus , is one of the most widespread and well-studied invasive mammals on islands. It was thought to pose little risk to seabirds, but video evidence from Gough Island, South Atlantic Ocean shows house mice killing chicks of two IUCN-listed seabird species. Mouse-induced mortality in 2004 was a significant cause of extremely poor breeding success for Tristan albatrosses, Diomedea dabbenena (0.27 fledglings/pair), and Atlantic petrels, Pterodroma incerta (0.33). Population models show that these levels of predation are sufficient to cause population decreases. Unlike many other islands, mice are the only introduced mammals on Gough Island. However, restoration programmes to eradicate rats and other introduced mammals from islands are increasing the number of islands where mice are the sole alien mammals. If these mouse populations are released from the ecological effects of predators and competitors, they too may become predatory on seabird chicks.

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Do ship rats display predatory behaviour towards house mice?

Animal Behaviour ◽

10.1016/j.anbehav.2013.05.013 ◽

2013 ◽

Vol 86 (2) ◽

pp. 257-268 ◽

Cited By ~ 17

Author(s):

L.J. Bridgman ◽

J. Innes ◽

C. Gillies ◽

N.B. Fitzgerald ◽

S. Miller ◽

...

Keyword(s):

House Mice ◽

Predatory Behaviour

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Low spatial overlap between foraging shearwaters during the breeding season and industrial fisheries off the west coast of Portugal

Marine Ecology Progress Series ◽

10.3354/meps13549 ◽

2021 ◽

Vol 657 ◽

pp. 209-221

Author(s):

JM Pereira ◽

JA Ramos ◽

AM Marques ◽

FR Ceia ◽

L Krüger ◽

...

Keyword(s):

Breeding Season ◽

Prey Availability ◽

Resource Depletion ◽

Fishing Effort ◽

Population Variation ◽

Breeding Period ◽

Spatial Overlap ◽

Cory’S Shearwater ◽

Fishing Vessels ◽

Calonectris Borealis

Fisheries have impacted seabird populations worldwide, either via bycatch mortality or resource depletion. Understanding the overlap between seabird distributions and fisheries is an important element for bycatch risk assessment, though the drivers of variation in seabird-fishery overlap are not well understood for some seabird populations. Here, we quantified the spatial overlap between foraging Cory’s shearwaters Calonectris borealis during the breeding season and commercial fisheries operating within the Portuguese Exclusive Economic Zone. In addition, we evaluated whether overlap varied as a function of an individual’s boldness, sex or breeding stage. For this, we GPS tracked 361 foraging trips by 72 Cory's shearwaters nesting at Berlenga Island, Portugal, over 5 consecutive breeding seasons (2012-2016). Simultaneously, we used fishing effort data from Global Fishing Watch detailing the distribution of industrial fisheries within the temporal and spatial range of Cory's shearwater tracks. Although fishing vessels were present during 88.1% of foraging trips, Cory's shearwaters spent only on average 13.3% of the time foraging in the same areas as fisheries. Such low spatial overlap is likely driven by high prey availability near the colony and suggests low direct competition for resources. We also found variation in overlap with fisheries across the breeding period, with Cory's shearwaters spending approximately 11% more time foraging in the same areas as fixed gear and purse seine vessels during pre-laying than during chick-rearing. Surprisingly, no sex or boldness-related differences were found in the overlap with any fishing gear. Our findings have implications for understanding within population variation in the overlap between fisheries and seabirds and, in turn, bycatch risk.

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Low burrow occupancy and breeding success of burrowing petrels at Gough Island: a consequence of mouse predation

Bird Conservation International ◽

10.1017/s0959270912000494 ◽

2013 ◽

Vol 23 (2) ◽

pp. 113-124 ◽

Cited By ~ 22

Author(s):

RICHARD J. CUTHBERT ◽

HENK LOUW ◽

JEROEN LURLING ◽

GRAHAM PARKER ◽

KALINKA REXER-HUBER ◽

...

Keyword(s):

Mus Musculus ◽

Breeding Success ◽

House Mice ◽

Population Declines ◽

Predatory Behaviour ◽

Breeding Parameters ◽

Gough Island ◽

The Impact ◽

Detrimental Impact ◽

Winter Breeding

SummaryThe predatory behaviour of introduced house mice Mus musculus at Gough Island is known to impact on albatross and petrels, resulting in the Tristan Albatross Diomedea dabbenena and Atlantic Petrel Pterodroma incerta being listed as “Critically Endangered” and “Endangered”, respectively. Although predation has been documented for two burrowing petrels and one albatross species, the impact of house mice on other burrowing petrels on Gough Island is unknown. We report burrow occupancy and breeding success of Atlantic Petrels, Soft-plumaged Petrels Pterodroma mollis, Broad-billed Prions Pachyptila vittata, Grey Petrels Procellaria cinerea and Great Shearwaters Puffinus gravis. With the exception of the Great Shearwater, breeding parameters of burrowing petrels at Gough Island were very poor, with low burrow occupancy (range 4–42%) and low breeding success (0–44%) for four species, and high rates of chick mortality in Atlantic Petrel burrows. Breeding success decreased with mass, suggesting that smaller species are hardest hit, and winter-breeding species had lower breeding success than summer breeders. The results indicate that introduced house mice are having a detrimental impact on a wider range of species than previously recorded and are likely to be causing population declines among most burrowing petrels on Gough Island. The very low values of burrow occupancy recorded for Soft-plumaged Petrels and Broad-billed Prions and greatly reduced abundance of burrowing petrels in comparison to earlier decades indicate that Gough Island’s formerly abundant petrel populations are greatly threatened by the impact of predatory house mice which can only be halted by the eradication of this species from the island.

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