Volume 50, No. 2

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Owl depredation at a re-establishing colony of White-faced Storm Petrel Pelagodroma marina


1Department of Planning, Industry and Environment, Locked Bag 5022, Parramatta New South Wales 2124, Australia (
2Wiyanga Pty Ltd, 20 Godfrey Street, Penshurst, New South Wales 2222, Australia


CARLILE, N. & LLOYD, C. 2022. Owl depredation at a re-establishing colony of White-faced Storm Petrel Pelagodroma marina. Marine Ornithology 50: 133 - 141

Received 28 October 2021, accepted 13 April 2022

Date Published: 2022/10/15
Date Online: 2022/09/22
Key words: Barn Owl, colony establishment, owl depredation, White-faced Storm-Petrel


We report the depredation by a single Australian Barn Owl Tyto alba delicatula on prospecting White-faced Storm Petrels Pelagodroma marina during the re-establishment phase of a colony on Big Island, off Port Kembla, New South Wales, Australia in 2018. Storm petrels were likely extirpated from this colony 56 years previously when invasive weeds rendered their habitat inaccessible. Restoration of vegetation together with storm petrel call broadcasting, commencing in 2014, resulted in significant increases in prospecting numbers, culminating in breeding (three pairs) in the 2017/18 austral summer season. A significant depredation event (> 59 adults) occurred between August and September 2018, providing a set-back to colony establishment. Previously, Barn Owl depredation on Big Island had been limited to Silver Gulls Chroicocephalus novaehollandiae as prey. However, in the 2018/19 season, the gulls commenced nesting later than usual. The delay appeared to cause the owl to switch target prey. Despite the intense depredation pressure, at least two pairs of storm petrels attempted to breed in the 2018/19 season and 10 birds were trapped and banded at the commencement of the 2019/20 season. Discovery of the mainland roost of the owl was attempted between the two seasons, and its potential death by car strike was investigated. Our findings show that even a single individual predator can have significant impacts on seabird colonies establishing or re-establishing in island environments, especially those under restoration.


BARRETT, G., SILCOCKS, A., BARRY, S., CUNNINGHAM, R. & POULTER, R. 2003. The New Atlas of Australian Birds. Victoria, Australia: Royal Australian Ornithological Union.

BECKER, P. & BRADLEY, J. 2007. The role of intrinsic factors for the recruitment process in long-lived birds. Journal of Ornithology 148: 377-384.

BESTER, A.J., PRIDDEL, D., KLOMP, N.I., CARLILE, N. & O'NEILL, L.E. 2007. Reproductive success of the Providence Petrel Pterodroma solandri on Lord Howe Island, Australia. Marine Ornithology 35: 21-28.

BIRDLIFE INTERNATIONAL 2022. Species factsheet: Pelagodroma marina. Cambridge, UK: Birdlife International. [Accessed at on 21 March 2022.]

BONTEMPO, L., CEPPA, F., ZILLER, L. ET AL. 2014. Comparison of methods for stable isotope ratio (δ13C, δ15N, δ2H, δ18O) measurements of feathers. Methods in Ecology and Evolution 5: 363-371.

BROTHERS, N.P. 1981. Observations of breeding success in White-faced Storm-petrel at a newly established colony. Corella 5: 29-33.

BUXTON, R.T., JONES, C., MOLLER, H. & TOWNS, D.R. 2014. Drivers of seabird population recovery on New Zealand islands after predator eradication. Conservation Biology 28: 334-344.

CARLILE, N. 2019. Seabird islands No. 41/1: Martin Islet, Five Islands Group, New South Wales. Corella 43: 39-41.

CARLILE, N., HARRIS, A. & LLOYD, C. 2020. Seabird islands No. 2/1: Montague Island, New South Wales - Additional Breeding Seabirds. Corella 44: A1-A3.

CARLILE, N., LLOYD, C., MORRIS, R., BATTAM, H. & SMITH, L. 2017. Seabird islands No. 38/1: Big Island, Five Islands Group, New South Wales. Corella 41: 57-62.

CARLILE, N. & PRIDDEL, D. 2015. Establishment and growth of the White Tern Gygis alba population on Lord Howe Island, Australia. Marine Ornithology 43: 113-118.

CARLILE, N., PRIDDEL, D., LLOYD, C., JARMAN, M. & CRAVEN, P. 2015. Seabird islands No. 42/1: Tollgate Islands, New South Wales. Corella 39: 96-99.

DARLING, F.F. 1938. Bird flocks and the breeding cycle. Cambridge, UK: Cambridge University Press.

DIAS, M.P., MARTIN, R., PEARMAIN, E.J. ET AL. 2019. Threats to seabirds: A global assessment. Biological Conservation 237: 525-537.

DICKMAN, C.R., DALY, S.E.J. & CONNELL, G.W. 1991. Dietary Relationships of the Barn Owl and Australian Kestrel on Islands off the Coast of Western Australia. Emu 91: 67-72.

DOLIGEZ, B., CADET, C., DANCHIN, E. & BOULINIER, T. 2003. When to use public information for breeding habitat selection? The role of environmental predictability and density dependence. Animal Behaviour 66: 973-988.

FORD, R.G., TERRILL, S., CASEY, J. ET AL. 2021. Distribution patterns and population size of the Ashy Storm Petrel Oceanodroma homochroa. Marine Ornithology 49: 193-204.

FOWLER, J. 2002. European Storm-petrel (Storm Petrel) Hydrobates pelagicus. In: WERHAM, C., TOMS, M., MARCHANT, J., CLARK, J., SIRIWARDENA, G. & BAILLE, S. (Eds.) The Migration Atlas: Movements of the Birds of Britain and Ireland. London, UK: T & A. D. Poyser.

GARTHE, S., SCHWEMMER, P., PAIVA, V.H. ET AL. 2016. Terrestrial and marine foraging strategies of an opportunistic seabird species breeding in the Wadden Sea. PLoS One 11: e0159630. doi:10.1371/journal.pone.0159630

HARPER, G.A. 2007. Detecting predation of a burrow-nesting seabird by two introduced predators, using stable isotopes, dietary analysis and experimental removals. Wildlife Research 34: 443-453.

HIGGINS, P.J (Ed). 1999. Handbook of Australian, New Zealand and Antarctic Birds. Vol. 4: Parrots to Dollarbirds. Melbourne, Australia: Oxford University Press.

HOEG, R., SHUTLER, D. & POLLET, I.L. 2021. Levels of predation at two Leach's Storm Petrel Hydrobates leucorhous breeding colonies. Marine Ornithology 49: 119-125.

JOHNSTONE, R.E. & STORR, G.M. 1998. Handbook of Western Australian birds. Volume 1. Perth, Australia: Western Australian Museum.

JONES, H.P. & KRESS, S.W. 2012. A review of the world's active restoration projects. The Journal of Wildlife Management 76: 2-9.

KAVANAGH, R. 2004. Conserving owls in Sydney's urban bushland: current status and requirements. In: LUNNY, D. & BURGIN, S. (Eds.) Urban wildlife: more than meets the eye. Mosman, Australia: Royal Zoological Society of New South Wales.

KENWARD, R.E. 1999. Raptor predation problems and solutions. Journal of Raptor Research 33: 73-75.

KILDAW, S.D., IRONS, D.B., NYSEWANDER, D.R. & BUCK, C.L. 2005. Formation and growth of new seabird colonies: the significance of habitat quality. Marine Ornithology 33: 49-58.

LANE, B. 1976. Seabird islands No. 24: Bowen Island, Jervis Bay, New South Wales. Corella 14: 24-26.

LLOYD, C. & CARLILE, N. 2019. Seabird islands No. 39/1: Flinders Islet, Five Islands Group, New South Wales. Corella 43: 36-38.

MARCHANT, S. & HIGGINS, P.J., (Eds.) 1990. Handbook of Australian, New Zealand and Antarctic Birds. Vol.1: Ratites to Ducks. Melbourne, Australia: Oxford University Press.

MARTÍNEZ-GÓMEZ, J.E & JACOBSEN, J.K. 2004. The conservation status of Townsend's shearwater Puffinus auricularis. Biological Conservation 116: 35-47.

McIVER, W.R., HARVEY, A.L., CARTER, H.R., & HALPIN, L.R. 2011. Monitoring and restoration of Ashy Storm-Petrels at Santa Cruz Island, California, in 2010. Unpublished report. Arcata, California: US Fish and Wildlife Service, Arcata; Ventura, California: Channel Islands National Park; Victoria, Canada: Carter Biological Consulting; and Burnaby, Canada: Simon Fraser University.

McLAUGHLIN, J. 1994. Aspects of the Ecology and Behaviour of the Barn Owl Tyto alba (Scopoli) in the Mallee Wheat-belt of North-western Victoria, Australia. MSc thesis. Melbourne, Australia: La Trobe University.

MILLS, K. 2014. Photographic Guide to the Plants of Big Island, Five Islands Nature Reserve, Port Kembla. Illawarra Vegetation Studies 43. Jamberoo, Australia: Coachwood Publishing.

MILLS, K. 2016. Seabirds as part of migratory owl diet on Southeast Farallon Island, California. Marine Ornithology 44: 121-126.

MISKELLY, C.M. & TAYLOR, G.A. 2004. Establishment of a colony of Common Diving Petrels (Pelecanoides urinatrix) by chick transfers and acoustic attraction. Emu 104: 205-211.

MO, M. 2019. Occurrence of the Eastern Barn Owl Tyto alba delicatula in the Centennial Parklands, Sydney. Australian Field Ornithology 36: 56-59.

MOUGEOT, F. & BRETAGNOLLE, V. 2000. Predation risk and moonlight avoidance in nocturnal seabirds. Journal of Avian Biology 31: 376-386.

MOUGEOT, F., GENEVOIS, F. & BRETAGNOLLE, V. 1998. Predation on burrowing petrels by the brown skua (Catharacta skua lonnbergi) at Mayes Island, Kerguelen. Journal of Zoology 244: 429-438.

NSW NPWS (New South Wales National Parks and Wildlife Service). 2005. Five Islands Nature Reserve. Plan of management. Sydney, Australia: New South Wales National Parks and Wildlife Service.

NUR, N., BRADLEY, R. W., SALAS, L. WARZYBOK, P. & JAHNCKE, J. 2019. Evaluating population impacts of predation by owls on storm petrels in relation to proposed island mouse eradication. Ecosphere 10: e02878. doi:10.1002/ecs2.2878

O'DWYER, T., CARLILE, N., O'NEILL, L. & HALPIN, L.R. (2022). Changing fortunes of the Black-winged petrel Pterodroma nigripennis following the Lord Howe Island Rodent Eradication Project—interactions with other recovering species. Biological Invasions: in press.

PACEY, L. 2013. The Lure of Montague. Narooma, Australia: Laurelle Pacey.

PAREJO, D., ORO, D. & DANCHIN, E. 2006. Testing habitat copying in breeding habitat selection in a species adapted to variable environments. Ibis 148: 146-154.

POLLET, I.R. & SHUTLER, D. 2019. Effects of Great Horned Owls (Bubo virginianus) on a Leach's Storm-Petrel (Oceanodroma leucorhoa) population. The Wilson Journal of Ornithology 131: 152-155.

PRIDDEL, D., CARLILE, N., JARMAN, M., CRAVEN, P. & BLACKMORE, C.J. 2012. Seabird islands No. 26/1: Wasp Island, New South Wales. Corella 36: 47-49.

PRIDDEL, D. & CARLILE, N. 1995. Mortality of adult Gould's Petrel Pterodroma leucoptera at the nesting site on Cabbage Tree Island, New South Wales. Emu 95: 259-264.

PRIDDEL, D. & CARLILE, N. 1997. Conservation of the endangered Gould's petrel Pterodroma leucoptera. Pacific Conservation Biology 3: 322-329.

RAINE, A.F., YVNNE, M. & DRISKILL, S. 2019. Impact of an introduced avian predator, the Barn Owl Tyto alba, on Hawaiian seabirds. Marine Ornithology 47: 33-38.

RAINE, A.F., DRISKILL, S., YVNNE, M. HARVEY, D. & PIAS, K. 2020. Managing the effects of introduced predators on Hawaiian endangered seabirds. The Journal of Wildlife Management 84: 425-435.

RINGER, D., RUSSELL, J.C. & LE CORRE, M. 2015. Trophic roles of black rats and seabird impacts on tropical islands: mesopredator release or hyperpredation? Biological Conservation 185: 75-84.

SCHIPPERS, P., STIENEN, E.W.M., SCHOTMAN, A.G.M., SNEP, R.P.H. & SLIM, P.A. 2011. The consequences of being colonial: Allee effects in metapopulations of seabirds. Ecological Modelling 222: 3061-3070.

SHEALER, D.A. 2002. Foraging behaviour and food of seabirds. In: P. L. LUTZ (Ed.) Biology of Marine Birds. Baton Rouge, USA: CRC Press.

SMITH, G.C. & CARLILE, N. 1992. Silver Gull breeding at two colonies in the Sydney-Wollongong Region, Australia. Wildlife Research 19: 429-441.

TASKER, M.L. 2002. Little Tern. In: WERHAM, C., TOMS, M., MARCHANT, J., CLARK, J., SIRIWARDENA, G., and BAILLE, S. (Eds.) The Migration Atlas: Movements of the Birds of Britain and Ireland. London, UK: T & A. D. Poyser.

UNDERWOOD, M. & BUNCE, A. 2004. The breeding biology of the White-faced Storm Petrel (Pelagodroma marina) on Mud Island, Port Phillip Bay, Victoria. Emu 104: 213-220.

VELARDE, E., AVILA-FLORES, R. & MEDELLIN, R.A. 2007. Endemic and introduced vertebrates in the diet of a Barn Owl (Tyto alba) on two islands in the Gulf of California, Mexico. The Southwestern Naturalist 52: 284-290.

VOTIER, S.C., BEARHOP. S., RATCLIFFE, N., PHILLIPS, R.A. & FURNESS, R.W. 2004a. Predation by great skuas at a large seabird colony. Journal of Applied Ecology 41: 1117-1128.

VOTIER, S.C., FURNESS, R.W., BEARHOP, S. ET AL. 2004b. Changes in fisheries discard rates and seabird communities. Nature 427: 727-730.

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