Dr Thomas Mattern, Our People, Department of Zoology

Email: t.mattern@eudyptes.net
Website: https://www.tawaki-project.org

Research Interests

I am a movement ecologist and for the past 20 years have been applying various bio-logging and wildlife telemetry technologies to study the at-sea behaviour of seabirds. My work also encompasses demography and population dynamics as well as physiological consequences of human disturbance on wildlife. I focus primarily on New Zealand penguins and have worked with all our endemic species but have also contributed to other seabird research in South America, Australia, Antarctica, and the Russian Arctic. Together with my wife Ursula Ellenberg I lead the Tawaki Project (www.tawaki-project.org), a long-term study of Fiordland penguins/tawaki and other crested penguins. I am also the chair of the charitable Tawaki Trust which aims at improving our understanding and conservation of New Zealand's crested penguin species.

Current Projects

Foraging ecology and population dynamics of Fiordland penguins/tawaki across their distributional range
Utilization of the marine habitat by Yellow-eyed penguins/hoiho on the New Zealand mainland and examination of potential fisheries interactions
Climate-related effects on the at-sea behaviour and population developments of Erect-crested and Eastern Rockhopper penguins
Foraging ecology of Humboldt penguins in northern Chile: what are potential and actual effects of increased coastal developments?

Publications

Dabkowski, O., Ellenberg, U., Mattern, T., Pütz, K., & Garcia Borboroglu, P. (2025). Correction factors for prey size estimation from PenguCams. PeerJ, 13. Advance online publication. doi: 10.7717/peerj.18598 Journal - Research Article

Mattern, T., Ellenberg, U., Pütz, K., Garcia Borboroglu, P., Seed, R., Houston, D., & Seddon, P. J. (2024). Beyond the horizon: A closer look at the Tawaki winter dispersal. New Zealand Journal of Zoology, (pp. 1). Advance online publication. doi: 10.1080/03014223.2024.2370252 Conference Contribution - Published proceedings: Abstract

Ellenberg, U., & Mattern, T. (2024). Breath-taking insights from recent camera deployments on New Zealand penguins. New Zealand Journal of Zoology, (pp. 1). Advance online publication. doi: 10.1080/03014223.2024.2370252 Conference Contribution - Published proceedings: Abstract

Hickcox, R., van Heezik, Y., Mattern, T., Rodríguez Recio, M., Young, M., & Seddon, P. (2024). Marine distribution of yellow-eyed penguins (Megadyptes antipodes): Presence and preference. New Zealand Journal of Zoology, (pp. 1). Advance online publication. doi: 10.1080/03014223.2024.2370252 Conference Contribution - Published proceedings: Abstract

Ellenberg, U., Daigre Valdés, M., Mattern, T., & Simeone, A. (2024). PenguCams reveal flexible foraging behaviour in Humboldt penguins: Good news for population resilience? New Zealand Journal of Zoology, (pp. 12). Advance online publication. doi: 10.1080/03014223.2024.2332118 Conference Contribution - Published proceedings: Abstract

2025

Journal - Research Article

2024

Conference Contribution - Published proceedings: Abstract

Mattern, T., Pütz, K., Mattern, H., Houston, D., Long, R., Keys, B., … Ellenberg, U., & Garcia-Borboroglu, P. (2024). A rock and a hard place: Are the subantarctic Bounty Islands becoming the new species stronghold for erect-crested penguins? New Zealand Journal of Zoology, (pp. 11-12). Advance online publication. doi: 10.1080/03014223.2024.2332118

Mattern, T., Pütz, K., Mattern, H., Houston, D., Long, R., Keys, B., … Ellenberg, U., & Garcia-Borboroglu, P. (2024). Continued population decline in erect-crested penguins at the Antipodes. New Zealand Journal of Zoology, (pp. 10-11). Advance online publication. doi: 10.1080/03014223.2024.2332118

Hornblow, B., Mattern, T., Ellenberg, U., White, J., & Wing, S. (2024). Foraging ecology of tawaki (Fiordland penguin) in Doubtful Sound. New Zealand Journal of Zoology, (pp. 9-10). Advance online publication. doi: 10.1080/03014223.2024.2332118

Hickcox, R., van Heezik, Y., Young, M., Rodríguez-Recio, M., Mattern, T., & Seddon, P. (2024). Resources, risks and refugia: Assessing the spatial overlap between yellow-eyed penguin foraging distribution, prey, commercial ﬁsheries, and marine protected areas. New Zealand Journal of Zoology, (pp. 3-4). Advance online publication. doi: 10.1080/03014223.2024.2332118

2023

Journal - Research Article

Mattern, T., Pütz, K., Mattern, H. L., Houston, D. M., Long, R., Keys, B. C., … Ellenberg, U., & Garcia-Borboroglu, P. (2023). Accurate abundance estimation of cliff-breeding Bounty Island shags using drone-based 2D and 3D photogrammetry. Avian Conservation & Ecology, 18(2), 6. doi: 10.5751/ACE-02496-180206

Hickcox, R. P., Mattern, T., Young, M. J., Rodríguez-Recio, M., van Heezik, Y., & Seddon, P. J. (2023). Risks, resources, and refugia: Spatial overlap between yellow-eyed penguin foraging distribution and prey, commercial fisheries, and marine protected areas. Biological Conservation, 284, 110197. doi: 10.1016/j.biocon.2023.110197

Harris, S., Pütz, K., Mattern, T., Scioscia, G., & Rey, A. R. (2023). The role of conspecifics during pelagic foraging of Magellanic and benthic foraging of Gentoo penguins in the Beagle Channel, Argentina. Marine Biology, 170, 17. doi: 10.1007/s00227-022-04163-3

Journal - Research Other

White, J., Mattern, T., Pütz, K., Mattern, H., Houston, D., Long, R., Keys, B. C., Ellenberg, U., & Garcia-Borboroglu, P. (2023). Plumage colour aberrations in erect-crested penguins (Eudyptes sclateri) on Antipodes Island [Short note]. Notornis, 70(3), 143-146.

2022

Journal - Research Article

Davis, L. S., Renner, M., Houston, D., Zhu, L., Finkler, W., & Mattern, T. (2022). The breeding biology of erect-crested penguins, Eudyptes sclateri: Hormones, behavior, obligate brood reduction and conservation. PLoS ONE, 17(10), e0275106. doi: 10.1371/journal.pone.0275106

Hickcox, R. P., Mattern, T., Rodríguez-Recio, M., Young, M. J., van Heezik, Y., & Seddon, P. J. (2022). Staying close to home: Marine habitat selection by foraging yellow-eyed penguins using spatial distribution models. Frontiers in Marine Science, 9, 967741. doi: 10.3389/fmars.2022.967741

Young, M. J., Seddon, P. J., Pütz, K., Agnew, P., Mattern, T., Hickcox, R. P., Robertson, B. C., & van Heezik, Y. (2022). Conservation implications for post-fledging dispersal of yellow-eyed penguins/hoiho. Marine Ecology Progress Series, 695, 173-188. doi: 10.3354/meps14124

Cole, T. L., Zhou, C., Fang, M., Pan, H., Ksepka, D. T., Fiddaman, S. R., … Grosser, S., … Mattern, T., … Ellenberg, U., … Zhang, G. (2022). Genomic insights into the secondary aquatic transition of penguins. Nature Communications, 13, 3912. doi: 10.1038/s41467-022-31508-9

Elley, T., Mattern, T., Ellenberg, U., Young, M. J., Hickcox, R. P., van Heezik, Y., & Seddon, P. J. (2022). Consistent site-specific foraging behaviours of yellow-eyed penguins/hoiho breeding on Stewart Island, New Zealand. Biology, 11, 844. doi: 10.3390/biology11060844

Green, C.-P., Ratcliffe, N., Mattern, T., Thompson, D., Lea, M.-A., Wotherspoon, S., … Ellenberg, U., … Seddon, P. J., … Hindell, M. A. (2022). The role of allochrony in influencing interspecific differences in foraging distribution during the non-breeding season between two congeneric crested penguin species. PLoS ONE, 17(2), e0262901. doi: 10.1371/journal.pone.0262901

2021

Journal - Research Article

White, J., Mattern, T., Ellenberg, U., Garcia-Borboroglu, P., Houston, D. M., Seddon, P. J., & Mays, H. L. (2021). Field sexing techniques for Fiordland crested penguins (tawaki; Eudyptes pachyrhynchus). Notornis, 68(3), 188-193. Retrieved from http://notornis.osnz.org.nz/node/4558

Masello, J. F., Barbosa, A., Kato, A., Mattern, T., Medeiros, R., Stockdale, J. E., … Quillfeldt, P. (2021). How animals distribute themselves in space: Energy landscapes of Antarctic avian predators. Movement Ecology, 9, 24. doi: 10.1186/s40462-021-00255-9

Mattern, T., Rexer-Huber, K., Parker, G., Amey, J., Green, C.-P., Tennyson, A. J. D., … Thompson, D. R. (2021). Erect-crested penguins on the Bounty Islands: Population size and trends determined from ground counts and drone surveys. Notornis, 68(1), 37-50.

2020

Journal - Research Article

Harris, S., Scioscia, G., Klemens, P., Mattern, T., & Rey, A. R. (2020). Niche partitioning between coexisting gentoo Pygoscelis papua and Magellanic penguins Spheniscus magellanicus at Martillo Island, Argentina. Marine Biology, 167(8), 105. doi: 10.1007/s00227-020-03722-w

2019

Journal - Research Article

Cole, T. L., Dutoit, L., Dussex, N., Hart, T., Alexander, A., Younger, J. L., … Ellenberg, U., … Mattern, T., … Waters, J. M. (2019). Receding ice drove parallel expansions in Southern Ocean penguins. PNAS, 116(52), 26690-26696. doi: 10.1073/pnas.1904048116

Cole, T. L., Rawlence, N. J., Dussex, N., Ellenberg, U., Houston, D. M., Mattern, T., … Waters, J. M. (2019). Ancient DNA of crested penguins: Testing for temporal genetic shifts in the world's most diverse penguin clade. Molecular Phylogenetics & Evolution, 131, 72-79. doi: 10.1016/j.ympev.2018.10.025

Journal - Research Other

Pan, H., Cole, T. L., Bi, X., Fang, M., Zhou, C., Yang, Z., … Mattern, T., … Young, M. J., … Grosser, S., … Zhang, G. (2019). High-coverage genomes to elucidate the evolution of penguins [Data note]. GigaScience, 8(9), giz117. doi: 10.1093/gigascience/giz117

Conference Contribution - Published proceedings: Abstract

Cole, T., Dutoit, L., Dussex, N., Hart, T., Alexander, A., Frugone, M. J., … Ellenberg, U., … Mattern, T., … Waters, J. (2019). Receding ice drove rapid expansions in eight Southern Ocean penguins. Proceedings of the Genetics Society of Australasia (GSA) Conference. Retrieved from https://event.crowdcompass.com/gsa2019

Young, M. J., Seddon, P. J., Pütz, K., Mattern, T., Robertson, B. C., & van Heezik, Y. (2019). Go forth and prosper? Post-fledging dispersal and the decline in juvenile survival of mainland yellow-eyed penguins. Proceedings of the 10th International Penguin Conference (IPC10). (pp. 96). Retrieved from https://www.penguin-conference.com

Mattern, T., Clarkson, G., Pütz, K., Garcia Borboroglu, P., Ellenberg, U., Houston, D., … Seddon, P. (2019). Marathon penguins: Reasons and consequences of long-range dispersal in Fiordland penguins/tawaki during the pre-moult period. Proceedings of the 10th International Penguin Conference (IPC10). (pp. 61). Retrieved from https://www.penguin-conference.com

White, J., Mattern, T., Ellenberg, U., Garcia-Borboroglu, P., Houston, D. M., Seddon, P., … Mays, H. (2019). Investigating Fiordland penguin (tawaki) dietary plasticity using stable isotope analysis. Proceedings of the 10th International Penguin Conference (IPC10). (pp. 75). Retrieved from https://www.penguin-conference.com

Young, M. J., Robertson, F., Dutoit, L., Mattern, T., Seddon, P. J., Robertson, B. C., & van Heezik, Y. (2019). Evidence for declining diet quality of mainland yellow-eyed penguins (Megadyptes antipodes): Is this their final dive? Proceedings of the 10th International Penguin Conference (IPC10). (pp. 73). Retrieved from https://www.penguin-conference.com

Cole, T. L., Dutoit, L., Dussex, N., Hart, T., Alexander, A., Frugone, M. J., … Ellenberg, U., … Mattern, T., … Waters, J. M. (2019). Contrasting demographic histories between widespread and endemic penguin taxa. Proceedings of the 10th International Penguin Conference (IPC10). (pp. 39-40). Retrieved from https://www.penguin-conference.com

Hickcox, R. P., van Heezik, Y., Mattern, T., Young, M. J., & Seddon, P. J. (2019). Environmental, climatic, and biological interactions influencing the marine distribution of yellow-eyed penguins (Megadyptes antipodes). Proceedings of the 10th International Penguin Conference (IPC10). (pp. 36). Retrieved from https://www.penguin-conference.com

Ellenberg, U., Mattern, T., Houston, D., Long, R., Pütz, K., Garcia Borboroglu, P., & Seddon, P. (2019). Penguin plasticity: Surprisingly versatile marine life-style in Fiordland penguins/tawaki. Proceedings of the 10th International Penguin Conference (IPC10). (pp. 22). Retrieved from https://www.penguin-conference.com

Mattern, T., Ellenberg, U., Seed, R., van Heezik, Y., & Seddon, P. (2019). A birds-eye view on food: Using animal-borne cameras to study Yellow-eyed penguin foraging ecology. Proceedings of the 10th International Penguin Conference (IPC10). (pp. 18). Retrieved from https://www.penguin-conference.com

2018

Journal - Research Article

Mattern, T., McPherson, M. D., Ellenberg, U., van Heezik, Y., & Seddon, P. J. (2018). High definition video loggers provide new insights into behaviour, physiology, and the oceanic habitat of a marine predator, the yellow-eyed penguin. PeerJ, 6, e5459. doi: 10.7717/peerj.5459

Mattern, T., Pütz, K., Garcia-Borboroglu, P., Ellenberg, U., Houston, D. M., Long, R., … Seddon, P. J. (2018). Marathon penguins: Reasons and consequences of long-rage dispersal in Fiordland penguins/Tawaki during the pre-moult period. PLoS ONE, 13(8), e0198688. doi: 10.1371/journal.pone.0198688

Conference Contribution - Published proceedings: Abstract

Mattern, T., & Wilson, K.-J. (2018). Identifying conservation actions required to protect Tawaki in New Zealand. Proceedings of the Birds New Zealand Conference. (pp. 24). Retrieved from https://www.osnz.org.nz/

Wilson, K.-J., & Mattern, T. (2018). Identifying conservation actions required to protect Little Penguins in New Zealand. Proceedings of the Birds New Zealand Conference. (pp. 23-24). Retrieved from https://www.osnz.org.nz/

Mattern, T., Seed, R., Ellenberg, U., van Heezik, Y., & Seddon, P. (2018). Penguin-cams: Gaining a whole new perspective on the foraging ecology and marine habitat of Yellow-eyed penguins. Proceedings of the Birds New Zealand Conference. (pp. 16). Retrieved from https://www.osnz.org.nz/

Working Paper; Discussion Paper; Technical Report

Mattern, T., Ellenberg, U., Houston, D. M., & Davis, L. S. (2018). Like clockwork: Nest attendance patterns and foraging behaviour of Snares penguins Eudyptes robustus as a function of daylength and oceanography. PeerJ Preprints. doi: 10.7287/peerj.preprints.26653v1

Mattern, T., Pütz, K., Garcia-Borboroglu, P., Ellenberg, U., Houston, D., Long, R., … Seddon, P. J. (2018). Marathon penguins: Reasons and consequences of long-range dispersal in Fiordland penguins/Tawaki during the pre-moult period. PeerJ Preprints. doi: 10.7287/peerj.preprints.26527v1

2017

Journal - Research Article

Thiebot, J.-B., Arnould, J. P. Y., Gómez-Laich, A., Ito, K., Kato, A., Mattern, T., … Seddon, P. J., … Takahashi, A. (2017). Jellyfish and other gelata as food for four penguin species: Insights from predator-borne videos. Frontiers in Ecology & the Environment, 15(8), 437-441. doi: 10.1002/fee.1529

Meyer, X., MacIntosh, A. J. J., Chiaradia, A., Kato, A., Mattern, T., Sueur, C., & Ropert-Coudert, Y. (2017). Shallow divers, deep waters and the rise of behavioural stochasticity. Marine Biology, 164(6), 149. doi: 10.1007/s00227-017-3177-y

Mattern, T., Meyer, S., Ellenberg, U., Houston, D. M., Darby, J. T., Young, M., van Heezik, Y., & Seddon, P. J. (2017). Quantifying climate change impacts emphasises the importance of managing regional threats in the endangered Yellow-eyed penguin. PeerJ, 5, e3727. doi: 10.7717/peerj.3272

Journal - Research Other

Mattern, T., & Long, R. (2017). Survey and population size estimate of Fiordland penguin (tawaki; Eudyptes pachyrhynchus) in Milford Sound / Piopiotahi, New Zealand [Short note]. Notornis, 64, 97-101.

Conference Contribution - Published proceedings: Abstract

Mattern, T., Ellenberg, U., Garcia-Borboroglu, P., Pütz, K., Houston, D., & Seddon, P. (2017). The advantages of breeding in diverse habitats: Site-dependent effects of El Niño on foraging behaviour in Fiordland penguins/tawaki. New Zealand Journal of Zoology, 44(2), (pp. 170-171). doi: 10.1080/03014223.2016.1264079

Working Paper; Discussion Paper; Technical Report

Mattern, T., McPherson, M., Ellenberg, U., van Heezik, Y., & Seddon, P. J. (2017). High definition video loggers provide new insights into behaviour, physiology, and the oceanic habitat of marine top predators. PeerJ Preprints. doi: 10.7287/peerj.preprints.2765v1

2013

Chapter in Book - Research

Mattern, T. (2013). Snares penguin (Eudyptes robustus). In P. Garcia Borboroglu & P. D. Boersma (Eds.), Penguins: Natural history and conservation. (pp. 169-183). Seattle, WA: University of Washington Press.

Mattern, T. (2013). Fiordland penguin (Eudyptes pachyrhynchus). In P. Garcia Borboroglu & P. D. Boersma (Eds.), Penguins: Natural history and conservation. (pp. 153-167). Seattle, WA: University of Washington Press.

Journal - Research Article

Mattern, T., Ellenberg, U., Houston, D. M., Lamare, M., Davis, L. S., van Heezik, Y., & Seddon, P. J. (2013). Straight line foraging in yellow-eyed penguins: New insights into cascading fisheries effects and orientation capabilities of marine predators. PLoS ONE, 8(12), e84381. doi: 10.1371/journal.pone.0084381

Conference Contribution - Published proceedings: Abstract

Mattern, T., Ellenberg, U., Houston, D. M., Seddon, P. J., & Davis, L. S. (2013). The Pros and Cons of being a benthic forager: How anthropogenic alterations of the seafloor affect Yellow-eyed penguins [Keynote]. Proceedings of the 8th International Penguin Conference (IPC8). (pp. 16). Retrieved from https://www.penguin-conference.com

2012

Journal - Research Article

Ellenberg, U., Mattern, T., Houston, D. M., Davis, L. S., & Seddon, P. J. (2012). Previous experiences with humans affect responses of Snares Penguins to experimental disturbance. Journal of Ornithology, 153(3), 621-631. doi: 10.1007/s10336-011-0780-4

2011

Journal - Research Article

Browne, T., Lalas, C., Mattern, T., & van Heezik, Y. (2011). Chick starvation in yellow-eyed penguins: Evidence for poor diet quality and selective provisioning of chicks from conventional diet analysis and stable isotopes. Austral Ecology, 36(1), 99-108. doi: 10.1111/j.1442-9993.2010.02125.x

2010

Conference Contribution - Published proceedings: Abstract

Garcia-Borboroglu, P., Boersma, D., Trathan, P., Pütz, K., Wienecke, B., Le Maho, Y., … Mattern, T., … Ellenberg, U., Seddon, P., van Heezik, Y., … Davis, L., … Hindel, M. (2010). Penguin status in troubled oceans. In H. Urquhart, D. Laughlin & P. DiBona (Eds.), Proceedings of the 7th International Penguin Conference. (pp. 44). Boston, MA: New England Aquarium. [Abstract]

2009

Journal - Research Article

Mattern, T., Houston, D. M., Lalas, C., Setiawan, A. N., & Davis, L. S. (2009). Diet composition, continuity in prey availability and marine habitat: Keystones to population stability in the Snares Penguin (Eudyptes robustus). Emu, 109, 204-213. doi: 10.1071/mu08001

McGraw, K. J., Massaro, M., Rivers, T. J., & Mattern, T. (2009). Annual, sexual, size- and condition-related variation in the colour and fluorescent pigment content of yellow crest-feathers in Snares Penguins (Eudyptes robustus). Emu, 109(2), 93-99. doi: 10.1071/mu08034

Ellenberg, U., Mattern, T., & Seddon, P. J. (2009). Habituation potential of yellow-eyed penguins depends on sex, character and previous experience with humans. Animal Behaviour, 77(2), 289-296. doi: 10.1016/j.anbehav.2008.09.021

2007

Journal - Research Article

Mattern, T., Ellenberg, U., Houston, D. M., & Davis, L. S. (2007). Consistent foraging routes and benthic foraging behaviour in yellow-eyed penguins. Marine Ecology Progress Series, 343, 295-306. doi: 10.3354/meps06954

Chiaradia, A., Ropert-coudert, Y., Kato, A., Mattern, T., & Yorke, J. (2007). Diving behaviour of Little Penguins from four colonies across their whole distribution range: Bathymetry affecting diving effort and fledging success. Marine Biology, 151, 1535-1542. doi: 10.1007/s00227-006-0593-9

2006

Journal - Research Article

Ellenberg, U., Mattern, T., Seddon, P. J., & Jorquera, G. L. (2006). Physiological and reproductive consequences of human disturbance in Humboldt penguins: The need for species-specific visitor management. Biological Conservation, 133, 95-106.

2004

Journal - Research Article

Mattern, T., Ellenberg, U., Luna-Jorquera, G., & Davis, L. S. (2004). Humboldt penguin census on Isla Chañaral, Chile: Recent increase or past underestimate of penguin numbers? Waterbirds, 27(3), 368-376.