Marine Biology

, 164:82 | Cite as

Jack of all prey, master of some: Influence of habitat on the feeding ecology of a diving marine predator

  • Jonathan M. HandleyEmail author
  • Maëlle Connan
  • Alastair M. M. Baylis
  • Paul Brickle
  • Pierre Pistorius
Original paper


Marine species occupy broad geographical ranges that encompass varied habitats. Accordingly, resource availability is likely to differ across a species range and, in-turn, this may influence the degree of dietary specialization. Gentoo penguins Pygoscelis papua are generalist predators occupying a range of habitats with a large breeding range extending from Antarctica to temperate environments. Using the most extensive stomach content data set on gentoo penguins this study investigated their feeding ecology at the Falkland Islands (52°S, 59.5°W), the world’s largest population. Sampling occured in consecutive breeding seasons (2011–2013), across multiple foraging habitats utilizing stomach content data and carbon and nitrogen stable isotope values of feathers. The first species specific description of diet at this scale for the Falklands revealed six key prey items for the birds: rock cod (Patagonotothen spp.), lobster krill (Munida spp.), Falkland herring (Sprattus fuegensis), Patagonian squid (Doryteuthis gahi), juvenile fish (likely all nototheniids), and southern blue whiting (Micromesistius australis). Niche width, relating to both stomach content and stable isotope data related to the surrounding bathymetry. Birds from colonies close to gently sloping, shallow waters, fed primarily on benthic prey and had larger niche widths. The opposite was observed at a colony surrounded by steeply sloping, deeper waters. Therefore, gentoo penguins at the population level at the Falklands are indeed generalists, however, at individual colonies some specialization occurred to take advantage of locally available prey, resulting in these birds being classified as Type B generalists. Hence, future studies must account for this intra-colony variation when assessing for factors such as inter-specific competition or overlap with anthropogenic activities.


Prey Item Niche Width Gentoo Penguin Falkland Island Isotopic Niche 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This project was generously supported by the Rufford Small Grants Foundation, John Cheek Trust, Falkland Islands Environmental Planning Department and Nelson Mandela Metropolitan University Research Capacity Department. Additional stipends were provided by the National Research Foundation of South Africa. Special thanks to Zhanna Shcherbich and staff of the Falkland Islands Fisheries Department, and Dr. Yves Cherel (CNRS, France) for assistance in sample identification. Furthermore, thank you to Dr. Paul Brewin and staff on board the Falkland Islands Fisheries Department research cruises for collecting samples toward stable isotope analysis. We are grateful to the land owners (Wildlife Conservation Society, North Arm Farm and Johnsons Harbour) and wardens who provided access to study colonies and logistical support. We are extremely thankful to the volunteers who assisted with sample collection, with special mention to Jacki Bennett and David Schutt.

Compliance with ethical standards

Conflict of interest

The authors declare that there is no conflict of interest and that consent was obtained from all parties. The research was conducted under Grants from the Falkland Islands Environmental Planning Department: R17/2011 & R13/2012.

Human and animal ethics

Animal ethics approval was granted by Nelson Mandela Metropolitan University ethics committee (ALL-SCI-ZOO-014).

Supplementary material

227_2017_3113_MOESM1_ESM.pdf (1.9 mb)
Supplementary material 1 (PDF 1970 KB)


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Copyright information

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Authors and Affiliations

  1. 1.DST/NRF Centre of Excellence, Percy FitzPatrick Institute of African Ornithology, Department of ZoologyNelson Mandela Metropolitan UniversityPort ElizabethSouth Africa
  2. 2.Falklands ConservationStanleyFalkland Islands
  3. 3.The Icelandic Seal CenterHvammstangiIceland
  4. 4.South Atlantic Environmental Research InstituteStanleyFalkland Islands
  5. 5.Falkland Islands Government Fisheries DepartmentStanleyFalkland Islands
  6. 6.School of Biological Sciences (Zoology)University of AberdeenAberdeenUK

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