Juan F. Masello

Profile

My multidisciplinary areas of research focus on the behavioural ecology, and molecular ecology of wild populations of birds. My research topics include (1) responses of individuals to changing environmental conditions, (2) foraging strategies, (3) reproductive strategies, (4) individual reproductive performance, and (5) the evolutionary consequences of behaviour. My research is conducted on wild populations of parrots, penguins, gulls and petrels since these offer excellent opportunities for testing a number of theoretical predictions. I initiated and lead several projects among them the ‘Breeding biology of Burrowing Parrots’ (since 1998), and ‘How animals distribute themselves in space: energy landscapes of an Antarctic predator’ funded by the Deutsche Forschungsgemeinschaft (DFG) Priority Programme “Antarctic Research with comparative investigations in Arctic ice areas” SPP 1158.

Previous Research and Other Interests

Some highlights of my research include:

1) using Pachyptila prions (Aves, Procellariiformes), I have demonstrated how additive traits lead to feeding advantage and reproductive isolation, which promoted homoploid hybrid speciation (HHS); HHS has been found only a few times in animals, and I have shown for the first time that additivity of divergent parental traits alone can lead directly to increased hybrid fitness and reproductive isolation (Molecular Biology and Evolution); my current research expands on these results, now using whole genome sequencing, through a Deutsche Forschungsgemeinschaft (DFG) research grant (MA 2574/10-1);

2) using penguin species from Antarctica and the Falkland Islands, GPS and tri-axial-acceleration data, and next-generation sequencing (NGS) of prey remains, I have expanded the energy landscape approach to foraging research, which provides a detailed mechanistic basis of spatial ecology and decision making in animals; energy landscapes allowed me to link the quantification of the variation in the energy costs of movements through a given environment, as well as how these costs vary in time and between contrasting sites, with breeding success and the species’ population trend; I also showed that such link was mediated by the physiological condition of the individuals (Movement Ecology);

3) using GPS and tri-axial-acceleration data, and machine learning methods, I have been able to follow wild common woodpigeons for over two years, and being able to investigate year-round behavioural time budgets, and to identifying and classify crucial behaviours (foraging, flying, resting), an accomplishment achieved only a few times until now that opens several lines of future research in foraging ecology (Behavioral Ecology and Sociobiology);

4) investigating the presence of avian hemoparasites, with molecular methods, in 19 Psittaciformes from all over the planet, I showed that the consumption of food items known for their secondary metabolites with antimalarial, trypanocidal or general antiparasitic properties, explains the low prevalence of hemoparasites reported in many vertebrates (Parasites & Vectors).

5) In ecological studies, sampling must be stratified to ensure a sample population that best represents the entire population studied. Meta-analyses assessing global patterns should also use a stratified data structure to ensure unbiased results. We showed that this is generally not the case, as individual studies are heavily biased towards the Northern Hemisphere. We also showed that Southern Hemisphere birds offer insightful complementary models for ecological and evolutionary biology. We therefore pointed to the need for promoting research in the Southern Hemisphere to tackle fundamental questions with a global perspective (Trends in Ecology and Evolution).

These and other results from my research provide fundamental links among the individuals foraging behaviour, their response to changing environmental conditions, their reproductive performance, which allow a better understanding of the persistence of populations and the evolution of species in a changing world.

Curriculum Vitae
  • Since 2023: Research fellow (Wissenschaftlicher Mitarbeiter), Department of Animal Behaviour, Bielefeld University. Topic: Evolutionary mechanisms underlying divergence in bill morphology and the timing of breeding using whole genome analysis. Funding: Deutsche Forschungsgemeinschaft (DFG)
  • 2019–2022: Research fellow, Department of Animal Ecology & Systematics, Justus Liebig University Giessen (JLU Giessen). Topic: Movement ecology and microhabitat choice of medium-sized bird species (subproject ÖP3 within ‘Nature 4.0 – Sensing Biodiversity’ lead by the Philipps-Universität Marburg). Funding: The State of Hessen Ministry for Higher Education, Research and the Arts, LOEWE focus project.
  • 2015–2018: Research fellow, Department of Animal Ecology & Systematics, JLU Giessen. Topic: How animals distribute themselves in space: energy landscapes of an Antarctic predator. Funding: DFG-SPP1158 Antarctic Research
  • 2013–2015: Research fellow, Department of Animal Ecology & Systematics, JLU Giessen. Topics: How animals distribute themselves in space: changing energy landscapes; population genetics and spatial distribution of Burrowing Parrots in Patagonia. Funding: DFG
  • 2012–2013: Research fellow, Department of Animal Ecology & Systematics, JLU Giessen. Topics: molecular genetics of seabird evolution, foraging ecology and diving behaviour of seabirds in the Falkland Is. and San Benito Is. (México); behavioural ecology of Burrowing Parrots in Patagonia. Funding: DFG
  • 2012: Lecturer (Lehrkraft für besondere Aufgaben), JLU Giessen. BSc and MSc courses during the summer semester: Biodiversity and Systematics, Zoology, Animal Ecology, Anatomy, Systematics, and Evolution of Plants and Animals
  • 2010–2011: Research fellow, Max Planck Institute for Ornithology, Vogelwarte Radolfzell. Topics: foraging ecology and diving behaviour of seabirds in the Falkland Is. and San Benito Is. (Mexico); behavioural ecology of Burrowing Parrots in Patagonia. Funding: Max Planck Institute for Ornithology, DFG, and Wildlife Conservation Society (WCS, USA)
  • 2008–2010: Research fellow, Max Planck Institute for Ornithology, Vogelwarte Radolfzell Topics: foraging ecology and diving behaviour of seabirds in the Falkland Is.; behavioural ecology and phylogeography of Burrowing Parrots in Patagonia. Funding: Max Planck Institute for Ornithology, Vogelwarte Radolfzell, and WCS (USA)
  • 2006–2008: Project leader, (Leiter eines Drittmittelprojektes), Max Planck Institute for Ornithology, Vogelwarte Radolfzell. Funding: WCS (USA). Topics: breeding biology of Burrowing Parrots under variable environmental conditions and variable human disturbance; breeding biology of Thin-billed Prions; provisioning and growth patterns in seabirds; foraging ecology of Blue-eyed (King) shags
  • 2005–2006: Post-doctoral research, Max Planck Institute for Ornithology, Radolfzell. Topics: plumage coloration in relation to season, sex steroids, immune and other health parameters in songbirds; the ecological significance of parrot coloration
  • 2003–2004: Post-doctoral research, School of Biological Sciences, University of Bristol (UK). Topics: the ecological significance of parrot coloration: insights from the South American Burrowing Parrot; breeding biology of Thin-billed Prions; blood chemistry, nutrition and ectoparasites in Wilson’s Storm-petrels
  • 2002: Post-doctoral research, Institute of Biomedical and Life Sciences, University of Glasgow (UK). Topics: breeding biology of Burrowing Parrots; begging and chick provisioning in Cory’s Shearwaters; provisioning and begging regulation of feeding frequencies and meal sizes in Manx Shearwaters
  • 2002: Ph.D., Free University Berlin. Thesis: Breeding biology of Burrowing Parrots Cyanoliseus patagonus during contrasting environmental conditions. Supervisor: Prof Dr D Todt. Awarded magna cum laude. Complete thesis was published
  • 1998: M.Sc. University of Buenos Aires (Argentina). Thesis: Mechanisms of admixture of zooplanktonic molluscs in the Subtropical Front of the South Atlantic Ocean. Complete thesis was published
Publications

For a full list of publications see ResearchGate (link below) or pdf pdf.

Contact Details

Department of Animal Behaviour
Bielefeld University
Postfach 100131
33501 Bielefeld
Germany

researchgate: Juan Masello
orcid: Juan Masello