Research Projects

Translating nutritional ecology from the laboratory to the field

Within my contributions to the field of nutritional ecology, I have been developing novel techniques to translate and expand well-established laboratory-based nutritional concepts using nutritional geometry to a challenging field-based approach using free-ranging organisms. The foundations of this work are reflected in frameworks for research in nutritional ecology in marine and terrestrial environments.

In order to better understand foraging decisions in free-ranging animals, I pioneered work linking cutting-edge miniaturise cameras and GPS developed by an engineering team under my lead. With collaborators and students, we deployed cameras in free-ranging (e.g. kangaroos, seabirds and dolphins) and semi-captive species (e.g. dogs and cows).

This project includes work that established a benchmark to unravel the amount of nutrients consumed per foraging attempt by a wild marine predator. We have also become the first worldwide team to successfully develop and deploy a sensor integrated miniaturise camera in free-ranging dolphins that has attracted extensive media coverage, including a YouTube video with more than 18K views https://www.youtube.com/watch?v=KuMGWinKUkw.

Selected publications

Börger L, Bijleveld A, Fayet AL, Machovsky-Capuska GE, Patrick SC, Street GM, Vander Wal E (2020). Editorial: Biologging Special Feature. Journal of Animal Ecology, 89:6-15. doi:10.1111/1365-2656.13163.
Herbert CA, Dassis M, Pye M, Jones P, Leong PHW, Thomas G, Cope H, Jarman A, Hobbs R, Murray PE and Machovsky-Capuska GE (2020). Development of light-weight video-tracking technology for use in wildlife research: A case study on kangaroos. Australian Zoologist. doi:10.7882/AZ.2020.001.
Pearson H, Jones PW, Taelor PB, Stockin AK, Machovsky-Capuska GE (2019). A biologging perspective to the drivers that shape gregariousness in dolphins. Behavioural Ecology and Sociobiology, 73:155. doi:10.1007/s00265-019-2763-z.
Pearson H, Jones P, Srinivasan M, Lundquist D, Pearson C, Stockin AK, Machovsky-Capuska GE (2017). Animal-borne video cameras as a tool for unraveling hidden behaviours in wild small cetaceans. Marine Biology. 164:42. doi: 10.1007/s00227-017-3079-z.
Pearson H, Machovsky-Capuska GE (2017). The secret life of dolphins. Australasian Science, 38:32-35.
Bombara C, Dürr S, Machovsky-Capuska GE, Jones P, Ward MP (2017). A preliminary study to estimate contact rates between free-roaming domestic dogs using novel miniature cameras. PLoS One, 12:7. doi:10.1371/journal.pone.0181859.
Machovsky-Capuska GE, Priddel D, Leong PHW, Jones P, Carlile N, Shannon L, Portelli D, McEwan A, Chaves A, Raubenheimer D (2016). Coupling bio-logging with nutritional geometry to reveal novel insights into the foraging behaviour of a plunge-diving marine predator. New Zealand Journal of Marine and Freshwater Research, 50:418-432. doi: 10.1080/00288330.2016.1152981. Photo Journal cover.

A nutritional perspective on plastic and heavy metal intake in wildlife

Although the perils of plastics to living organisms including humans have been neglected for decades, they have recently been recognized as a major environmental problem worldwide. Little progress has been made on understanding the factors that drive species’ and populations’ susceptibilities to the ingestion of plastic and heavy metals intake. Here, we propose using nutritional ecology as a multidisciplinary framework for bridging the gaps that link nutrition, behavior, plastics, heavy metals, physiology and ecology. We show that nutritional niches are tightly linked to plastic ingestion and heavy metals, illustrating the application of our framework in the context of nutritional niche theory, habitat-specific foraging from species to populations, and transfer patterns in food webs.

Plastic ingestion and nutritional ecology of green turtles (Chelonia mydas) along the South American Atlantic coast

Collaborator: Robson Guimarães Santos and Ryan Andrades

Nutritional ecology and heavy metals intake of common dolphins (Delphinus delphis) from northern Argentina

Collaborators: Marcela Gerpe and Diego Rodriguez

Selected publications

Machovsky-Capuska GE, Andrades, R Santos RG (2020). Debris ingestion and nutritional niches in estuarine and reef green turtles. Marine Pollution Bulletin. 153:110943. doi:10.1016/j.marpolbul.2020.110943.
Machovsky-Capuska GE, Amiot C, Denuncio P, Grainger R, Raubenheimer D (2019). A nutritional perspective on plastic ingestion in wildlife. Science of the Total Environment, 656: 789-796. doi: 10.1016/j.scitotenv.2018.11.418.

Nutrition in complex marine environments

An important goal for marine ecologists is to decipher the ecological factors that influence marine organisms’ abundance, diversity, social behaviour, all of which are underpinned by feeding behaviour. Operating in such a complex environment, marine species require particularly sophisticated foraging strategies that could enable them to survive and thrive. However, our knowledge on their food requirements, food selection and nutrition is limited.

Our understanding of marine organisms’ nutrition plays a pivotal role in theoretical and applied ecology, conservation, management and evolution and yet remains poorly characterized at different scales.

These multidisciplinary projects aim to understand the nutrient requirements, niche breath and foraging goals of marine organisms as a tool to predict how they will respond to marine pollution, anthropogenic pressures and environmental changes.

Research projects

Nutritional ecology of white sharks (Carcharodon carcharias) in NSW coastal waters, Australia

Collaborators: Vic Peddemors and David Raubenheimer

Nutritional ecology of coral reef fishes from Great barrier reef, Australia

Collaborator: Michael Kingsford

Nutritional ecology of Australasian gannets (Morus serrator) in Farewell Spit, New Zealand

Collaborators: Rob Schuckard, David Raubenheimer and David Melville

Nutritional ecology of marine mammals from northern Argentina

Collaborators: Pablo Denuncio, Mariela Dassis and Diego Rodriguez

Nutritional ecology of seabirds on Great barrier reef, Australia

Collaborators: Brad Congdon and Mark Miller

Selected publications

Machovsky-Capuska GE, Raubenheimer D (2020). Nutritional Ecology of Vertebrate Marine Predators. Annual Review of Marine Science. Invited manuscript, 12:361-387. doi:10.1146/annurev-marine-010318-095411

The role of Nutrition in invasive species

Many researchers have drawn crucial insights from species invasions, underlining animal behaviour as an essential component of invasion biology. High adaptations to new environments, dispersal ability, gregariousness and generalism have been suggested to enhance their invasiveness.

During the invasion process, animals are likely to be confronted with unfamiliar foods. Thus, the ability to subsist in different environments is linked to the challenges of ingesting, digesting, and assimilating a combination of foods that provide the required amounts and ratios of macronutrients (protein, lipid, and carbohydrates).

This multidisciplinary project aims to gain innovative insights in the role of nutrition in invasion success. Using common myna birds as a model system, we are examining a number of nutritional factors that could drive invasion success, including the role of nutritional balance, the importance of protein quality and availability and energy consumption.

Selected publications

Machovsky-Capuska GE, Senior AM, Simpson SJ, Raubenheimer D (2016). The Multi-dimensional Nutritional Niche. Trends in Ecology and Evolution, 31:355-365. doi: 10.1016/j.tree.2016.02.009.
Senior AM, Grueber CE, Machovsky-Capuska GE, Simpson SJ, Raubenheimer D (2016). Macronutritional consequences of Food Generalism in an Invasive Mammal, the Wild Boar. Mammalian Biology, 81:523-526. doi: 10.1016/j.mambio.2016.07.001.

Nutritional Ecology of urban avian species

Urbanization is characterized by the substitution of natural vegetation by man-made structures that may alter the abundance and species richness of native insects. Urban environments provide access to artificial breeding sites and anthropogenic foods (high in lipids and carbohydrates), which support a variety of native and invasive birds.

These ecosystems are also known to contain a wide range of macronutrient combinations that are influenced by human activities. In combination with a potential reduction in the availability of natural foods such as insects, urban birds may experience a mismatch between protein demand and its availability.

In a multidisciplinary collaboration, we are investigating the potential effects (e.g. community, population and individual level) of the nutritional quality of foods offered in supplementary feeding events.

Selected publications

Machovsky-Capuska GE, Senior AM, Simpson SJ, Raubenheimer D (2016). The Multi-dimensional Nutritional Niche. Trends in Ecology and Evolution, 31:355-365. doi: 10.1016/j.tree.2016.02.009.
Machovsky-Capuska GE, Senior AM, Zantis S, Barna K, Cowieson A, Pandya S, Pavard C, Shiels M, Raubenheimer D (2016). Dietary protein selection in a free-ranging urban population of common myna birds. Behavioral Ecology, 27:219-227. doi: 10.1093/beheco/arv142.