Research Projects

Nutrition in Marine predators

The foraging challenge for predators is to find and capture food with adequate levels of energy and nutrients. Marine predators (e.g. seabirds and marine mammals) forage in a complex nutritional environment in which prey is sparse and patchily distributed and are subject to oceanic and climatic fluctuations, as well as additional human pressures.

Successful predators require particularly sophisticated foraging strategies that enable them to balance self- and offspring-feeding, and also in many circumstances simultaneously consider the nutritional constraints of their partners.

This multidisciplinary project aims to understand the nutrient requirements and foraging goals of marine predators as a tool to predict how they will respond to environmental changes in prey availability.

Selected publications

Pearson H, Jones P, Srinivasan M, Lundquist D, Pearson C, Stockin AK, Machovsky-Capuska GE (2017). Animal-borne video cameras as a tool for unravelling hidden behaviours in wild small cetaceans. Marine Biology. 164:42. doi: 10.1007/s00227-017-3079-z.

Machovsky-Capuska GE, Coogan SCP, Simpson SJ, Raubenheimer D (2016). Motive for killing: what drives prey choice in wild predators? Ethology, 122:703-711. doi: 10.1111/eth.12523.

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.

Machovsky-Capuska GE, Senior AM,  Benn E, Tait AH, Schuckard R, Stockin KA, Cook W, Ogle M, Barna K, Melville D, Wright B, Purvin C, Raubenheimer D (2016). Sex-specific macronutrient foraging strategies in a successful marine predator: the Australasian gannet. Marine Biology, 163:75. doi: 10.1007/s00227-016-2841-y.

Tait A, Raubenheimer D, Stockin KA, Merriman M, Machovsky-Capuska GE (2014). Nutritional geometry and the macronutrient variation in the diet of gannets: the challenges in marine field studies. Marine Biology. 12: 2791-2801. doi: 10.1007/s00227-014-2544-1.

 

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 thus 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.