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. predatory fish, marine reptiles, 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.
Nutritional ecology of Australasian gannets (Morus serrator) in Farewell Spit, New Zealand
Nutritional ecology of green sea turtles (Chelonias mydas) in Southwestern Pacific
Nutritional ecology of Brown boobies on Great barrier reef, Australia
Nutritional ecology of white sharks (Carcharodon carcharias) in NSW coastal waters
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.
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.
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.
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.