Project Manta is a multidisciplinary research aiming to describe the population biology, ecology and migrations of manta rays in eastern Australia.
Current research projects
Conservation biology and ecology of the population of manta ray, Manta alfredi, in eastern Australia
Despite the popular interest worldwide for manta rays, very little is known about their biology and ecology. Knowledge of their distribution and movement patterns is vital for conservation purposes. The reef manta, Manta alfredi, is known to occur and aggregate at several locations along the eastern Australian coast. However, information on the distribution, movement and biology of M. alfredi in eastern Australia is not well understood.
This PhD project focuses on the population ecology and biology of manta rays off the east Australian coast. It aims to provide important information on the life history of the manta ray population in eastern Australia, needed for conservation purposes. The main aspects investigated are: the population ecology (population size, structure and distribution), their habitat use at aggregation sites, the feeding ecology (diet composition, feeding behaviour, preys nutritional quality etc) and the cleaning ecology (cleaning fishes species, parasites, cleaner fish segregation, cleaning stations).
Methodologies for this research include photo-identification of manta rays, behavioural field observations, nutritional analysis, acoustic telemetry and zooplankton sampling.
This project largely relies and encourages the community participation with data collection (i.e. manta rays photographs and video recording, anecdotal reports).
Movements of marine megafauna and links to ocean dynamics and productivity: A case study of east Australian manta rays
Movements of marine megafauna have been shown to be mostly dictated by factors such as food, reproduction or particular oceanographic features. In east Australia, the newly re-described species of manta ray, Manta alfredi, seasonally undergoes large-scale migrations along the coast to aggregate at specific sites. Reasons behind such movements remain unknown. This research explores the links between regional ocean dynamics, primary and secondary productivity, and the movements and distributions of zooplanktivorous marine megafauna, using M. alfredi as a model species. Through a multi-disciplinary approach, Fabrice focuses at examining: 1) the spatio-temporal changes in oceanographic conditions at broad and fine spatial resolutions (through field-based measurements and satellite remote sensing); 2) phytoplankton biomass as a proxy of food availability for M. alfredi (using chlorophyll-a concentration and fluorescence as surrogate
measurements); 3) food resources (zooplankton biomass andcommunity composition); and 4) their relation to the ecology of a large pelagic vertebrate (movements and behaviour of M. alfredi). This project will lead to the creation of a planktivore state-space model, using manta rays as a model species, and that will provide a benchmark from which movements and distributions of other megafaunal species can be modelled, including the larger oceanic manta ray species Manta birostris, devil rays and planktivorous sharks (e.g. whale shark, megamouth shark, basking shark).