Md. Shamim Ahasan (PhD Research)
A survey of the bacterial gut communities of healthy and compromised green turtles (Chelonia mydas) and investigation into the cause and treatment for gastrointestinal disorders
Shamim’s research focused on investigating bacterial gut flora (normal and pathogenic) in healthy and compromised green sea turtle (Chelonia mydas) using both traditional culture dependent and independent diversity profiling techniques. Green sea turtles are hind gut fermenters which means they rely on ‘good’ bacteria in their gut for digestion. Shamim’s ultimate goal was to trial a new method for treating pathogenic bacteria that is highly targeted, so the ‘good’ bacteria will survive and benefit the turtles. This method is called bacteriophage therapy and could be an effective alternative to antibiotics and can be applied in both animal and human diseases.
Rebecca Hall (MSc Research)
Green turtle hatchlings (Chelonia mydas): do they have a favourite colour?
Rebecca’s project aimed to determine if green turtles can differentiate colour and if they have a preference. One possible use for understanding colour vision in green turtles could be finding one particular colour that elicits negative behaviour, for example swimming away from an object or refusing to interact with it.
Danielle Riethmiller (MSc Research)
Establishing baseline behaviour and responses to environmental enrichment with post-hatchling green turtles (Chelonia mydas)
This project aimed to produce an ethogram of behaviours for captive post-hatchling green turtles and measure responses to various environmental enrichment techniques. This data will allow us to measure responses to introduced enrichment items.
Alexandra Caron-Strehlow (MSc Research)
Development of a protocol to extract microplastics from green turtle gut content
Ingestion of plastic debris by sea turtles has been widely documented; however, contamination by microplastics (<5 mm) is poorly known. This project’s aim was to develop a microplastic extraction protocol for examining green turtle (Chelonia mydas) chyme. The chyme is a heterogeneous composite of various organic dietary items (e.g. seagrass, jellyfish), and incidentally-ingested inorganic materials (e.g. sediment). Preliminary results from the analysis of samples from two green turtles from the Great Barrier Reef revealed two macroplastics (a 4.5 m-long line and soft debris) in one turtle and seven microplastics (two plastic paint chips and five synthetic fabric particles) in the other. These results highlight the need for analysis of an increased sample size in order to improve our knowledge of the microplastic load of sea turtles from around the world. The sequential extraction protocol validated in this study will enable researchers worldwide to quantify green turtles microplastic contamination in a reliable and comparable way.
Alessandro Delli Paoli Carini (Honours Research)
Antibiotic resistant bacterial isolates from captive green turtles and in vitro sensitivity to bacteriophages
The increasing quantities of antibiotics released in the environment due to anthropogenic activities are selecting for resistant bacterial strains. Furthermore, broad-spectrum antibiotics can further jeopardise the health of hospitalised green turtles (Chelonia mydas) by killing the intestinal bacterial flora on which they rely for hind-gut fermentation. Alessandro investigated the presence of antibiotic resistant bacteria in hospitalised green turtles and in coastal environments and suggested the use of bacteriophages (tiny viruses that parasitise bacteria) as an alternative treatment for bacterial infections. This research found a strong presence of antibiotic-resistant bacterial strains in hospitalised green turtles and in their coastal environments, which will require further investigations.
Jonathan Meddings (Honours Research)
Revelations in reptilian immunology: serology and sources of variation
Freshwater turtles can act as reservoirs of infection and serve as a valuable indicator species for overall ecosystem health. One of the ways the health of freshwater turtles can be monitored is by testing their blood to detect a current or recent infection. This is called a serological survey. For his honours project, Jonathan collected blood from hundreds of freshwater turtles across Queensland and tested it for antibodies against a virus called Bohle iridovirus of the genus Ranavirus. Antibodies are proteins the immune system makes to fight infection. Jonathan’s work highlighted the importance of accounting for seasonal variation in immune responses when conducting serological surveys of reptiles.