Aquarium Based Research Projects

To fulfil the Shark Lab’s mission statement we are an active participant in the ORI (Oceanographic Research Institute) tag and release scheme. As part of the program the Shark Lab aims to establish baseline data including relative abundance, species and size composition, growth rates, sex ratios, habitat utilisation and preference, spatial and temporal distribution, seasonal variation, residency and site fidelity, individual recognition, survival, mortality and recruitment, recapture rates for catsharks and monitor these shifts as potential anthropogenic modifications and developments take place within the bay.

This project aims to address major gaps in our understanding of the phenomenon of tonic immobility (TI) or death feigning. It is known to occur widely throughout the animal kingdom. However, the biological significance of the response in elasmobranchs remains uncertain. Investigating the average induction time, duration time, and its success aims to determine if these factors are independent of species and gender for various endemic catsharks. Data obtained from the research project will attempt to develop fuller comprehension of evolutionary importance of this response in elasmobranchs.

Defining species specific weight to length ratios helps to manage, regulate and maintain specimen health, against the manifestation of the two extreme conditions, anorexia and obesity, indicative of failing to meet basic dietary requirements. Feeding ration is dependent on many factors, and is therefore, not universally applicable under all circumstances and requires empirical adjustment. By establishing length-weight (L-W) equations for sharks held within the Wet Lab, and from healthy wild caught individuals, it will become a simple matter of entering a target length into a database to establish the relative health of long term captive individuals. Based on the length weight ratio and future feeding rations can be adjusted accordingly.

Anaesthetics are widely adopted in surgical, field sampling, and during experimental procedures. The only U.S. Food and Drug Administration's (FDA) approved fisheries aesthetic, tricaine methane sulfonate (MS-222), a water-soluble narcotic, is limited by its high cost and mandatory withdrawal period. Eugenol (clove oil) has emerged as a potentially, cheap, readily available and easy to handle alternative. To date most research detailing its use and application has been focused on non-elasmobranch species. The variability in behavioural responses to an anaesthetic depends on many factors. It is imperative to develop reliable dosages, administration methods and procedures in the use of analgesics to ensure their effectiveness and reliably. The knowledge of appropriate anaesthetic use when applied to sharks is invaluable and there exists a requirement to research and develop a drug anaesthetic implementation program and formally describe and disseminate information pertaining to the use of eugenol as an analgesic in elasmobranchs..

For apex predators, studies of food rations, food retention times, and food passage rates are an important component in many ecological studies. The nature of such investigations largely necessitates research within captive environments. Such experiments are essential for bioenergetic studies, by adopting targeted feeding, in combination with detailed record keeping, estimates of daily ration and subsequent growth rates can be relatively easily monitored.

In addition monitoring voluntary feeding frequency, following satiation, can be adopted as a proxy for gastric evacuation time (or retention time). Observing the time between feeding events over a range of artificially manipulated temperatures can be used to observe how temperature affects transit time in catsharks based on the Q10 temperature coefficient principle.