Dr. Rob Adlard is a parasitologist working at Queensland Museum.
Recently Rob has been on a quest of biodiscovery to uncover some of the ‘hidden diversity’ on coral reefs with an emphasis on fish parasites. Rob and his team have uncovered many species of myxosporean parasites, some of which are Kudoa spp., and these infect our reef fish. Here is an image of Rob, Dr Terry Miller, and PhD student Holly Heiniger in the waters off Lizard Island. They are collecting small cardinal fish using localised sprays of an anaesthetic while underwater.
A dissection of a snapper from the reef revealed white disc-like cysts on the meninges (membranes covering the brain) which are filled with myxosporean spores. These can be seen clearly in the image below. Each cyst is 1-2 mm in diameter and contains thousands of microscopic spores that appear like tiny flowers.
Clearly, we want to know what impact this parasite is having on the fish. Does it interfere with how the fish processes information? Does it impact on behaviour and so affect the survival of the fish?
In one species of cardinal fish the pericardial membrane (which surrounds the heart), was packed with cysts from another species of the Kudoa parasite. This is shown below.
What impact do these cysts have on the fish? Do they stunt the growth of the fish? Do they affect reproduction? Do they increase predation through reducing fitness?
These are all questions QM scientists are working on.
You can find out more about parasites of fish by viewing Flesh-eating Parasites which is one of QM’s Museum Experts videos.
Over the last decade Rob has been investigating the life cycle of QX disease which is a parasitic infection of Sydney Rock Oysters. An outline of the research into the disease, which includes genetic techniques, together with teacher notes and student activities can be found in the online learning resource Disease Detectives.
To learn about other areas of Rob’s research, visit his biography page, Dr. Rob Adlard.