You might have heard about urban legends that involved the Loch Ness Monster but have you ever heard of the tale of the Five Armed Goo Monster? This monster lives in the water but will occasionally lurk on the coasts of beaches for its prey. In its earlier stages, it is a silent predator that is able to execute with ease and efficiency. Rumour has it that this so called Five Armed Goo Monster is none other than sea stars. Who would have guessed that these beautiful creatures would be called monsters? It turns out that sea stars have become victims of a deadly virus that causes them to turn into these goo monsters. This virus has been spreading like wildfire since 2013 and affected many species including, Pisaster ochraceus and Pycnopodia helianthoides. The virus causes the sea star to start losing their limbs and eventually white goo begins to ooze from their body. Sea star wasting syndrome is what the sea stars are experiencing and it has had an immense impact on their populations. The sea star populations are at an all time low and some species have taken advantage of their absence. Many species have become established on the rocky reefs. Can you imagine what the coast will be like without these majestic organisms? The ultimate question that you might have is what lead to the success of the virus. This is a question that needs to be answered.
To investigate the potential factors that could have escalated the disease outbreak, our class decided to look at temperature and salinity effects on Evasterias troschelii. I examined the specific behaviours of sea stars, such as feeding and flipping over rate, when exposed to these different conditions. Research has indicated that high temperature facilitates disease outbreaks of viruses. The warmer temperature provides the virus with a favourable environment to allow for spreading of the disease. Furthermore, low salinity introduces stress on the sea star which, in turn, compromises immune function. This picture represents one of the behaviours that I observed while in lab. This sea star sure was hungry as it can be seen devouring the mussel.
Which factor was responsible for fueling the sea star syndrome? From the experiments that I conducted, the sea stars were not strongly influenced by temperature or salinity. This question is a lot more complicated than I would have thought. Could there be other abiotic factors that might influence them turning into piles of goo? Could there be an interaction of multiple factors that determine the fate of the sea star? With these questions in mind, the tale of the Five Armed Goo Monster continues until next time.
Here is a video on sea star wasting syndrome: https://www.youtube.com/watch?v=VPSFdjvES_Y
For more information on the impacts of the disease on the functioning of seas stars visit: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0133053