“True” wasting disease will be present in individuals that are found in suitable habitat, often in the midst of other affected individuals. All of these symptoms are also associated with ordinary attributes of unhealthy stars and can arise when an individual is stranded too high in the intertidal zone (for example) and simply desiccates. A deflated appearance can precede other morphological signs of the disease. Typically, lesions appear in the ectoderm followed by decay of tissue surrounding the lesions, which can lead to eventual fragmentation of the body and death. Sea star wasting syndrome is a general description of a set of symptoms that are found in sea stars. These sequential photographs of a single individual demonstrate how quickly the disease can progress and the extent of damage that can be done in only three days. The following picture was taken a day later, and the last picture, the day after that.
#Marine aquarium 3 starfish series#
The first photograph in the below series of a sea star with wasting syndrome was taking on June 27 th, 2014 on Guemes Island, Washington. There is no evidence linking the current wasting event to the ongoing disaster at the Fukushima nuclear facility in Japan. Current thinking is that there is likely a pathogen involved, but environmental factors may also play a role, and contributing factors might vary regionally. Molecular sequencing of samples is underway at Cornell University to identify possible causative agents. Thus, there is still much work to be done before this mysterious disease is fully understood. “Densovirus associated with sea-star wasting disease and mass mortality” initially suggested a link between a densovirus (SSaDV) and sea star wasting syndrome (SSWS) but subsequent work revealed that an association between a viral pathogen and SSWS was unlikely in any species other than Pycnopodia helianthoides. Pisaster ochraceus and at least 20 other species of sea stars have been affected by the current SSWS event.
Similar die-offs occurred in the 1970s, 80s, and 90s, but never before at this magnitude and over such a wide geographic area. The disease, called “sea star wasting syndrome” (SSWS) has persisted at low levels in most areas, and continues to kill sea stars. Sea stars along much of the North American Pacific coast experienced a massive die-off in 2013/14 due to a mysterious wasting syndrome. Please direct questions to Melissa Miner, Rani Gaddam, and Melissa Douglas Ecological Consequences and Juvenile Recruitment Photo credits: Melissa Miner (left), Rachael Williams (right).