Pacific Rocky Intertidal Monitoring: Trends and Synthesis
Sea Star Wasting Syndrome Updates
Click here for the Sea Star Wasting Syndrome Map (Updated Nov 26, 2013)
Click here for Articles, Publications, and more information (Updated Dec 3, 2013)
Please continue to send in tracking logs after spending time diving or in the intertidal. We are constantly updating our website with the latest reports, and will update the map on a regular basis. Please remember to fill out a log even if you search and only find healthy sea stars, or no sea stars! This information is just as valuable as observations of diseased individuals.
We continue to receive many reports of sea star wasting along the West Coast of the United States. To date, our most northern report comes from the Anchorage Museum in Alaska. There, mottled sea stars (Evasterias spp.) in the aquarium showed signs of wasting. These individuals were collected from Whittier, AK and Seward, AK, though it is unknown at what point they became sick.
During the last couple weeks, the UC Santa Cruz group sampled a number of our Long-Term Monitoring sites in central California. Most sites had at least a few affected individuals of the ochre star (Pisaster ochraceus). We were able to confirm presence of wasting in San Luis Obispo County, though diseased individuals were less prevalent overall than what we have observed in the Santa Cruz County area. Intertidal Long-Term Monitoring plots at Hopkins Marine Station were recently sampled with only approximately 2 ½ weeks in between surveys. When sampled on October 18, there were no signs of disease, and the abundances in the plots were within fluctuations documented since we established monitoring plots in 1999. We resampled the plots on Nov 5 and observed disease in about half of the ochre stars (Pisaster ochraceus). Overall abundance had dropped quite a bit, lower than recorded anytime during the previous 14 years of monitoring. We also received reports that in the subtidal off Hopkins Marine Station, sunflower stars (Pycnopodia helianthoides) had been abundant several weeks ago, but during a recent class dive trip, none were observed (Raimondi pers. com.). Observations such as these emphasize how quickly sea stars can go from appearing healthy to dying from whatever is causing this wasting event.
Currently, our most southern report along the West Coast comes from Laguna Beach in Orange County, CA. Based on our collected observations to date, it seems that while wasting syndrome is present in southern California, the percent of affected individuals is much lower than what has been documented farther north.
The cause of the wasting event is still unknown. Researchers from universities including Cornell, University of Rhode Island, Brown, and Roger Williams continue to work to determine the pathogen.
Signs of sea star wasting disease have been popping up on both the East and West Coasts of the United States, as well as reports globally. On the West Coast, sea star wasting has been observed as far north as Southeast Alaska, and as far south as Orange County, California. To date, we have received reports of at least 10 species of sea stars showing signs of infection. Reports of sea star disease and mortality on the East Coast began showing up in articles during July of this year. On the West Coast, sea star wasting was first documented in June (although see Bates et al. for 2008 event), and by September observations were much more widespread, with accounts of diseased, dying and dead sea stars from numerous locations along the West Coast.
The first evidence of a possible wasting event came in June when Long-Term Monitoring sites in Washington (monitored by Olympic National Park) recorded diseased stars with percent affected rates between 3-26%. Symptoms of wasting disease in a few Pisaster ochraceus were also noted in August at an intertidal Biodiversity site in Southeast Alaska. Articles from British Columbia, Canada report sightings of dozens of dead sea stars (notably Pycnopodia helianthoides) beginning in September, not far from Vancouver. One report from Vashon Island in Puget Sound indicates signs of wasting in Pycnopodia helianthoides from March of this year. This is the earliest account we have on the West Coast for 2013. From Friday Harbor Laboratories, we have received a report of diseased Henricia spp. and Evasterias troschelii at the southern tip of San Juan Island. In Oregon, we saw no obvious signs of wasting sea stars during Long-Term Monitoring surveys in May-August. Word-of-mouth accounts indicate that there may be wasting occurring at some sites in Oregon, and we hope to have more information from that section of coast soon.
In California, accounts of wasting in sea stars range from just north of Bodega Bay down to Orange County. In the Bodega Bay area there have been reports of wasting in sea stars both subtidally and intertidally. Researchers from UC Davis Bodega Marine Laboratory have observed wasting in Pisaster ochraceus in the intertidal at Schoolhouse Rock, just north of Bodega Bay, since spring 2013. In San Francisco, at the Gulf of the Farallones National Marine Sanctuary office building, Pisaster ochraceus in the office aquarium began “falling apart” in early October. Numerous observations of wasting in sea stars have recently been made in the region between San Francisco south to Big Sur. Accounts have come by way of Long-Term Monitoring from MARINe, LiMPETS, and PISCO, and from researchers from multiple institutions such as Long Marine Lab, Monterey Bay Aquarium Research Institute (MBARI), Monterey Bay Aquarium, and Moss Landing Marine Laboratories, as well as from recreational divers. In central California, species affected thus far include Pisaster ochraceus, Pisaster brevispinus, Pisaster giganteus, Dermasterias imbricata, Asterina (Patiria) miniata, Orthasterias koehleri, Pycnopodia helianthoides, and Henricia spp.
Interestingly, observations of wasting are patchy. For example, wasting sea stars have been seen subtidally off of Hopkins Marine Station in Monterey, but extensive searching in the intertidal nearby turned up only healthy looking individuals and abundances are within the natural fluctuation observed in Long-Term Monitoring plots at that site. Multiple other sites, however, have shown drastic declines in abundance below the fluctuation typically observed at those sites. In San Luis Obispo County, reports of wasting come from Corallina Cove in Montaña de Oro State Park. There, a CA State Parks scientist received information that sea stars were washing up on the beach; it has not yet been confirmed that this could be attributed to wasting.
The cause of this wasting event is still unknown, though researchers from various universities including Cornell, University of Rhode Island, Brown, and Roger Williams are currently working to identify the pathogen.
For more information about Sea Star Wasting Disease, please see the links below:
Sea stars stricken by mysterious wasting disease (Nov 26, 2013)
Sea Star Wasting Disease Hists the West Coast (Nov 21, 2013)
What's wiping out the starfish in California (Nov 12, 2013)
Sea Star Wasting Syndrome Reaches Santa Barbara County (Nov 7, 2013)
Starfish wasting disease baffles US scientists (Nov 5, 2013)
Wasting disease devastating starfish along Sonoma Coast (Nov 2, 2013)
Marine Scientists Investigate Massive Sea Star Die-Off (October 10, 2013)
Starfish Deaths Alarm Vancouver Aquarium (October 7, 2013)
Dead starfish in Vancouver waters puzzle scientists (September 12, 2013)
Sunflower star wasting video (courtesy Vancouver Aquarium)
Sea Star Wasting Disease (Seadoc Society)