Die-off of sea creatures

Study: Dead sea creatures covered 98% of seafloor last year about 150 miles off California coast

Unprecedented, had been below 1% prior to event — ‘Major’ changes began in spring 201

ENENews,

11 December, 2013

National Geographic, Nov. 22, 2013: [...] “In the 24 years of this study, the past 2 years have been the biggest amounts of this detritus by far,”  said study leader Christine Huffard, a marine biologist at the Monterey Bay Aquarium Research Institute in California. [...] In March 2012, less than one percent of the seafloor beneath Station M [located 145 miles west of the coast of California between Santa Barbara and Monterey] was covered in dead sea salps. By July 1, more than 98 percent of it was covered in the decomposing organisms, according to the study, published this week in the Proceedings of the National Academy of Sciences. [...]  Although climate change is a leading contender for explaining the major increases in 2011 and 2012, Huffard says that these spikes could be part of a longer-term trend that scientists haven’t yet observed. She hopes to continue gathering data from Station M to try and figure it out.

Proceedings of the National Academy of Sciences, Nov. 11, 2013 (emphasis added): [...] Two major peaks in POC [particulate organic carbon] flux occurred over the last 18 mo of the time series [...] The peak POC flux in spring/summer 2011 was the highest recorded over the 24-y time series (Fig. 1D)  [...] The daily presence of detrital aggregates on the sea floor did not exceed 15% coverage over the period from 1990 to 2007. The highest sea-floor coverage by detrital aggregates measured throughout the 24-y time series occurred between March and August 2012, when salp detritus ranged from <1% cover in early March to a high of 98% cover on 1 July (Fig. 1E). This was the only measurable deposition event of salps observed during the entire time series. Following this salp pulse, phytodetrital aggregates combined with some salp detritus formed another major deposition event beginning in late August and peaking in mid-September. This pulse covered up to 61% of the sea floor (Fig. 1E), the largest primarily phytodetrital aggregate peak recorded during the time series. [...] Although environmental variation, such as air temperature and winds, affect the physical dynamics of this upwelling ecosystem, the specific mechanisms behind the changes in food-supply composition and food-web processes corresponding with the peaks in 2011 and 2012 remain unknown. Such increases in food supply appear to change the structure and functioning of deep-sea communities. We already are observing significant changes in populations of benthic fauna [...]

Study’s Supporting Information: Sea Floor Megafaunal Community Change [...] Over an 18-mo period beginning in spring 2011, the densities of epibenthic animals increased by nearly an order-of-magnitude and diversity was considerably lower. Major faunal changes included a substantial reduction in sponge and other sessile animal abundance, and by late 2012 three holothurian species were at the highest densities recorded since mobile megafaunal investigations began in 1989.

See also: "Weird things" happening on California coast: Previously unknown toxic algae blooms proliferating; Unprecedented mass of oxygen-poor water near shore -- TV: Mystery strandings of large squid covered miles and experts baffled... "essentially killing themselves, it’s just really weird" (VIDEO)

And: CBC News: Something very odd is happening in Pacific; Sea creatures acting strangely, species turning up where rarely seen -- Related to Fukushima crisis? -- L.A. Lifeguard: Used to be 2 shark sightings a year, now it's 2 a day (VIDEOS)