During this wave of mortality, Matassa\u2019s workday started at 6 a.m. on the beach\u2014 \u201cour lab,\u201d as he calls it \u2014 and went on until 7 p.m. or so. He\u2019d talk and text with lifeguards about the animals they found and ferry body parts to the freezers, either at the port or in their homes, where he and his field biologist store samples. Mostly, he performed necropsies \u2014 dissecting dead animals, like this sea lion fetus.<\/p>\n
Matassa was careful and reverent as he cut. He pointed out the fetus\u2019 vibrant red ribcage, the noodly tube of its trachea, and the bean-sized but \u201cpowerful\u201d adrenal gland: all of them \u201cperfect structures,\u201d he observed. When Matassa created OARRA five years ago, it was nobody\u2019s job to study the many dead marine mammals that wash up on LA\u2019s beaches. Matassa, who\u2019d previously worked in animal rehab, hoped that by keeping his eyes on the water, he could help prepare the area\u2019s veterinarians for waves of creatures in urgent need of treatment. But he was especially curious about the animals that would never make it to the hospital in the first place.<\/p>\n
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Matassa\u2019s work station as he performs a necropsy on a sea lion fetus whose mother was suspected of being killed by domoic acid poisoning. Credit: Kate Fishman<\/p>\n
OARRA collects samples of dead animals\u2019 lungs, brains, blubber and more, compiling a biological library of clues for researchers around the country. The data helps scientists learn more about what\u2019s going on in the bodies of marine mammals, in the ocean and on our planet as a whole.<\/p>\n
The blotches of bruising on this fetus\u2019 skull were the only visible sign of what went wrong. Matassa suspected a common culprit \u2014 Pseudo-nitzschia australis, an algae that produces a neurotoxin called domoic acid<\/a>. During algal blooms, domoic acid can accumulate in shellfish, sardines and anchovies, shutting down some fisheries and spelling tragedy for the sea lions and dolphins that eat those fish. Mammals that consume too much of the toxin suffer seizures, heart attacks and brain damage. This year\u2019s neurotoxin outbreak was particularly devastating, and started several months earlier than Matassa had come to expect.<\/p>\n Matassa filled a couple dozen vials with the sea lion\u2019s innards. Cross-referencing the fetus\u2019 samples with those collected from its mother\u2019s body will help illuminate how and why the neurotoxin is so deadly \u2014 especially for pregnant sea lions<\/a>.<\/p>\n \u201cEvery dead animal has a story to tell,\u201d Matassa said, \u201cand we need to tell it.\u201d<\/p>\n DOMOIC ACID TOXICOSIS<\/strong> isn\u2019t a new phenomenon. Scientists at The Marine Mammal Center in Sausalito, California, first documented the condition in 1998, but over the past four years, outbreaks have become increasingly common in California. \u201cWe have been grappling as a community with this sense that, like wildfires, these things are kind of year-round now,\u201d said Clarissa Anderson, an oceanographer at University of California San Diego\u2019s Scripps Institute and director of the Southern California Coastal Ocean Observing System. Anderson\u2019s research shows that the upwelling of nutrients from deeper, colder waters seems to drive the recent algal blooms. She developed the CA-Harmful Algae Risk Mapping system<\/a> to track and predict them.<\/p>\n \u201cA lot of the problems that animals have as individuals are related to human activities.\u201d<\/p>\n<\/blockquote>\n The data that Matassa and his team collect is crucial to helping researchers understand the big picture. This spring, Anderson and her colleagues held weekly calls with stranding teams like OARRA to compare notes and plan for data collection \u2014 lines of communication she believes will be critical in years to come. The data that the stranding coordinators record reveals where the toxin shows up in a carcass and how the animal died, and their observations on the beaches \u2014 both at baseline and during an outbreak \u2014 can help answer her many remaining questions: Why do some years see an outbreak of domoic acid toxicosis in mammals while others don\u2019t, even when the algae is present in the water column? How does runoff from the land impact phytoplankton and marine mammals? And how are rising global greenhouse gas emissions altering the water\u2019s chemistry?<\/p>\n \u201cA lot of the problems that animals have as individuals are related to human activities,\u201d said Cara Field, the director of conservation medicine at The Marine Mammal Center.<\/p>\n Caring for and healing live animals makes for more inspirational stories than working with \u201cdead things,\u201d as Matassa puts it. But by studying these dead things, he\u2019s banking knowledge that may prove to be of great value years from now. A diligent necropsy can take several hours to complete, even with several people helping. Everyone clusters around the animal \u2014 often in the bed of Matassa\u2019s truck \u2014 to make cuts, collect samples, take pictures and record notes. It\u2019s an act of faith in what science can learn about these animals\u2019 health \u2014 and perhaps our health as well.<\/p>\n Back at the lab, Matassa labeled and filed each sample, in a process that\u2019s ingrained in his muscle memory. Like the urine, fecal and stomach content samples he collected and shipped from 122 other marine animals so far this year, these will be sent to pathologists and to the Northwest Fisheries Science Center in Seattle. He looked over the remains of his morning\u2019s work with weary, frank optimism. \u201cThere\u2019s nothing hidden inside that animal anymore,\u201d he said.<\/p>\n Spread the word. News organizations can pick-up\u00a0quality news, essays\u00a0and feature stories for free.<\/p>\n Republish This Story<\/p>\n\n
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