The invasive kelp Undaria pinnatifida is has now spread from Los Angeles to San Francisco Bay, despite eradication efforts.

Earlier, the northward spread of this sea weed – which can grow an inch a day and forms dense underwater forests – was believed to have been stopped at Monterey Bay, but this assumption turned out to be wrong when a biologist at the Smithsonian Environmental Research Center happened to notice a six-foot long piece of kelp attached to a boat in a yacht harbor in San Francisco Bay.

“I was walking in San Francisco Marina, and that’s when I saw the kelp attached to a boat,” said Chela Zabin, biologist at the Smithsonian Environmental Research Center in Tiburon, California. “It was six-foot long, and there is nothing here in the bay that gets to that size. I didn’t want to believe what it was, it’s depressing.”

Further investigation showed U. pinnatifida clinging not only to boat hulls in the marina but to docks and pier pilings as well.

U. pinnatifida was discovered in Los Angeles Harbour in 2000 and within a year reports of its presence had arrived from Catalina Island and Monterey Bay. A federal eradication program was put in place, but the funding dried up last year. Since then, volunteer divers have been the only ones combating the kelp.

Five quick facts about Undaria pinnatifida

• Undaria pinnatifida is a fast growing kelp native to the waters of Japan, China and South and North Korea.

• Within its native range it is an appreciate source of food and if you’ve ever tasted miso soup, this is what you were eating. The Japanese name for this species is wakame.

• U. pinnatifida has managed to establish itself in many different regions outside its native range, such as the Atlantic coast of Europe, the Mediterranean Sea, and the Argentinean coast. By attaching itself to vessel hulls it can hitchhike across the globe in search of new suitable habitats. This kelp can also enter ecosystems via imported oysters, and some people deliberately or accidently introduce U. pinnatifida to local ecosystems by cultivating it for cooking purposes.

• When U. pinnatifida spread to ecosystems not used to its presence, it can grow uncontrolled and prevent native kelp species from getting any sunlight. This can disturb the entire ecosystem.

• U. pinnatifida has been nominated to the list “100 worst invasive species in the world”.

The elusive Megamouth shark (Megachasma pelagios) is such an uncommon sight that only 42 confirmed reports of this fish exists since the species was first scientifically described in 1976.

The most recent report, the 42nd one, comes from a group of Philippine fishermen from the city of Donsol who accidently caught a four-metre long specimen while trawling for mackerel.

Mega mouth shark exhibited at the Aburatsubo Marine

Worldwide Fund for Nature project manager Elson Aca examined the fish and identified it as a megamouth shark. The shark weighed an estimated 500 kg and was captured at a depth of 200 metres off the eastern coast of Burias Isle. This wasn’t the shark’s first encounter with fishing gear; it had scars on its face from gill nets.

Soon after being landed at Barangay Dancalan in Donsol, the shark died. Aca entreated the fishermen not to butcher the shark, but the fishermen had a more traditional than scientific approach to caught fish and promptly cooked it with coconut milk, malunggay leaves and chilli to make a Philipine dish known as kinunot.

According to Aca, the the Donsol-Masbate region deserve more attention from conversationalists.

“The presence of two of the world’s three filter feeding sharks warrants special attention for the Donsol-Masbate region”, Aca said. “Whale and megamouth sharks, manta rays, dolphins and other charismatic giants indicate that the region’s ecosystem is still relatively healthy. By protecting megafauna, we help maintain the dynamic balance of our seas, and ensure the entire ecosystem’s resilience and natural productivity.”