Marine Mammals Help Mitigate Climate Impacts on Ocean Ecosystems

 

Sea Otter        Photo: Marshal Hedin, Wiki CC

By Ashira Morris, ODP Staff Writer

Kelp forests along the U.S. West Coast are threatened because of an exploding sea urchin population caused by the climate crisis, but in Monterey Bay, sea otters keep the urchin population in check and kelp forests healthy. While many natural underwater systems are out of whack because of climate change, sea others aren’t the only marine mammals helping maintain some equilibrium:

  • In Fiji, reef sharks aren’t just predators — they also patrol coral reefs to keep seaweeds safe from fish that like to eat plants
  • Endangered North Atlantic right whales act as ocean fertilizers, spreading nutrients underwater with their poop
  • In Ecuador’s Gulf of Guayaquil, bottlenose dolphins are the top predator, keeping fish populations in check

Why this Matters: Marine mammals play an important role in global ecosystems as “apex predators, ecosystem engineers and even organic ocean fertilisers,” The Conservation writesMarine mammals worldwide are threatened by changing temperatures, shifting food sources, and acidification. That’s on top of threats they face from human activity like fishing and ship strikes. Allowing marine mammals — and the ecosystems they inhabit — to thrive is part of the push for protecting 30% of the world’s ocean by 2030. These marine protected areas have the added benefit of sequestering carbon as well as protecting wildlife, according to recent research.

Sea Otters Historic Range Includes Estuaries. They Could Return. 

But back to the sea otters: although their place in the kelp forest ecosystem is well-known, California sea otters also used to live in estuaries before the fur trade wiped them out in the 1800s. When conservationists were helping sea otters recover, they only focused on the small remaining pockets where the current population lived, not the massive swaths of coastal estuary that they used to call home. This is one of the many ways that shifting baselines, which skew our sense of “normal” so even as otters are found in fewer places, for example, that depleted state is seen as the baseline.   

However, as Hakai Magazine reports, some scientists want to reintroduce sea otters to California’s estuaries. A study of otters who returned to Elkhorn Slough, an estuary inland from Monterey Bay, found that they helped the native endangered eelgrass return. Just like the sea otters keep sea urchin populations from exploding in other ecosystems, in the estuary, the otters were eating crabs and preventing them from overeating microorganisms that keep algae blooms in check. 

“That was the aha moment,” biologist Brent Hughes, who did the study, told Hakai. “That’s when we realized, okay, these animals really should be in these estuaries.”

Up Next

Ocean Activists Planning to “Flood” the Nation’s Capital Next Week

Ocean Activists Planning to “Flood” the Nation’s Capital Next Week

Hundreds of citizens will fan out across the nation’s capital next week to meet with lawmakers in what’s projected to be the largest ocean lobby effort in US history.  On Tuesday and Wednesday, they will meet with Biden administration officials, federal agencies, and members of Congress for a nonpartisan Ocean Climate Action Hill Day.

Why It Matters:  As the Biden administration and the Congress begin to debate what’s infrastructure and therefore within the American Jobs Plan, the blue economy needs to be front and center in it.

Continue Reading 657 words
Suez Canal Jam Will Take Months to Sort, Many Live Animals Likely Perished on Ships

Suez Canal Jam Will Take Months to Sort, Many Live Animals Likely Perished on Ships

The Evergiven is no longer stuck in the Suez Canal, but world shipping is hardly back to normal. In just six days, the massive container ship held up almost $60 billion in global trade.  Supply chains across the world are delayed and off schedule, and the incident has economists and maritime experts across the globe reevaluating the efficacy of the current shipping economy.  

Why this Matters: The pandemic has rocketed demand for goods (and vaccines) to all-time highs, but bottlenecks at many major ports and slow shipping speed could slow the global economy just as it begins to recover from COVID-19.

Continue Reading 609 words

One Hot Thing: “Seaspiracy” — An Ocean Documentary Is a Top Ten Netflix Film


This explosive new documentary film about the fragile state of the ocean is grabbing attention – it even made the British edition of Vogue Magazine.  In the last week since its release, it has vaulted into the top ten most-streamed films on Netflix.  It has also caused quite a stir — you can read more […]

Continue Reading 147 words

Want the planet in your inbox?

Subscribe to the email that top lawmakers, renowned scientists, and thousands of concerned citizens turn to each morning for the latest environmental news and analysis.