Quantcast
Climate
Deep-sea corals may not be flashy, but they deserve a second look. Oceana

Ignoring Deep-Sea Corals Is Risky for the Oceans, and for Us

By Nathan Johnson

The deep sea might be cold and dark, but it's not barren. Down here, an incredible diversity of corals shelters young fish like grouper, snapper and rockfish. Sharks, rays and other species live and feed here their whole lives.

Brightly colored coral gardens, far beyond the reach of the sun's rays, don't just nurture deep-sea life. They also help advance medical research and understand climate change.


Crucial though they are, such deep-dwelling corals are rarely glimpsed and easy to overlook. They don't get much notice from us on the surface. Here are five reasons they are worthy of respect—and attention.

A peachy deep-sea coral in the Alboran Sea.Oceana

1. Deep Doesn't Mean Deserted

Deep corals are strikingly similar to their shallow, tropical relatives, but get much less attention. While they don't form typical coral reefs, aggregations of these species can transform the rocky seafloor into a neon garden, 10,000 feet down.

These "gardens" are crucial feeding grounds in a part of the ocean where food can be scarce. They also act as nurseries for juvenile fish, crabs and shrimp, and provide a hard surface where sea stars and crustaceans can settle.

2. If You Love Seafood, You Need Deep Corals

Shrimp, crabs, grouper, rockfish and snapper that rely on deep corals support the diets and jobs of hundreds of thousands of people. Eighty five percent of economically-important fish in Alaska's Aleutian Islands use deep-sea coral habitat at some point in their life cycle. And a 2010 article in the journal Marine Resource Economics concluded that these corals are essential habitat for redfish in Norway.

3. They're Catalysts for Scientific and Medical Advances

Deep-sea corals provide unique opportunities for medical and climate research. Bamboo corals, which have been found deeper than 1,000 meters, have skeletons like bone. By better understanding these corals, scientists may develop more effective bone-grafting techniques.

Deep corals can also live for hundreds or thousands of years. As they grow, their skeletons form additional bands or layers, like tree rings, that reflect the chemical environment around them. The skeletons of long-lived specimens give researchers a window into the ways that ocean conditions, like temperature and nutrient availability, have changed over time.

On Oceana's expedition to Malta in June 2016, expedition leader Ricardo Aguilar watches deep-sea coral on a feed from a diving robot. Oceana / Carlos Minguell

4. Living Deep Won't Save Corals From Human Harms

In some places, these deep gardens are dying.

Commercial fishing is one major threat. Bottom trawling ships drag large, weighted nets across the seafloor that indiscriminately catch anything in their way. Roller-frame trawls have heavy cylinders attached to the bottom of the net, which can bulldoze entire ecosystems in just a few hours.

Offshore oil drilling can also harm fragile corals. Oil spills hit deep-sea corals in much the same way they impact shallow, tropical reefs. In the Gulf of Mexico, a 2012 study showed evidence of tissue damage, stress, and coral death from samples collected 290 to 2,600 meters below the surface, likely from the Deepwater Horizon oil spill.

Climate change adds additional challenges. Unlike their tropical cousins, deep corals don't have symbiotic algae living in their tissue, so they don't bleach and die when the water gets too hot. But they are vulnerable to changes in pH, which are also brought on by climate change.

As more carbon dioxide dissolves into the oceans, seawater becomes more acidic. Both deep and shallow corals have a harder time building their skeletons as a result. Since deep-sea corals grow slowly, it can take hundreds of years for them to recover.

5. Deep-Sea Corals Get Overlooked in Favor of Flashier Reefs

If deep-sea corals disappear, so will the fish, crabs, and sharks that rely on them. In a series of expeditions, Oceana and its partners have explored these lesser-known corals and their habitats in the Philippines, Canada, Europe and U.S. Pacific. But little has been done to protect these deep-sea corals. In 2015, less than 1 percent of total U.S. giving from private foundations was for ocean-related grants. More than half of the $17.6 million that private foundations gave for coral work that year went to tropical corals.

A fire worm (center) undulates over colorful deep coral in the Atlantic. Oceana / Juan Carlos Calvin

Deep corals might not offer the tropical-vacation allure of reefs in the Caribbean or Asia, but they're just as vital.

Show Comments ()

EcoWatch Daily Newsletter

Sponsored
Popular
Kodachrome25 / Getty Images

Roof-to-Garden: How to Irrigate with Rainwater

By Brian Barth

The average American household uses about 320 gallons of water per day, a third for irrigation and other outdoor uses. Collecting the water flowing down your downspouts in rainstorms so you can use it to irrigate in dry periods is often touted as a simple way to cut back. But setting up a functional rainwater irrigation system—beyond the ubiquitous 55-gallon barrels under the downspout, which won't irrigate much more than a flower bed or two—is a fairly complicated DIY project.

Keep reading... Show less
Health
A family wears face masks as they walk through the smoke filled streets after the Thomas wildfire swept through Ventura, California on Dec. 6, 2017. MARK RALSTON / AFP / Getty Images

How to Protect Your Children From Wildfire Smoke

By Cecilia Sierra-Heredia

We're very careful about what our kids eat, but what about the air they breathe?

Keep reading... Show less
Health
Hero Images / Getty Images

Study: Children Have Better Nutrition When They Live Near Forests

Spending time in nature is known to boost mental and emotional health. Now, a new global study has found that children in 27 developing nations tend to have more diverse diets and better nutrition when they live near forests.

The paper, published Wednesday in Science Advances, provides evidence that forest conservation can be an important tool in promoting better nutrition in developing countries, rather than clear-cutting forests for more farmland.

Keep reading... Show less
Health
Navy torpedo bomber spraying DDT just above the trees in Goldendale, WA in 1962. USDA Forest Service

Maternal DDT Exposure Linked to Increased Autism Risk

A study published in the American Journal of Psychiatry Thursday found that mothers exposed to the banned pesticide DDT were nearly one-third more likely to have children who developed autism, Environmental Health News reported.

Keep reading... Show less
Sponsored
GMO
Significant cupping of leaves from dicamba drift on non-Xtend soybeans planted next to Xtend beans in research plots at the Ashland Bottoms farm near Manhattan, KS. Dallas Peterson, K-State Research and Extension / CC BY 2.0

Top Seed Companies Urge EPA to Limit Dicamba

Two of the nation's largest independent seed sellers, Beck's Hybrids and Stine Seed, are urging the U.S. Environmental Protection Agency (EPA) to place limits on the spraying of the drift-prone pesticide dicamba, Reuters reported.

This could potentially hurt Monsanto, which along with DowDupont and BASF SE, makes dicamba formulations to use on Monsanto's Xtend seeds that are genetically engineered to resist applications of the weedkiller. Beck's Hybrids and Stine Seed, as well as other companies, sell those seeds.

Keep reading... Show less
Food
Baby son in high chair feeding father. Getty Images

Baby Food Tests Find 68 Percent Contain 'Worrisome' Levels of Heavy Metals

Testing published by Consumer Reports (CR) Thursday found "concerning levels" of toxic metals in popular U.S. baby and toddler food.

The consumer advocacy group tested 50 nationally-distributed, packaged foods designed for toddlers and babies for mercury, cadmium, arsenic and lead.

Keep reading... Show less
Sponsored
Popular
Interior Secretary Ryan Zinke talks to journalists outside the White House West Wing before attending a Trump cabinet meeting on Aug. 16. Chip Somodevilla / Getty Images

Zinke Announces Plan to Fight Wildfires With More Logging

The Trump administration announced a new plan Thursday to fight ongoing wildfires with more logging, and with no mention of additional funding or climate change.

Keep reading... Show less
Energy
Wangan and Jagalingou cultural leader Adrian Burragubba visits Doongmabulla Springs in Australia. The Wangan and Jagalingou are fighting a proposed coal mine that would likely destroy the springs, which are sacred to the Indigenous Australian group. Wangan and Jagalingou

Indigenous Australians Take Fight Against Giant Coal Mine to the United Nations

By Noni Austin

For tens of thousands of years, the Wangan and Jagalingou people have lived in the flat arid lands of central Queensland, Australia. But now they are fighting for their very existence. Earlier this month, they took their fight to the United Nations after years of Australia's failure to protect their fundamental human rights.

Keep reading... Show less
Sponsored

mail-copy

The best of EcoWatch, right in your inbox. Sign up for our email newsletter!