coral reefs tagged posts

Coastal Lights Damage Coral Reefs

For the history of life on Earth, organisms have relied on the light of the sun, moon, and stars to navigate their way and schedule their lives. While the onset of electric lighting in the late 19th century may have been a boon to humans, it has wreaked havoc on the natural world. Among the more notorious impacts of artificial light at night (ALAN), light pollution lures migrating birds to cities with devastating consequences, contributes to the alarming decline in insect populations, and convinces sea turtle hatchlings to amble away from the water instead of towards it.

Now, a new study from the University of Plymouth adds another dismal finding about how ALAN is affecting the creatures with whom we share the planet: Light pollution from coastal cities can trick coral reefs into s...

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Scientists Race to Restore Florida’s Nearly Extinct Reefs

On a few nights each August, just days after the full moon, Hanna Koch will be keeping watch at the Mote Marine Laboratory’s outpost on Florida’s Summerland Key, peering into tubs of water at the tentacle-ringed mouths of brilliant green, yellow, and purple corals. Close to midnight, staghorn, elkhorn, brain, and star corals will release tens of thousands of tiny glowing orbs into the water, and Koch will have her only chances of the year to create new generations of the species.

Each orb, or gamete bundle, holds millions of sperm and multiple eggs. In the wild, the bundles would separate, find different partners, and combine to create larvae that would swim and ride currents to settle on reefs...

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How Jordan saved its coral reefs through a simple idea

Jordan is a country known for its ancient rock-cut city of Petra, and for the salt lake called Dead Sea that lies to its west. But over the past decade, it also became a forerunner in coral reef preservation through an ingenious idea. Coral reefs are scattered along the Gulf of Aqaba, a popular area for tourists – specifically scuba divers – who love to explore the area’s reefs and marine life. The region is home to 127 species of Aqaba’s delicate corals, some of which are 6,000 years old, according to an April 2018 report in the National Geographic.

But with growing urban development along the coast of the city, some changes had to be made. The nation wanted to meet tourist demand, but not at the cost of destroying the area’s marine life...

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East Africa reefs could die out in 50 years

Scuba divers swim past fish along a coral reef off the west coast of Zanzibar island, Tanzania

Coral reefs in the western Indian Ocean are at risk of extinction by 2070 due to warming temperatures and overfishing, according to a new study.

A roughly 12,000 sq km expanse of coral reefs stretching down the eastern coastline of Africa and around Madagascar is facing ecosystem collapse, threatening a range of species and the livelihoods of over a million people who work in the fishing and tourism industries. These reefs make up around 5% of the planet’s total coral reef area.

“When an ecosystem collapses, we might still see individual fish or corals but the whole system is no longer effective in supporting either marine biodiversity or communities who are dependent on it,” said David Obura, a Kenyan marine ecologist at CORDIO East Africa and lead author of the study.

Published...

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Can Red Sea coral show us how to save the world’s reefs?

Feathery orange moss, bouquets of tightly bound lime green and mustard yellow buds, gently swaying blood red branches, and huge pebbles adding a shock of blue and purple – to the uninitiated, this dazzling display might resemble an underwater garden, albeit an improbably colourful one.

And in a way it is. Except when you get up close, really close, and you see the thousands of tiny creatures, often no bigger than half an inch wide, packed tightly together in colonies to create this ethereal Red Sea landscape. We are of course talking about coral polyps, the soft-bodied organisms that together can form reefs the size of islands.

They only cover a tiny area of the earth – less than one per cent – but they are the vital building blocks of a healthy marine ecosystem...

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Half of Earth’s coral reefs have been lost since 1950

Great Barrier Reef

Coral reefs provide an irreplaceable ecosystem for marine life, protect coastlines and sustain livelihoods of communities around the globe — so you can understand why scientists are concerned about the worldwide phenomenon of coral reef erosion. A new study indicates the pace of reef destruction is faster than previously thought.

Half of the Earth’s coral reefs have died out in the last 70 years, according to a study published in the One Earth journal. Researchers note that fishes caught per capita (or rather, per “unit of effort”) have declined 60% since 1950 and that coral reefs are half as able to provide ecological services as they were in the 1950s. The result is less biodiversity in the world’s reefs.

“Coral reefs worldwide are facing impacts from climate change, overfishing,...

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Reforestation could help save coral reefs from catastrophe

Increasing reforestation efforts in coastal regions could substantially reduce the amount of sediment run-off reaching coral reefs and improve their resilience, a University of Queensland-led study has found. The study analysed more than 5,500 coastal areas from around the world and found that nearly 85 per cent of them leached sediment to coral reefs, the second most serious threat facing the world’s reefs behind climate change. Dr Andrés Suárez-Castro from UQ’s Centre for Biodiversity and Conservation Science said it was important to address the issue of sediment runoff if efforts to reduce the human impact on reefs were to be successful.

“Increased sedimentation can cause aquatic ecosystems to be more sensitive to heat stress, which decreases the resilience of corals to pressures ...

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Scientists Create the First Complete Map of the World’s Coral Reefs

Ailinginae Atoll in the Marshall Islands. (photo by Greg Asner; courtesy of Allen Coral Atlas)

Coral reefs are sometimes referred to as “the rainforests of the seas” — they are one of the most biodiverse ecosystems on the planet. Although they cover just one percent of the ocean floor, these mesmerizing, scaly habitats support an estimated 25 percent of all marine life. They are also highly endangered: the climate crisis, coastal development, ocean acidification, and destructive overfishing are a few of the many factors contributing to their alarming decline. By some estimates, nearly all remaining reefs will be at risk by 2050.

Scientists have now completed the first comprehensive, continually-updated map of the world’s shallow coral reefs, a critical tool for their preservation. Using 2...

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Groundwater Runoff Changing Metabolism of Coral Reef Ecosystems

Maunalua Bay in Hawaii, where CSUN marine biologist Nyssa Silbiger and her colleagues found that submarine groundwater discharge is changing the metabolism of coral reefs ecosystems. Photo by Doug Harper.

Submarine groundwater discharge — the flow of fresh water from land through the coastal seafloor into the ocean — is changing the metabolism of coral reef ecosystems, according to California State University, Northridge marine biologist Nyssa Silbiger, which can affect coastal economies around the world.

The findings by Silbiger and her fellow researchers, Megan Donahue with the Hawaii Institute of Marine Biology and Katie Lubarsky with the Scripps Institution of Oceanography, have implications for understanding human impacts on marine ecosystems, as well as informing the decisions of policy makers as they consider coastal development or anticipate the impacts of sea-level rise.

“If we can understand how actions and decisions made miles away from the ocean affect marine ecosyste...

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Is Key Gene System Discovery Suffocating Corals’ Last Gasp?

A unique stress experiment aligned deoxygenation stress to the natural night-day cycle of common reef-building corals from The Great Barrier Reef. Credit: Morgan Bennett-Smith

Ocean deoxygenation is now being recognized as major threat to future global coral reef survival.

Oxygen is life, in or out of the water, raising concerns that declining ocean oxygen stores are adding an additional environmental stress to already highly vulnerable coral reef ecosystems. While the twin effects of ocean warming and acidification are well studied, until now there has been limited understanding of how the growing threat of ocean deoxygenation may impact the ability of corals to function and ultimately form reefs.

A unique deoxygenation-reoxygenation stress experiment has given researchers from the University of Technology Sydney (UTS), University of Konstanz and University of Copenhagen insight into how corals manage deoxygenation stress and the key genes that likely dr...

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