Coral reef flattening leads to drastic decline in species

September 7, 2015, Newcastle University
Close up of polyps are arrayed on a coral, waving their tentacles. There can be thousands of polyps on a single coral branch. Credit: Wikipedia

Species risk being lost if the ongoing degradation of coral reefs in the Caribbean goes beyond a certain critical point, scientists say.

In a study published today in the Journal of Animal Ecology, an international team of led by Newcastle University has for the first time identified a threshold for the complexity of coral reef systems in the Caribbean below which the number of declines.

A more reef structure should be able to sustain a more diverse community of species and bigger populations. However, bleaching, damage from hurricanes, changes in nutrients and the effects of fishing and other human activity have led to a degradation, or flattening, of coral structures.

Using a variety of habitat measures and looking at the full range of reef species, the research team showed similar trends in three widely-separated areas in the Caribbean: Bonaire, Puerto Rico and St Vincent & the Grenadines. They discovered that total species richness was greatest in areas where reef complexity was high, and declined considerably in reefs where structures had been degraded.

Although the importance of reef complexity for fishes is known, until now the extent to which flattening affects the total reef ecosystem at large scale has been scarcely known.

Nick Polunin, Professor of Marine Environmental Science at Newcastle University, said: "Complex such as those in the Caribbean are among the most species-diverse habitats on the planet, and this research shows that the architecture of these systems plays a crucial role in maintaining all those species.

"These findings help us better understand the effect that changes in reef shape, height and complexity have had and are having on total species richness, when corals are not replaced naturally and the reef gets broken down by erosion.

"If reefs are degraded to the point where their complexity falls below a certain critical level, this could mean some species disappearing entirely from the Caribbean reef system, and substantial declines in all reef species, in particular corals and fishes. This will have a profound impact on the variety of species present and undermine the resilience of the entire Caribbean reef ecosystem, as well as threatening -based fisheries."

Explore further: Endangered corals smothered by sponges on overfished Caribbean reefs

More information: "Reef flattening effects on total richness and species responses in the Caribbean." Journal of Animal Ecology. doi: 10.1111/1365-2656.12429

Related Stories

Specialized species critical for reefs

September 15, 2014

One of Australia's leading coral reef ecologists fears that reef biodiversity may not provide the level of insurance for ecosystem survival that we once thought.

Sharks more abundant on healthy coral reefs

September 10, 2014

Sharks in no-fishing zones in the Great Barrier Reef (GBR) Marine Park are more abundant when the coral is healthy, according to a study published September 10, 2014 in the open-access journal PLOS ONE by Mario Espinoza from ...

A fish too deep for science

July 17, 2015

Drs. Carole Baldwin and Ross Robertson from the Smithsonian Institution discovered a new small goby fish that differs from its relatives not only in its size and colors, but also in the depth of its habitat (70-80 m) in the ...

Recommended for you

In colliding galaxies, a pipsqueak shines bright

February 20, 2019

In the nearby Whirlpool galaxy and its companion galaxy, M51b, two supermassive black holes heat up and devour surrounding material. These two monsters should be the most luminous X-ray sources in sight, but a new study using ...

When does one of the central ideas in economics work?

February 20, 2019

The concept of equilibrium is one of the most central ideas in economics. It is one of the core assumptions in the vast majority of economic models, including models used by policymakers on issues ranging from monetary policy ...

Research reveals why the zebra got its stripes

February 20, 2019

Why do zebras have stripes? A study published in PLOS ONE today takes us another step closer to answering this puzzling question and to understanding how stripes actually work.

Correlated nucleons may solve 35-year-old mystery

February 20, 2019

A careful re-analysis of data taken at the Department of Energy's Thomas Jefferson National Accelerator Facility has revealed a possible link between correlated protons and neutrons in the nucleus and a 35-year-old mystery. ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.