sail-world.com
 
 
News Home Cruising Photo Gallery Video Gallery
Sail-World.com : Weed-eating fish beneficial to jobs, livelihoods and ecotourism?
Weed-eating fish beneficial to jobs, livelihoods and ecotourism?

'Coral reefs sustain more biodiversity than any other ecosystem in the world’s oceans.'    ARC Centre of Excellence Coral Reef Studies ©    Click Here to view large photo

Having a diverse supply of weed-eating fish on the world’s coral reefs can be beneficial to jobs, livelihoods, and the ecotourism industries, marine researchers say. Despite their small size, relative to the sharks, whales, and turtles that often get more attention, herbivorous fish play a vital role in maintaining the health of coral reefs, which support the livelihoods of 500 million people worldwide, say researchers from the ARC Centre of Excellence for Coral Reef Studies at James Cook University, and the Australian Institute of Marine Science.

'Herbivorous fishes protect coral reefs by limiting the growth of algae, or seaweed,' says Loïc Thibaut, lead researcher of a new study that has been published in the journal Ecology. 'Seaweeds grow rapidly and compete with corals for space. If left unchecked, they can smother the corals and take over the reefs. This shift, once it happens, is extremely difficult to reverse.'

The study shows that having high biodiversity of herbivorous fishes provides strong 'insurance' for coral reefs. A diverse set of herbivores ensures that seaweeds are kept under control, because when some species take a hit and decline, others increase to fill the gap. This makes seaweed control more stable over time, something researchers call the 'portfolio effect'.

'It’s like having a diverse stock portfolio – you wouldn’t put all your money into one particular stock, because if that company goes down, so will your life savings,' says Professor Sean Connolly, a Chief Investigator at the Centre. 'A very similar principle works in ecosystems.'

An example of the disastrous effects of having only one herbivore as ‘gatekeeper’ is the extensive coral loss in the Caribbean in the 1980s.

'In the 80s, overfishing left a species of sea urchin as the only animal controlling seaweed growth on Caribbean reefs. When a disease broke out, the sea urchin population collapsed - and there was nothing to keep the weeds in check. This was followed by an explosion of seaweeds, which smothered the coral and hit tourism pretty hard,' says Prof. Connolly.

The study, which applied cutting-edge analyses designed by the JCU researchers to and data from the Australian Institute of Marine Science’s 15-years of surveys across the Great Barrier Reef, found that protection was provided by having a diversity of fish that perform a similar function – chomping down seaweed – because different fishes respond differently to different pressures.

Healthy coral reef community with high numbers of herbivorous fish on Tiahura Reef -  ARC Centre of Excellence Coral Reef Studies ©   Click Here to view large photo


'There are three main groups of herbivorous fishes: territorial grazers that bite at the algae and are site-attached and actively defend a small patch of reef, roving grazers that feed in the same way but move around the reefs, and scrapers who range widely and feed by biting the algae back to the limestone surface of the reef, making clear patches where corals can establish. All are critically important,' says study co-author Dr. Hugh Sweatman, a Senior Research Scientist at the Australian Institute of Marine Science.

'These groups all play a similar role in keeping weeds in check, but each type responds differently to environmental fluctuations.'

'In this research, we measured how strong the ‘portfolio effect’ was in different reef locations. We found that high biodiversity makes seaweed control twice as stable as it would be if we relied on one super-abundant species, like the sea urchin in the Caribbean,' says Prof. Connolly.

'Biodiversity reduces the risk that environmental fluctuations will push overall herbivory below the threshold that might trigger a regime shift towards seaweed-dominated reefs.'

The finding highlights the importance of maintaining biodiversity in the coral ecosystem, the researchers say.

'The more diversity you have, the lower the risk that all the fish that play a particular role on the reef – like controlling seaweeds – will crash at the same time. This is greatly beneficial for the health of any type of ecosystem. And it is also beneficial to the people whose jobs and livelihoods depend on that system,' says Mr. Thibaut.

The paper 'Diversity and stability of herbivorous fishes on coral reefs' by Loïc M. Thibaut, Sean R. Connolly and Hugh P.A. Sweatman is published in the latest issue of Ecology.

ARC Centre of Excellence for Coral Reef Studies website


by ARC Centre of Excellence for Coral Reef Studies

  

Click on the FB Like link to post this story to your FB wall

http://www.sail-world.com/index.cfm?nid=97004

8:33 PM Tue 8 May 2012GMT


Click here for printer friendly version
Click here to send us feedback or comments about this story.







News - USA and the World



































































CMRC Summer Invitational Series - Doubleheader events start tomorrow
BIC Techno 293 Worlds 2014 - Day 3
Sailing through STEM Night at California YC
Six Metre European Championship - High temps and little wind on day 3
Women’s Match Race Golfe du Morbihan - Light wind opener in Vannes
International Moth Worlds: Rashley ahead as Aussies close in
Brewin Dolphin Commodores' Cup - Unsatisfactory conditions on day 4
ISAF Youth Match Racing Worlds - American unbeatable on day 1
RS Feva World Championships - All set at Yacht Club de Carnac
ISAF Rolex World Sailor of the Year Awards - Nominations now open
BIC Techno 293 Worlds - Steady winds on day 2 + Video
29er North American Open Championship - Qualifying series wraps up
Opening ceremony O'pen Bic World Cup, Travemunde Week, Germany
Six Metre Europeans - Wind fails to make an appearance on day 2
Edgartown Race Weekend - Let the sailing (and good times) begin
ISAF Youth Match Racing World Championship - Action commences July 23
International Moth Worlds - Mothballed on day 4 + Video
Brewin Dolphin Commodores' Cup - Ireland remains out front
Spirits high as Team Alvimedica completes Transatlantic crossing
Gladwell's Line: A change of direction needed in the America's Cup *Feature
29er North American Championship - Day 1 in Kingston   
Red Bull 49erFX: First look at the Olympic sailing venue at Rio   
Fuerteventura Kiteboarding Grand Slam - Classic conditions on day 3   
NYYC Race Week Part II images by Rolex/Daniel Forster   
Drowning or electric shock? What you need to know to help save a life   
BIC Techno 293 Worlds 2014 - Day 1   
Six Metre European Championship - Blazing sunshine on opening day   
National Sailing Hall of Fame to present Lifetime Achievement Award   
Brewin Dolphin Commodores' Cup - Tactical evening ahead for the fleet   
International Moth Worlds: Greenhalgh and Rashley tied at the top   
PWA Pozo World Cup - Fantastic finale determines winners   
Six Metre Class British Open Championship - Llanoria and Valhalla win   
Anna Tunnicliffe set to compete at the CrossFit Games   
America's Cup: Oracle Team USA holds foiling camp at Wangi SC   
Volvo Ocean Race: Abu Dhabi OR completes double Atlantic crossing   
Volvo Ocean Race: Team SCA has a 'pull through day' off the Canaries   
No tiller sailing - how to steer using just the sails + Video   
International Moth Worlds: Three bullets in a row for Greenhalgh   
U.S. Junior Women’s Singlehanded Championship - Sophia Reineke wins   
BIC Techno 293 Worlds 2014 - Day 0 Opening   


For this week's complete news stories select    Last 7 Days
   Search All News
For last month's complete news stories select    Last 30 Days
   Archive News







Sail-World.com  


















Switch Default Region to:

Social Media

Asia

Australia

Canada

Europe

New Zealand

United Kingdom


http://www.sail-world.com/event_images/image/Twitter_logo_small.png http://www.sail-world.com/event_images/image/FaceBook-icon.png  http://www.sail-world.com/event_images/image/RSS-Icon.png

United States

Cruising Northern

Cruising Southern

MarineBusiness World

PowerBoat World

FishingBoating World

 

Contact

Commercial

News

Search

Contact Us

Advertisers Information

Submit news/events

Search Stories/Text

Feedback

Advertisers Directory

Newsletter Archive

Photo Gallery

 

Banner Advertising Details

Newsletter Subscribe

Video Gallery

Policies

 

 

 

Privacy Policy

 

 


Cookie Policy

 

 



This site and its contents are © Copyright TetraMedia and/or the original author, photographer etc. All Rights Reserved.  Photographs are copyright by law.  If you wish to use or buy a photograph contact the photographer directly.
XLXL WAS US
LocalAds   DE  ES  FR  IT