Dredging mitigation - coral relocation - Saudi Arabia

Client: Saudi Aramco

Reef Ball Australia successfully conducted the first coral relocation project in Saudi Arabia, rescuing 523 imperiled coral colonies out of a dredge zone and established them in a matching area 700m to the west. Monitoring over 6 months has confirmed <5% mortality even after heavy sedimentation from the dredging.

The relocation phase had to be completed within 13 days in order to prevent delays to the dredging operation.

Trials were conducted to determine the length of exposure to air the coral (mainly Cyphastrea sp) could withstand and found 10 minutes was a safe working time. Sunburn to the coral and warm (36-38C) nearshore water were threats that had to be managed.

Coral heads were carefully removed and staged by certified coral handlers and the crates then covered and quickly loaded into either a boat or 4WD and delivered to the relocation site and back in the water within 6mins.

Rescued corals were stabilised at the new location using a variety of techniques including attachment to specially constructed concrete bases.

While the relocation was completed within 13 days, we conducted a survey of the area beforehand to confirm the number and type of coral to be moved, the method of removal required and potential relocation sites. Choosing a relocation site must be done carefully to ensure conditions match those from which the corals came.

A detailed analysis of existing water quality data and dredge plume modelling was conducted in order to determine the boundaries of imperiled and threatened corals and the distance that rescued corals would need to be moved to avoid excessive sedimentation from the plume.

The project included ongoing monitoring for the first 60 days and then periodically during the dredging operation.

Creating Fishing hotspots - New South Wales & Victoria

NEW SOUTH WALES

The New South Wales and Victorian Departpment of Primary Industries (DPI) are using Reef Balls to enhance recreational fishing.

Recreational target species found on the reefs include yellowfin bream, silver trevally, samson fish, eastern blue groper, leatherjackets, flathead, snapper, whiting, flathead, yellowtail kingfish, tailor, tarwhine, and amberjack.

The NSW Department of Primary Industries has deployed over 1500 Reef Balls in Lake Macquarie, Botany Bay, St Georges Basin, Merimbula Lake, and Lake Conjola to create 'fishing havens' and enahance recreational fishing.

Comprehensive monitoring is being conducted on these reefs by DPI and the quantity and diversity of fish life inhabiting them has exceeded expections and the program is being expanded.

In November 2008, DPI deployed 420 Reef Balls in Lake Conjola (NSW) and this is the first reef to use 3 different size Reef Balls. Varying the size of units helps increase the diversity of habitat which results in the reef being utilised by a greater variety of fish. Monitoring results only one month after deployment show an impressive number of fish already taking up residence.

VICTORIA

In May 2009, VIC DPI finished construction of three Reef Ball 'recreational fishing reefs' along the 11m depth contour at the north-east corner of Port Phillip Bay. The objective of the reefs are to enhance snapper fishing and the DPI will be conducting two years of monitoring including surveys of catch rates.

Each reef comprises of three sizes of Reef Ball (Pallet Ball, Bay Ball, Mini Bay) and configured to match the preferred habitat topography of the target snapper.

Record Catch!

And as quoted by one recreational fisher, "...the reefs are definitely working!" Ian Jones caught a record 12.3kg snapper on the Aspendale Reef (Rec Reef) in late November 2010 and commented that there were plenty of 5kg snapper on the reef too. Ian is one of the recreational fishers commissioned to fish the reefs as part of the Governments monitoring program.

Ian has been fishing Rec Reef at set intervals since its deployment. He has observed that there were plenty of undersize snapper and flathead on the reef soon after deployment. After one year there are still plenty of younger snapper (pinkies) but they are catching larger snapper and flathead and the commercial fishers are catching decent size fish on the other recreational fishing reefs as well. Ian also stated there are plenty of baitfish schooling over the reefs that the undersize snapper are feeding on.
 

Enhancing Canal Estates - Western Australia
Peel-Harvey Catchment Council Inc commissioned a feasibility study and recommendations for marine habitat enhancement of canal estates and natural waterways, including a financial plan and implementation program.  This was then followed up by the Peel Region Fish Stocking & Management Association which is managing deployment of the Reef Balls for the program.

Cyclone-proof breakwater - Antigua
The largest Reef Ball breakwater for beach protection built to date using over 1500 Reef Balls weighing up to 5 tonnes each. Included the transplantation on to the Reef Balls of over 17 tonnes of rescued corals from pending dredge sites.

Fish for Life - North Sulawesi

PT Newmont Minahasa Raya
An excellent example of how the mining industry can work with the local community to create a lasting asset.  The reefs support up to 120 species of fish, many of which are important commercial species.

PT Newmont Minahasa Raya (gold mine) contracted local fishermen to manufacture the Reef Balls and then assisted with their deployment to create a fishing resource that will provide for the local community long after the mine closed.

The Reef Balls also helped mitigate damage to coral from dynamiting.  The project included site assessment, construction, training, deployment methodology and reef configurations. This is now the largest non-government Reef Ball reef in the world with over 3200 modules deployed.

Annual surveys of the reefs have been conducted showing colonisation stabilised within 7-8 years. Number of species for the six reefs varied from 50 to 120 and coral growth has been excellent. A paper discussing the fish and coral data is currently in production.

Reef Ball Breakwater - Turtle Island - Sabah
Survey of five islands and recommendations of how Reef Ball breakwaters could be used to reduce erosion and maximise environmental enhancement.  Construction of a Reef Ball breakwater was completed in August 2007.

Grouper and Corals - United Arab Emirates
Enhancement of fisheries and corals around a private island using Reef Balls ranging in size from 15 kg to 3000kg. The project included setting up a construction site and training of local staff. Extensive site investigations were conducted to determine which areas would achieve the desired results. Four reef designs were then prepared for the priority areas and included unique configurations and a ‘stepping stone’ reef linking a transplanted mangrove stand with the adjacent reef. Imperiled corals affected by dredging were rescued and transplanted onto the Reef Balls to accelerate growth.

Reef Ball Australia
Mob: 0400 520 471