Photo by U. Engelhardt; © GBRMPA

At a press conference in Townsville in November 1995, the chair of the Crown-of-Thorns Starfish Research Committee, Professor Graham Mitchell, outlined the current status of COTS populations on the Great Barrier Reef and abroad. Significantly, recent trends of increasing starfish populations on the Great Barrier Reef appear to coincide with similar increases in many other parts of the Indo-Pacific region. It seems that we are not alone in having to face up to the effects of a new outbreak cycle.

Some comfort may be taken from the fact that we have detected this outbreak at a much earlier stage than previously possible. Those who might be directly affected should benefit from the increased lead time available to prepare for the changing situation on the Reef. Reef-based tourism operations in particular have been able to initiate local-scale controls at an early stage. An ongoing commitment to conducting these strategic controls in important areas should ensure that valuable diving and snorkelling sites can be protected and maintained. The controls strategy project currently under way at Lizard Island (conducted by Reef Research & Information Services and Lizard Island Research Station) will shed some additional light on the best and most effective way to use the established method of injecting starfish with a sodium bisulphate solution.

FINE-SCALE SURVEYS (CRC REEF/GBRMPA)

At the time this edition of COTS COMMS was written, the fine-scale surveys for 1995-96 were still in full swing and the first three trips of this year's sampling program have already confirmed the anticipated trends. Regular readers may recall that at the end of the 1994-95 season a number of survey reefs in the northern parts of the Cairns Section were classified as Incipient Outbreaks (IO). These reefs were characterised by the presence of relatively large numbers of juvenile and immature starfish. Classification of these reefs was based on the assumption that most of the observed juveniles would survive and become part of the mature population in 1995-96. It appears that this assumption has been a valid one with our northern survey reefs showing the expected increases in the densities of mature populations. The bottom line is that the majority of mid-shelf reefs between Lizard Island and Port Douglas now support either localised or reef-wide outbreaks. Average densities of mature starfish on these reefs are typically three to ten times above the sustainable threshold of approximately 30 mature starfish per hectare.

Again, the 1995-96 surveys detected substantial numbers of juvenile starfish on many reefs indicating that the current situation is likely to worsen over the next couple of years or so. Currently, starfish activity appears largely restricted to mid-shelf reefs. COTSWATCH reports indicate that, at this stage, outer shelf reefs support only low numbers of starfish. A more detailed summary of the results for 1995-96 will appear in the next edition of COTS COMMS. Stay tuned!

COTSWATCH - REEF-USER SURVEY SCHEME

In my memory, 1995 will be fondly remembered as the most successful year yet of this valuable public participation program. Thanks to the ever increasing number of dedicated COTSWATCHERS the scheme has gone from strength to strength. A record number of completed forms has greatly increased our knowledge of the geographic extent of recent population increases. Nearly 650 individual site reports were received in 1995. A sincere thank you goes to everyone who has contributed to the success of the Reef-user scheme. A list of all known contributors in 1995 follows:

G Bennett / Cairns, S Wood / Mission Beach, J Anderson / Cairns, J Cowie / Freshwater, J Cruise / QDEH Gladstone, K Roach / Cairns, R Vanstan / Cairns, S Singleton / Cairns, R Stutely / Townsville, G Svensson / Cairns, F Muir / QDEH Cairns, J Low / QDEH Cairns, M Short / QDEH Cairns, G Kelly / QDEH Cairns, C Williams / QDEH Cairns, S Martin / QDEH Cairns, J Haig / QDEH Cairns, G LaPraik / QDEH Cairns, G Connett / Port Douglas, A Van Welderen / Cairns, G McGarry / Cairns, A Lloyd / Ingham, D Anderlini / Whiterock, G Manahan / Cairns, K Larsen / Cairns, D St John / Earlville, M Schaer / Cairns, P Ward / Cairns, J Purcell / Cairns, B Knuckey / QDEH Gladstone, J Olds / QDEH Gladstone, K Menkens / Cairns, L Lamb / QDEH Townsville, C Dunk / Townsville, F Gunst / Edmonton, C Hopkins / Cairns, B Kahn / Port Douglas, R Miller / Port Douglas, P Wright / Port Douglas, K Jesienowski / Port Douglas, D Cowie / Freshwater, N Purdy / Cairns, B Legg / Rockhampton, E Green / Cairns, S Svensson / West End, S Simpson / Port Douglas, K Burns / Cairns, D Ball / QDEH Airlie Beach, G Byron / QDEH Rockhampton, P O'Neill / QDEH Rockhampton, R Schutte / Cairns, W Kibble / Cairns, J Thompson / Airlie Beach, R Moran / Kuranda, A Marshall / Port Douglas, S Richards / Cairns, B Heinrich / Proserpine, R Reddacliff / Stratford, B McCormack / Parramatta Park, J Richter / QDEH Rockhampton, K Cutmore / QDEH Gladstone, A Frisch / Townsville, R Buck / QDEH Mackay, S Moon / Cairns, G Johnstone / Port Douglas, P Pilkington / Lizard Island, I Stapleton / Cairns, R Toff / Cairns, G Rochester / Cairns, P Harvey / Mission Beach, A Lloyd-Cahill / Smithfield, S Whelan / Earlville, J Stoddart / Cremorne, J Green / Cairns, I Drayton / Lizard Island, K Steinbeck / Holloways Beach, G Leeon / Cairns, J Richardson / Cairns, J Ashmore / Cairns, S Fisher / Mackay, M Abela / Hermit Park, C Purdon / QDEH Townsville, D Wiseman / Cairns, C Taylor / Earlville, G Lane / Trinity Beach, S Woodford / Cairns, R Adolf / Palm Cove, C Schoenberg / Townsville, D Robb / Dingo Beach, J Weisgerber / Cairns, M Allen / Cairns, M Greet / Port Douglas, R Graafsma / Cairns, B Tatchull / Cairns, P Heatherwick / Port Douglas, L DeVantier / Townsville, E Turak / Townsville, T Rouphael / Townsville, J McKay / QDEH Cairns, W Oxley / Townsville, M Smith / Cairns, J Ayres & S Waterczyk / Indian Head Park, P Erasmus / Townsville, I Fleetwood / Gladstone, Z Wreid / Gladstone, Staff on 'Undersea Explorer' / Port Douglas, D Walkden / Townsville, M Portefaix / QDEH Cairns, R Clarke / QDEH Cairns, W McFarlane / Cairns, N Gill / Worcester, D Pana / Trinity Park.

AUSTRALIAN NAVY DIVERS

Our understanding of the COTS phenomenon relies heavily on knowing what is actually happening out there on the Reef. Whilst broad- and fine-scale surveys of COTS cover a substantial number of reefs, additional information coming in from other parts of the Reef is much needed and always appreciated. The latest edition to our growing army of COTSWATCHERS actually comes courtesy of the Australian Navy. A bunch of dedicated volunteer divers from the Operations Support Department of HMAS Albatross led by sub-lieutenant Dwayne Kirk have offered their services to assist in surveying 'new' grounds. By the time you read these lines, the Navy team will have completed a week-long survey of selected reefs in the Cairns to Innisfail area. Well done guys.

BROAD-SCALE SURVEYS (AIMS)

The AIMS monitoring team recently returned from their annual surveys of reefs in the Swain and Capricorn Bunker sectors of the Marine Park. The status of COTS populations in these southern sectors remains largely unchanged. All survey reefs retained the classification assigned after last year's surveys. Two reefs (22-088 and Horseshoe Reef) in the Swain sector continue to support active outbreaks, with small numbers of starfish also being recorded on another six reefs. Strong signs of coral recovery following an outbreak in 1993-94 were evident on Gannet Cay Reef. A population of COTS has been present on this reef for at least the past 10 years. Following the peak of an outbreak a few years ago, recent reef recovery at Gannet Cay has resulted in an increase in the median coral cover from category 1 (11-30%) up to category 2 (31-50%) this year.

Only limited COTS activity was recorded on reefs in the Capricorn Bunker sector. However, the monitoring team notes that while only a few starfish were recorded, they are the first sightings of COTS in this sector for many years.

NEW CROWN-OF-THORNS STARFISH BROCHURE

The CRC Reef Research Centre, in conjunction with the Great Barrier Reef Marine Park Authority, recently released a new popular-style pamphlet updating the latest COTS situation on the Reef. This glossy full colour fold-out publication provides brief overviews of some important topics relevant to the COTS phenomenon such as the recent history of outbreaks, the current status of COTS on the Great Barrier Reef and abroad, GBRMPA's policy on controls, as well as some basic facts about the biology of the animal. The pamphlet is being widely distributed to Reef-users along the Great Barrier Reef. Copies are available direct from the Education and Information Section at GBRMPA, the CRC Reef Research Centre and various offices of the Queensland Department of Environment and Heritage.

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Great Barrier Reef Marine Park Authority
PO Box 1379 TOWNSVILLE QLD 4810. Phone: (077) 500 700, Fax: (077) 726 093
E-mail: registry@gbrmpa.gov.au