Past Reef health updates

May 2020 update

Sea surface temperatures

Sea surfaces temperatures throughout the Marine Park were generally average at the end of May. Inshore regions in central and southern areas were up to 2°C cooler.

Reef health

There continues to be a limited amount of post-bleaching surveys being conducted due to COVID-19 travel restrictions.

The Eye on the Reef program continue to receive reports that coral disease is scattered with low-level impacts.

There are anecdotal reports of coral recovery at John Brewer Reef, Moore Reef, Lady Elliot, Heron Island and Low Isles.

Coral recovery at Keppel Islands

As part of the Great Barrier Reef Marine Park Authority’s Marine Monitoring Program, the Australian Institute of Marine Science conducted surveys in the Keppel Islands in early May. This region had a high level of bleaching during the 2019-2020 summer bleaching event.

Reports from these surveys show patchy coral mortality and low levels of coral disease. However, on average 15% of coral cover remains bleached white. This suggests limited recovery and the potential for further decline in coral cover.

Humpback whales

We’ve received multiple reports through our Eye on the Reef sightings network of humpback whales in the Whitsundays and Townsville areas. From May to September, whales make the trek from Antarctica to the Reef’s warmer waters to court, mate, give birth or rear their calves.

April 2020 update

We acknowledge the significant impact COVID-19 is having on Reef related-industries and communities and welcome additional support announced by the Australian Government for tourism and regional economies.

We are continuing to provide updates on Reef health during this time – updates will be monthly until the start of the 2020-21 summer.

2019-20 wet season wrap-up

Northern Australia’s 2019-20 wet season was the driest since 2004-05, and the second well-below average wet season in a row, according to the Bureau of Meteorology. Tropical cyclone numbers were also well below the long-term average.

Temperature and rainfall outlook

Sea surface temperatures throughout the Marine Park were generally average at the end of April.

The Bureau of Meteorology is forecasting warmer and wetter than average conditions for Queensland through to August.

Reef snapshot: summer 2019-2020

In April 2020, we released the first Reef snapshot with the Australian Institute of Marine Science and CSIRO. It is a concise, easy to understand summary of how the Reef has fared over the past summer, what this means for coral and the actions being taken to help coral health. The snapshot found:

Northern (Cape York – Lizard Island): Moderate hard coral cover and low levels of crown-of-thorns starfish (COTS). Bleaching moderate to severe on mid-shelf and inshore reefs, with little to no bleaching on outer-shelf reefs.

Central (Lizard Island – Whitsundays): Moderate hard coral cover in Cairns and low in Innisfail overall, with no COTS observed. Moderate bleaching levels near Cairns, but generally more widespread and severe bleaching on mid-shelf reefs further south (except the Whitsundays).

Southern (Whitsundays – Cap-Bunkers/Swains):  Hard coral cover and active COTS in the Pompeys, high levels of hard coral cover in the Cap-Bunkers and moderate levels of hard coral cover and COTS outbreaks in the Swains. Variable bleaching observed overall, with two-thirds of reefs moderately to severely bleached in the Pompeys and Swains.

Coral bleaching recovery

Surveys of post-bleaching recovery and mortality have not been conducted due to COVID-19 social distancing and travel restrictions. As a result, we are mostly reliant on reports from locals and tourism operators.

Magnetic Island is showing signs of recovery from the recent mass bleaching event in the 2019-20 summer. Reports show corals and giant clams are regaining some of their function/colour.

Footage from four reefs offshore from Cairns show healthy coral with small amounts of bleaching.

Early reports from the Marine Monitoring Program show encouraging signs of recovery on inshore sites in the Burdekin and Keppels Islands.

Observations of coral disease submitted through the Eye on the Reef program indicated scattered, low-level impacts.

Crown-of-thorns starfish management

The crown-of-thorns starfish control vessels commenced culling at four reefs in the Capricorn-Bunker Group which are currently in active outbreak status.

Rare sighting reported on Eye on the Reef

Footage of a rare and endangered ornate eagle ray was sighted near Lady Elliot Island. There are only about 50 sightings recorded for this species world-wide.

Weekly Reef health update — 02 April 2020

Sea surface temperatures

As of 31 March 2020, sea surface temperatures (SSTs) across the Great Barrier Reef were near average and well below the temperatures that caused mass coral bleaching this summer.

Although temperatures decreased, the effects of prolonged thermal stress are still being observed across the Marine Park and it will take time for bleached corals to recover and regain their colour and health.

Reef-wide aerial surveys to determine the extent and severity of coral bleaching across the Reef concluded on Friday 27 March 2020.

The Australian Research Council Centre of Excellence for Coral Reef Studies at James Cook University will analyse the aerial survey data in the coming weeks and release the information.

The aerial surveys indicate variability at a whole of Reef scale, which will only be shown once a full analysis and mapping occurs.

Some initial observations from the aerial surveys:

• Widespread moderate to severe bleaching across much of the Reef Severe bleaching was more widespread than in previous bleaching events.
• Areas, mostly well offshore, had no or low level bleaching.
• Some areas have reefs with a mix of negligible, moderate and severe bleaching (the southern offshore reefs of the Marine Park).
• There are reefs that severely bleached for the first time in 2020 and other reefs that bleached severely in 2016, 2017 and 2020.
• Major tourism areas of the Reef mostly experienced no, negligible or moderate bleaching only - the exception is one area in the southern part of the Marine Park with severe bleaching.

Future outlook

From past bleaching events the Marine Park Authority anticipates corals on reefs with no or negligible bleaching will mostly recover and survive this event. Moderately bleached reefs are likely to show mixed responses depending on their history of disturbance.

Corals on reefs with severe bleaching, however, are likely to have significantly higher, though variable, mortality rates. While there are some in-water surveys continuing at present, due to COVID-19 travel and social distancing restrictions, on-water operational activity is constrained.

The Long-Term Monitoring Program conducted by the Australian Institute of Marine Science remain an important source of information on the health of coral reefs in the Great Barrier Reef Marine Park. The Marine Park Authority will move to monthly Reef Health updates.

Weekly Reef health update — 26 March 2020

The Authority acknowledges the significant impact the COVID 19 virus is having on Reef related industries and communities.  The Authority will continue to provide updates on Reef Health during this time.

Sea surface temperatures

As of 24 March 2020, sea surface temperatures (SSTs) across the Reef were mostly average and additional thermal stress is unlikely to accumulate.

Although temperatures decreased, the effects of prolonged thermal stress are still being observed across the Marine Park and we continue to receive reports of coral bleaching.

Reef-wide aerial surveys to determine the extent and severity of coral bleaching are currently underway.

The Authority has an observer on these surveys conducted by the Australian Research Council Centre of Excellence for Coral Reef Studies at James Cook University.

Aerial surveys conducted last week showed most offshore reefs north of Cairns had no or low levels of bleaching. Moderate to severe bleaching was observed on inshore and mid-shelf reefs over this area.

Inshore and offshore reefs south of Cairns, particularly between Tully and Townsville, showed severe bleaching.

There was an area offshore in this northern section where reefs were more moderately bleached, including high value tourism reefs.

Inner and mid-shelf reefs surveyed between Townsville and Mackay were mostly severely bleached, but some were only moderately bleached in this central section, including high value tourism reefs.

Reefs in the Swains Pompey Reef complexes (the extreme southeast of the Marine Park) surveyed on 25 March 2020 show high variability in bleaching.

There was about one-third with no or minor bleaching, one-third with moderate bleaching and the remaining third had severe bleaching. There was no consistent north-south or inshore-offshore pattern.

Next week's outlook

Aerial surveys will be completed later this week and the analysis of the aerial survey information will occur in the weeks to follow. After this analysis, we will provide further information how the whole Reef fared this summer.

Media statement

On 26 March 2020 the Marine Park Authority issued a media statement that confirms mass coral bleaching is occurring on the Great Barrier Reef, with very widespread bleaching detected.

Weekly Reef health update - 27 February 2020

Temperature

While recent cloud and rain provided cooling to some parts of the Great Barrier Reef, we are continuing to monitor the situation because the risks have not gone away.

Local weather conditions over the next few weeks will play a key role in determining outcomes for the Reef this summer.

Coral bleaching has been occurring on parts of the Reef where thermal stress has accumulated the most over summer.

In-water loggers and satellite data

A variety of information is used to understand conditions, including in-water temperature loggers monitored by the Australian Institute of Marine Science and satellite observations from the Bureau of Meteorology.

Given the recent rain and cloud cover, we don’t have a complete picture of sea surface temperature trends and current conditions. We’ll get abetter understanding when satellites can see the Reef again.

In-water temperature loggers monitored by the Australian Institute of Marine Science currently indicate cooling over the last week at most locations across the Reef.

Forecast tools from both the Bureau and the National Oceanic and Atmospheric Association (NOAA) indicate a high level of thermal stress is likely to build throughout the Marine Park for the rest of February and into March.

Recent cloud cover may have restricted the ability of some satellites to accurately measure sea surface temperatures. As a result, modelled sea surface temperatures may appear warmer than it actually is, so data should be interpreted with caution.

Aerial and in-water surveys

We’ve continued to receive reports of coral bleaching from our aerial surveillance, in water surveys and from tourism operators and reef users.

These show inshore and mid-shelf reefs assessed in the far north (north of Princess Charlotte Bay) mostly have widespread bleaching affecting most coral types, whereas offshore reefs assessed in this area show minimal to no bleaching.

Observations over large parts of the remainder of the Reef show no bleaching or isolated minor coral bleaching.

For example, observations of reefs from Bowen to offshore Mackay and mid shelf reefs between Ingham and Cairns showed no or minimal coral bleaching during aerial surveillance last week and into the weekend.

In some other locations, such as Cleveland and Halifax bays near Townsville, moderate to severe bleaching was observed on inshore fringing reefs. We’ve also received reports of more prevalent bleaching in some parts of the Capricorn Bunker Group.

Rainfall

As of 26 February 2020, most of the Great Barrier Reef coast and catchment received rainfall, with the highest totals falling just north of Mackay.

Most river systems within the Marine Park catchment are currently below flood level. Salinity levels remain mostly normal, however some inshore areas between Townsville and Port Douglas and a small area near the Fitzroy River recorded lower salinity levels.

Weekly Reef health update – 20 February 2020

There’s important information about current conditions on the Great Barrier Reef in today’s Reef health update.

Water temperatures across the Reef are increasing and reaching levels where some bleaching is being observed.

We are investigating this — spot checks by divers, helicopter patrols, and citizen science observations are helping us build a bigger picture.

As was the case last summer, local and regional weather conditions have the potential to change this outlook and are a critical factor in outcomes this summer. However, with current thermal stress observations and forecasts, further bleaching may develop in the Great Barrier Reef this summer.

We’re working closely with the Australian Institute of Marine Science, James Cook University, other science partners, Traditional Owners and the tourism industry to monitor conditions on the Reef throughout the summer.

Weekly Reef health update – 13 February 2020

Rainfall

As of 11 February 2020, most of the Great Barrier Reef coast and catchment received rainfall, with the highest totals falling in the northern Cape York Peninsula and in the Fitzroy River catchment.

All rivers systems within the Marine Park catchment are currently below flood level. Salinity levels remain mostly normal, apart from a small area in Princess Charlotte Bay and coastal areas near the Tully and Herbert rivers where lower salinity levels were recorded.

Temperature

The Bureau of Meteorology’s ReefTemp tool indicates sea surface temperatures within the Marine Park have increased slightly since the previous update.

As of 11 February 2020, most of the Marine Park was 0.5 to 1.5°C above average.

Some inshore to offshore areas in the Far Northern, Central and Southern management areas were 2 to 3°C warmer. These areas also accumulated the most thermal stress since the start of summer.

Monitoring by the United States National Oceanic and Atmospheric Administration (NOAA) shows most of the Marine Park is on “warning” for bleaching to occur.

Large parts of the Torres Strait and Far Northern management area of the Marine Park are on “Bleaching Alert Level 1.” (see table below)

However, there is variability between the satellite-based models and more local in-water readings.

In-water temperature loggers monitored by the Australian Institute of Marine Science currently indicate a high risk of bleaching at Myrmidon Reef and an extreme risk of bleaching at Davies Reef —both in the Central management area.

A medium risk of bleaching is indicated in the Keppel Islands, with loggers in the northern half of the Marine Park indicating no or low risk of bleaching.

Forecast tools from both the Bureau and NOAA agree some level of thermal stress is likely to be seen throughout the Marine Park in March.

Bleaching levels explained

The United States National Oceanic and Atmospheric Administration (NOAA) use several categories in their heat stress monitoring for coral reefs:

• No stress: there is no stress level for corals, no hotspots and no bleaching
• Bleaching Watch: there is at least one temperature hotspot in the area and marine managers are keeping an eye on this area
• Bleaching Warning: bleaching is possible, there are several hotspots with elevated temperatures
• Bleaching Alert Level One: significant bleaching is likely, there multiple hotspots with elevated temperatures
• Bleaching Alert Level Two: the highest level, severe bleaching and significant mortality are likely.

Cyclones

Ex-tropical cyclone Uesi is currently located 495km north-northeast of Lord Howe Island.

It is expected to continue moving slowly to the southwest and expected to cause destructive winds at Lord Howe Island later today.

The Bureau of Meteorology is not expecting direct cyclone impacts on the Queensland east coast.

Weekly Reef health Update – 6 February 2020

Rainfall

As of 3 February 2020, most of the Great Barrier Reef coast and catchment received rainfall, with the highest totals between Cooktown in the far north and Cape Upstart in the south.

All rivers systems within the Marine Park catchment are currently below flood level.

Temperature

The Bureau of Meteorology’s ReefTemp tool indicates sea surface temperatures within the Marine Park remained above average, but stable, since our previous update.

As of 4 February 2020, most of the Marine Park was 0.5 to 1.5°C above average, except for some inshore to mid-shelf areas in the Far Northern and Southern management areas that were 2 to 2.5°C warmer. These areas have also accumulated the most thermal stress since the start of summer.

The United States National Oceanic and Atmospheric Administration (NOAA) is indicating large parts of the Torres Strait — along with most of the northern half of the Far Northern management area — are on Bleaching Alert Level 1.

It is important to note the recent cloud cover has compromised the ability of some of the satellites to see what's happening on the ocean’s surface – so, the data should be interpreted with caution.

For the remainder of the Marine Park, most of the mid-shelf and offshore reefs are on “Watch,” except for south of the Whitsundays where inshore and mid-shelf areas are on “Warning.”

In-water temperature loggers monitored by the Australian Institute of Marine Science are currently indicating a medium risk of bleaching at Heron Island and in the Keppel Islands, with loggers north of these indicating no or low risk of bleaching.

Forecast tools from both the Bureau and NOAA agree some level of thermal stress is likely to be seen throughout the Marine Park in February.

Bleaching levels explained

The United States National Oceanic and Atmospheric Administration (NOAA) use several categories in their heat stress monitoring for coral reefs:

• No stress: there is no stress level for corals, no hotspots and no bleaching
• Bleaching Watch: there is at least one temperature hotspot in the area and marine managers are keeping an eye on this area
• Bleaching Warning: bleaching is possible, there are several hotspots with elevated temperatures
• Bleaching Alert Level One: significant bleaching is likely, there multiple hotspots with elevated temperatures
• Bleaching Alert Level Two: the highest level, severe bleaching and significant mortality are likely.

Cyclones

There is currently a tropical low located over the northern Coral Sea. This system is not expected to develop significantly in the short-term, but may strengthen towards tropical cyclone intensity late this weekend or early next week.

Weekly Reef health update - 30 January 2020

A tropical low near the southern coast of the Gulf of Carpentaria caused significant rainfall and cloud cover across northern Australia over the past week, including across the Great Barrier Reef catchment.

Most of the Great Barrier Reef coast and catchment received rainfall, with the highest totals between Princess Charlotte Bay in the far north and Shoalwater Bay in the south.

However, this rainfall has not resulted in flooding of the catchment’s major river systems and it is expected to have negligible impacts on the Marine Park.

The recent rain and cloud cover conditions over much of the Marine Park may have some cooling influence on sea surface temperatures over the coming weeks and this will continue to be monitored.

Temperature

The Bureau’s ReefTemp indicates sea surface temperatures in the Marine Park have increased since the previous update.

As of 27 January, some inshore to mid-shelf areas in the Far Northern and Southern management areas were 2 to 2.5°C above the January average.

These are the areas that have also accumulated the most thermal stress in the Marine Park since the start of summer.

Local and regional weather conditions will have a key influence on sea surface temperatures over the next few weeks, and we will continue to monitor the situation closely.

The United States National Oceanic and Atmospheric Administration (NOAA) is indicating that parts of the Torres Strait — and the most northern part of the Far Northern management area — are on Bleaching Alert Level 1.

The area from approximately Shelburne Bay south to Cairns is on Bleaching Warning.

From Cairns to the southern boundary of the Marine Park, most inshore to mid-shelf areas are on Warning, while outer shelf areas are on Watch.

In-water temperature loggers monitored by the Australian Institute of Marine Science are currently indicating a high risk of bleaching at Thursday Island in the Torres Strait, and a medium risk of bleaching at Lizard Island in the northern Marine Park.

All other logger locations south of Lizard Island currently indicate no or low risk of bleaching.

Forecast tools from both the Bureau and NOAA agree that some level of thermal stress is likely to be seen throughout the Marine Park in February.

Bleaching levels explained

The United States National Oceanic and Atmospheric Administration (NOAA) use several categories in their heat stress monitoring for coral reefs.

• No stress: there is no stress level for corals, no hotspots and no bleaching.
• Bleaching Watch: there is at least one temperature hotspot in the area and marine managers are keeping an eye on this area.
• Bleaching Warning: bleaching is possible, there are several hotspots with elevated temperatures.
• Bleaching Alert Level One: significant bleaching is likely, there multiple hotspots with elevated temperatures.
• Bleaching Alert Level Two: the highest level, severe bleaching and significant mortality are likely.

Reef health

Reports from our Eye on the Reef network indicated isolated instances of low level coral bleaching and coral disease in the Marine Park.

Active crown-of-thorns starfish outbreaks continue in the central and southern Marine Park.

Weekly Reef health update -  24 January 2020

Temperature and rainfall

Sea surface temperatures in the Marine Park increased over the past week, mainly within the central and southern inshore areas in and throughout the far northern management area.

The Bureau of Meteorology’s ReefTemp tool shows an increasing level of thermal stress in the far northern sector and in inshore and mid-shelf areas in southern area.

Above-average air temperatures are expected to persist for much of the country into April, with a roughly equal chance of wetter or drier conditions than average during this period.

Forecast tools from the Bureau and the National Oceanic and Atmospheric Association currently predict a moderate risk of thermal stress throughout all sectors of the Marine Park over the coming months, but particularly within inshore areas.

An area within the Torres Strait is on Bleaching Alert by the National Oceanic and Atmospheric Administration with elevated water temperatures concentrated to the north west of the region.

Both the El Nino-Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) are now neutral and likely to remain so into April — when these main climate drivers are neutral, Australia’s climate can be influenced by more local or short-term drivers.

Reef health

The latest Australian Institute of Marine Science survey reports for the far northern area of the Great Barrier Reef show overall hard coral cover in the Cape Grenville and Princess Charlotte Bay sectors was moderate (10 to 30 per cent).

Per cent coral cover in Cape Grenville was unchanged while there was a slight decrease in Princess Charlotte Bay.

Coral bleaching was widespread, but restricted to low levels, with no crown-of-thorns starfish outbreaks reported.

Weekly Reef health update -  17 January 2020

Sea surface temperatures

Sea surface temperature anomalies in parts of the Marine Park increased slightly over the past week, mainly in the Far Northern area.

The Bureau of Meteorology’s ReefTemp tool also suggests there is a low level of thermal stress accumulation in the Far Northern and inshore Southern areas.

Above average temperatures are likely to continue for much of Australia into April. Most of eastern Queensland is likely to be drier than average through to the end of this month.

Forecast tools from the Bureau and National Oceanic and Atmospheric Administration currently predict a moderate risk of thermal stress throughout the Marine Park over the coming months.

Eye on the Reef

Reports from the Eye on the Reef network have indicated only isolated instances of low level coral bleaching and coral disease in the Marine Park. Active crown-of-thorns starfish outbreaks continue in the central and southern Marine Park.

Weekly Reef health update -  10 January 2020

Temperature and rainfall

Over the past fortnight, sea surface temperatures in the Marine Park have been mostly average, apart from some areas of the Far North which were up to 2°C above average.

The Bureau of Meteorology’s ReefTemp tool indicates there is currently a low level of thermal stress accumulation around inshore areas in the Far Northern and Southern sectors of the Marine Park.

Above-average temperatures are likely to continue for much of Australia including Queensland into April. Most of eastern Australia is likely to be drier than average through to the end of this month.

Forecast tools from the Bureau and National Oceanic and Atmospheric Administration currently predict a moderate risk of thermal stress in the Marine Park over the coming months.

Tropical cyclones

The first tropical cyclone of the season for Australia, tropical cyclone Blake, made landfall on Wednesday morning 8 January 2020 in Western Australia.

A second tropical system currently over the Arafura Sea (west of the Pacific Ocean) is forecast to develop to tropical cyclone intensity in the coming days, potentially making landfall on the north coast of the Northern Territory in Australia.

There are currently no significant tropical low systems in the eastern region and none expected to develop.

Weekly Reef health update -  20 December 2019

Temperature and rainfall

Rainfall across northern Australia has been well below average, with most of the tropics receiving less than 20 per cent of normal December rainfall.

In the past few days, a low intensity heat wave has been affecting most of Queensland, apart from isolated areas along the coast.  The southwest and western parts of the State reported severe heatwaves.

Over the past fortnight, sea surface temperatures throughout the majority of the Marine Park have been average to slightly above average, apart from isolated inshore areas of the southern Marine Park which were up to 2°C above average.  The Bureau of Meteorology (BoM) ReefTemp tool indicates there is currently a low level of thermal stress accumulation throughout the Marine Park, and it is probable that this heating over the past few weeks has negated any buffer that existed in the Marine Park following a cooler winter.

The patterns of above-average temperatures and below-average rainfall are predicted to continue for northern Australia, at least until the monsoon becomes established in mid- to late-January – this is likely to mean calm, clear and dry conditions for the next few weeks which could likely contribute to thermal stress accumulation. While there is no immediate threat of significant thermal bleaching, the Marine Park Authority remains on watch, with both BoM and United States’ National Oceanic and Atmospheric Administration showing a bleaching watch situation for the far northern Marine Park and inshore regions in the Central and Southern management areas.

Eye on the Reef

Reports on another round of coral spawning have been received through the Eye on the Reef sightings network.

Crown-of-thorns starfish (COTS) management program

The Reef Joint Field Management Program COTS response team have discovered a new outbreak of coral eating starfish on a priority reef in the offshore central Marine Park.  A control team will be tasked with culling COTS on this reef in the New Year.

Weekly Reef health update -  13 December 2019

Temperature and rainfall

Conditions are currently hot and dry across the Great Barrier Reef catchment and are likely to remain so well into January.

Over the past few days, a low intensity heat wave has been affecting most of Cape York Peninsula.

The Australian Bureau of Meteorology’s ReefTemp product indicates that sea surface temperatures in the inshore areas of the far northern Marine Park are slightly above average.

The United States National Oceanic and Atmospheric Administration (NOAA) uses satellite sea surface temperature monitoring to determine where coral bleaching stress reaches various levels.The National Oceanic and Atmospheric Administration has placed this area on bleaching watch, along with parts of the Torres Strait and the Gulf of Carpentaria.

Sea surface temperatures are also slightly warmer than average in the inshore areas of the southern Marine Park however there is currently no bleaching watch for this area.

In the remainder of the Marine Park, sea surface temperatures are average to below average.  A low level of thermal stress is beginning to accumulate throughout the region, however there is currently no threat of significant thermal bleaching for the majority of the Marine Park.

Crown-of-thorns starfish (COTS) management program

The Reef Joint Field Management Program crown-of-thorns starfish (COTS) response team recently returned from the Whitsundays region where they surveyed eight offshore reefs of high tourism and ecological value.

While there was evidence of crown-of-thorns on some of these reefs, no outbreaks were found.  In addition, while the impacts of Cyclone Debbie (2017) are still visible across these reefs, signs of recovery were observed in some areas.

Monitoring will continue, and our proactive crown-of-thorns starfish control measures will be undertaken if necessary, to prevent potential outbreaks developing on these high value reefs.

Merry Christmas

We will take a short break from reporting on Reef health during the festive season, however conditions will still be closely monitored over this time.

If you are out on the Reef over the holidays, we remind you to stay safe and also make sure that you are familiar with the Marine Park rules, including zoning restrictions. Free zoning maps are available from local bait and tackle shops or visitor information centres, or by downloading the free Eye on the Reef zoning app.

Any suspected illegal activity can be reported to our free 24-hour hotline 1800 380 048 or online – information on how to do this is available on our website.

Anyone can also report interesting sightings or reef health incidents through the Eye on the Reef app, so we can all play a part in keeping an eye on the reef this holiday season.

Our video updates have ceased for the year and will recommence in the New Year.

Weekly Reef health update -  6 December 2019

Temperatures and rainfall

We are now officially at the start of summer. Spring 2019 was officially the fourth driest and the fifth warmest Spring on record for Queensland.

Conditions are hot and dry across the Great Barrier Reef catchment. This is directly due to the low to severe intense heatwaves over the last few days. Heatwaves are expected to continue to affect the region over the coming days.

Sea surface temperatures throughout the Marine Park are average to below average, with no current threat of significant thermal bleaching.

We use a specific tool designed to determine the accumulation of thermal stress in the Marine Park including mapping of Degree Heating Days. Models indicate there appears to be some level of thermal stress beginning to accumulate in some inshore regions from Townsville south and in the inshore to mid-shelf regions from Mackay south.

Forecasting modelling

Forecast tools from the Australian Bureau of Meteorology and United States National Oceanic and Atmospheric Administration indicate some level of thermal stress is likely to be seen throughout the Marine Park by the end of January. Areas to watch for coral bleaching in December and January include the central and southern management regions ( between the Bowen and Gladstone regions).

Reef health

Large suspended algae blooms have been reported via the Eye on the Reef sightings network. This is normal for this time of year and thought to be associated with the annual coral spawning event.

If you witness further algal blooms through the Marine Park, submit the sighting via the Eye on the Reef app or sightings network.

Weekly Reef health update -  29 November 2019

Dr James Kerry, acting Chief Scientist for the Great Barrier Reef Marine Park Authority, presents a pre-summer weekly update on the Reef.

Summer Reef update video may be watched by clicking here -

Pre-summer workshop

Scientists and Reef health managers are not, at this point, expecting to see a marine heatwave or severe mass coral bleaching on the Great Barrier Reef this summer. However, local weather conditions will have a key influence on sea surface temperatures during the summer.

This was a key conclusion from the annual pre-summer workshop convened by the Authority late November to predict potential impacts on the Great Barrier Reef during the highly sensitive summer period.  The workshop brought together scientists, marine and tourism managers, reef managers and experts to look at how the Reef will fare over summer.

A recent media release on the outcome of the workshop is available.

Temperatures

Sea surface temperatures throughout the Marine Park are currently average to slightly above average, with no current threat of significant thermal bleaching.

Forecast tools from our partners at the Australian Bureau of Meteorology indicate that December may bring some thermal stress to the Whitsundays. There may be some thermal stress between Mackay and Rockhampton areas around the inshore to mid-shelf areas.

Crown-of-thorns starfish (COTS) management

The Authority has received Eye on the Reef Sightings reports of crown-of-thorns starfish on several reefs offshore from the Whitsundays. This area is of high importance for the resilience of both coral reefs and reef-based industries.

In response, our Field Management Program will deploy a vessel at the beginning of December to assess reef health and the impacts of crown-of-thorns on these high value reefs in this region.

The data collected will be used to strategically plan any future crown-of-thorns control activities on these reefs.

Outbreaks of crown-of-thorns starfish are ongoing in the central and southern Marine Park, with the most severe outbreaks occurring in the outer parts of the southern region.

Reef health

There have been multiple reports of coral spawning through the Eye on the Reef Sightings Network throughout the Marine Park.

Some localised minor levels of bleaching have been reported, coral disease and coral damage in each management area of the Marine Park.

A giant, filter-feeding whale shark was also reported in the Whitsundays. The timing of this sighting and past sightings indicates that whale shark presence in the Whitsundays aligns with the annual coral spawning, a favoured food source for this majestic animal.

Pre-summer Workshop

15 November 2019

Temperature and rainfall outlook

Sea surface temperatures throughout the Marine Park are currently average to slightly below average, with no threat of significant thermal bleaching. The Australian Bureau of Meteorology daytime temperatures for summer are likely to be warmer than average across Australia, including the Reef catchment, for the remainder of 2019 and into early 2020. The onset of the Australian monsoon season in 2019-2020 is likely to be delayed.

Reef Health Impacts

Reports of coral spawning on offshore reefs within the northern sections of the Marine Park have been received this past week via the Eye on the Reef sightings network.

Summer planning

Planning for the higher risk summer season has commenced, with our annual pre-summer workshop to be held next week in Townsville. The workshop will bring together scientists, managers and key stakeholders to discuss the events of last summer on the Great Barrier Reef and the outlook for the coming summer.

8 November 2019

Temperature and rainfall outlook

Sea surface temperatures throughout the Marine Park are currently around average, with no threat of significant thermal bleaching.

The Australian Bureau of Meteorology forecast warmer and drier than average conditions for the Reef catchment for the remainder of 2019.

In December, sea surface temperatures are likely to be average for most of the Marine Park, except the inner and mid-shelf areas from Mackay southwards (above average) and parts of the Far Northern management area towards the tip of Cape York (slightly cooler).

Reef health impacts

Reports from the Australian Institute of Marine Science and the Eye on the Reef network indicate there are local cases of low level coral bleaching, disease and damage in all regions of the Marine Park, excluding the far northern region which remains to be surveyed. These impacts are within the normal range expected for this time of year.

There are ongoing outbreaks of crown-of-thorns starfish in the central and southern Marine Park. Numbers of the coral eating crown-of-thorns starfish have increased in the Pompey sector and decreased in the Swains areas of the southern Marine Park, according to the Australian Institute of Marine Science.

Five crown-of-thorns starfish control vessels are still working in conjunction with the Australian Institute of Marine Science to conduct plankton sampling throughout the starfish spawning season (November to February), as part of a research project developing the use of eDNA to monitor levels of starfish larvae.

October 2019 update

Temperature and rainfall outlook

Sea surface temperatures throughout the Marine Park are currently around average, with no threat of significant thermal bleaching.

The Australian Bureau of Meteorology forecast warmer than average conditions and less rainfall than usual for the Reef catchment for the remainder of 2019.

Near average sea surface temperatures are predicated for the next two months, except in the southern Marine Park where slightly above average temperatures are expected.

Tropical cyclones

The Australian tropical cyclone season runs from November to April. On average, there’s about four cyclones in or near the Reef each season and one may make landfall.

The Australian Bureau of Meteorology tropical cyclone season outlook for 2019-2020 indicates there’re likely to be less cyclones in this region this season.

Importantly, this forecast does not predict cyclone severity or damage from wind, large waves, storm surges, widespread rainfall and dangerous flooding in the Great Barrier Reef region.

Summer management planning

Preparations are currently underway for our pre-summer workshop, which will be held in November and involve leading reef managers, scientists and experts looking at what might happen over summer.

At this workshop, the previous summer is reviewed along with current conditions, early warning tools and climate outlooks for the upcoming summer to assess the short-term environmental risk for the Reef.

The workshop findings guide preparations for the upcoming summer, including considering risks to Reef-reliant communities and industries.

Eye on the Reef — sightings

Coral spawning was observed a several inshore reef locations throughout the Marine Park this month.

The time of year that corals spawn depends on their location — inshore reefs usually start spawning one to six nights after the full moon in October and outer reefs usually spawn during November or December when ocean temperatures begin to warm towards the start of the Australian summer.

In addition to replenishing the coral cover on coral reefs, the mass coral spawning events also provide a food source for other marine creatures, including plankton and some fish species.

Crown-of-thorns starfish control program

All five crown-of-thorns starfish control vessels are working in conjunction with the Australian Institute of Marine Science to conduct plankton sampling throughout the starfish spawning season (November to February), as part of a research project developing the use of eDNA to monitor levels of starfish larvae.

September 2019 update

Two-week Sea Surface Temperature Anomaly

In the two weeks up to 23 September 2019, sea surface temperatures were slightly below average throughout the Marine Park, except for the southern area where sea surface temperatures were average to slightly above average.

Temperature and rainfall outlook

The Australian Bureau of Meteorology forecast warmer than average conditions and less rainfall than usual for the Reef catchment for the remainder of 2019.

Average sea surface temperatures are predicated for this time, except for in the far northern Marine Park where sea surface temperatures are likely to be slightly cooler than average in October.

Crown-of-thorns starfish control program

We run a crown-of-thorns starfish control program in the Marine Park, involving several control vessels.

One of these control vessels is currently working on three high value tourism reefs in the Capricorn-Bunker Group (southern Marine Park).

On one of these reefs, the team achieved sustainable ecological thresholds of the coral-eating starfish at 18 of the 22 starfish cull sites identified by surveillance.

Surveillance on the other two reefs didn’t find starfish at outbreak levels, however pro-active culling was used to prevent the start of an outbreak.

In the central region of the Marine Park, control vessels are focusing on five reefs showing starfish outbreaks on a scale from potential to severe level thresholds.

In the northern Marine Park, there’s plans to check the Lizard Island area ahead of schedule and in collaboration with researchers. This follows observations presented at the recent National Environmental Science Program workshop.

Eye on the Reef — Sightings

A number of humpback whale sightings were reported through our Sightings Network in September, which is towards the end of their annual migration period, with most heading south back to Antarctica.

Four fruit bats were found at Heron Island in September — it’s a very rare sight to see these bats that far off the coastline, suggesting the animals may be seeking food and refuge.

An egg mass from either a diamond or bigfin squid were recorded in the Marine Park near Mackay Cay out from Cape Tribulation.

These long sausage-like, transparent, floating egg masses are found throughout the world’s tropical and sub-tropical waters, but not commonly captured on video.

August 2019 update

In August 2019, we released our 2019 Outlook Report — it provides a comprehensive summary of Reef health and management, including the future outlook for the Great Barrier Reef (the next five to 25 years).

The Australian and Queensland Governments also released the Reef Water Quality Report Card 2017 and 2018. For the first time, results are reported at a finer catchment and sub-catchment scale.

Climate outlook

Winter 2019 was warmer than average, and one of the driest winters on record for much of Australia.

Predictions indicate Queensland is likely to be warmer and drier than average for the remainder of 2019.

It is also highly likely the Great Barrier Reef catchment, Cape York Peninsula, and coastal parts of Queensland will experience late onset rainfall this season.

Crown-of-thorns Starfish Control Program

One of our crown-of-thorns control vessels completed three voyages to the Capricorn Bunkers group to focus on high value reefs.

The majority of intensive control effort was focused around Lady Musgrave Island, with more than 300 dive hours spent culling over 2000 crown-of-thorns starfish.

While initial surveillance at Lady Elliott Island indicated crown-of-thorns starfish were below outbreak levels, control teams proactively searched and culled at all at-risk sites around the reef in order to prevent the development of an outbreak.

Both of these reefs were assessed as having healthy coral cover.

Raine Island sand re-profiling

Remote Raine Island — home to the world’s largest remaining green turtle nesting population and an important seabird rookery — will undergo the third major sand re-profiling exercise beginning this month as part of the five-year Raine Island Recovery Project.

Eye on the Reef - Sightings

There’s been some anecdotal reports from a local tourism vessel of ‘cold snap’ bleaching occurring at Davies Reef.

A rare and amazing sighting of a whale shark was recently spotted in the Coral Sea and reported through the Eye on the Reef app.

All types of coral reef health reporting are important for identifying current reef conditions — please bring it to our attention through the Eye on the Reef App or sightings network.

July 2019 update

Climate Outlook

August to October is expected to be drier than average across the Great Barrier Reef catchment. Temperatures around the coastal regions south of Cairns are expected to be warmer than average conditions.

Salinity levels

Salinity levels of inshore regions between the tip of Cape York and Townsville (including Princess Charlotte Bay) have returned to near normal levels (34-35parts per thousands), after a prolonged period of below average salinity conditions as a result of the northern wet season.

Crown-of-thorns Starfish Control Program

We received critical field intelligence about outbreaks of the coral-eating starfish at several reefs in the Capricorn Bunkers. We’ve deployed a control vessel to the Capricorn Bunker group to focus on six high value reefs.

Sea Surface Temperatures

As the cooler months set in, July saw colder sea surface temperature from Lockhart River, north of Cooktown, to Rockhampton. It was one degree below average temperature in the Townsville region.  Sea surface temperatures during August are expected to remain cooler than average in the northern and far northern areas of the Marine Park, average in the central regions, and slightly above average for the southern Great Barrier Reef.

Graph above © Bureau of Meteorology

Eye on the Reef / Sightings

Tourism industry data from their regular dive sites continue to show typical winter conditions. These colder water conditions slowed the growth of certain organisms, resulting in reduced macroalgae and coral colony diseases. There’s increasing submissions through our sightings network from tourism operators about crown-of-thorns starfish around the Capricorn Bunkers near Rockhampton, providing early warning data.

And there’s good news too — the stars continue to shine, with several reports of humpback whales and minke whales. There was an interesting sighting t of two white whales travelling north inside Tongue and Batt Reef, offshore from Port Douglas.

Seeing a whale in the Marine Park is a special and memorable experience and, to ensure it happens safely, there are rules in place to protect onlookers and the whales:

• vessels must stay at least 100 metres from whales in the Marine Park
• vessels must stay at least 300 metres in the Whitsunday Whale Protection Area.

Marine monitoring activities

A good news story from the Southern Great Barrier Reef is the recovery of coral on One Tree Island in the Capricorn-Bunkers.  After severe impact from cyclone Hamish in 2009, researchers from Southern Cross University found remarkable recovery of both reef calcification and coral cover to pre-cyclone conditions.

The Australian Institute of Marine Science’s annual Great Barrier Reef Condition Update report shows mixed results for coral cover across the northern, central, and southern regions of the Great Barrier Reef.

Collective disturbances of crown-of-thorns, cyclones and coral bleaching during the last five years caused declines in hard coral cover to moderate levels across much of the Reef.

Graph's above © Australian Institute of Marine Science

June 2019 update

El Niño and Indian Ocean Dipole
The ENSO Outlook remained near El Niño thresholds.  However, climate models suggest a shift away from El Niño in the coming months and moving towards an Indian Ocean Dipole (IOD), bringing warmer and drier than average conditions to much of Australia.

Climate Outlook
July to September is expected to be warmer and drier than average for most of Australia, however northern Queensland is expected to have near average winter conditions.

Salinity levels
Salinity levels of inshore regions between the tip of Cape York and Townsville (including Princess Charlotte Bay) have returned to near normal levels at 34-35psu, following a prolonged period of below average salinity conditions following the northern wet season.

Crown-of-thorns Starfish Control Program
Over the last month, the crown-of-thorns starfish (COTS) control vessels completed management activities at 21 high value coral reefs, culling over 17,500 COTS to protect coral and enhance the resilience of the Reef.

Eye on the Reef sightings network
Over the last month we have seen some interesting sightings submitted through our Eye on the Reef App showcasing the reef’s World Heritage biodiversity values.

The real stars of the show this winter are the whales with the seasonal arrival of the famous Minke Whales. The first report this year came from the Ribbon Reefs. Since then several others have reported experiencing this incredible interaction, at Opal Reef and Flynn Reef in the northern part of the Great Barrier Reef. A particularly exciting sighting was a Brydes Whale feeding between Lady Elliot Island and Lady Musgrave Island in the southern tip of the Great Barrier Reef – a fantastic observation that showcases the whale’s behaviour in the World Heritage Area.

Seeing a whale in the Marine Park is a special and memorable experience and, to ensure it happens safely, there are rules in place to protect onlookers and the whales:

• vessels must stay at least 100 metres from whales in the Marine Park, and
• at least 300 metres in the Whitsunday Whale Protection Area

Marine monitoring program activities
The Authority, Australian Institute of Marine Science and James Cook University continue to conduct monitoring activities throughout the Marine Park. This includes coral monitoring, water quality surveys and seagrass sampling.

Sea surface temperatures
With the onset of winter, sea surface temperatures continue to decrease throughout the Marine Park.  Sea surface temperatures winter forecasts are for slightly below average from Cairns to north of the Marine Park. Average winter conditions remain for the Whitsundays to Capricorn Coast regions and above average winter sea surface temperature’s predicted for the southern regional areas of the Marine Park.

Graph's above © Bureau of Meteorology

May 2019 update

Unseasonal cyclone activity

An out-of-season tropical cyclone, tropical cyclone Ann, approached the far northern area of the Marine Park as a category two system on 12 May, but rapidly weakened to a tropical low before entering the Marine Park and crossing the far north Queensland coast near Lockhart River on 15 May.  The system produced moderate rain falls in far north-eastern Queensland.

Dry season conditions returning

The dry season is returning after out-of-season rainfall across northern Australia.  However warmer than usual conditions are likely to continue across the north, until temperatures across the south of the continent drop significantly.

El Niño and Indian Ocean Dipole

The ENSO Outlook was downgraded in May, with models now predicting a 50 per cent chance of an El Niño developing (down from a 70 per cent chance last month) by mid-2019. While sea surface temperatures are predicted to remain close to El Niño thresholds until mid-winter, water beneath the surface has cooled.  A neutral ENSO state is most likely by October 2019.

Reef monitoring in the Whitsundays

The Australian Institute of Marine Science completed long-term monitoring surveys of the Whitsundays area of the Great Barrier Reef in May 2019.  These are the first surveys of the area since cyclone Debbie in 2017.  Surveys indicate coral cover on two of the reefs surveyed declined slightly since the last survey, which is most likely due to tropical cyclone Debbie. Overall, average coral cover in this area remains at moderate levels (10 to 30 per cent).

Whale season underway

May marks the start of the humpback whale season on the Great Barrier Reef.  From May to September each year, humpback whales come from Antarctic waters to the Great Barrier Reef World Heritage Area to calve and build up strength over the winter before they return to the Antarctic in summer. Sightings of whales or other wildlife can be captured and shared using our Eye on the Reef app.

Summary of 2018-2019 summer

Over the 2018–19 summer we published weekly updates on the health of the Great Barrier Reef as this is a high-risk time for the Reef.

We’ve combined information from those weekly summaries to produce this wrap-up of summer conditions and impacts.

Temperature and sea surface temperature

The El Niño-Southern Oscillation — the weather’s movement between  El Niño and  La Niña conditions — remained neutral but near El Niño levels throughout summer and autumn.

Summer 2018–2019 was the warmest summer on record for Australia.

In Queensland, it was the fourth warmest summer on record in terms of mean temperature. It included the third warmest December, the warmest January on record, and a warmer than average February. The autumn months of March and April were also warmer than average.

Sea surface temperatures were above average throughout the Marine Park for most of summer, peaking through January and February.

However, the cooler regional weather conditions (associated with the monsoon trough and tropical cyclones) reduced sea surface temperatures back to average or slightly below average for several weeks, markedly reducing the accumulation of thermal stress and the associated threat of mass coral bleaching.

Coral bleaching and disease

There was no significant large-scale coral bleaching event in the Marine Park this summer.

Minor bleaching was reported from all management zones in the Marine Park, however these instances were generally at the scale of individual colonies. Low level coral bleaching is normal over the summer months as corals become stressed by warmer ocean temperatures.

In addition, low level coral disease was reported from all management zones in the Marine Park at local to regional scales. Coral disease is a natural part of the system and is often reported at low levels throughout the Marine Park during the summer months.

Rainfall and floods

Rainfall this wet season (October 2018 to April 2019) was strongly influenced by monsoon and cyclone activity.

While rainfall was below average for most of Australia, it was very much above average for large parts of northern Queensland during the summer months and into March and April 2019.

In late January to early February 2019, a monsoon trough and associated low pressure system brought torrential rain to the Townsville region and caused major flooding.

Extensive flood plumes developed along the coast between Bowen and Cooktown, including a major plume from the Burdekin River which extended up to 100 kilometres offshore, reaching mid- to outer-shelf reefs.

Initial results and modelling indicated flood plumes from the combined effect of the monsoon rains, and the heavy rains associated with tropical cyclone Trevor, significantly reduced salinity levels in inshore regions of the Marine Park between Lockhart River and Bowen.

In some areas, lowered salinity levels were recorded as far out as the mid-shelf reefs. Salinity levels subsequently returned to normal in many areas, however as of the end April, salinity levels were still lower than average (for the Great Barrier Reef) in the shallow inshore areas between the tip of Cape York and Townsville.

As of the end of April 2019, surveys of seagrass meadows and inshore coral reefs throughout the flood-plume affected regions had indicated little noticeable change.

Isolated cases of freshwater bleaching on inshore coral reefs in the Townsville regions were reported, however overall coral mortality was low.

Animal strandings and key habitats

As at the end of May 2019, there have been no reported increases in strandings of marine animals reliant on seagrass meadows, such as green turtles or dugongs.

The longer-term impacts on inshore coral reefs and seagrass meadows depends on the duration and degree of exposure of these habitats to flood plumes and reduced salinity.

Monitoring of these habitats in key areas will be ongoing in order to identify any lag effects.

Cyclones

It was an average cyclone season (November to April), with four tropical cyclones affecting the Queensland region – Owen (December), Penny (January), Oma (February) and Trevor (March). In addition, a fifth cyclone, Ann, occurred out of season in mid-May.

Tropical cyclone Trevor and ex-tropical cyclone Penny caused extensive rainfall and flooding of Far Northern river systems, leading to large flood plumes. Some rivers reached their highest flood height on record, and the subsequent flood plumes reached mid-shelf reefs around the Lockhart River region.

Full assessments of coral damage as a result of the five tropical cyclones/tropical lows which affected the Marine Park are pending.

Preliminary cyclone wave damage modelling by the Australian Institute of Marine Science (AIMS) indicates there is likely to be some damage to coral reefs, particularly from tropical cyclone Trevor and ex-tropical cyclone Penny in the far northern part of the Marine Park.

AIMS Long-Term Monitoring Program surveys of far northern reefs in January confirmed signs of storm damage attributable to Penny.

While tropical cyclone Oma did not enter the Marine Park, the winds and swell it generated affected the southern Great Barrier Reef. Wave damage and salt water incursion has been reported from islands and cays in the southern Marine Park.

Crown-of-thorns starfish

Active outbreaks of the coral-eating crown-of-thorns starfish are ongoing on reefs in the Northern, Central and Southern management areas.

The Authority’s recently expanded Crown-of-thorns starfish control program continued targeted, proactive surveillance and culling on reefs of high tourism and ecological value in the Marine Park to reduce (or maintain) the starfish at densities that allow for coral growth.

This includes surveillance and management of crown-of-thorns starfish on high value reefs in the Far Northern management area for the first time in the program’s history.

There’s been multiple significant impacts on the Great Barrier Reef over the last five years, with some of the most significant of those impacts occurring since 2016.

This includes severe cyclones and subsequent flood plumes, outbreaks of coral disease and crown-of-thorns starfish, and an unprecedented two years of back-to-back mass coral bleaching events.

Over this period, most of these impacts were concentrated in the northern two-thirds of the Marine Park.

For the first time in the history of the Australian Institute of Marine Science’s (AIMS) Long-term monitoring program, trends in average hard coral cover on reefs in all three regions showed a decline.

By mid-2018, coral cover in the Region’s north was less than half of what it was in 2013. This was unprecedented and due to mortality caused by two severe cyclones, severe coral bleaching in 2016 and 2017, and ongoing crown‐of‐thorns starfish outbreaks.

The Reef’s scale and natural resilience means it has the capacity to recover from impacts to an extent, given benign environmental conditions and adequate time free from disturbance.

Under a changing climate, recovery capacity is already limited and will be further impaired should the frequency of bleaching events increase as predicted.

Monitoring reef health

We use the best available science contributed by a wide range of research institutions, government agencies, and universities to manage the Reef and ensure it remains healthy for future generations.

There’s a range of programs in place to look at Reef health, including our Reef Integrated Monitoring and Reporting Program, the Reef 2050 Marine Monitoring Program, and the Long-term Monitoring Program by the Australian Institute of Marine Science.

Any long-term impacts on coral reefs will be detected by surveys from these programs.

Because it’s important to have accurate, real-time information on Reef conditions, we work together with our Queensland Government partners and key stakeholders to gather observations of reef health and impacts through the Eye on the Reef program.

Any visitors to the Reef can also report interesting sightings, or observations of coral bleaching, disease, predation or damage through the Eye on the Reef app.

Published every five years, our Outlook Report also provides a holistic view of Reef health and management. The next report will be published in mid-2019.