DAY 24 – MARCH FOCUS ON NORFOLK ISLAND’S REEF
Doris the morning we rescued her
No March update of our reef would be complete without a chat about Doris and her kind – the green sea turtle, Chelonia mydas. We have other species of turtles in our waters, but the green sea turtle will frequent the lagoonal areas of our coral reef to shelter and forage. Those that we see inside the lagoon tend to be juveniles. In other words, they are the future of their species, and an important piece in their species’ genetic jigsaw puzzle.
We understand little about where they come from and where they go, but I have been logging their presence for the last three years, as have others before me. I have placed a note on the turtle page of this website that says:
I’ve often wondered how many turtles visit Norfolk Island’s main lagoon of Slaughter and Emily Bays and suspect it is more than we think. Below are some images of sightings and the dates. I have many more on file and would be happy to provide these to anyone doing academic research on Norfolk Island’s turtles and their health. You can contact me via this website.
Doris was our own little rescue turtle. She caused quite a stir in our remote Norfolk Island community, with ripples still being felt six months on from her initial rescue. She galvanised a posse of volunteers, united in our disgust that her health had been so compromised by the poor water quality entering our lagoons – a situation that has repeatedly been brought to the attention of the Commonwealth of Australia, and the Administration of Norfolk Island before that, over a period of decades.
I won’t bore you with all the details of her rescue and rehabilitation because they are all written here, in detail, in this blog and in social media with the tag #operationdoris.
Suffice to say, poor water quality led to a sick turtle with soft shell disease, and possibly brevetoxin poisoning caused by ingesting toxic algae. She was emaciated and covered in algal growth. A more pathetic sight I have yet to see.
After four months of TLC, she was released as far away as we could manage from the bay that caused her demise in the first place, on the opposite side of the island. Within less than 48 hours she was back, under her ledge in Emily Bay. And we think we are clever!
Emily Bay when it was known as Turtle Bay (Chapman, 1796, Public Records Office)
Doris’s poor health was sad, especially when you consider that our iconic Emily Bay was originally named Turtle Bay when Lieutenant Philip Gidley King arrived in 1788 – within weeks of the First Fleet arriving and colonising Port Jackson (Sydney).
King wrote in his journal:
At 4 in ye afternoon I went with the people to ye Turtle Bay and turned 3, which we brought here. Every day, at low water, we see three or four lying on ye beach asleep in ye sun, but when it is cloudy they never land. Philip Gidley King, 1788
Green sea turtles are listed under the IUCN Red List as endangered. That listing was made in 2004. Australia has answered the call to help this species by creating a Recovery Plan for Marine Turtles in Australia in 2003, and revising it in 2017, with the species listed under the Commonwealth’s Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act).
We could talk about all the reasons why the species is endangered but I won’t go into them in detail here. Instead, let’s look at the EPBC Act’s requirement for endangered species. It requires:
‘… all recovery plans to identify habitat critical to the survival of the species.’
It goes on to define the ‘habitat critical to the survival of a species’ as, among other things, areas necessary:
‘… for activities such as foraging, breeding or dispersal.’
And:
‘All of the identified “habitat critical to the survival of a species or ecological community” areas will be included in the BIA [Biologically important areas] database.’
When I examined the interactive map of the BIA database, Norfolk Island didn’t rate a mention.
The Recovery Plan describes various threats to turtles, but of particular interest to Norfolk Island are the ‘Acute chemical and terrestrial discharge’ and the ‘Chronic chemical and terrestrial discharge’ threats:
‘Acute terrestrial discharge includes large sediment pulses due to extreme flooding events. These events can cause considerable loss of seagrass habitat due to light limitation that in turn can result in decreased turtle health, starvation, increased stranding and decreased breeding condition. These pulse events may also deliver sudden high contaminant loads to the system. While the event itself may be of short duration, the loss of the seagrass meadows may continue to impact on turtle health for several years.’
And this about the chronic threat:
‘Anthropogenic contaminants can make their way into the marine environment from a wide range of agricultural, industrial and domestic sources, and can have direct impacts on marine turtles and their habitats. While not always fatal, long-term exposure can compromise health and increase vulnerability to other stressors. Some diseases and pathogens are exacerbated by poor water quality.
‘Runoff of nutrients and sediment … can impact water quality, causing changes in light and salinity over coral reefs and seagrass meadows, disease outbreaks, and exposure to biotoxins associated with algal blooms.’
Another reisdent turtle, Honu, showing signs of algal growth
So we have the contiguous area of Emily and Slaughter Bays, which, by the Recovery Plan’s definition, is biologically important in that it is a foraging site, which has serious water quality issues and sediment run off. With regards to the sediment, this has been ameliorated somewhat by the reinstatement of the wetland areas in the World Heriatge area of Kingston. However a media release in the Norfolk Islander on 18 March 2023, said:
On an annual basis and as rainfall events allow, the team will remove introduced plant species and woody weeds from Kingston’s waterways. This will be done with … brush cutters, and where appropriate, mowers and small tractors with slashers, to minimise soil distrubance. A small excavator may be used in the channels.
Much of the vegetation, particularly in the lower reaches of the channels is drain flax (Typha orientalis), which is considered to be indigenous vegetation. It is also culturally significant in that it is used for plaiting and weaving by the Pitcairn settlers’ descendants. Further up the channels are plantings of native shrubs, so I am not sure how much there is by way of introduced plant species in there. I’d be interested to know.
I confess to worrying how these works will affect the channels running through the wetlands, and how much sedimentation running onto the reef will be created as a result. Bear in mind, too, that we have acid sulphate soils in the wetland area that should remain undisturbed at all costs. I appreciate that there is a balance to be had with preserving the archeology of Kingston and the environment, but surely there has to be a better way to solve the conundrum.
As I said in my post a few days ago (Tiptoeing through the government silos), our waters are ‘protected’ under the EPBC Act, the same Act that affords protections to green sea turtles. The water that runs into our bays runs through a World Heritage site, Kingston, is also protected by the EPBC Act. Advice from the Department of Climate Change, Energy, the Environment and Water says that even though little is known about the stocks of turtles on Norfolk Island, we can draw on the management actions in the Recovery Plan, where needed. (See the postscript, below.*)
So why haven’t we?
It strikes me that the EPBC Act, the Department of Climate Change, Energy, the Environment and Water’s self-proclaimed central piece of environmental legislation, which was introduced in 1999, is barely worth the paper it is written on as far as Norfolk Island and its forgotten reef is concerned.
Drain flax, at left (in the wetland area after heavy rain) Norfolk Island
*Postscript
Hannah Taylor wrote to the Department to ask for information about the status of Norfolk Island’s turtles. I thought it would be helpful to provide the exact wording of their response. Here’s the relevant part of it, republished with her permission:
The Recovery Plan recognises Norfolk Island as a known foraging area for green and hawksbill turtles from unknown stocks, and leatherback, flatback and loggerhead turtles likely occur in the area. The threats and associated management actions listed at section 5.3 can be used to inform management actions on Norfolk Island (where relevant). As the turtles in the region are from unknown stocks, specific jurisdictional advice is not provided. (My emphasis in bold.)
When Doris was in rehab, samples were taken to do genetic testing. Very soon we should know which stock she originates from. This will a real step forwards when it comes to knowing more about Norfolk Island’s turtles.
A much healthier Doris just before she was released in mid January 2023 (photo credit H. Taylor)