COTs - the Underwater Disaster which needs Urgent Action rather than TokTok
COTs SWAT Report #12 : control program underway in Northwest Efate Island; plus use of liveaboards & COTs injection system on GBR.
The last few weeks of May have been relatively busy with COTs culling in the NorthWest Efate area and in trying to locate the new inbound aggregations.
Sailaway Cruises have been mainly collecting new arrivals into our Paul's Rock defence zone. As we are there several times a week with Tourist visitors, when the snorkellers go snorkelling, the Sailaway crew go diving around the perimeter and usually get around 25 COTs in a 1 hour dive (2 flourbags full). If we don't do this, the seamount would soon be over-run with COTs. We removed 180 COTs in a 3 week period in May.
The survivors of one large aggregation of big COTs which we diminished in size a few months ago, moved down into 40 metre waters and out of sight of our patrols (down to 25 metres). We thought we had lost them, but they had rapidly crossed a wide sandy plain and came back up to their preferred depth of around 20 - 25 metres when they located another healthy reef system.
The early white scarring on this reef alerted us for the need of more divers to clean them out rapidly before they ventured any closer to Mangaliliu Village.
So on Saturday 25 May, we had 5 divers doing 2 dives to 25 metres and bagged around 210 COTs minimum. This site, off the *Survivor* men's camp beach, will need another mopping up operation before we can be content that we stopped this particular frontal line of fast-moving COTs heading East. Lat: 17 deg 39.063 South; Long: 168 deg 11.176 East .
OTHER COTs REPORTINGS:
Moso Island still has a steady but slow & well-dispersed movement of COTs moving from NorthEast to SouthWest down the outside of the island, with some also being found on the Havannah Harbour side of the island in shallowish waters. Tourism-sensitive areas are being kept clear of them.
Small Second generation COTs have recently been seen at Malapoa Point, Pango Cove and on the Breakas coastline. These would be descendants of the major infestation in Mele Bay a few years ago. These need to be cleared out before they grow bigger and spawn a Third Generation.
We hear that Mota Lava Island, currently has a major infestation.
A relatively small island like this could be cleaned out of COTs, only by the use of a liveaboard boat with scuba-diving compressor, tanks and a keen bunch of divers. Shallow water COTs could be removed by the Villagers working an area at the same time as the divers. This becomes an expensive Operation and would need external Funding.
The islands in and around Luganville are also under assault from a Second Generation of smaller COTs. At least there are some Scuba Operators there who can help keep healthy reef systems and tourism-sensitive reefs free of COTs damage.
They are seeing small COTs on Tanna, but nothing obvious around Aneityum. It may be a bit cold for them down there.
So, it would appear that most of the islands in the Vanuatu archipelago are experiencing this current COTs outbreak.
Dept of Fisheries are hoping to set up a monitoring system to get info from all the islands to see the extent of the infestation. This would identify which areas need the most immediate assistance to cull as many COTs as possible with Community participations, before the COTs can spawn again in the next summer season.
The Great Barrier Reef Marine Park Authority have been helpful in providing information on the injection system they use to kill COTs on the GBR. They have an effective monitoring system in place and plot which areas are currently infested, impending, recovering or clear of COTs . With over 20,000 square Km of accessible reef systems to monitor, that's quite a job. Tourism Operators work in with the GBRMPA to clear tourism-sensitive reefs and other big live-aboard charter boats, funded by the Aussi Government, are active in removing as many COTs as possible from *feeder reefs*, which are about to feed COTs onto healthy reef systems.
Their injection system used by scuba divers or snorkellers, uses sodium bi sulphate injected 17 times (ie One per leg segment) from a sheep-drench gun and backpack of the liquid *pool acid*.
They are currently working on a One-shot system, which would be much more efficient. It's not ready yet, however.
This system might be good for major aggregations where the critters are spread all over the tops of reefs in shallow waters. However, the COTs we are seeing at 25 metre depths are hiding by day under ledges or plate corals and would still have to be dragged out from their hiding places onto a sandy floor to position them top-side up for injection. This would be too time consuming, as you only have about half an hour dive time at 25 metres.
Below is an inspirational account of how some Funded dive boats are managing major cleanups on the GBR. Courtesy of one of the crew members, but sorry, had to condense for the www.nab.vu website which is not accepting images.
Cheers for now, Peter @ Sailaway
email: sailaway@vanuatu.com.vu
Hello fellow emailers.
As most of you already know I have been off-line kinda, on a vessel named MV Hero, off the North Queensland coast-line east and north of Cairns, for the last 10 days.
It was actually a working trip, I had been hired to live on the vessel for 10 days and audit their Operations and Procedures manual for compliance. I was also tasked with scuba diving with the divers who are tasked with killing the Crown of Thorns Starfish. (Cots) I have been asked by several people how did it go and rather than type this several times, I thought I would do it once and send it off to those who may be or may not be interested. If not, then just delete.
The trip was not as successful as I would have hoped for. The winds along the entire Queensland coast were high and blowing from 30 to 40 knots for about 5 days, which when you are out to sea, is not a good place to be , unless you can tuck in behind a reef which we did for most of the second day at sea.
The winds dropped significantly after that, but very slowly and over a few days and although we got into the water for seven of the 10 days, the dive teams killed 4262 Crown of Thorns. Getting back into the tender and then onto the main vessel was not easy at times, due to winds and wave action. But the old man of the sea managed reasonably well on most occasions. J One had to pull oneself over the side of the tender, which isn’t easy, but I managed to do it sometimes with the help of the younger members of the team.
Food was great, its cooked by the trainees on board, who are also required to perform every other chore on board.
These are street kids to some extent, or have had problems with their parents. They have to make a written application for an interview in order to get a position on the course which runs for 6 months. During that time they are paid a wage of $500 per week, they are taught how to scuba dive, then they go on to do other studies which takes them to Advanced Diver and eventually Instructor level for the rest of the 6 months.
During that period, they are taken out of the school room and put aboard day tripper boats going out to the reef and act as assistant guides until they are considered sufficiently trained and experienced to lead their own groups. Further, (there are 15 kids in each group, and they are divided up into three teams.) Two groups are put aboard the MV Hero, which was the vessel I was aboard and taken out to the reef for a 10 day journey. They are required to do all of the cleaning on the boat, stand night watches, in fact do all the chores on the vessel and in addition, dive two to four times per day killing Cots. (Crown of Thorns starfish). If they only dive twice, in a day they are also required to snorkel dive on the top of the reefs killings Cots for at least 90 minutes.
Each team has a team leader and they are supervised by a Dive Supervisor. There is also a skipper of the boat on board. I knew one of the dive team leaders from when I audited another vessel in 2005 and 06. The other team leader is a 23 yo ex army guy. He was induced by a very lenient Magistrate to join the army at 16 years of age, did three tours of Afghanistan, One in Iraq, and three in Timor. Got hit with shrapnel while in Afghan, which got him pensioned out, but he could look after my back any day while walking down a dark alley. He was a Corporal, and the medic in his Platoon, which was part of the Recognisance unit, which in many ways was just as dangerous as the SAS people experience, and he wants to go back into the army. I think his fiancé has other plans for him though. He spent six months working in three different casualty sections of Cairns, Townsville and Brisbane hospitals and he sure knows his stuff.
The coral reefs we visited are under huge pressure by the Cots. Most, well all six reefs we dived on are severely damaged by the cots and there is very little likelihood that they will recover in the foreseeable future as they are not target reefs which get most of the attention. The reefs we visited are considered feeder reefs. That means that once the Cot has eaten most of the reef which it is on, then it moves to another reef. It was thought for many years that once they had eaten out a reef, they died. Scientists now believe they move on to other reefs. They actually put a tracker onto one of them and watched as it crossed about 6 kilometres of ocean floor to get to another reef. They can move about 20 meters, or 60ft for those in America/Canada reading this, in about an hour. The Target reefs are regularly attacked to kill the Cot because that’s where all the tourists are taken out to see. The feeder reefs are then attacked when it is obvious that the target reefs have far less cots on them. We were looking at the feeder reefs.
Now we are talking about millions of these little critters on the reef. The average sized Cot spawns around 20 to 30 million eggs each , three times in the spawning season. That’s from November to February. Now multiply that by the number of mature Cots on the reefs and you have a very large number. Fortunately only about 8 -12% of the spawn develops into a Cot, but if you do the maths with just say 1 million cots on the reef, which is a very conservative number, multiply it by 180 million spawned eggs, and divide that by 8 to 12% you have a huge number that will actually develop into a cot. Reduce that number by those that are naturally predated upon ( by only five or six predators) it still leaves a large number crawling about eating the coral.
In case you are wondering how we kill the Cot, it is very simple. We drop hand grenades over the reef and when they explode......No we don’t, I was just kidding.
Dry acid (sodium bisulphate) is mixed with sea-water, in a large drum at the rear of the boat by one of the crew.
A coloured dye is then placed into the water with it and it is stirred not shaken.
The liquid is then placed into a plastic container which is attached to the divers belt.
Upon entering the water, the diver then attaches a clear tube which runs from the container, to an injection gun which has a very long barrel.
The poison has a high pH factor which when injected into the Cot changes their internal pH causing them to fall apart. The components of the poison break down swiftly in sea water so it does not harm the reef once it leaves the Cots body. Because the Cot is asexual, ( and has nine anuses) it can reproduce its own parts. Therefore, should a Cot be injected only once, it has the ability to isolate that part, eject it from its body and grow a new part. The cot must be injected up to 15 times in its body in order to ensure a kill. The coloured dye is used in the mixture so that the diver can see whether or not he had penetrated the barrel into the body or through it, when he commences to inject the poison. The Cot is then left to die in the water. It is not removed. Its predators have been known to eat the killed cot, however it has not been identified whether or not the predators were adversely affected.
Moving on:-
Apart from that, the air temperature was around 24 – 26 degrees and sea temp around 24 degrees so the diving was warm, but because of the winds, the seas were stirred up and visibility under water was down to only 5 to 8 meters on most dives.
My diving consisted of getting up around 7.30am to 8am, just as the two teams were leaving on their first dive. Breakfast with the skipper, then examination of the Procedures manual and then the auditing for compliance. Got all that done in two days, but I liked getting up later than the rest so I continued for a few more days around the 8am mark. When the teams came back around 9am, the skipper would have prepared some light refreshments which they consumed on the back deck.
An hour later they were heading off for the second round of Cots killing for the day. I would then join them on that dive and help find the Cots in the coral reefs. I would also look at the trainee divers do see how they were performing underwater. Most of them were excellent divers even though they had only been diving for several months. Its amazing how much they improve so quickly when they are diving that regularly.
My job also required me to test their knowledge of safe procedures and emergency drills. To that end I conducted two verbal exercises about Man overboard and Location of Fire Extinguishes on board and their numbers. Neither exercise was 100% but in a pinch they would have got there.
I then conducted an in-water exercise for lost diver/unconscious diver. At the end of a particular dive, my team leader/corporal, swam off and hid in behind some coral. Upon returning to the tender after surfacing, I declared it an exercise only and told them the team leader was missing. Nothing ever goes to plan, but they managed to find the diver after five minutes of mucking around, get him to the surface and start mouth to mouth on him. They then got him back into the tender, ( not an easy job, with an unconscious person) and back to the hero, where Oxygen was supplied. Reasonable well conducted and I gave it a tick.
So, apart from one little incident, all was good, I enjoyed being in the company of very interesting young people and not so young people, and I thoroughly enjoyed my diving. The young people are being skilled up very effectively and I have no doubt that all will find decent jobs when they complete the course.