I held the trigger and pierced the fragile skin with the sharp muzzle. And then I shot searing vinegar into the soft body.
I was with a group of 15 divers recently at Tioman island in Pahang. We were armed with special "guns" to kill marine pests known as crown-of-thorns, multiple-armed starfish with venomous spikes, which eat through coral reefs.
We were part of an environmental project by Royal Bank of Canada (RBC) employees and Reef Check Malaysia.
The crown-of-thorns occur naturally in these waters, but they did not seriously threaten coral reefs before.
"This was because they had natural predators such as the Napoleon wrasse (fish) and the Trumpet triton (shellfish)," explained Reef Check Malaysia programme manager Alvin Chelliah.
But these same predators, which are sold as expensive seafood and souvenirs (tritons have beautiful shells) respectively, have been voraciously collected by humans.
With a lack of predators, the crown-of-thorns have flourished, leaving trails of destruction in reefs. The only way out is for scuba sheriffs like us to shoot out the bad guys - we put down 38 of them in one dive.
Meanwhile, another 25 RBC employees, who were non-divers, were also busy - above the water. They were cutting and coaxing rolls of wire mesh into large recyling "bins" for cans and bottles.
On the second day of the project, we divers had two tasks: to "plant" corals, and to install a "buoy line".
For our first task, we had to attach small coral fragments onto special PVC pipe frames. But first, we had to scour underwater for small pieces of living coral which had been (naturally) detached from reefs.
Next, we had to carefully remove a layer of slime and algae which had grown on the frame. Only then could we attach the coral bits with plastic cable ties.
However, things were not so simple. I found that I couldn't get to many of the best coral fragments as they were lodged in between the sharp needles of sea urchins. And those who were cleaning the frame were stung by some mysterious tiny organisms.
Luckily, the second task of installing a rope (held up by a series of buoys) proved much easier.
The idea was to protect one of the most vibrant corals in Tioman known as Pirate Reef.
When we dived in here, there were swarms of small fish - damsels and fusiliers - and extensive "fields" of living corals.
However, according to Alvin, this reef is not well marked and some visiting yachts have dropped their anchors here, damaging the corals. It was hoped that our new buoy line would be something for yachties to moor their boats to, instead of anchoring.
While we did all this underwater, the non-divers helped to install grease traps at three eateries in Tekek, the main village in Tioman.
Such traps collect oil before it can flow into the sea and pollute it. While they are normally a licensing condition by town councils for restaurants on the mainland, somehow this had not been implemented on the island.
Those who had worked on the recycling bins the day before had an even harder task next. They had to crush and flatten some 3,000 plastic water bottles and metal cans - with their feet - so that all of it could be easily shipped over to a recycling agent at Mersing on the mainland.
"It was tough work, and some of the bottles were smelly!" said Tham Yee Leng, who headed the staff programme via their in-house corporate citizenship committee.
Needless to say, disposable water bottles are a huge problem on islands - if only all resorts on Tioman could have water stations for guests to refill their own bottles.
They could even make this a branding opportunity by providing (or selling) durable (plastic or metal) bottles with resort logos.
The staff also waded into mangroves for a harvest of rubbish. Apart from the usual loads of plastic and styrofoam, fishing nets also had to be slowly disentangled from roots and branches.
And the volunteers even picked up a pair of jeans! All in, some 200kg of rubbish were collected.
How to do CSR
This was the third year that RBC employees had come to Tioman to do conservation work. The programme was for 40 employees and paid for by the bank, and apparently it was very popular.
"There were many more staff who wanted to join in," explained Tham. "So staff had to draw lots to see who could come."
The event was part of the RBC Blue Water Project, a 10-year global commitment to help improve the quality of drinkable, swimmable and fishable water.
Clean water is something natural for the bank to get involved in, given one piece of trivia.
"Did you know that Canada has the largest amount of freshwater in the world?" Don Fisher, the RBC human resources chief, asked us over dinner. "One of my hobbies is canoeing. We have so many pristine lakes in Canada," he explained.
But fun events like this one at Tioman are just a small part of the story. When it comes to CSR (corporate social responsibility) programmes, some companies prefer one-off events that may look good for the media or company magazine.
But what is more important is long-term commitment and RBC has been supporting Reef Check Malaysia's programmes for the third year running.
As Alvin explained, "Replanting corals is a long and expensive process which you have experienced. But it's no use if the reefs keep on getting damaged.
"Similarly, it's pointless to do clean-ups if local people keep on throwing rubbish," he added.
"So we need to address the root causes. And that's why we are thankful to RBC for funding our programmes. The real work is to create awareness to convince locals to conserve reefs."
To that end, Reef Check Malaysia has been working on Tioman for the past three years to train island residents to become snorkel eco-guides, to set up mooring buoys and to do recycling, among other things.
In the meantime, we were all happy to have done our bit for marine conservation on one of Malaysia's most beautiful islands.
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