Diving Thoughts

Marcus Lim, a doctor in Singapore and a well-known underwater photographer died on a rebreather dive on the Seven Skies wreck at Pulau Aur in Malaysia.

Some more information here and here.

The BBC have got a crew filming a natural history series called “Life”. As part of their work they have filmed the courtship rituals of the weedy sea dragon, as well as the male giving birth 2 months later. It’s fantastic footage and you can see it here.

Dense superswarms of krill form in the Southern Ocean and some can stretch for tens of kilometres. Krill are shrimp-like crustaceans such as the Antarctic krill (Euphausia superba).

Scientists have discovered that there are two main types of swarms. The smaller ones may be  up to 50 metres long  and 4 metres deep, with an average density of 10 krill per cubic metre.  These are usually made up of adult krill, which are negatively buoyant. This means they have to swim to keep afloat, which takes up energy and means they need to eat more. But while a swarm offers some protection against predators, it means they are also competing for food, which could be why these adult swarms are not larger or more dense.

The second type of swarms are much bigger and also much denser. These tend to be formed of juvenile krill which are buoyant and so need less energy.

One worrying aspect is the possible impact of overfishing, if most krill in the Southern Ocean are gathered in a few very large superswarms. Fishing fleets can effectively locate these superswarms and by fishing them out could remove the majority of krill living in the ocean, which would have a dramatic effect on other species and the environment.

The next thing scientists may have to look at is why the largest swarms form at night, when the animals would typically be feeding and people had expected them to disperse.

The above photo comes from an article on the BBC’s website.

President Mohamed Nasheed (pictured) of the Maldives and 11 of his ministers held the world’s first underwater cabinet meeting. They were all in diving gear at a depth of 4 metres. It was a PR stunt to raise awareness of global warming which could result in sea level changes that could flood the Maldives and make it uninhabitable. The immediate target is to focus attention on trying to get a better deal at the upcoming climate summit in Copenhagen.

The ministers sat around a horseshoe shaped table at 10am surrounded by fish, and signed an “SOS”  agreement, calling for carbon emission cuts.

The president, already a keen diver, told the BBC that “What do we hope to achieve? We hope not to die. I hope I can live in the Maldives and raise my grandchildren here,”

There is a video of the meeting and an article on the BBC’s website.

Halcyon is recalling certain Eclipse, Evolve, Explorer, Pioneer and CCR35 buoyancy compensator’s (BCDs) manufactured between January, 2006 and September, 2008. In addition, selected Halcyon inflatable devices (Lift Bags, SMBs, DAMs, Surf Shuttles and Diver Lift rafts) may also be affected.

The stainless steel Over Pressure Valve (OPV) spring could become excessively corroded, causing it to fail and the valve to leak. Halcyon have claimed that the defect is limited to a very small percentage of springs used between Jan 2006 and Sep 2008.

According to Halcyon’s website – “Worldwide Halcyon distributors will be initiating a similar inspection and replacement process through their dealer networks. Halcyon Manufacturing, Inc in High Springs Florida will also inspect those BCDs or Inflatables sent directly to our facility, replace the OPV spring if necessary and provide free return shipping to the customer.”

Here are some examples of good springs:

Whereas here’s a bad spring:

You can read more from Halcyon’s website.

My Eclipse is too old to be affected. But instead I’ve got one of those stainless steel inflator valves that insists on sticking open from time to time, which I have to clean up every year.

Some of the relics from Henry VIII’s warship, the Mary Rose, are being shown for the first time. The warship sank in 1545 in the Solent and was raised in 1982. It is now in a drydock in Portsmouth’s historic dockyard. Volunteers are now attempting to raise the final GBP 4 Million that is needed to build a new museum which will allow the relics to be housed much nearer to the ship itself. Currently the Mary Rose museum is near the entrance to the historic dockyard, a long way from the drydock containing the vessel which is near HMS Victory, Nelson’s flagship at Trafalgar.

The Mary Rose itself is currently being sprayed continuously with polyetheylene glycol, which is a was-based solution. This is due to be completed in the next couple of years, and then the ship will be gradually dried.

There is more information on this plus a video on the BBC’s website.

Scientists from Diversitas, an international programme of biodiversity science, have warned of an alarming increase of animal extinctions as a result of threats to biodiversity and ecosystems. In a blog they seem particularly concerned about freshwater species.

At the 6th Conference of Parties to the UN Convention on Biological Diversity in April 2003,  123 world ministers committed to “achieve, by 2010, a significant reduction of the current rate of biodiversity loss at the local, national and regional levels, as a contribution to poverty alleviation and to the benefit of all life on Earth.”  Georgina Mace of Imperial College, London, and Vice-Chair of the international DIVERSITAS programme says that ““We will certainly miss the target for reducing the rate of biodiversity loss by 2010 and therefore also miss the 2015 environmental targets within the U.N. Millennium Development Goals to improve health and livelihoods for the world’s poorest and most vulnerable people”.

The Diversitas programme is organising its second Open Science Conference in Capetown on Oct. 13-16 with 600 experts from around the world.

You can read more here.

In an attempt to highlight the threat of climate change, the government of the Maldives will hold a cabinet meeting underwater. On 17th October, all the cabinet ministers bar one (who has a health problem that precludes diving) will hold a meeting at which they will sign a document calling for global cuts in carbon emissions.

President Nasheed, who is already a diver, will also hold a press conference in the water, although presumably not underwater which might make him a little difficult to hear. Although some might argue that would be a good thing for a politician.

The ministers are being trained at a military base in the Maldives and for the underwater meeting will each be accompanied by an instructor and military escorts.

It certainly sounds an interesting way to highlight the effects of global warming, which are likely to hit the island nation very hard, since the Maldives is on average only 2.3 metres above sea level.

President Nasheed sounds to be a bit of a character. Shortly after his election he made headlines when he talked about creating a sovereign wealth fund to buy up land with a view to relocating the entire country.

You can read more about the underwater cabinet meeting on the BBC’s website, from where the above photo came.

On Thursday evening the Royal Geographical Society – Hong Kong are presenting a lecture by Dr. Gavin Schmidt on NASA’s research into the nature of global warming and consequent climate change. The lecture is apparently going to combine scientific analysis with stunning photography illustrating the effects of climate change.

The talk is at 3F, British Council, 3 Supreme Court Road (this venue is next to Pacific Place, 5 minutes from Admiralty MTR) on Thursday 8th October. There will be a Drinks Reception at 6.30 pm followed by the Lecture at 7.30 pm.

There is more information on the RGS-HK website.

It was a nice day on Saturday, and starting to cool down slightly from the summer highs, so Rita and I headed over to Mui Wo at around midday to hike stages 1 and 2 of the Lantau Trail. Stage 1 starts pretty much from the ferry terminal at Mui Wo but we didn’t spot the actual starting point or the first 500 metre marker post, probably because we had to go to the cashpoint. We ended up picking up the 2nd 500 metre marker post on the South Lantau Road.

Stage 1 goes along the South Lantau Road from Mui Wo to the big campsite and barbecue area at Nam Shan. It’s up a mild slope and is only 2.5km long. Since it was a Public Holiday on Saturday for Mid-Autumn festival there were quite a lot of buses and taxis travelling along the road, but even so it was a pleasant walk with some good views over Mui Wo between the trees.

Stage 2 starts at Nam Shan, and heads relentlessly up Sunset Peak (Tai Tung Shan). Quite a lot of the climb is through woodland and it is not as steep on this side as it is coming the other way from Pak Kung Au. There were quite a few other people on the trail, more than I was expecting since it was still quite warm.

Eventually we broke out of the woodland and, despite the haze, we were treated to some great views of Pui O on one side and Mui Wo on the other. We carried on and between Yi Tung Shan and Sunset Peak there are a number of huts scattered on the grassy slopes. I believe these are owned by Christian groups, presumably ones with fairly fit members as they are nearly 800 metres above sea level.

Sunset Peak itself is 869 metres high, but the path skirts the summit, at around 800 metres before dropping sharply down to Pak Kung Au which is at around 340 metres. Despite the fact that the climb from Mui Wo is almost twice as high, it is certainly a lot more gentle and I was glad we’d done it this way round.

I’ve seen Pak Kung Au variously translated as Great Uncle Valley and Nosy Old Man Valley. It is where the Tung Chung road crosses the line of hills that form the spine of Lantau, on its way to Cheung Sha beach. We followed the old road, which is now disused, down to the beach, then along to the Stoep for a recuperative beverage and an excellent steak.

Time: 12:00 – 16:00
Temperature: 28-30C.
Relative Humidity: 80%