It often comes as a surprise to some divers when, at some point during our Similan liveaboard trip I update my dive log book.

“Do you still log your dives?”, I am questioned. “Yes I do”, goes my reply. Every trip, 4,000 dives into my career. I am not sure the average dive number when most dive professionals stop logging their dives, having never stopped myself, but at some point unfortunately logging stops. Unfortunately? In my opinion yes, so maybe I need to explain why I still log my dives.

Log Books Essential Similan Liveaboard Kit

SSI dedicate pages of their open water manual to the importance of the Total SSI DiveLog System and what it should be used for, including: tracking continued dive education, tracking number of logged dives and dates of previous dives, recording equipment maintenance schedules, tracking correct weighting, providing contact and emergency contact information, tracking dive profiles for planning multiple dives in a day, providing pre-dive check lists and keeping a history of air consumption. PADI likely emphasise the importance of log books, their just being more expensive.

That’s all the serious stuff, there is also the more personal side to your dive log, like a diary or journal it’s where you record your diving experiences, list the underwater life encountered and swap contact details of dive buddies you meet.

There’s plenty of good reasons for keeping a log book starting out as a new diver but when you are working on a Similan liveaboard, diving the same dive sites every trip, having reached the top of your professional training is logging the repetitive information really necessary, aside from setting a good example to fledgling divers? Well yes, at least for me it is and it’s the repetitive information that’s the clue.

A Citizen Scientist on a Similan Liveaboard

During my time running Similan liveaboards I’ve had several opportunities to dive with some of the world’s leading Manta ray scientists. As well as learning a lot about this charismatic fish species I have also learned a great deal about how scientists go about their research. With elusive, migratory species like Manta rays one of the greatest hurdles a scientist faces is actually getting time to study these animals in the wild over a prolonged period of time.

Now there is some margin for error here as my log book is not just data from known Manta ray dive sites, it includes the typical range of Similan Liveaboard dive sites on a four day rotating schedule. With the odd trip off here and there too. However my log book is 13 years worth of diving in the same region listing every single Manta ray I have encountered.

To me it feels like I have such a golden opportunity to gather data for a cause I care strongly about.

As well as logging Manta data I also record sightings of other key species, many of which are endangered or under the threat of extinction such as all local shark species, turtles, Napoleon wrasse, other types of rays, etc. Of course compiling this data is one thing, but what have I actually done with it.

Shark Decline and CITES Wins

In 2010 I wrote an article that was later published in the Bangkok Post about illegal fishing within the national park. Thankfully not something we see a lot of anymore on a Similan liveaboard. To highlight the effects this fishing was having on local marine life I plotted my shark sightings, season by season, broken down into the species you would expect to see around the islands, Blacktip reef sharks, Whitetip reef sharks, nurse sharks, leopard (Zebra) sharks and Whale sharks.

The results were startling, in just two years since 2006, my shark sightings had fallen by half and within six years I was hardly logging any shark sightings at all.

In 2013 the CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) Conference of the Parties was held in Bangkok. One particular shark conservation group, Shark Savers compiled an extensive evaluation of shark populations in Thailand, comparing the potential value of sharks for tourism, mainly through the booming scuba industry versus the relatively small income generated fishing sharks. Another major concern, also highlighted was the long term effects diminished shark populations would have on the local Thai ocean ecosystems.

It was hoped that presenting a Thailand based study would have more of an impact presented on home turf, so to speak. My log book data was included in this study. The hard work by Shark Savers and other organisations paid off with five species of sharks now included in CITES Appendix II, namely the oceanic whitetip shark (Carcharhinus longimanus), scalloped hammerhead shark (Sphyrna lewini), great hammerhead shark (Sphyrna mokarran), smooth hammerhead shark (Sphyrna zygaena), porbeagle shark (Lamna nasus).

At CITES both Manta rays species were also added to Appendix II, mainly through the diligent, tireless work done by Dr Andrea Marshall and the Marine Megafauna Foundation, the organisation I am extremely proud to be involved with here in Thailand.

Don’t Forget your Log Book

Naturally I am thrilled that data I have collected over the years has been put to good use and I’ll continue to contribute what I can to shark and Manta ray conservation. Despite the compilation of data I simply enjoy logging my dives. Diving the Similans for 13 years now constitutes a large portion of my life and it nice to have so much of it documented.

I got the idea of this blog from Kippum, one of my star advanced open water students on MV Hallelujah trip 9. Her log book is great, super neat and detailed and enhanced with simple sketches of notable features of the dive. Thanks Kippum and everyone else on that trip. Here’s the group photo, plus a few other photos from our trip courtesy of Tsuyoki.

Please feel free to comment below, especially if you can included a snap shot of you log book 🙂