In this article of explain an equation derived by Piet Van Rooyen (Diving and Spearfishing in South Africa) back in the 1980’s. I then proceed further to alter it and explain the alteration.

S is success in spearfishing. It is equal to the terms on the right hand side of the = sign. Add those up and it could be possible to predict the success of a spearfisherman with fair accuracy. Imagine if you could predict your success in spearfishing outings – it would take a lot of the hit and miss out of the hunts.

In the equation A is the availability of fish, B - bottom time, C - times down, D - experience, E - marksmanship, F - fish sense, alertness and instinct, and G is luck. These factors all have an influence on a spearo’s success. If we can find out what influences each factor we may be a big step closer to predicting our success, or the lack of it.

A: Availability of Fish

The first term, A, is availability of fish. Getting to know the availability of fish in any area you dive is probably going to have a large influence on your success as a spearo, fish photographer or even if you are just a nature loving freediver.

A - Availability of fish is affected by:

• Good quality reef - often produces good fish but not always – here you need to either discover excellent new reef(undived), or you must know exactly when to visit that reef – find out what makes it fire and go then – normally these times are not extensive i.e. narrow windows of opportunity.

• Previous exploitation reduces the number of residential or semi residential species, and some learn what a spearo is – making them much smarter. On heavily exploited reefs you must be fully aware of conditions that boost success and advanced spearfishing techniques that can enhance performance.

• Thermocline, fish do not like extreme temperatures and fast rising cold water may increase the presence of fish.

• Observation is also important – knowing where and how to look is important. You will also benefit from knowing where and when not to look.

B: Bottom Time

Term B in the equation is bottom time which depends on:

Lung capacity - it is said that we cannot change lung capacity. Well I am not 100 % sure of that. Your diaphragm is the "pump" driver – if you can improve the function of your diaphragm then it is quite possible to increase the amount of air taken in.

Lungs can be compressed by a technique such as packing.

Relaxation is very important – you need to be relaxed, calm and extroverted.

Equipment is also very important – for example switching from thermoplastic to carbon fins you may get an increased depth range of say five meters on you operating depth – typically one can add this five meters onto a 20 m depth thus giving a 25% improvement.

Training improves ones capacity to perform – especially in deep or rough water where greater exertion is required.

C: Number of Dives

Times down or number of dives done (C) depends on:

Water temperature which is one of the single greatest determining factors of a spearo’s success. Factors that influence water temperature include the strength and direction of wind and current, season, air temperature, and in shallow areas swell size(mixing thermocline and upper layers) and tide. Cold water also slows up your work rate and even your mental processes if your body chills.

Fitness obviously affects your dive rate.

Other factors that heavily influence times down include – current, depth and swell and the species of fish being hunted. For some species one dives to the bottom and must wait for 40 seconds while with others one may shoot while still descending.

D: Experience

Factor D is Experience which depends your age and frequency of diving. Whether you get the fish or not depends on how we act on the sea floor or in midwater when a fish show up – certain behaviour and body language will inform the fish of your intentions. Violate these and you will probably not see that fish again. Often in spearfishing you need to get a nice specimen of a certain type of fish to "get on a roll" with that species – all of a sudden you get them regularly while before you never had any success.

E: Accuracy

Marksmanship (E) depends on concentration, visibility and equipment. Snipers did not become snipers by going out into action and learning to shoot by knocking off enemy. Often the great snipers of the wars were farm boys who spend many a day traipsing through the woods or veld with a rifle slung over their shoulder.

To get good at shooting you must shoot and shoot and shoot some more with a good quality gun. You will need to be able to concentrate, control muscles and steer your gun. Also you will need to predict spear trajectories and distance. Judging of a fish’s speed and direction will affect marksmanship.

On occasion you may have to judge the viability of a shot and may purposely take a "poor" shot to permit penetration. Marksmanship is a subject best learned at sea with a good gun after brief review of physical phenomena at play.

Visibility also plays a role – you may need to shoot fish which are out of sight at the time that you pull the trigger. In such conditions you predict their swim route and shoot where you expect the fish to be.

F: Fish Sense

Term F consists of Alertness/instinct/fish sense

Fish sense is a spearo’s instinct that directs him to the fish. There is also a logic component to fish sense - e.g. the crackling of the reef can tell of the structure and hence likelihood of getting fish in that direction. There are techniques you may use to enhance your concentration and peripheral vision. It is even possible to enhance your sixth sense that is capable of alerting you of danger and make you aware of opportunity.

The G-Factor

The final term, G, is the mystical Luck factor

What is luck? It’s defined as "good fortune". So, is Donald Trump lucky? How about Bill Gates?

Do consistently successful people always have good luck? Can one arrange things so as to bring about good luck?

Over the last 17 years I have spearfished and always kept an eye on what influences my success, or the lack of it. I sensed something was missing in Piet van Rooyen’s equation. What factors push some divers far ahead of the pack, what brings "luck"? Having been a keen student of personal development for longer than I have spearfished I had a little insight into what was missing.

To me something was missing in the equation. Having thought about it on an off for 17 years I eventually altered the equation by mixing into each term a powerful factor, M. Mathematically it would look like this:

S = (A + B x C + D + E + F + G)M The whole equation is raised to the power M

M is your Mindset and refers to:

• desire to be successful,

• persistence,

• passion,

• obsession,

• single mindedness.

Leverage

In addition to these we must consider the leverage factor. This is the ability of you, the diver, to achieve efficiently by the use of reason to give you an edge. It is synthesizing a winning combination.

It may involve activities such as doing variable ballast dives to get fish in very deep water or "dry scouting" for a competition using Garmin blue charts; or tapping into local fishermen’s knowledge for a competition and much more.

Gletwyn Rubidge holds four South African spearfishing records and represented SA as Springbok spearfisherman in 2007 in Spain. He is an author, holds a doctorate in analytical chemistry, has done over 1300 dives and spent more than 6000 hours at sea in the last 17 years.

Alternatively you may sit on shore while others dive long and hard (inefficiently) for few fish because you know after that after the wind has blown for two days in a certain direction there will be an ice cold thermocline sending herds of awesome fish onto reefs you know. From your dive records you distilled a model for success and can apply that to future dives.