The Rothery's Tide and Fish Predictor (International)

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This was the first piece of serious equipment I that I ever purchased, which I believe gave me the distinct edge over everyone else. In a nutshell, this hand held, fully waterproofed computer gave me the exact times and days of the month for any year upto 2050 that indicates the best time to go fishing right down to the hour. Now let me tell you before you say " Yeah Right"," Too good to be true" well it is. Any good fisherman will know that the moon has a huge influence on how the fish bite, using this type of data, based with every port and tide time table in the world, a lot of number crunching, its able to accuratly tell you the best peak times to go fishing. Remember those old sayings, "you should have been here last week", or when you get back home someone tells you that the fish are going crazy and biting everything. well now you can be that person.


Picture of the Fishpro Handheld Fishing Computer Picture of the Tide & Fish predictor

Read Neils story below.

Neil Rothery's Story about FishPro and TidePro


Combining Ancient Methodology With Modern Technology

If ever I felt the urge to convert my flies, spinners and jigs into not-so-cheap jewellery, and use my rods for doormat dusters, this had to be the time. It was about 30 years ago and I had risen early on what appeared to be a perfect morning to do a tad of trout fishing. The air was crisp and calm and there was just the faintest mist coming off what appeared to be one of the best looking trout habitats I'd ever seen. So with all the anticipation of kid hoping Santa would bring him a bike for Christmas, I made my way upstream armed with fly and spin gear By mid morning my optimism was more than a bit jaded. The trout were there, but they showed only inquisitive interest in a long list of well presented pedigree flies, and no matter what the speed or action of a lure, they would follow and remain within a couple of tantalising millimetres of it - on some occasions, almost to my wading boots.

By 11 O'clock I was still fishless and had decided to quit before I got any further behind. I was sitting under a tree eating a sanga and contemplating my naval, when a young lad came along with a bobby float and a can of worms, and fished from a rock directly in front of me. When he caught the first nice little rainbow, a belt in the face with a dead calp wouldn't have wiped the stunned look off my dial, but when he caught a second I gathered my gear and tattered pride and headed a bit further upstream. On the first cast, the little celta was latched to a nice rainbow within a metre's retrieve from a log on the far bank. Instead of playing around as they had all morning, they were now seriously feeding, and they continued in that vein for about 45 minutes, whereupon the bite ended as abruptly as it had begun.

This apparently unpredictable behaviour had me baffled for quite some time, until I dusted the cobwebs off an ancient Polynesian fishing calendar that my father had obtained from a professional fisho from somewhere in North Queensland. Although I was very sceptical of this myth or legend in the beginning, the calendar had already proved to be quite accurate for salt-water fishing, but I figured it would be of little use when applied to freshwater. Anyway, the above trip prompted me to run my diary across this Polynesian calendar to compare the results. Not an easy chore considering that extremely accurate past lunar and solar information is a prerequisite to performing this task. Eventually, what I discovered about that particular trip and many others that I'd recorded was not news to the Polynesians. In fact they could have told me 600 years ago, approximately when the best bite would have occurred, and just how good it would have been on any particular day.

The angler never existed who hasn't heard the all too familiar 'You should have been here last week', or even worse 'They started biting just after you left'. It's my guess, that because they fished mainly for sustenance rather than pleasure, the Polynesians tackled, and came to terms with this problem of timing centuries ago. Obviously paddling a heavy canoe in unpredictable shark infested waters for no apparent gain was reason enough to formulate a fishing calendar that would ensure more productive outings.

The secret of their success was not only knowing the phase of the moon (to which they gave names for each of the 28 days), but also its precise position in relation to the locality they intended to fish. They knew the fish were most likely to come on the bite for about an hour or so either side of two predetermined periods - one during the day and the other at night. They were also aware that these Peak Periods did not necessarily coincide with either dawn and dusk (even though these are usually reasonable times) or high and low tides. What they learnt, through observation and perseverance, was that the peak activity periods were triggered around the upper and lower transits of the moon and these times are still recognised by many of today's successful fishermen and hunters, as being the prime times for fish and game to be out and on the prowl.

Although many salt-water anglers may argue that the tides have a greater influence on fish feeding habits than the moon itself, it should be understood that the daily tides are governed by the phases and transit of the moon, and that certain marine phenomena occur with precise regularity during the lunar month and solar/lunar cycle. Even to this day. the scientific reasoning for much of these phenomena is not fully understood. However, many marine biologists now believe that the gravitational pull exerted by the sun and moon (the force Earth's ocean tides) and even very small changes in barometric pressure, are sensed by the fish through their highly sensitive lateral lines and built-in sensory systems. This in turn, effects their feeding habits. For example, many fish species will feed with greater fervour during a spring tide than during a neap tide. A spring tide is the extra high tide that occurs around the new and full moons when, relative to earth, the sun and moon are approximately in a straight line and their gravitational fields pull in the same direction. The reason for this heightened activity cannot be totally reduced to the assumption that the higher tide gives them greater access to food, because many of these fish are reef dwellers and pelagics. This varying gravitational force not only effects the oceans, but also acts equally on freshwater streams, lakes and impoundments. So it would be reasonable to assume that land locked fish sense these forces and changes in atmospheric pressure in the same manner as their salt-water cousins, even though, because of the relative mass to that of the ocean, there is not a perceptible rise and fall in the level of most land locked water bodies.

Although the lives of all mankind are still governed to some extent by a built-in biological clock, the vast majority of us are no longer in-sync with nature by virtue of our lifestyles. People such as farmers, professional fisherman and guides whose lives and livelihood are governed by the natural environment are more aware of this through their daily contact with the natural world than are city dwellers, who by contrast, are locked into an artificial time routine for years on end. Ever since we invented the sun dial, the day for most of us, is governed by solar time, which is the time it takes for the earth to make one complete revolution with respect to the sun (24 hours or one day). Research and observation through the centuries has shown that a natural day for fish and many other animal species, differs significantly from our own. Their biological clock appears to synchronise with lunar time, which is the time taken for the moon to reappear at a given reference point during one complete rotation of the earth - an average of 24 hours and 53 minutes. It is also called a tidal day and explains why our ocean tides are approximately an hour later each day - and consequently most fish, fresh water species included, will feed up to an hour later (in relation to our clock time) each day.

A synodic month is the time taken for the moon to complete one orbit of the earth from west to east and return to the same phase reference point (eg from full moon to full moon). This duration is 29 days 12 hours 44 minutes and 2.8 seconds when measured in solar time. A sidereal month is the time taken for the moon to complete one orbit of the earth and return to the same position in the sky. The elapsed solar time for this to occur is 27 days 7 hours 43 minutes and 11.6 seconds and is the basis of the 28 day Polynesian fishing calendar. The simplified diagram shows the eight distinct phases of the moon which occur in a lunar month as seen from the earth in the southern hemisphere. Also shown (exaggerated for the purpose of explanation) is the effect that the gravitational pull (exerted by the sun and the moon) has on the oceans during the new and full moon and the first and last quarter.

As you may well be aware, piecing all this information together to plan a fishing trip can be a daunting task. Even to do the calculations for just one day, in one location would be laborious enough, let alone having to perform the mathematical gymnastics required to calculate a result for any set of geographic coordinates on earth for the past, present and future. Because my previous employment took me to many different corners of the world, it was necessary for me to
keep a library of paraphernalia for the purpose of cross-referencing a fishing calendar with locality specific solar and lunar information, and as well as being a pain in the proverbial, it also proved to be hard on the pocket.

A combination of the latter problem and a North American blizzard in 1983, was incentive enough for me to begin formulating and writing a computer program that would do the hard yards for me. By 1985 and a couple of near divorces, I had a software package that simply required an input of date, geographic coordinates and time zone and a computer could now calculate more accurately in seconds, all that I could achieve in hours of research and manual computations. Subsequently, my charts relating to this system have become a popular feature of 'Outdoor Life', one of the best sporting magazines in the United States, and over the years, this had resulted in a mountain of requests for a computerised version of them.

Outdoor Computer Systems (OCS) took on this challenge and in 1991 produced a purpose-built, robust, hand-held microcomputer that's as easy to use an ordinary touch telephone. The 'fisherman friendly' Tide and Fish Master (TFM41) microcomputer is the only one of its type in the world. A meld of ancient methodology and modern technology, it was designed to give quick and easy access to a wealth of information that is otherwise most difficult to obtain. This information includes sun, moon, tide times and heights for any locality from 1970 to the year 2050. Adaptable to both freshwater and salt-water fishing, the TFM 41 will compute daily bite times and predictions in accordance with the meticulous observations of ancient Polynesian fisherman.

Since the release of the MK1 Tide And Fish Master, OCS has received a great deal of input from various user groups such as the Navy, Army, marine biologists, professional and amateur fishermen and the yachting fraternity. This long list of wishes and feedback has now culminated in a MK2 version that will be released in Australia in the near future. This unit takes over from where the MK1 left off, and will allow the user to virtually specify his own requirements - even to having his own fish rhythms included if he so desires.

A few of the other major features to select from are. Direct latitude, longitude and time zone input for precise astronomical information and locality specific best fishing times; Extra behavioural rhythms for the different fish species groups; 'Minor' as well as 'major' solar/lunar periods; Identification of days where sunrise or sunset coincide with major or minor feeding peaks, or tides as required; Allowance for user customisation of the time of moon phase and of major and minor peak feeding periods for specific fish species; Civil and nautical twilight times and time of apparent noon. And for those of you who also fish salt-water, the MK2 is capable of producing very accurate tide heights for any given time of the day and will allow the user to produce custom tides for areas not yet listed in tide charts.

As well as helping to put you back in sync with nature's clock, this little computer may also mean the difference between being there when they're 'ON', or being told by some other satisfied angler that you should have been here a couple of hours ago, or for that matter - last week. Also bear in mind that other factors should also be considered when planning a trip. These include local weather conditions, water level and clarity, water temperature, pH levels and so on - and there are very few substitutes for local knowledge, skill and experience. However, if the time you can afford to spend in pursuit of that trophy fish is limited, it's odds on that with one of these computers as a planning tool, your chances will improve considerably, not to mention the potential for saving time and fuel.