When reading the inshore waters, it’s much easier to recognise the spots where fish may congregate because you can visually see features like surf gutters, shallow reefs and sandbars. However; reading the open and often deep offshore waters can be a lot harder!! You need a combination of intuition and guesswork, and an adequate knowledge of the sea, weather and atmospheric conditions. Without touching on boating safety reasons, these conditions can all have an influence on fish presence and behavior.
It’s usually a good sequence of events that creates superb offshore fishing. Similar to the butterfly effect which metaphors the ‘turbulence from a butterfly’, leading to a chain of events that alters the course of a cyclone; certain conditions can come together to create top fishing. There are many conditions to consider too; such as light conditions, wind and barometric pressure, and water conditions such as clarity, turbulence, temperature and oxygen content. A slight to moderate degree of wind and wave action can be beneficial for offshore fishing because the water turbulence will help dislodge food from any bottom dwelling reefs and rock ledges. This food, which is often made up of small bait fish and juvenile crustaceans, are influenced by the wind and currents into dense concentrations. Surface feeding schools such as striped tuna and frigate mackerel are encouraged by this fresh smorgasbord on offer, which then encourages bigger predatory fish such as yellowfin tuna, marlin and shark to show.
The associated whitewater and wind chop that comes hand in hand with these conditions allow fish to move freely with a reduced risk from predators. These conditions also encourage higher than normal levels of oxygen to be absorbed from the atmosphere. Many surface feeding fish (pelagic) such as mackerel, yellowtail kingfish and marlin are constantly on the move, therefore needing oxygen rich water to keep up with their high energy levels and metabolic rate. Some fish such as snapper and mulloway
have a slower metabolic rate and often browse, rest or drift with the moving water - quite often close to cover, and where they feel most comfortable.
The water colour can determine the temperature of the water, where warm waters are indicated by a rich blue colour and colder waters revealing a greenish tinge. Most fish species
tend to feed under the cover of darkness and even half light. Some species can be attracted by the half light of dawn and dusk where they will move from the dark deep into shallower waters. Pelagic fish on the other hand such as tuna and marlin do not seem affected by the light and can be targeted in the bright
light of day.