BASS FEEDING BEHAVIOUR

Text: Mike Ladle         Lead image: Henry Gilbey (http://www.henry-gilbey.com)

In order to successfully target bass with lures and flies it is essential to gain a detailed understanding their feeding behaviour.

The southern and western coasts of the British Isles are almost at the northern limit of distribution of bass although this is slowly changing due to global warming.  Bass in this area are slow-growing and large specimens of 10-pounds weight are typically over 20 years old. Bass are an active fast swimming fish, passing a great deal of time in the shoal water of reefs and estuaries. At high water they are often found between tide marks within a few feet of the seashore. These fish can be large and wary so targeting them requires a stealthy approach. Placing baits in the shallows and waiting for the tide to flood in over them is a sound strategy. Casting at big fish cruising the margins will inevitably scare them off.

A little known study by scientist D.B.Carlisle gives a glimmer of insight into the way that bass sometimes behave and, because of this, is of extreme interest to anglers. Carlisle spent many hours observing fish by means of underwater swimming on and around an intertidal reef in South Devon. The reef was inhabited, when the tide was in, by two large bass and seven average-sized thick lipped grey mullet. The same nine fish came onto the reef each day and were recognisable as individuals by their characteristic scars and damaged fins.

Bass 1

When the tide began to rise, all the fish, bass and mullet, arrived on the reef as soon as the water was deep enough for them to swim (six to nine inches deep). Whether the water was calm or rough the fish came in and they would even swim in with the breaking waves. The two bass came and went individually but the mullet arrived and left as a school. The fish left the reef when the water was still deep, about one hour after high tide as soon as the ebb current began to run strongly. Whilst they were on the reef each of the fish kept to its own area. The territories of the mullet overlapped with those of the bass but the two species took no notice of one another. The two bass, however, rarely encroached on each other’s area.

Bass 2

When undisturbed, the bass lurked in gullies or around the waving fronds of wrack, waiting to pounce out upon passing sand eels or to take shrimps moving on the sandy patches. When a bass was chasing food it kept all of its fins close to the body until the last instant, when they were spread to act as brakes as the fish turned to seize its prey. In contrast, if a `strange’ bass entered the territory of one of the residents it was driven off by the owner, which `attacked’ with fins spread and mouth agape, in characteristic threat display.

In this case, at least, the bass were available on intertidal rocks and feeding, even in very shallow water, on most of the flood tide. Since they clocked out an hour after high water, a cessation of bites would be expected then. Also, after catching one or two good bass in the area it would clearly have paid to move on along the beach and fish the next territory, and so on.

Small bass may be found inshore in the south of England throughout most years. The larger fish arrive in spring, essentially for spawning, which takes place in the month of May. Spawning occurs on shallow reefs subject to fast tidal currents, or in shallow estuaries. (Since this was written the information on bass spawning has been much improved. The fish spawn as they return from their overwintering areas in the south west starting in March in the western English Channel and continuing until June in the southern North Sea and off north Wales).

Bass can adapt without much difficulty to fresh water, but do not usually ascend estuaries beyond the point where crabs and shrimps are abundant. In the autumn and winter large bass tend to leave the vicinity of the shore when the sea temperatures fall from about 13°C to 9°C. On the Irish coast this is in October-November and they return in late April. In Poole Harbour large (double-figure) bass are occasionally taken by commercial gill netters as early as February and March. Sea temperatures are probably the main factor affecting the seasonal migration of bass.

trophy bass and captor

 Above : Mike with a double digit bass

Research has shown that small bass tend to eat shrimps, prawns and ragworm while larger bass mainly concentrated on crabs and fish. The stomach contents of the larger bass are predominantly shore crabs and, less often, swimming crabs. The latter are not the large, red-eyed, purple-clawed velvet swimmers but the smaller species that live offshore on sandy patches.

The types of fish typically eaten by bass can be classified ‘long thin fish’ namely pipe-fish, fifteen-spined sticklebacks, eels, blennies, rocklings, gobies and dragonets and, occasionally, sand eels. Rarely are sand smelts or young mullet found in the gut contents, even though the two latter species were conspicuously abundant in and around the area inhabited by bass.

maggots 2

Bass often feed on the maggots of seaweed flies and if there is a proliferation of maggots in the water then bass will often feed exclusively on them. The maggots are generated in piles of rotting weed cast up near the high water mark. At high water spring tides the maggots wash out of the weed and drift on the surface of the sea. Bass tend to feed on both maggots which are swirling about beneath the surface and on surface floaters. It seems that once a maggot stops wiggling it loses its appeal to bass. Often bass will be feeding on maggots alongside mullet. Mullet will often cruise along inhaling maggots with their mouths exposed whereas bass tend to swirl and splash going doing beneath mouthfuls. Keep an eye out for surface disturbances in close as the fish will be feeding hard up against the weed. It is possible to target bass with maggot flies provided they look realistic and wriggle enticingly in the water.  VIDEO – TYING THE MAGGOT FLY

The same goes for large brown woodlice (Idothea). If woodlice are readily available then bass will often feed on nothing else.

Just like fly fishermen who are conditioned to “match the hatch”, bass anglers need to take time when they first get to a fishing spot to try and determine what the bass may be feeding on. Scour the margins to see if maggots and woodlice are present. Every bass angler should get used to kicking over heaps of old seaweed and inspecting them for wriggling maggots. Scan the shallows to see if bass are feeding and if not, proceed with care as they may well be there and much closer to the shore than you think.

 

 

One thought on “BASS FEEDING BEHAVIOUR

  1. 32-33 feet is the reasonable deepest level at which most anglers target their “clear” fresh water quarry. The term Clear Water is subjective to where you fish. But for our purposes clear water is when a white lure disappears when dropped overboard at about 16-17 feet. Note again that in this example that 16 -17 feet is the Littoral Zone. That 32-foot marker depth is also where direct, penetrating light diminishes greatly (but not completely). Those 32 feet down from the surface represents where Thermoclines set up shallower and progress deeper; reaching their average deepest point in our examples clear water column during the height of summer.
    From the surface, down, the first 16-17 feet of water, or the average depth at which weeds bottom out mid lake in clear water (again a light penetration condition) is scientifically known as the Littoral Zone mentioned earlier and the most productive, most overall stable layer of water for fishing; season to season. While influenced by natures influx of elements to momentarily change this statement, this layer is stable in terms of water temperature and the early signs of fish reaction to the essentials for life. As lake water becomes stained all reactions appear shallower. Also keep in mind that different species of fish have even deeper and/or shallower ways of living and reacting.
    Some weeds grow deeper or shallower depending on how, where, and when– Lake Specific – photosynthesis can occur. Photosynthesis can occur deeper than the Littoral Zone, but the deeper photosynthesis, thereby dissolved oxygen process is more plankton related rather than weeds. Depending on light penetration, various forms of plankton and their associated oxygen production and transport can sink from near the surface to beneath the thermocline as well as move laterally due to current and wind.

    Biologists have observed underwater fish movements during cold front weather exchanges. The result is and always will be open to doubt. The reason for this involves The Universal Law of Large Numbers. That law states: To get an accurate or finite picture of the outcome, you must first have a very large number of test cases which are the same in detail to draw information from (thousands). Unfortunately, biologists can only measure a few fish at a time, one body of water at a time, and one location within that one lake; precision or anything near it cannot be achieved (please refer to Matt Straws comment on this near the last page of this seminar). For our practical on the water purposes, it’s safe to say active to inactive fish during cold front conditions is likely no better than 50/50. But what we can conclude for sure is the known movement of predator / prey relationships coupled with associated light penetration.

    Active fish, all fish will not feed at the same time. Some fish are full of food “in the moment”. Fish are in fact responding to natural urges, earliest formed instincts, coupled with experience, determining where they can be located during and around such times? While some fish may be digesting a full meal, with few exceptions, given the slam dunk opportunity, hungry, healthy, and eager fish, like all other opportunistic predators, eat/strike, lean toward becoming foodies at times and in some places.

    There should be very few practicing anglers among us that don’t know the effects of an approaching cold front. Just to make it crystal clear to everyone, here’s a short version of all the goings-on.

    Personal Notes:

    Just before the front is upon us the sky is usually clear and bright. Then suddenly, air pressure changes. If we are quite enough, attentive enough, we can feel the change in the pressure on our ear drums just like it happens when

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