Ragworm explained

by Steve Walker

Steve Walker takes a close look at Ragworm, one of the most effective, most available and most frightening sea fishing baits.

Ragworm are among the most common marine organisms and belong to the phylum annelida family of invertebrates. More than 9000 species of annelids exist worldwide, with more than 8000, including ragworm, falling into the class of polychaetes or bristle worms. Polychaetes have bodies with distinct segments, the majority of which have a pair of paddle-like flaps called parapodia with tiny bristles called chetae. The parapodia are used for movement and in some cases they are modified for respiration.

the head and pincers of a ragworm close up a handful of ragworm

There are three main polychaetes’ life strategies: sessile; burrowing; and free moving. Sessile worms fix themselves to hard surfaces and remain in that position for life. Then we have sand burrowing worms like lugworm, which can also swim. And finally, free moving worms such as ragworm, which also burrow. The three species ragworms of main interest to UK anglers for use as bait are the large king ragworm (nereis virens), common red ragworm (nereis diversicolor), and the smaller harbour rag (hediste diversicolor).

Common ‘red’ ragworm

These grow to around 15cm in length and are often found large colonies around harbours and estuaries. Either wild dug or farm-reared, this is the worm that most tackle shops sell as ragworm. Shop-bought ragworm are normally sold by weight, and supplied in newspaper or boxes with peat or vermiculite.

Harbour ragworm

Also known as maddies, mudworm or wrigglers, harbours grow to around 8cm in length, and are nearly always found in healthy colonies. This worm lives in a vertical burrow and populations can reach high densities in sheltered estuaries where conditions are unsuitable for other worm species. This worm is an important food source for many estuarine wading birds, and easily identified by a red dorsal blood vein that runs down the centre of its body. The ragworm is both scavenger and predator. Feeding largely on mud, detritus, and plankton, it can also rapidly shoot out its powerful jaws to fatally grab other soft-bodied animals. Ragworms also catch microscopic phytoplankton by spinning mucus nets across their burrow entrances.

King ragworm

the pincers of a ragworm close upKing rag or ‘Kings’ average 30cm long but are known to reach as much as a metre in length. If you look carefully at the head of a king rag there are two pairs of eyes and four pairs of antennae. Like the common rag, there is also the retractable proboscis famously containing a wicked set of nipping pincers… so, watch your fingers.

King rag are generally dug individually and it is rare to find concentrated colonies of the biggest specimens. Colours range from browny green to bright red/orange, or brilliant red/pink in colour.

During spawning male ragworms change to a light green colour, while females take on a darker bottle green appearance. Males leave their burrows to breed and swarm over the sea bed on a high tide, releasing their sperm. At the same time the females release eggs from the entrance to their burrows and fertilisation occurs. Fertilisation differs between species, but ordinarily occurs en masse, and is dependent upon water temperature and a full or new moon.

bait digger in mud with several ragworm bait digger looking through a fork handle
After breeding the spent ragworms die. Ragworm larva become planktonic, eventually settling on the sea bed where they burrow and grow.

Digging your own

Common ragworm favour broken, moderately muddy or sandy ground of the type found in sheltered estuaries and harbours, and they often populate mussel beds. Find a suitable harbour or estuary, preferably on a big low tide, and identify firm areas of the types of ground described. Be careful in harbours where the mud is thick, black and oozy. These are not fantastic ragworm holding areas generally, and you will certainly get stuck wearing only Wellingtons, while there is a real danger of getting bogged down to the waist even in chest waders.

a wide and narrow tinned forks for bait digging

Watch the ground as you walk across and look for ‘sign’. In an area where there is a large ragworm population foot pressure will force water to the surface through small holes that mark burrow entrances. Also, turn over any rocks or stones and you should reveal the holes and groves that ragworm make. If you are careful and turn the stone over quickly you can sometimes grab the odd ragworm by hand before it disappears down its burrow. If the ground is hard and compact with few buried boulders, a flat tined potato fork is ideal, and there is less chance of cutting the worm with a fork. If the ground is particularly stony, then a narrower tined fork is the better tool. The ground where I dig locally is uncharacteristically soft and surface water often runs in and floods the hole. Therefore I use a trenching spade, and make use of a small baling bucket. In this instance I can dig a lot deeper and quicker with a spade. Whatever your implement, it needs to be strong with a good handle because it will be used as a lever just as much as a digging tool. My local harbour is full of broken spades, and discarded fork heads.

bait digger in mud for ragworm

Rock ‘n’ hole

King rag happily live in very rocky ground where they can exist more or less undisturbed and grow large. Extracting a worm intact from this type of terrain is difficult but not impossible. Kings can often be dug individually by looking for telltale large ‘dimple’ holes on the surface. Again foot pressure can often result a betraying spurt of water, and sometimes you see bits of seaweed wedged in the worm hole that the rag has tried to take. Dig a small trench at the side of the hole/burrow and then try to follow the hole as it winds downward. This is hard work but can produce some massive worms. After exposing a ragworm try to lift it out of the hole with the next dig rather than immediately trying to pull it out… panic or impatience very often only results in a snapped worm. Harbour rag can usually be found in the top 30cm with the bigger worms just that bit deeper… up to 70cm down in some cases. If you find a good location where there are lots of worms you can trench them by opening a dig perhaps four or five spits wide and working backwards through a productive area. Often however, efficient digging involves moving from spot to spot, and turning over small patches of likely looking ground.

bait digger draining water bait digger throwing mud

On big tides start at the furthest exposed point, leaving the top of the beach for neap tides. Bait is often easier to dig right on the edge of the ebbing tide when the ground is still wet and the worms are nearer the surface. As the tide recedes further, the worms go deeper. Conversely, worms instinctively know when the tide is flooding and move upwards in anticipation of a supply of fresh seawater. In this case try digging right on the edge of the flooding tide. Instances of extreme high pressure and warm weather, when the wet ground starts to steam under a hot sun, usually bring the worms up closer to the surface.

Very cold, frosty weather (particularly the first biting frosts of winter) will drive the worms much deeper. Once you have a sufficient supply of worms you will certainly have a mixture of whole and damaged worms. Get yourself cleaned up in a rock pool or somewhere suitable and then clean all of the mud and detritus out of the worm bucket. Fill your main container full of seawater, rinse the worms out thoroughly, and separate the broken ones into a second container.

close up of a ragworm being lifted from sand ragworm from below

This is where my smaller bucket for baling out has a second function, taking all of the broken worms and it fits inside the bigger bucket. Do not leave the shore with whole and cut worms mixed in the same bucket. Body fluids from the cut worms will quickly contaminate the water and ruin the good worms, especially on a hot day if it’s a long drive home.

Cold and dark

My worms live in a fridge in my garage, where I take the time to look after them to make sure they remain in good condition after the effort of digging. As soon as I get home after bait digging whole worms go into a bucket of clean sea water and are aerated via an air pump for a few hours, this gives the worms time to expel any mud that is still in their system. Worms are then taken out and inspected.

a tray of ragworm in the firdgeThe good quality whole worms are divided into shallow trays containing just a few millimetres of sea water. To ensure longevity, it is important not to overcrowd the worms. Trays are covered with a sheet of Perspex to prevent escapes. Broken worms are segregated into a separate tray, while any other slightly damaged worms are set aside in another specific tray. Not only does a bait fridge keep worms cold, but it also keeps them dark. Worms last much longer if kept in a dark environment. If you don’t have a fridge, put them into shallow trays on the garage or shed floor and cover them with something which keeps the light out. As long as they are not overcrowded they will last for several days even in summer weather providing the water is changed regularly. No matter what your storage method the rag should be checked regularly and the water changed if there is any sign of discolouration. It’s important to ensure that the fresh seawater is at the same temperature as the storage area as worms will normally violently react to being placed in water at a high temperature which increases the risk of causalities. If you need to buy your worms from a shop, ask to see them first to make sure that they are in good condition and of a suitable size. There is no point in paying money and going fishing only to find that your bait is no good when you get there. When it is time to go out fishing I wrap my bait in newspaper, which draws the wetness from the worm and reveals their vivid red colour. This also makes them easier to handle. Worms are then placed in a bucket or cool box for transporting to and from the fishing venue. On warm days I also place a frozen cool block in the container. Damaged worms are used first in conjunction with any whole worms if necessary, depending on the size of the baits needed.

Rags to fish riches

Ragworm make a great bait in clear water conditions. It will take most UK species but some are more partial than others. Coalfish, flatfish, pollack, wrasse and cod can be actively targeted with rag, while others might be regarded as more of a fluke.

a flounder taken on ragworm baited spoon a hook baited with a section of ragworm

Rag is an effective float fishing or free-lining bait for pollack, wrasse, and coalfish around S.W. Scotland where I regularly fish, but it nearly always produces the smaller fish, especially where pollack are concerned. My normal method is to head-hook a suitable medium-sized worm on a 2/0 Mustad Viking hook so that it wriggles attractively.

a ragworm and mackerel cocktailWhen boat fishing for pollack, a slowly retrieved medium to large rag on a long flowing trace can be particularly effective. A bunch of wriggly harbour rag on a size 2 Aberdeen can produce flounders every cast when nothing else will tempt them, and the forgotten art of the baited spoon will take flounders, eels, and even mullet when those around you remain fishless. Thread one or more worms up the shank of the hook, and top off with a smaller worm just hooked through the head so that it wriggles about enticingly. This will induce bites from many species such as flatties, whiting, pouting, and small bass.

Although ragworm takes many species by itself, it is often more effective as cocktail bait. Tip off with a little piece of mackerel or squid, whiteworm, peeler or mussel and it can be twice as productive. Sandeel and ragworm together is particularly successful for dogfish and some ray species in certain locations. Remember to match the size of bait and hook to the expected species. The ‘Aberdeen’ hook is the classic worm hook. Choose something like a Viking hook when targeting bigger fish. A small mackerel or squid tippet will stop the bait sliding down and clogging the point of the hook. You can also lightly whip worms on with a minimal amount of elastic thread.

Facebook Comments Box

You may also like

Leave a Comment

I accept the Privacy Policy

This site uses Akismet to reduce spam. Learn how your comment data is processed.