Understanding Tides

The tide has a massive influence on sea fishing. Some marks fish better on certain tides, whereas others are inaccessible or even dangerous at during some tides. Although anglers will never be able to fully predict the way fish react to the different tides, some understanding of how marks fish over different tides can increase catch rates dramatically and cut down on the number of blank fishing sessions. The problem with understanding tides is that there is so much regional variation between places, venues and marks that it is impossible to come up with any hard and fast rules over tides. Like many things in fishing, local knowledge is best when it comes to trying to understand how tides influence fishing at any particular mark.

Ebbing Tide, Monreith Beach
The ebbing tide at Monreith Beach, Dumfries and Galloway.

Understanding Tides

Tides are caused by the moon, sun and rotation of the earth working to cause sea levels to rise and fall. The UK has semi-diurnal tides, meaning there are two high tides and two low tides twice a day (some parts of the world have diurnal tides meaning there is only one high tide and one low tide each day). Tides work in cycles and the exact time the high tide and low tide points occur changes every day. For example, the following shows how the tide times move on every day in Blackpool in Lancashire.

Wednesday 8th August 2012

  • High Tide 03:25
  • Low Tide 10:02
  • High Tide 15:45
  • Low Tide 22:16

Thursday 9th August

  • High Tide 04:07
  • Low Tide 10:35
  • High Tide 16:30
  • Low Tide 22:57

Friday 10th August

  • High Tide 04:07
  • Low Tide 10:35
  • High Tide 16:30
  • Low Tide 22:57
From this we can see how the exact times of high tide and low tide occur at a later time every day as the tide cycle progresses. This is the same for every location in the UK, although the exact amount of time between tides will differ from place to place. In some locations, the time of the tides moves along by well over an hour every day, whereas in others the tides may take place only a short time later every day.

Who is Responsible for Gathering the Information on Tides?

Information on tides in the UK comes from the National Tidal and Sea Level Facility which was set up specifically to provide high-quality information on tides, sea levels, flood warnings and issues that affect navigation at sea. Tide levels are calculated and monitored by the UK Tide Gauge Network which has forty-five gauges around the coastline of Britain which gather, process and calculate tidal information. These gauges provide the local scale which is used in the public information on tides and tidal levels.

Spring and Neap Tides

Spring tides are the biggest tides, caused by the gravitational pull of the moon being particularly strong. During a spring tide, the water level will rise to its highest possible point at high tide, and at low tide the level will be at the lowest possible point. When anglers talk of there being a “big tide” they are referring to a spring tide occurring. The tidal flow during a spring tide will be very strong due to the large amount of water which is flowing. Spring tides happen every two weeks during the time of a full moon. Neap tides also happen every two weeks during the period of the first and third quarter of the moon (in the weeks in between spring tides). During a neap tide the high tide will not come up particularly high, and the low tide will not be particularly low, and the strength of the tide is likely to be fairly weak. We can also use Blackpool as an example again to see the difference between spring tides and neap tides: on a spring tide the high tide level can reach 9.1 metres on the local scale, and low tide is down to 0.7 metres. On a neap tide high tide only reaches 6.9 metres, and low tide is 2.8 metres.

Tidal Range
Diagram showing the difference in high tide and low tide levels during spring and neap tides.

The term spring tide, therefore, has nothing to do with the season of spring, and spring tides happen all year round. During a spring tide, anglers are most likely to have trouble keeping weights anchored to the seabed, and some marks can become unfishable due to the power of the tidal flow during a spring tide but these marks can be perfectly fine to fish during a neap tide. Information about tides can be gained from the local press, or from the link on this page. Most fishing tackle shops will also sell booklets for a reasonable price (usually around £1) which provide tide tables for the forthcoming year.

Tidal Flow

The tide will play a big role in the type of weight that is chosen. A sandy beach with a weak tide would be ideal to use a plain weight as the low strength of the tide will push the weight around and allow it to (hopefully) roll into a fish-holding gully or other feature which holds food and therefore attracts fish. However, in a rocky venue with a strong tide it would be better to use a grip lead as allowing the weight to roll around would see it inevitably roll into a crevice or crack and get snagged. At many venues the tides and currents actually run parallel to the beach and if they are strong a grip lead will be needed as a plain lead will be pulled along the beach and into very shallow water as the diagram below shows.

Grip Lead vs. Plain Lead
Angler 1 is using a grip lead meaning their weight stays near to where it was cast. Angler 2 is using a plain lead that moves sideways and closer to the shore, cutting down on the distance originally cast. Angler 3 shows what happens if a plain lead is used in a strong tide. The lead has been forced back by the strength of the tide and will only be in a few inches of water far along the beach, meaning they have little chance of catching anything.

In harbours and estuaries which have been artificially narrowed by the building of piers and breakwaters the tidal flow can be incredibly strong as a large amount of water is forced through a relatively small gap. The Bristol Channel is one area where this happens and a fierce tidal flow results. In some marks it is impossible to hold the seabed with any kind of weight and fishing is essentially impossible on a big tide. Many marks around the Bristol Channel offer good fishing on a neap tide but prove unfishable on a big spring tide. When fishing from any area with strong tides and a big tidal range it is important that anglers carry out some research beforehand in order to avoid placing themselves in dangerous situations.

How Does the Tide Affect Fish Behaviour?

There is still a lot of mystery as to the way tide affects the ways in which fish feed and behave. The simple fact is that no one can say for sure how the tide affects the behaviour of fish. There is a lack of peer-reviewed scientific research into this topic, and the trends anglers have discovered appear to have been worked out through observation and trial and error. For example, anglers may have noticed that during a strong spring tide worms and shellfish are dislodged from their homes and the fishing improves as various species of fish hunt for this easy source of food. Similarly, strong tidal flow can create gullies along rocks and other features, channelling food into these areas and making these times the ideal time to fish these marks. Some species also react differently to the tide. Bass, for example, can feed well during a strong tidal flow when they will hunt preyfish, whereas mullet prefer slack water when they will come into harbours and estuaries to feed. Shoal fish, such as mackerel, may come within range of anglers fishing from pier and rock marks when the weather is calm and the tide is weak, but stay further out at sea during strong spring tides, especially when they are combined with bad weather. Again, local knowledge will help understand how different marks fish during different stages of the tide.

Beach Fishing and Tides

Different beaches fish differently over different stages of the tide. Many steep shingle beaches will fish well regardless of the stage of the tide as there is always a good depth of water to cast into. However, on some shallower sloping beaches, the best fishing can be had at low tide.

Beach High Tide

Beach Low Tide

This is because the beach may slope much more steeply from the low tide point onwards, as the diagrams above show. Yet again a mix of local knowledge and trial and error will allow anglers to work out the best stage of the tide to fish any beach mark.

Piers, Jetties and Breakwaters

Saltburn Pier, Cleveland
Many stilted, promenade style piers, such as this one at Saltburn in Cleveland, are unfishable at low tide as they completely dry out.

Stilted promenade style piers often dry out fully at low tide, meaning that fishing can only take place over high water. Again, spring tides will see the longest fishing sessions available as the tide will come in higher and take longer to go back out. These types of piers can fish well in calm conditions and weak tides as species will swim around the supports of the pier looking for food. Solid stone piers which form the entrance to major ports and docks do not generally dry out and are often fishable at all stages of the tide. Local knowledge is again key, as certain parts of the pier may fish differently depending on the exact tide. In big tides and bad weather piers and jetties can be dangerous, as waves can sweep over fishing positions, putting anglers at risk.

Tides and Rock Marks

Rock Mark
Rock marks can be hazardous in certain tidal conditions.

Again, there is such a variety of rock marks around the country that it is impossible to come up with solid advice about which state of the tide is best to fish these marks. Some rock marks offer better fishing over low water, while others such as rock ledges and cliffs may fish better at high tide as the water level rises and provides a greater depth of water to cast into. Yet again, it is local knowledge that will inform anglers of the best tides to fish rock marks. Safety is always paramount in this type of fishing – if there is any risk at all that waves could sweep over a rock mark then it should be avoided. Anglers should always be careful of stepping on slippery rocks as the tide goes out, and watch for getting cut off by an incoming tide.