Black ants are commonly found throughout the UK, and although they nest outdoors, they are often found inside. Ants range in size from 1mm to 52 mm and colours can vary; most are red or black.
Black/Garden ants (lasius niger)
Perhaps the best known ant in England is Lasius niger, the common black garden ant. It is well known due to its tendency to enter houses. It nests under pavements, in soil, along the edges of lawns, in fact almost anywhere. It is a very quick, robust and prolific ant, using formic acid and its jaws as a means of attack/defence. Colonies can be as large as 15,000 workers, though about 4000 to 7000 is more average. Typical prey include insects, nectar, and even the bodies of their own dead, or ants from other colonies. They are also very fond of sugary substances
Another common ant found in gardens is Lasius flavus, the yellow meadow ant. These ants build small mounds in our lawns and are often mistaken for red ants due to their yellow-orange colour, yet they are no more harmful than their common black cousins, Lasius niger. They are the most skilled nest builder found in the UK and can also be found in fields and meadows where they build much larger mounds. Lasius flavus tend to forage below ground and therefore are not often seen except perhaps when its nest is disturbed, or during the annual mating flights. They feed on small insects and mites that stray into their tunnels.
Red Ant (myrmica rubra)
There are seven species of the Myrmica family found in this country. These ants tend to be a deep red in colour and can deliver
a painful sting. The most common of the seven species is Myrmica ruginodis which can be found throughout Britain and lives in small colonies with between 100-300 members They are polygynous, meaning they can have many egg laying queens in one colony. They are aggressive and seem to be happier attacking than running away.
Red Wood Ant/Horse Ant (formica rufa)
Another common British ant are those belonging to the species Formica, also known as the wood ant. Many of these species build huge mounds from pine needles and other woodland litter on the edge of forest clearings or pathways, and can number more than 100,000 members per colony. These ants are large, aggressive and attack by biting and spraying formic acid very effectively if disturbed. The largest ant in the UK is Formica sanguinea. It raids colonies of other Formica species, such as Formica fusca and steals their brood, taking them back to their own nest where they raise the hatching workers as their own. Surprisingly these ants generally do not kill the workers of the nests they raid unless the defending workers try to stop the sanguinea invaders from taking what they want. Formica rufa are polygynous and can have hundreds of egg laying queens in one nest. They are found in Southern England as well as other European countries.
Another wood ant species. This one is black and more timid than its red cousin. They prefer to nest under rotting logs and are found from the Midlands down to Southern England. They have populations of usually less than 1000, and although can be polygynous, they do not normally have very many queens in each colony. They have extremely good eyesight but tend to be very timid, running rather than fighting.
This ant is a small black stinging ant. It is typically found along the coasts of Southern and Western England. They can have nests containing up to 30,000 ants, but the average is perhaps 10,000. An interesting feature of this ant is that it appears to bury its food in mounds of soil.
Ant Colonies and Flying Ants
Every summer around late June to early August great flights of winged Lasius Niger ants take to the air to mate. It is common for there to be 2 or even 3 separate mating flights during the summer, as some colonies seem not to release their winged members at the same time as many others.
During these mating flights the large winged queens, and smaller winged males will take to the air, following the thermal currents, and find themselves a mate. They may mate in the air with the male perched on top of the queen, or they may mate on the ground. Once mated thequeen will fly off to find a suitable nesting site, whilst the male will survive perhaps a day or two before curling up and dying. The queen may go on to mate with several more males before finding a nesting site.
Once the queen has landed she uses her middle and hinds legs to “unhook” her 2 pairs of wings, these will be discarded on the ground and forgotten about. She will never fly again, and the wings will only become a nuisance to her. Once she has found a suitable nesting site, the newly fertilised queen ant will urgently dig herself a tunnel leading to a small chamber. She will seal herself in the chamber and, unless she is forced to, she will never emerge into the sunlight again. From this point onward her lifeis lived in total darkness and she will become acutely photophobic if exposed to the light henceforth.
The new queen may lay eggs straight away, (some species do, whilst others do not,) or she may wait until the spring. However, if she lays her eggs straight away, and the weather stays warm or mild, then the eggs will hatch within 8-10 weeks. Usually, at least as far as Lasius niger are concerned, the queen will create this new nest completely on her own, though it has been known for Lasius niger queens to come together and cooperate in the raising of the first brood. However, Lasius niger are strictly monogyne, meaning that each colony will only tolerate one parent queen. If more than one Lasius niger queens raise brood together, they will soon fight to the death once the first workers have hatched, until only one queen remains victorious.
Whilst the Lasius niger queen is awaiting the emergence of her first workers, she will neither eat or drink, though she may eat a few of the eggs she has laid, but generally speaking she will live off the now defunct wing muscles in her thorax, which will breakdown and be converted into energy, and egg production.
When the first workers emerge they are very small and timid, compared to the later generations of ant that will follow. They immediately begin to expand the nest, tend to the queen and brood, and eventually remove the seal from the chamber entrance created by the queen, and forage above ground for food. This is a critical time for the new colony as food will need to be gathered quickly in order to feed the near starved queen, who would have lost about 50% of her body weight, and to provide her with the nourishment needed to create more eggs. From this point on the queen will cease all other functions, but will instead become an egg laying machine.
As future generations of ants are produced, they will be bigger, stronger, and more aggressive than their older sisters (worker ants are all female). After a year or so the colony will enter an exponential stage in growth when the population will rise dramatically. Once the colony is well established, which can take a couple of years or more, the queen will start to lay eggs that will turn into winged males, and later on, when the colony resources are plentiful, large winged queens will appear, and the whole cycle will start again.
There are several other methods that ants use to create a new colony. Some of the polygyne ((more than one parent queen) species will be created by several queens who come together to start a new nest. Unlike a group of cooperating Lasius niger queens, Myrmica rubra queens will continue with several queens after the first batch of workers are hatched, and will continue to function as a single colony with each queen contributing to the egg production of the colony.
“Budding” is another method in which new ant colonies are created. An example of this is shown in the southern red wood ant Formica Rufa. These ants can have over one hundred egg laying queens in each colony, and once a colony becomes large enough, one of more of these queens may leave the nest, taking hundreds, or thousands of workers and brood with her. They will found a new colony, usually not far from the parent nest.
Parasitism is another method by which newly mated queens of the species Formica sanguinea, the largest of the native British ants, may create a new colony. A newly mated queen will force her way into the nest of a smaller species, such as Formica fusca and snatch some of the brood. She will then create a sub-cell within the nest and defend it against the colony’s workers or queens. The queen may kill the parent queens herself, or she may wait until the brood she has snatched emerge, and they will associate themselves with the sanguinea queen, and kill the original queen themselves.
Why do ants come indoors?
The ants found indoors are usually worker ants, which are foraging for food for the queen and the grubs. They have found that buildings inhabited by humans are a good source of provision, particularly sweet or sugary items. Worker ants are scavengers and collect seeds, nectar, and even dead insects to take back to the nest. They also prey on greenfly, blackfly and other small insects, even caterpillars, so they do have some redeeming features.
How do I prevent an infestation?