for the females: they are remarkably sedentary as adults so use this period to colonise new areas.
The larva then picks a secluded area and begins to pupate, a remarkable process in which the larva’s body, including all the organs, is completely broken down and then reconstituted as the adult form takes shape. This process takes just over a week for the females and slightly longer for the males as they have to undergo a more drastic alteration due to their need for the power of flight.
The first glowing females of the season are usually seen from mid-June, and, with their segmented bodies and absence of wings and wing cases, retain more than a passing resemblance to the larvae. The light organ is positioned on the underside of the abdomen and consists of two luminous bands and a couple of luminous spots set either side of the ovipositor, the organ from which the eggs will be deposited. The glow-worm’s light is produced by a string of chemical reactions between a small protein called luciferin and a large enzyme called luciferase. Though the complex reaction is still not totally understood, it is an incredibly efficient process: 98 per cent of the energy is released as light, compared to a measly 5 per cent in a light bulb, in which the vast majority of the energy is wasted as heat. This means that the light organs of the glowing females are completely cold to the touch.
Rough grassland with little light pollution is essential if you are a female glow-worm desperate for attention
David Woodfall
Andy Rouse
It is only virgin females that glow; once a female has mated and begins egg laying, the light organ has served its purpose and is switched off.
The glowing performance usually commences soon after dusk at around 10–10.30 p.m. It is thought the turning on of the light is triggered by a drop in light intensity below a certain threshold level, which explains why glow-worms that advertise in the darkness of a woodland edge will begin glowing earlier than populations in predominantly grassland locations. The female will generally display close to the ground, or up to a maximum height of around 40 to 50 centimetres if she feels a higher vantage point would be more beneficial. Females will even glow during rain, but usually stay closer to the ground during inclement weather.
Because the light organs are set on her underside, the female also has to twist her abdomen around to make sure that any males flying past will see her lights. This twisting is often accompanied by a swinging of her abdomen from side to side like a metronome, which, to complete the exhibition, gives the effect from a distance of the light brightening and dimming.
The display usually lasts for a couple of hours, after which, if she hasn’t been successful in attracting a mate, she turns off the light and retreats back into the grassy tussocks to prepare for a repeat performance the following night. The females are remarkably sedentary and are often seen displaying from the exactly the same spot until they either snag a mate or die an exhausted spinster after around ten consecutive nights of lighting up the night.
The numbers of glowing females can vary enormously from just a few females at small sites, to Brush Hill in Buckinghamshire, the location thought to contain the largest colony of glow-worms in Britain, with 320 females counted in one visit in 2007.
The male glow-worm looks very different to the female, because he has to be mobile in order to track down the displaying females, and so has a fully functioning pair of wings tucked away under his wing cases. He normally takes flight shortly after the females have started glowing and flies a couple of metres above the ground until he spots a virgin female. He will then drop out of the sky with unerring accuracy next to the female and attempt to climb on her back. It is not uncommon to have a number of suitors chasing a single female, meaning a form of rugby scrum can sometimes ensue as they jostle for position.
Like the adult female, the male cannot eat and so has a very limited adulthood. Once mating is over, the exhausted male dies, usually no longer than a week after emerging from his pupa for his date with destiny. His death is closely followed by the female’s after she has dutifully discharged her eggs to produce the next generation.
Although found all over Britain, glow-worm colonies are most abundant in southern England. They can be seen in grassland of every type, apart from sites that have been ‘improved’ with fertiliser or heavily sprayed with insecticides, and also occur in moorland, heathland and occasionally woodland. The spectacle is mostly a rural phenomenon, and country anecdotes abound of glow-worms being put in jam jars to read by at night!
The last 50 years are thought to have seen a steady fall in the number of colonies thanks to the usual lethal cocktail of habitat destruction, fragmentation and pollution. Artificial lights may well also present a problem as the males could be distracted by the lights and find it difficult to spot the females in the glare. Let’s hope, however, that these magnificent insects continue to bring light into our lives for many years to come.
You would think there could scarcely be enough room for a medium-sized native carnivore to live alongside us in Britain. Yet the cunning and resilient fox has led to it not just surviving, but actually thriving, anywhere from on rural farms to in the heart of Britain’s biggest cities. It’s a tough life, though, and particularly among the urban residents it’s a ‘live fast die young’ scenario, where cubs must learn the tricks of their trade quickly to give themselves a chance of breeding the following year.
Fox cubs
WHEN
Late April until the end of June
WHERE
Widespread and can be seen anywhere, although easiest seen in cities such as London and Bristol
A fox cub seemingly without a care in the world, but it can be a surprisingly short and brutal life.
Andy Rouse
The word ‘fox’ is considered a very old English word that came from the proto-Indo-European word ‘puk’, or Sanskrit ‘pucca’, which both mean tail. Our only native canid (member of the dog family) was widespread in Britain from the end of the Ice Age: evidence of fox remains reveals that the earliest human inhabitants hunted them for fur and meat. Despite a history of persecution through the Middle Ages, the number of foxes was scarcely reduced until the rise of pheasant shooting in the Victorian era, when an army of gamekeepers was employed to wipe out the ‘ vermin’. The liberal use of vastly improved guns, traps and poisons meant that, at the turn of the 20th century, foxes had been virtually exterminated from much of East Anglia and the large estates in eastern Scotland. But, as gamekeeping declined after the First World War, fox numbers recovered, and current estimates indicate the population has remained largely stable over the last 30 years at a pre-breeding population of 250,000 adult foxes.
Despite foxes being recorded from the length and breadth of mainland Britain, their distribution is far from even, with the highest densities occurring in southwest England, the Welsh Borders and up into southern Scotland. While foxes can be found anywhere from moors or woodlands to the centre of towns, they prefer fragmented habitats that are able to provide them with a wide range of cover and plenty of boundary edges along which
