I think many of you will be delighted to know that big spider season is ending soon. These big spiders which come into houses in autumn, are looking for mates. These unseen females are much stockier than their suitors, and generally stay in their webs, often hidden from pulic view. In order to let their boyfriends find them they release pheromones onto the air, and the males come running.
The males then live for a number of weeks or months in the webs with the females and leave before the young are born, or are killed and eaten for overstaying their welcomes. As a result, sensible males who leave early can grow to immense size and apparently live quite a few years. But by now most of the females have mats and will stop releasing pheromones and the males will go back to their regular lives, if they avoid the various predators that delight in eating them, especially Robins and Blackbirds, but Wrens too.
As April draws to a close we have reached high Spring, and this year has been a superb one. The steady weather conditions and good levels of sunlight have transformed the landscape. The shrubs and trees are beginning to bloom, adding to those of the undergrowth. This year the lilac trees have been early and especially impressive due to the dryness – in wet years the fleshy, fragrant flower-spikes rot rapidly. This year they are the magnificent ornaments they are meant to be.
But the undergrowth is only really getting started. In woodlands, and on the narrow lanes of Wicklow you will find intoxicating seas of Ramsons (Allium ursinum), the wild garlic. Driving along these lanes with the car window rolled down can be something of an aromatic adventure in springtime.
The flowering plants depend on sunlight, and in turn the invertebrates, particularly insects, depend on the flowering plants to provide serious energy, in the form of nectar and pollen. Of course, the plants are equally dependent on the insects to fertilise them so there will be more plants, and insects, next year. Away from the trees the Daisy (Bellis perennis) are one of the most important nectar-producing species, supporting every conceiveable pollinating creature, and reaping the rewards. Wild meadows are very important habitats for this reason.
As the length of days and exposure to sunlight increases the number of plant species in bloom greatly increases, which in turn supports more and more pollen and nectar-dependent organisms.
This, in turn, leads to an increase in predator numbers. One of the most interesting and unusual predators of other insects is the Yellow Dung-Fly. These flies are normally seen perched on cow dung in huge numbers, where they mate, lay eggs, and attack and eat other insects attracted to the dung. However, in spring they feed mostly on pollen, because there is so much of it about, and their prey numbers are still growing. The fly in the photo is covered in pollen, having clearly gorged, probably on daisies.
Because of predators nectar and pollen-feeders have to be able to defend themselves: in spring you will see many species of bee, all armed with potent stings.
However, many of the bees you will see in Wicklow are not bees at all. Instead of developing toxins, many species of fly have opted to imitate bees, and it is difficult even for naturalists to tell them apart. The trick is to look at the heads: the flies have large round heads with little or no fur, and they have only stubby antennae, whereas bees always have long antennae curling from their heads.
However, flowers do sometimes get more than they bargained for, slugs will also happily eat pollen, and the entire flowerhead. But only very, very slowly, and very occasionally.
Thanks to the abundance of nectar many insects can take time off to find mates and breed, something that would be impossible to do if they didn’t make a profit when it comes to feeding. The beautiful little Orange-tip butterflies are only with us for about four or five more weeks, so watch out for them in gardens, along roads and flower-filled meadows with good hedgerows. They are now taking the time to find mates and breed, and the sight of a pair of them dancing over hedges is a strong sign you will very soon witness a marvellous event: I saw Orange-tips mating for the first time in my life this week. They are so common at this time of year, it is strange how well they hide their social lives. Maybe they’re marvellous camouflage prevents the casual observer from noticing. However, I’m not a casual observer, so it is rare: if you do witness this event you are one of a lucky few.
The sunlight, and longer days are warming the valleys of Wicklow. The smaller wildlife, on which all others depend, are starting to steal the show. While strolling in a garden or along a village lane you might see a scarlet-coloured fluttering object drop from the sky and out of sight. It might appear a little later, but if not, look on the low-growing foliage for the beautiful and aptly-named Ruby Tiger moth (Phragmatobia fuliginosa), which emerges from its pupal coccoons in April and May, to take to the sky. This species employs bright colouring to warn of distasteful toxins in its body.
At the other end of the colour spectrum is the Holly Blue butterfly (Celastrina argiolus), a stunning little spring butterfly that loves to bask on wide hedgerow leaves. This butterfly likes woodland glades and narrow laneways, aswell as gardens.
If you are very lucky you might even be fortunate enough to see a mating pair. Mating is a quiet and symmetrical affair. The lovers rest, joined by their abdomens, but facing in completely opposite directions. They only move to angle their wings in the sun.
However, the sunlit leaves are not necessarily safe places. Predatory invertebrates brazenly wait, motionless in the undergrowth, for unwitting visitors to arrive to provide them with lunch. Crab spiders wait on the leaves, and will soon be hiding among the blossoms.
However, many small creatures are fortunate enough not to hide on leaves. Your best chance of seeing the Early Thorn moth (Selenia dentaria) is now in April, usually perched on timber door or window frames, and garden sheds. The first generation male, pictured, is perfectly coloured to match dark timber, and dry leaves in the hedgerows.