Читать книгу A Natural Year - Michael Fewer - Страница 13
ОглавлениеMarch
Oh, what a dawn of day!
How the March sun feels like May!
– Robert Browning, ‘A Lovers’ Quarrel’
primroses
MARCH COMES IN WITH THE WELCOME appearance in the garden of the little brown-tailed bumblebee, buzzing around seeking out early nectar plants. We have twenty species of bumblebee in Ireland, but I find it difficult to identify more than a half dozen. They are by far our most efficient wild pollinator, and our most numerous and perhaps our most loved insect. I say most loved, because their slow, lazy humming buzz is the sound of summer, and their colourful, furry bodies are a pleasure to behold as they lumber from flower to flower, sometimes with a heavy dusting of nectar. Bumblebees are under threat, however: their habitats, in the countryside and in suburban gardens, are being seriously eroded by the expansion of nitrogen-rich grasslands and ribbon development, by the increased popularity of hard surfaces and decks in gardens, and by the proliferation of flower- less lawns. The dandelion is an early, rich source of nectar for the bumblebee, but it is also one of the most hated ‘weeds’ in a garden, and rarely tolerated. We cannot do without bees, and particularly bumblebees: the only hard economic figures I have to indicate the importance of these insects are from 2008, when bee pollination generated €14.4 million of the horticultural produce in Ireland, in addition to honey sales of €992,000.
I don’t believe that the population in general has realised that a global crisis is looming due to the continuing rate of extinction of our insect population. We simply cannot do without them because of their essential part in the production of the food we eat. Although the bee is perhaps one of our best-known insects, most go unnoticed by people generally. Here in Ireland, we have ninety- eight species of bee, and one-third of these are facing extinction. Our bumblebee population has declined by 15 per cent in the last five years alone, and we rely heavily on the bumblebee for pollination. This means that, if nothing changes, and we apply the same figure for every five years into the future, within forty years the bumblebee population will be less than a third of what it is today. In a global warming context, however, this situation is likely to be accelerated. These problems are being caused by the way we live today, and we need to wake up and deal with them.
Glendoher, 7 March
The birds are in full mating mode now, and I find that, if I have patience, watching their activities in the garden reveals a lot about their particular displays. The experts say that while all cock robins sing, only about half of hen robins do so, and their song is indistinguishable from that of the cock. Why only half of them sing is a mystery to me, but this is the case; those hens that do sing usually cease when they pair with a cock.
At breakfast one March morning, I noticed a strange-looking bird in a birch in the garden. It resembled a robin with a large black spot in the centre of his breast, and held his head at a peculiar angle. When I got out the binoculars it became clearer. It was indeed a robin, which I presumed to be a male, and it was going through a courting display for another robin on a nearby branch. He had his head arched back so that the beak was pointing towards the sky, which made him look almost headless from where I stood. The stretch on the skin of his breast was such, however, that there was a large gap in his red plumage, which appeared like a black patch. As he perched in this stance, he swayed back and forth slowly, seeming to hypnotise the female, who watched him intently and curiously, head to one side. This went on for about five minutes, the male moving closer to the female twice, before they both flew off, buzzing around each other.
The cock robin draws the attention of local hens to his presence by his song, and it is after this, and sometimes weeks later, with the hen’s interest aroused and with the nest completed, that the courting display take place. It is followed by coition, which is infrequent and without any display. Other than bringing the hen food offerings, the cock tends to ignore her from thereon in.
When the garden is alive with buzzing bees, flights of mallards are constantly zooming past the house and around the field, and we see our local herons flying together in close formation, spring has definitely arrived.
We have a pond-skater on our pond. He may have come in larva form with a jam jar of pond muck I brought down from Hellfire Hill to give a bit of life to the pond, or, even better, he’s a descendent of the half dozen skaters I introduced last summer. Of the great diving beetles and the tadpoles I also brought, there is nothing to be seen, but what can I expect? Tadpoles are a favourite food of the diving beetle, which keeps out of sight most of the time. This mini- monster, growing to 3.5cm long, is a fierce predator, and having cleared one pond of prey, it flies on to the next seeking more victims. It has sharp jaws that bite into its prey, injecting enzymes to turn the unfortunate’s insides to easily digested liquid. Even the fish are hiding at the moment, so there is little activity in the pond, other than the lone skater.
Our nearby mountain stream, the Owendoher, has not yet been fully enclosed by the foliage of the ivy-clad trees that overhang it, and I enjoy spending time on one of the little footbridges across it, waiting and watching: if I am taking the bus to town, I often leave early to allow myself ten or fifteen minutes at the river. Last week I was rewarded by the sight of, not one, but two dippers foraging along, above and in the waters, and a grey wagtail, one of our most elegant and colourful birds, bobbing its tail at the water’s edge.
One of the joys of getting to know the magic of nature is to look into what seems ordinary and discover the extraordinary. The white-breasted dipper, a common enough bird on our streams, is a fascinating example of the exotic in the everyday. It’s not particularly extraordinary looking: it is a bit like a chubby blackbird with a brilliant white bib, and is usually seen perched on a rock in a fast-flowing mountain stream. If it’s bobbing up and down, it’s definitely a dipper, and it’s from this habit that it gets its name. While its bib and its habit of bobbing up and down are not particularly remarkable, the dipper’s method of feeding certainly is. This bird leaps into the water off its stony perch, and actually walks along the bottom of the stream, swimming a little as it hunts for a lunch of mayfly nymphs. It also finds the larvae of the caddisfly on the bottom, and crunching the gritty larval case in its beak, it releases the juicy larva into its crop.
The caddisfly larva is another extraordinary wonder of our natural world that few know about. Caddisflies are inconspicuous browny/grey insects that are related to moths. They also are mainly nocturnal and feed on nectar. They have a short life, about a month, at the end of which they lay their eggs on vegetation near water bodies or streams. When the eggs hatch into larvae they enter the water and immediately begin the extraordinary task of building a tubular shell or armoured case around their soft bodies, a little like how a hermit crab has to find an unoccupied shell in which to live. They produce silken thread and use it to create the case by assembling tiny pebbles, twigs, leaves and sand into a tubular shape, open at both ends to allow it to feed. Once the larva becomes a caddisfly, it cuts itself out of its case and swims to the surface of the water, and immediately takes to the air.