Nature 2007 April

All simply in the springing of the year*

January and February provided warmer days, colder nights and a bucket-load of rain. The rate at which the well is rising (55 inches per week) suggests the water table has a head of steam behind it and this is an indicator as in 2000/1 that there could be flash floods before the year is out. The Met Office is cautiously suggesting that Spring and Summer will continue to be a little wetter and somewhat warmer than average (but not necessarily at the kind of record levels we have had in recent years though).

Beech leaves burst forth in April. But dates can vary by 3-4weeks from year to year. Last year it was late (28th) held back by a cold snap in March but in previous years it was during the first 10 days of the month. Imagine the Chilterns without Beech trees! Research reported last September suggests that the number of trees suffering from water stress had increased four-fold over the last 15 years. Young trees (under 50 years old) are showing these signs in particular. The degree of damage being that one should only expect once the tree has reached at least 140 years. Slowly the Beech will be replaced by Oak and Ash, which are both better able to withstand summer drought conditions. Lime, which was largely replaced by Beech when plantations of the latter were planted to serve the furniture trade, could make a comeback. But Bluebells which rely on late arrival of the tree canopy could also suffer.

I was sitting by the PC seeking inspiration for this article and just in case I needed a reminder that this is the time of year when wildlife emerges from all quarters I heard scratching coming from the air-brick of the long-disused chimney beside me. Closer inspection revealed the antennae of a large insect exploring the gaps clearing with a view to squeezing through the vent. Freedom came just a few seconds later when out popped a rather sooty, but huge queen hornet. Despite knowing the last thing on a hornet’s mind is to attack they are nevertheless intimidating close up. Just as well I had managed to scramble for a glass and sheet of paper as it was clearly finding its bearings and was became extremely animated. I’m sure the fact that Spurs had just beaten Watford (aka the Hornets) 3-1 was just a coincidence. Safely confined behind a piece of A4 I gave it a quick once over for a few moments. A magnificent insect close up and deserving much better press than it gets. However, its persistence in pushing its legs and antennae around the edge of the paper was decisive in my decision to set it free quickly. Luckily it fancied exploring the great outdoors more than our house and headed of (made a bee- line would be quite descriptive here but seems contradictory) towards the woods. No doubt I will encounter her offspring in the not to distant future.

Hornets aren’t the only wildlife that undeservedly and perennially receives bad press. Stoats, for example, have never recovered from being maligned as the villains of the piece (along with the weasels) in Kenneth Grahame’s Wind in the Willows. They have a reputation of killing rabbits and mice mercilessly, giving out a piecing scream before the ‘coup de grâce’. Normally crepuscular (appearing at twilight) but May is the best time to see these illusive animals as the females need to hunt in daylight to ensure sufficient milk for their young (kits). It exchanges its all-white ermine coat, from which it gets its other name, for a rich brown coloured covering to its long thin body, retaining just a white front and with a black bottlebrush tail. The white fur was used in the ceremonial dress of the Lord Chief Justice and an ermine as a pet appears in paintings of monarchs such as Queen Elizabeth I – a symbol of purity.

If you read this at the start of April Swifts will be leaving their over-wintering sites in tropical Africa (not emerging from English river mud-beds as Gilbert White concluded in his Natural History of Selbourne). If you read this article in May those Swifts will already be arriving. The long journey has depleted their fat supplies and their arrival therefore hopefully coincides with an explosion not just of flying insects but many non-flying invertebrates and in particular spiders, which make up what is known as aeroplankton. There is no time to lose as not only must they feed continuously on the wing, catching each morsel individually, but also adults must find a mate and breed whilst in flight. Most incredibly though, on warm evenings as light fades, Swifts will spiral higher and higher so they can catch up on their sleep by having short naps. Swifts are gregarious birds and will call to each other to encourage communal flying They will also vary the altitude at which they fly to ensure they maximise the availability of food supplies. As high altitude flying relates to high pressure and vice versa they have long been used to predict the immanent arrival of rain.

For the past four years of writing these Nature Notes I have received reports each year in April of the first ‘soundings’ of Cuckoos in the area. Dates have varied from between 19th to 27th of the month. This is about 10 days later than the Scilly Isles where they are first heard in the British Isles. I suspect we will have our first record early rather than late again this year. Cuckoo Pint, aka Lords and Ladies or Arum Lily is out at the same time (as are the cuckoo flower and cuckoo bee). Look out for both the purple and yellow club-shaped inflorescences as well as the spotted and unspotted varieties, which appear in different frequencies from place to place

Finally, Springwatch returns to the BBC and should be on our screens by the time HTN hits the streets.

(*Quote by the way is from Robert Frost).