With their size, colouring, leisurely flight and almost stone-solid appearance as well as regular raiding visits to garden ponds Grey Herons (Ardea cinerea, wingspan 185cm) are among our most familiar wetland birds. They eat fish but plenty more besides, including amphibians, reptiles and ducklings, with up to 500gms a day needed. Their nesting requirements can place them at something of a disadvantage, since they normally use trees with the nest roughly 25 metres above the ground. The eggs are laid fairly early in the spring, and strong winds can pose a major problem.

The RSPB reserve at Northward Hill in Kent, which was under threat had a new airport been built on the coast at Cliffe, has the highest concentration of Grey Herons in Britain. This site, together with the Poole basin in Dorset, also hosts significant numbers of a member of the family which is steadily expanding its range, the Little Egret (Egretta garzetta).

Incidentally, quite why successive governments believe an increase in air traffic, with more airports and runways constructed, is either desirable or necessary is beyond the understanding of anyone with even two brain cells to rub together. The plans to build a new runway at Stansted Airport announced early in 2007, providing facilities for an extra 200,000 passengers a week while destroying homes and habitats, are a sad but typical example of the bizarre thinking behind this approach.

The same can be said for the intention to lengthen the runway at Lydd Airport in Kent by more than 400 metres and build a new terminal to allow two million passengers a year. Lydd is adjacent to the magnificent Dungeness National Nature Reserve and RSPB reserve, so it would be difficult to come up with a stupider and more irresponsible place to suggest airport expansion.

To place this in wider context, the advantages of such developments are nil; the disadvantages are gigantic. The fact that more people than ever wish to fly abroad on holiday has no bearing whatever on what is necessary for society or the economy.

This might be disputed by the British Airports Authority, which appears to believe that if there is economic growth, citizens must have the right to fly wherever they want, whenever they want. As non sequiturs go, that is a truly presidential effort, but what do you expect when the idea is coming not from an objective observer but from an organisation which primarily is interested in making money, and does so handsomely to the tune (before tax) of £505 million in 2002 and £796 million in 2006. The more people fly, the better it is for BAA: there were 221 million passengers in 2002 and 262 million in 2006.

Given the amount of fossil fuel expended and pollution emitted by the average jet passenger plane – a Boeing 747 burns 15,500 litres of fuel an hour, as well as throwing out bulk nitrogen on take-off – any runway construction or increase in flights, be it at Stansted or anywhere else, will be a scandalous example of unsustainable development. In the same way that importing fruit and veg from the southern hemisphere during the winter is an absurd waste of ‘air miles’.

Defenders of increasing the level of transportation by air claim, accurately enough, that planes account for around three per cent of global carbon emissions. What is not pointed out is first, that this is the fastest growing source of emissions, and second that, according to the Intergovernmental Panel on Climate Change (IPCC), this form of transport will account for 15 per cent of all carbon emissions by 2050.

If anything, the public should be discouraged from flying, not encouraged, and to this end, reassessing and/or selectively disregarding the Chicago Convention of 1944, leading to the novelty of taxing aviation fuel, with the proceeds ring-fenced for use in protecting the environment, would be a step in the right direction as regards environmental responsibility.

The Convention baldly states: "fuel, lubricating oils, spare parts, regular equipment and aircraft stores on board an aircraft of a contracting state (...) shall be exempt from customs duty, inspection fees or similar national duties or charges".

There are also Air Service Agreements (ASAs) between states governing the treatment of fuel loaded on to an aircraft. These usually contain a clause to the effect that fuel in transit or supplied in the territory of a contracting party is exempt from taxation.

There is, of course, no reason why such Agreements should not be renegotiated, and for what it’s worth the EU has been discussing the institution of an aviation fuel tax off and on since 1997. Indeed, the European Parliament has voted by 430 to 74 in favour of such an impost. Whatever validity the Chicago Convention had when promulgated, circumstances have changed dramatically since, and apart from anything else, where is the justice in taxing to the hilt petrol and diesel for road vehicles, while not taxing aviation fuel?

If people prefer to fly to or from Schiphol or Charles de Gaulle Airports, good luck to them. The supposed economic loss to Britain is not proven, certainly not as regards tourism, and anyway, we surely should be looking at the future, beyond instant gratification and supposed short-term economic success which may well ultimately encourage long-term decline.

Whatever the score there, Grey Herons seem to have increased significantly in numbers in the last 30 years, with anything up to 10,000 nests annually.

By comparison, the Bittern (Botaurus stellaris, wingspan 130cm), a stockier member of the heron family requiring extensive reedbeds in which to live and breed, is rare indeed but offers a tremendously heartening story in conservation.

Drainage together with agricultural ‘improvement’, plus hunting and possibly colder climatic conditions in the 19th century – Bitterns are distinctly vulnerable to severe winter weather – resulted in the species becoming extinct for breeding in Britain in 1868. The same thing happened in Sweden. A modest recolonisation occurred in Norfolk from 1911, leading to the individual and remarkable courtship ‘boom’ being heard from a peak of over 50 males in the 1950s. A radical decline then set in and by 1997 only 11 Bitterns were heard booming.

Action was needed, and showing its usual ability to combine science with passion the Royal Society for the Protection of Birds led the way in a united front of conservation groups that had government and EU support funded by the EU-Life programme. Reedbed habitats were made more suitable for Bitterns and in 2004, six years ahead of schedule, the UK population reached the milestone of 50 booming males set in the UK Biodiversity Action Plan. (The boom can be heard 5km away, and is the only real guide for calculating numbers.)

The next target is 100 booming males by 2020. Rising sea levels will not help the Bittern given that so many extensive reedbeds are close to the coast, including at the strongholds of Minsmere in Suffolk and Leighton Moss in Lancashire, but new beds further away, as at Lakenheath Fen, should help.

When breeding, Bitterns are exceptionally hard to see, but a number winter here, coming from Germany, Sweden and the Netherlands. The latter country, with at least 250 pairs, and France, with 300+ pairs, host the largest breeding colonies in western Europe. Ukraine has by far the greatest number in Europe at large with an estimated 20,000 pairs.

Close to London, Lea Valley in Hertfordshire and the Wetland Centre at Barnes have visitors each year and the pictured bird at the latter site offered exceptional views in 2006-7, with less of the habitual skulking behaviour associated with the species.

Images © Jeremy Early. All rights reserved.