UK environmental research specialist APEM Ltd has expanded the scope of its aerial surveys by bringing a Vulcanair Observer into service. "The Observer is specifically designed as an aerial survey platform," says md Dr Keith Hendry. "It has an integral survey hatch and a Perspex nose making it ideal for aerial survey work and remote sensing."

He adds: "We have just sold our previous aircraft, a Cessna 172 which was also photo-modified. Twin engines give us much more flexibility in terms of range, speed to survey site and of course being able to undertake surveys over large expanses of water."

The company, brainchild of fish biologist Dr Hendry, was launched in 1987. It is a niche environmental consultancy specialising in undertaking applied research, surveying and managing aquatic habitats such as rivers and lakes together with coastal and offshore areas.

It has grown steadily over the years and now employs 50 scientists covering all aquatic disciplines including fisheries, ecology, water chemistry and hydrology in freshwater and marine environments.

APEM has three main laboratories in England at Manchester, Oxford and Dorset as well as offices in Bangor in Wales, and Dublin in Ireland and is currently expanding into Scotland. Dr Hendry says: "APEM undertakes environmental investi-gations, such as impact assessments, for the water and power industries. For example we investigate the effects of abstraction by water companies on rivers and lakes, investigating the impacts on fish and river ecology. We are extensively involved with both the conventional and renewable power industry. This includes examining the effects of cooling water discharge for power stations on rivers and coasts, thermal plume analysis and assessing the impacts on water quality and ecology.

"We are also involved in the two UK barrage projects, the Severn and Mersey, and the Solway Tidal Scheme, investigating the effects of these renewable energy proposals on fish populations. Offshore windfarms are another area of expertise, where we are developing innovative high resolution aerial survey techniques to assess bird populations before and after construction."

He adds: "Other areas we are involved in include river geomorphology assessment. Our aerial survey equipment can get down to a ground resolution of around 2 cm. With this we can undertake detailed assessment of riverine sediments, gravels, cobbles, boulders and using colour, sands and silts. This enables us to investigate the effects of hydropower schemes which have the effect of interrupting gravel (sediment) transport downstream, leaving large areas of river bed denuded of gravel. This has knock-on effects for spawning fish."

APEM also uses infra-red photography to identify invasive plants, accurately mapping them along river corridors so that eradication can be effectively targeted.

Hendry reports that aerial survey has been a substantial growth area for the company over the past four years. "We expect this to accelerate," he adds. "For offshore windfarm bird surveys, our new methodologies have resulted in immediate success, having been well received by both the power companies and regulators. Similarly our work in rivers is set to increase dramatically with the launching of our Fluvial Information System software (FIS). This combines particle sizing with depth measurement to produce fish habitat maps for rivers as well as a host of other geomorphological information required for the new EU Water Framework Directive. Our aim is to make the FIS an essential monitoring and information tool for rivers, not just in the UK but across Europe."

The purchase of the six-seater Vulcanair Observer was funded by Lombard, the asset finance arm of The Royal Bank of Scotland. Based at Leeds/Bradford airport the Italian-built aircraft has a maximum speed of 370 kmph and a maximum range of almost 1,600 km.

Hendry says: "The aircraft has been fitted with the latest in geographic information system software and we believe this will be a real benefit to both new and existing clients."