Preliminary Ecological Appraisal

EcoNorth’s tree climbing A-team were out in force during September, undertaking a series of aerial inspections within a large cluster of mature and veteran trees, on the look out for roosting bats. With our endoscopes and climbing gear in tow, we headed south.

An aerial inspection, as the name suggests, involves accessing a tree canopy using specialist climbing equipment, which allows us – all licensed surveyors – to complete a comprehensive internal inspection of possible bat roost features from close range. Features of interest usually include woodpecker holes, lifted bark, branch cavities and hollow branch scars. Although this requires a head for heights, getting up close and personal offers a more robust assessment of potential roosts than is otherwise possible. Nonetheless, keep a look out next time you’re in the woods – chances are you’re not far away from a bat roost!

During the trip in Surrey we basked in the last of the summer sun, interrupted only by a few forgivable showers. The dry weather made for some brilliant climbing. Over the course of six intensive days,  our three person team managed to inspect over sixty trees scattered across six different sites. A handful of veteran sweet chestnut and English oak trees were especially tricky. One such sweet chestnut was the cause of three snagged and snapped throwlines – used to establish a climbing rope to a suitable climbing anchor – as well as the high density of perilously positioned bat roost features.

Most of the features inspected were considered superficial, that is to say they had no bat roost potential. However, the occasional woodpecker hole or trunk hollow cavity contained bat droppings, which were sampled and sent off for DNA analysis for species verification. Upon the completion of our climbing marathon, all of our hard won data was consolidated and issued to the client, which will ultimately inform the application for a Natural England Protected Species Mitigation Licence.

We had an adrenaline and fun filled few days, which was a great way to end what has been a very busy bat survey season.

Why would I need a tree climbing survey and what are the advantages?

Inspections or surveys from the ground may be hindered by leaf cover or ivy growth (often coinciding with the height of bat activity season), which can make it difficult to identify exactly where bats could emerge from or return to. Additionally, features that appear suitable from ground level (identified using binoculars) may turn out to be unsuitable upon closer inspection.

By climbing and inspecting trees, we can reduce or remove the limitations of traditional methods. This can be done through reducing the scope of, or even eliminating the requirement for, ground-based nocturnal activity surveys, which in many cases can save clients both time and money. Undertaking these surveys year round can reduce avoidable delays to projects.

How can EcoNorth help me?

At EcoNorth, we have bat licensed ecologists who hold CS38 Tree Climbing and Aerial Rescue Level 2 certifications.  We can undertake tree climbing surveys throughout Great Britain, tailored to your specific requirements.

If you would like to hear more about bats and our tree climbing service, please contact Thomas at: Thomas.Wilson@econorth.co.uk.