Yesterday I went on another of my work experience sessions with the National Trust at Quarry Bank Mill. Although it rained a little bit, we were actually quite lucky with the weather as Storm Doris had been through the area just two days before!
Whilst our previous two sessions had been focused on the River Bollin, this time we moved onto a different aspect of conservation and learnt how to conduct Phase One habitat surveys.
A Phase One habitat survey is usually the first survey carried out on an area and is a method of noting down the different types of habitat and any other important features present. It can be followed by a Phase Two survey (this is any survey that focuses on a more specific factor, for example a particular animal population).
When out in the field, notes need to be made quickly but also need to be clear so that they can still be easily understood at a later date. For this reason there is a key which is used in Phase One habitat surveys. For most features this just consists of a series of letters and numbers: letters are used for more broad categories while numbers are then added afterwards to indicate more specific details.
We were given the task of surveying three different fields which were a short walk from the mill. The National Trust has only owned these fields for around eighteen months so not much progress has been made with them yet – they were previously owned by a farmer who lived in a dilapidated house nearby (this also now belongs to the National Trust).
Buying the land was integral to the continuation of conservation projects in the area: due to the close proximity of Manchester airport there were concerns that the fields could have been used for more car parking space, which would have had a significant impact on the flora and fauna living there.
There is a public footpath across the new land and it is now frequently used by dog walkers – apparently people were reluctant to use the path before because of the farmer having a reputation for shooting dogs!
Conducting the survey on these fields was helpful for the National Trust, as they will be able to use the data to identify the best plans for conservation and to monitor changes over the next few years.
One of the main things we had to note down was the type of vegetation.
An example of this can be seen in the picture below; this is known as improved grassland (B4). This means that it has been ploughed up and re-seeded in the past, has been excessively treated with herbicides or fertilisers, or has been heavily grazed by livestock. These actions drastically reduce the biodiversity of an area.
The next pictures show a much more biodiverse field. This has been impacted less by human activity and presents a variety of different habitats – ranging from acid grassland (B1) at the top of the field, sloping down into neutral grassland (B2) in the more low-lying areas. (The ranger who accompanied us told us this, as we were unsure. We could tell that it wasn’t improved grassland due to the greater variance in plant species, but we needed the expert opinion to help us with the rest!)
There were some areas with trees that had to be marked down as well: small numbers of trees are marked down with a dot on the map, but if they cover more than thirty percent of a section of land then they are classed as a woodland. At the bottom of the field in the photograph below we can see an example of a broad-leaved woodland (also known as deciduous woodland – A1.1).
Types of boundary were another important factor – ordinary fencing holds little significance to wildlife but must still be noted (usually drawn on the map), as it can be used to allow livestock to selectively graze a particular area.
Hedges encourage greater biodiversity, but can vary significantly. Intact hedges (J2.1) do not have any gaps and could hold livestock without the need for extra barriers, whilst defunct hedges (J2.2) show large gaps and are incomplete. Defunct hedges usually arise from poor maintenance. Hedges with trees (J2.3) are also noted down.
There were a couple of ponds in the area we surveyed, which of course had to be recorded along with everything else! The ponds we saw were near the improved grassland and the water was discoloured by algae, so they were likely to be eutrophic ponds (G1.1). To determine this properly we should have measured the pH, but we didn’t have the necessary equipment for this on the day.
Once the rough copy of the map had been drawn out in the field, we took it back with us and drew up a proper coloured version. The codes that are used for the data collection are just a temporary measure to speed the process up, and the neat map relies on a series of colour codes.
I hope that you enjoyed this week’s post on Wild Call – it isn’t long until the end of Winter now and I really cannot wait!