As a new addition to the Keystone Habitats team, and ecological work in general, I’m surprised at how much work we deliver alongside larger construction companies, and around their sites. Part of my early journey at Keystone has been realising the importance of these cooperative mitigation projects in protecting wildlife from the path of equally essential works.
I was recently fortunate enough to be part of the team working on our latest mitigation project: the relocation and construction of an artificial otter holt.
At the beginning of the week, we headed down to site to meet with the Principal Ecologist for the project, getting a better look at the works required and preparing ourselves to crack on. Site briefings are essential before starting works, to ensure everyone is fully informed and all systems of work are operating to the safest possible standard.
Wednesday morning arrived and, once briefed, we set to work on site, confident that we could complete the works in the allotted time. After double checking the plans and scanning the area for underground utilities, we marked up our design for the layout and broke ground with the excavator. Before I knew it the layout of the otter holt was taking shape right before my eyes!
- We carved out a 3m x 3m square that was just shy of a meter deep.
- From this square we created two curved tunnels reaching out 2 metres towards the bank of the rhyne. These tunnels would become the entrance points and were curved to avoid sunlight or draught intrusions on the finished holt.
- After some tidying of the hole, we lined the walls of the tunnel and main cavity with natural ash logs secured in place with smaller chestnut stakes.
- This cavity was then divided into four smaller compartments of roughly 60cm x 60cm to mimic the structure of natural otter holts. All passageways were kept to at least 25cm wide so as not to restrict otter movements within.
The holt itself was then covered with a textile sheet to prevent any infill and further topped off with natural timber offcuts for added strength. We then backfilled the hole with existing topsoil and naturalized the area with vegetation we had saved during the initial dig.
The site will eventually become part of a continuous hedgerow along the length of the rhyne, further sheltering it from exposure and creating a secure and safe environment for resident otters to prosper for years to come.
There was a small part of me sad to see our hard work covered up and hidden from view. However, I know the benefits these holts will have, and that’s testament to the pride I felt for the project and how much I learned in the process.
I’m excited to see what projects we have in the pipeline at Keystone and can’t wait for the next one.
Drew Baigent, Habitats Operative
