Wild Frontier Ecology (WFE) was commissioned to monitor invertebrates at a new wind farm in Northamptonshire as part of the site’s post-construction monitoring. To analyse the diverse insect samples collected, WFE used NatureMetrics’ invertebrate metabarcoding service.

From just ten samples, we identified 144 unique taxa, the majority to species level. The results gave WFE a clear picture of the invertebrate communities in the grassland field margins managed under the site’s Habitat Improvement Plan, and a dataset that can be built on in every future survey year.

WFE’s brief was to survey terrestrial invertebrates after the wind farm was built, with sampling prescribed in years 1, 3, 6 and 9 following construction, and surveys in the second and third quarters of each year.

The team needed to:

• Assess the condition of the grassland field margins managed under the site’s Habitat Improvement Plan
• Deliver consistent invertebrate monitoring across a long-term, multi-year programme
• Trial DNA metabarcoding as an efficient way to analyse the diversity of bulk insect samples

WFE selected five survey locations to capture variation across the grassland habitat. At each point, a flying insect trap was set up, with three pitfall traps placed one metre away in a triangle formation.

The samples were sent to our lab and processed through our ‘invertebrate identification from bulk sample’ pipeline. Each sample was ground into a fine powder, then its DNA was extracted, amplified and sequenced. Our in-house bioinformaticians processed the sequences and matched them against a DNA reference library of UK invertebrate species to assign taxonomy.

We returned the results to WFE in a clear, easy-to-read report.

In total, we identified 144 unique taxa from the ten samples. The majority (88%) were identified to species level, with the remainder assigned to genus or family. The samples collected in June and September showed clearly different taxonomic compositions, as the summary data below shows.

Diptera (flies) and Coleoptera (beetles) were the dominant groups in both months, while Heterobranchia (slugs and snails) and Collembola (springtails) were much more abundant in September than in June.

Alongside summary charts like the one below, our report included a species-by-sample table in Excel format. This can be updated as each new set of samples is processed and used for more complex community analyses.

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The results gave WFE species-level evidence to assess the condition of the site’s managed grassland margins, and a baseline to compare against in years 3, 6 and 9. The trial also showed that DNA metabarcoding can identify most taxa in mixed bulk samples to species level, producing a dataset WFE can add to with every survey round.

The impact text still assumes this was the first survey year. If it wasn’t, change “years 3, 6 and 9” to “future survey years”. I’ve updated the draft in the project to match.