Pine Marten Recovery Project, Wales


Despite being listed as a species of “least concern”, the pine marten is scarce in Britain (the current total population is thought to number just 3,500). In the 1800s pine martens were extensively hunted for their fur. This, combined with predator control by gamekeepers and habitat fragmentation, has led them to the verge of extinction in many areas. The Scottish Highlands are the only area where their population still remains strong.

Project brief

Between 2015 and 2017, 51 pine martens were translocated from Scotland to Wales. Ecosulis worked with the Vincent Wildlife Trust to assess the impact of the pine marten reintroduction on local bird biodiversity, using the Biodiversity Quality Calculator (BQC).




manage Biodiversity

Pine marten reintroduction had minimal impact on bird populations.

Protect Habitats

A potential increase in the diversity of habitat structure was noted.

empower-us-to-act People

Informed decision-making enabled regarding further potential reintroduction projects around the UK.

How we added value.

Biodiversity enhancement: pine marten recovery

The reintroduction project began in autumn 2015, when 20 pine martens were relocated from Scotland to Wales, supplementing the remnant population. Second (19 individuals) and third groups (12 individuals) followed one and two years later. The 51 pine martens have since dispersed and are being monitored by the Vincent Wildlife Trust.

Biodiversity valuation: bird data collection

Pine martens feed on nesting birds and eggs, so the reintroduction of pine martens has the potential to affect songbird populations. To test this, bird data from the British Trust for Ornithology (BTO) was processed using Ecosulis’s proprietary Biodiversity Quality Calculator. This had been collected three times in the spring over a 20-year period by recording bird presence along transects in 1 km x 1 km squares. 

Negligible impact on songbird populations

A change in songbird biomass was noted, which could be the result of pine marten predation on large birds such as wood pigeons. No change in the presence or absence of songbirds was observed, and the number of songbird species remained relatively constant throughout the monitoring period.

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