Background and Aims
Species in intensively used agricultural landscapes face severe disturbance and random destruction, making alternative restoration measures necessary. In Western Europe, Primula vulgaris, a perennial heterostylous herb, is currently restricted to fragmented habitats in farmlands. Translocations were conducted at five locations in a golf course area, using outcrossed juveniles originating from remnant populations. This study aimed to: (1) evaluate the golf course’s contribution to species conservation, (2) assess source population representativeness and (3) determine the impact of translocations on genetic diversity and connectivity of neighbouring populations.

Methods

We conducted a demographic (census size, demographic structure, morph ratio) and genetic (genetic diversity and structure, connectivity network, barrier and parentage analyses) study, using 13 nuclear microsatellite loci across adult and juvenile generations of translocated, adjacent and remote metapopulations, for pre- and post-translocation periods.
Key Results
The translocated golf course populations nearly doubled local census size, provided one-third of the breeders, harboured similar genetic diversity to wild remnant populations of the agricultural area and were representative of source populations. Most populations, even translocated and large ones, were senescent. There was overall genetic erosion over time, threatening long-term population sustainability. Genetic erosion was associated with flowering population size and pin proportion, and was exacerbated in juveniles, suggesting mate limitation and genetic drift effects but also illegitimate pollination. Translocations enhanced contemporary pollen flow and potential connectivity among adjacent populations, although some barriers among remnant populations persisted.

Conclusions
Using recreational infrastructures as alternative sites for translocation of sufficiently large plant numbers, at distances that enable effective pollen flow to integrate new populations into the local network, can contribute to preserve species regional demographic and genetic pools, while increasing connectivity. However, habitat and landscape management of remnant populations remains highly desirable, for safeguarding existing old, still genetically diverse adults, and to guarantee balanced morph ratios and population rejuvenation.