« Back to list of datasets

Long-lasting effects of logging on beetles in hollow oaks


Habitat loss is currently one of the largest threats to biodiversity worldwide, but an increasing number of studies show that accounting for past habitat loss is essential to understanding current distributional patterns. Hollow oaks (Quercus spp.) are important habitats for species that depend on deadwood. We used a gradient spanning 40 km from the coast to inland areas reflecting historical logging intensity through 500 years in Southern Norway, to investigate if the historical variation in oak density is influencing the structure of beetle communities in hollow oaks today. We trapped beetles in 32 hollow oaks along this gradient. The current dataset contains data from 2014, but not 2013 which also was included in the study (and is available through Norway's Species Map Service, http://artskart.artsdatabanken.no). We selected hollow oaks Quercus robur and Q. petraea along a coast-inland gradient in two regions, Agder and Larvik, in southern Norway. Agder is situated in the south, with hollow oaks from the coast to 40 km inland, while Larvik is located in the southeast with hollow oaks from the coast to 25 km inland. We sampled 16 hollow oaks in each region. Our study included trees in forest (n = 17) and semi-natural habitats (n = 15). The latter represents oaks in forest edges along fields or close to settlements. Each oak was sampled for insects using two flight interception traps (window size 20 × 40 cm) for each oak, one in front of the cavity opening and one in the canopy. The insect traps were active from mid-May to mid-August in 2014, and emptied once a month. All beetle species caught were determined to species.