Fragmented grasslands in different landscape structures provide different opportunities for cavity-nesting Hymenoptera

This dataset accompanies the manuscript entitled “Fragmented grasslands in different landscape structures provide different opportunities for cavity-nesting Hymenoptera.” The study investigates how fragment size, landscape connectivity, and local floral resources influence cavity-nesting Hymenoptera communities in semi-natural grasslands of the Great Hungarian Plain (Pannonian forest-steppe region, Hungary). Data were collected from 60 grassland fragments distributed along gradients of fragment size and isolation. Thirty sites were sand steppes embedded primarily in forest-dominated landscapes, and thirty were loess steppe fragments embedded in agricultural landscapes.