Pollinator surveys of two populations located in the North and South of Mallorca (Balearic Islands, Spain) in 2021 from May to July focused on Eryngium maritimum pollinators

The aim of this study is to analyse the role played by E. maritimum in the
dune pollination network of the Balearic Islands, where there is an
intense anthropogenic impact in its habitat. For this purpose, two
populations located in the North and South of Mallorca were chosen, in
which diurnal transects were carried out to observe and capture
pollinators on 15 plant species during the anthesis period of E.
maritimum. The flowering period of 10 plant species flowering at the same
period than E. maritimum was analysed to identify periods of competition
First sampling area was located in Son Serra de Marina (SS, 39.7309N,
3.2382E), in the North of the island.  We carried out three 50m
linear transects along the seashore. Transects were randomly located at a
minimum of 100 m from each other in order to enhance the chances of a fair
sampling of most of the flora. In both areas, vegetation, and so
transects, followed a clear sequence from the seashore inland. Areas were
sampled for 10 weeks, from the beginning of E. maritimum flowering in the
first week of June until the second week of July, plus two weeks extra
(one after and one before) in order two observe pollinator diversity
variation. Surveys took place between 08:00–18:00h under favourable
weather conditions. A pollinator survey involved an observer slowly
walking (40 min) along a transect and recording only those insects that
contacted the plant's reproductive structures while actively
searching for pollen and/or nectar.  The dataset indicates each
observation in a single row. Population, hour, transect, pollinator and
plant taxonomical information, if the pollinator was captured,
photographed or if it visited multiple species is indicated.