IMIS - Marine Research Groups

Here it is published as a standardized Darwin Core Archive and includes for each sampling event an eventID, date, location and sampling protocol (in the event core), the length of the transect (in the measurement or fact extension) and for each occurrence an occurrenceID, the number of recorded individuals, status (present/absent), life stage, sex, behaviour and scientific name (in the occurrence extension). Issues with the dataset can be reported at https://github.com/inbo/meetnetten-occurrences/issues
Generalized and/or withheld information: as these are sensitive priority species, location information is generalized, in this dataset, to 5 or 10 km Universal Transverse Mercator (UTM) grid cells. Original locations are available upon request.
We have released this dataset to the public domain under a Creative Commons Zero waiver. We would appreciate it if you follow the INBO norms for data use (https://www.inbo.be/en/norms-data-use) when using the data. If you have any questions regarding this dataset, don't hesitate to contact us via the contact information provided in the metadata or via opendata@inbo.be.
For all published Meetnetten.be datasets, see https://www.gbif.org/dataset/search?project_id=meetnetten.be
The target dragonfly species for Meetnetten.be are listed at https://meetnetten.be/#group-6. Other dragonflies observed during the sampling are also included. This dataset covers the population count protocol, for which there are 6 target species.
Sampling was done using the protocol described in De Knijf et al. (2019) and explained to volunteers in Ledegen et al. (2017). Gevlekte witsnuitlibel - Leucorrhinia pectoralis All individuals above a water body or in its immediate vicinity are counted for 1 hour.. The area counts are done at least twice within the peak flight time, with good dragonfly weather, between 11h and 16.30h. A first visit between 20 May and 10 June, a second between 1 and 30 June. Hoogveenglanslibel - Somatochlora arctica All individuals are counted for 1 hour at its larval habitat or in the immediate vicinity .. The area counts are done at least twice within the peak flight time, with good dragonfly weather, between 11h and 16.30h. A first visit between 20 May and 30 June, a second between 1 June and 31 July. Kempense heidelibel - Sympetrum depressiusculum All individuals in a given zone (=area), both near water and surrounding land habitat, are counted for 1 hour. The area counts are done at least twice within the peak flight time, with good dragonfly weather. A first visit between 1 and 10 August, a second between 11 and 31 August. Maanwaterjuffer - Coenagrion lunulatum All individuals above a water body or in its immediate vicinity are counted for 1 hour. The area counts are done at least twice within the peak flight time, with good dragonfly weather, between 11h and 16.30h. A first visit between 20 April and 30 April, a second between 1 May and 20 May. Speerwaterjuffer - Coenagrion hastulatum All adult individuals (i.e., no newly hatched or tenured animals) at the water feature counted for 1 hour. The counts are done at least twice within the peak of the flight time and with good dragonfly weather between 11.00 and 16.30 hrs. A first visit is made between 15 and 31 May, a second between 1 and 20 June.