IMIS

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) and for each occurrence an occurrenceID, the number of recorded individuals, status (present/absent) 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 to 1, 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 Caudata species for Meetnetten.be are listed at https://meetnetten.be/#group-1. Other salamanders observed during the sampling are also included. This dataset covers the amphibian chorus counts protocol, for which there are 3 target species.
For the tree frog and spadefoot toad the number of calling males is counted in the reproductive habitat at least twice a year. 1. Male Pelobates fuscus call from the bottom of the waterbody. The calls being fairly weak, counting the exact number of calling males by ear can be challenging. This is particularly the case when other anurans such as Hyla arborea are calling simultaneously. Therefore, the use of an underwater hearing device or hydrophone is advocated. Each waterbody is investigated with waders, in order to approach the calling animals upto hearing distance. 2. Hyla arborea: Monitoring in the framework of the Tree Frog Monitoring Network is done by counting the number of calling males, or in some cases, by estimating the number. 3. For the Natterjack toad monitoring network, calling choruses need to be monitored three times. The number of calling males is counted or in some cases, when the population turns out to be too large, estimated. The number of calling males is counted exactly at each visit. For up to 50 animals the sounds are still good to distinguish and localize so that this is easy (Bauwens & Speybroeck, 2014; Groenveld et al., 2011). With more animals a more rough estimate can be given. Sampling was done using the protocol described in De Bruyn et al. (2015), updated by Speybroeck et al. (2020), and explained to volunteers in Lewylle et al. (2017).