MICA - Muskrat occurrences collected in West Flanders, Belgium

Study Extent

Muskrats were introduced in 1928 in Belgium as a fur animal. As early as 1938, its eradication was ordered, making the muskrat control program one of the longest standing control programs for any organism in Belgium. Since then, there have been many different actors and control methods, and today the control is still spread over several management actors and public authorities. In 1991 control was organized at the municipal level, many of whom hired private firms to control muskrats (Stuyck 2002). Catches, bait use, effort and bycatches (most of the time) were submitted monthly to Landelijke Waterdienst /AMINAL - afdeling Water by mail. Muskrat control in Flanders was regionalized and strongly professionalized at the end of the 1990s. For-profit trapping and the fur trade of muskrats was banned. The Flanders Environment Agency (VMM) became responsible for controlling muskrats on all streams under Flemish regional jurisdiction. They are complemented by other management actors, such as provincial and municipal trappers, Rattenbestrijding Oost-Vlaanderen (RATO vzw) and Polders and Wateringen (vvpw).

Sampling

Before 2000, baits infused with rodenticides were used to control muskrats. These catches were seldom registered as animals could not be recovered. It is therefore likely that reported catches up until this point in time are an underestimation. Since 2000, Flanders has banned the use of rodenticides for muskrat control and the control is performed purely mechanical using various types of traps. These traps will be laid out either at fixed distances close to the regional borders as a passive control mechanism or they will be placed where traces of muskrat presence are reported as active control mechanisms (Verbeylen et al. 2002). These traps are controlled minimally each week but at high densities it is more likely that a trapper will check them each day. The date of an observation is therefore the date that the animal was retrieved from the trap.This is explained in Dwc:samplingEffort Trapping techniques used in Flanders are described in the best practice of Stuyck (2016). Conibeartraps, fishtraps and baittraps are used for this dataset. RATO vzw carries out active control on the public areas in East Flanders. The trapper searches along the public waterways, street canals, container parks... to find traces of muskrats and brown rats. The transitions of closed to open sewer are extra guarded.

Quality Control

see step description

Method steps

1. Source data are submitted by the different management actors on either a monthly or yearly basis. Initially these submission where done by mailing the monthly numbers which were then digitized in Excel spreadsheet. Since the early 2000s all management actors have switched to submitting their catches in Excel spreadsheets.
2. An export of the masterdata originating from the province of West Flanders was received (https://github.com/inbo/muskrat-occurrences).
3. We developed a Rmarkdown script to document and perform the transformation of the data to Darwin Core, which includes the following steps:
4. Perform some basic data cleaning of the raw data.
5. Create an occurrence core file (http://rs.gbif.org/core/dwc_occurrence_2015-07-02.xml) for presence-only and all data.
6. The Darwin Core data file is uploaded to the INBO IPT and documented with metadata.
7. The dataset is published and registered with GBIF.

Ondatra zibethicus (muskrat)

1. Animalia
   rank: kingdom
2. Ondatra zibethicus
   rank: species

Province of West Flanders, Belgium