A database of threat statuses and life-history traits of Red List species in Flanders (northern Belgium)

Abstract Background Red Lists estimate the extinction risk of species at global or regional levels and are important instruments in conservation policies. Global Red List assessments are readily available via the IUCN website (https://www.iucnredlist.org) and are regularly updated by (taxonomic) experts. Regional Red Lists, however, are not always easy to find and often use local criteria to assess the local extinction risk of species. New information Here, we publish a database with the outcome of 38 Red List assessments in Flanders (northern Belgium) between 1994 and 2018. In total, the database contains 6,224 records of 5,039 unique taxa pertaining to 24 different taxonomic groups. Using a quality control procedure, we evaluated the criteria used, the number of records, the temporal and spatial distribution of the data and the up-to-dateness of the Red Lists. This way, nineteen Red Lists were approved as being of sufficient high quality (i.e. validated) and nineteen others were not. Once validated, Red Lists are approved by the regional Minister of Environment and published in the Belgian Official Gazette acquiring legal status. For the validated Red Lists, we additionally compiled (life-history) traits that are applicable to a wide variety of species groups (taxonomic kingdom, environment, biotope, nutrient level, dispersal capacity, lifespan and cuddliness). The publication of this dataset allows comparison of Red List statuses with other European regions and countries and permits analyses about how certain (life-history) traits can explain the Red List status of species. The dataset will be regularly updated by adding new Red List (re)assessments and/or additional (life-history) traits.


Introduction
Red Lists are important instruments at both the global and the regional scale (Brooks et al. 2016). They estimate the extinction risk in a given region, usually using standardised and internationally accepted criteria (Mace et al. 2008). Although Red Lists are not compiled to prioritise conservation actions (Lamoreux et al. 2003, Rodrigues et al. 2006, they are often used as an important source for conservation policies (McCarthy et al. 2008), such as species action plans (Fitzpatrick et al. 2007, Laycock et al. 2011) and reintroduction programmes (IUCN/SSC 2013). Additionally, consecutive Red Lists allow comparison of changes in Red List categories and, in combination with information on threats, provide information about effective application of conservation efforts to the species' major threats (Brooke et al. 2008). Yet, national or regional Red Lists are often only available locally and/ or in the local language and not always easy to access, which hinders analyses on larger scales (Maes et al. 2019). Although a website with national or regional Red Lists exists (htt p://www.nationalredlist.org), it is often more convenient for local authorities to manage the information on national or regional Red Lists locally (e.g. https://www.inbo.be/en/searchflanders-red-lists) and to publish them on open-access platforms for easier availability.
Here, we publish the results of Red List assessments in Flanders (northern Belgium) between 1994 and 2018. For the species on the validated Red Lists, we also include some general (life-history) traits (taxonomic kingdom, environment, biotope use, nutrient level, lifespan, mobility and cuddliness -cf. Trochet et al. 2014), which allows further analyses on the correlation between the Red List status and the species characteristics (cf. Jeppsson and Forslund 2014).

General description
Purpose: This database publishes the Red List statuses of all species that were assessed in Flanders (northern Belgium) since 1994. First, a literature search was done in both local and scientific publications to gather all Red List assessments ever performed in Flanders. All species present in the Red Lists were compiled in a database with the original taxonomic name and Red List status as published in the original Red List. The data were carefully checked for double entries and for typing errors in the published species names. Since Red List categories were not always in accordance with the presently-used IUCN categories, we ''translated'' the originally-published Red List category into IUCN Red List categories. Second, all species names were checked against the GBIF Backbone Taxonomy (GBIF secretariat 2019) to obtain currently traceable species names (including synonyms). Since the Flemish Species Decree of 2009 (Flemish Government 2009) came into effect, Red List assessments in Flanders are coordinated by the Research Institute for Nature and Forest (INBO, formerly the Institute for Nature Conservation -IN). The task of the Institute is to not only instigate the compilation of new Red Lists, but also to perform a control procedure to check whether the Red List is of sufficiently high quality. The quality control procedure consists of checking the number of available historical and recent data, the number of sites that were surveyed in both historical and recent times (>70 grid cells of 5 x 5 km) and a minimal spatial coverage (>10%) of the different ecological districts of Flanders . For older Red Lists, this quality control was done post factum, while for new Red Lists, this was done at the start of the Red List assessment. Red Lists fulfilling the quality control criteria are labelled as ''validated Red Lists''. Applying this procedure, we were able to validate nineteen out of 38 published Red Lists Table 1    Finally, we added (life-history) traits (kingdom, environment, biotope, nutrient level, lifespan, mobility and cuddliness) to the species in the validated Red Lists based on regional sources on the biology and/or ecology of the different species groups (see references in Table 1). These life-history traits are explained in Tables 5, 6 , 7, 8, 9, 10, 11. The workflow for the compilation of the Red List database in Flanders is given in Fig. 1.  The taxonomic kingdom to which the different species groups belong.

Eutrophic
The biotope in which the species occurs has a high nutrient level

Mesotrophic
The biotope in which the species occurs has an intermediate nutrient level

Oligotrophic
The biotope in which the species occurs has a low nutrient level

Longlived
The species lives ≥ 3 years

Mobile
The dispersal capacity of the species is ≥ 5 km

Sedentary
The dispersal capacity of the species is < 5 km Table 7.
The biotope type in which each species occurs. Table 8.
The nutrient level of the biotope in which each species occurs. Table 9.
The lifespan of each species .   Table 10.
The dispersal capacity of each species.

Cuddly
The species is considered cuddly Non cuddly The species is considered non-cuddly (spiny, dangerous, venomous, predator) We will update the database regularly, i.e. whenever new Red Lists are published and/or new information on the life-history traits of the assessed species becomes available. We also aim to reassess all Red Lists (using IUCN criteria) of taxonomic groups for which only local criteria were applied in the past (e.g. carabid beetles, dragonflies, vascular plants).

Additional information:
Red Lists are usually published as reports from the Research Institute for Nature and Forest (INBO), but some of them remained unpublished and were only available for internal use (waterbeetles -Bosmans 1994, waterbugs -Bosmans 1994Bonte et al. 2001, hoverflies -Meerhaeghe and Grootaert 1998, land snails -van Loen et al. 2006. Other Red Lists were published as part of (provisional) distribution atlases (amphibians and reptiles -Bauwens and Claus 1996, freshwater fishes - Vandelannoote and Coeck 1998, grasshoppers -Decleer et al. 2000, ants -Dekoninck et al. 2003, breeding birds -Devos et al. 2004, dragonflies -De Knijf 2006, vascular plants -Van Landuyt et al. 2006, as dissertation projects (waterbeetles -Scheers 2012) or as papers in local (spiders -Maelfait et al. 1998, waterbugs -Lock et al. 2013 or international journals (butterflies - , freshwater fishes -Verreycken et al. 2014, ladybirds -Adriaens et al. 2015. In this database, we bring together all the threat statuses of all the species mentioned in the published and unpublished Red Lists since 1994 in Flanders. Table 11.
The cuddliness of each species.

Figure 1.
Workflow for the compilation of the Red List database in Flanders (northern Belgium).
Since 1994, 38 Red Lists have been compiled in Flanders. In total, this concerned 6,224 records of 5,039 unique species -in some cases listed in consecutive Red Listspertaining to 24 taxonomic groups. Most of the older Red Lists (1994)(1995)(1996)(1997)(1998)(1999) used expert judgement without quantitative analyses to classify species into Red List categories: mammals (Criel 1994), waterbugs (Bosmans 1994), waterbeetles (Bosmans 1994), spiders (Maelfait et al. 1998) and breeding birds (Devos and Anselin 1999). After the publication of local Red List criteria , Red Lists were compiled using a combination of rarity and decline (Maes and van Swaay 1997). Since 2011, however, IUCN criteria for regional use (IUCN 2003) were adopted in Flanders ) and since then, all Red Lists were compiled using the IUCN criteria. The main difference between local and IUCN criteria is that IUCN criteria allow species to be classified based on declining trends (criterion A), rarity or small population sizes only (criterion B, C or D), while in the previously used local criteria, a species could only be classified as threatened when it had both a declining (distribution or population) trend and when the species had a limited distribution.

Geographic coverage
Description: Flanders covers an area of 13,522 km² and is the northern administrative region of Belgium Fig. 2  The location of Flanders (in black) within Belgium (in grey) in NW Europe. The white area within Flanders is the Brussels-Capital Region.

RLCAsPublished and RLC_IUCN
The Red List category as published (RLCAsPublished) in the original Red Lists, mostly in Dutch, are given in Table 3, as well as their translation into the Red List category (RLC_IUCN) according to the IUCN Red List categories (IUCN 2003). Depending on the Red List categories used, the original Red List categories can be translated into different IUCN categories and vice versa.

Criteria
The criteria used to compile the Red Lists (Table 4).

Kingdom
The taxonomic kingdom to which a species belongs (Fungi, Invertebrates, Plants, Vertebrates - Table 5).

Environment
The environment in which the species occurs (Aquatic, Epiphytic, Marine, Semi-aquatic, Terrestrial - Table 6).

Biotope
The preferred biotope in which the species occurs in Flanders (northern Belgium) ( Table 7). This is based on broad biotope classifications used in the land use map of Flanders (Gobin et al. 2009) and in Corine Land Cover (Version 18.5.1) or Natura2000 habitats (Council Directive 92/43/EEC). For species occurring in two different biotope types, both biotopes are given in the dataset.

NutrientLevel
The nutrient level of the biotope in which the species occurs (Eutrophic, Mesotrophic, Oligotrophic - Table 8).

Lifespan
The longevity of the species (Table 9). We arbitrarily choose 3 years to discriminate between longlived and shortlived species.

Mobility
The dispersal capacities of the species (Table 10) We arbitrarily choose 5 kilometres to discriminate between mobile and sedentary species.

Cuddliness
Whether the species is considered cuddly or not (Stokes 2007) (Table 11). This information is only given for animals (invertebrates and vertebrates).

Temporal coverage
Notes: All Flemish Red Lists compiled between 1994 and 2018.   for Red List assessment. Here, this compilation is published as a standardised Darwin Core Archive and includes for each taxon: the scientific name, higher classification (provided by the GBIF Backbone Taxonomy, http s://doi.org/10.15468/39omei), stable taxon identifier and Dutch vernacular name (in the taxon core), the Red List category in Flanders as published, its IUCN equivalent and year of assessment (respectively, in occurrenceRemarks, threatStatus and eventDate in the distribution extension) and the life-history traits environment, biotope, cuddliness, lifespan, mobility, nutrient level and spine (in the description extension). Issues with the dataset can be reported at: https://github.com/inbo/rl-flanders-checklist.