DOI: 10.5061/dryad.5qfttdzjc
title: Scientific and public spider observation records from Sweden

description: This project compares spider biodiversity records from two public citizen
 science platforms, iNaturalist and the Swedish biodiversity database
 Artportalen, and data from a national scientific survey, the Swedish
 Malaise Trap Project (SMTP). The analysis highlights the strengths and
 biases of each source in terms of spatial coverage and species
 representation. Citizen science platforms provide cost-effective and
 large-scale data collection but tend to overrepresent common, easily
 observed species in populated areas. Traditional scientific surveys
 contribute valuable records from rural areas and are especially effective
 at detecting rare and cryptic species. Combining these approaches improves
 our understanding of spider distributions across Sweden and supports more
 comprehensive biodiversity monitoring.
description: This dataset is part of the article “The value of public databases for our
 knowledge of national spider biodiversity compared to a long-term
 scientific monitoring project,” currently under review in the journal
 *Insect Conservation and Diversity*. **Data sources and collection:**
 **SMTP** spider data were collected using Malaise traps as part of a
 nationwide survey conducted between 2003 and 2006. **Artportalen** spider
 observations were retrieved via Analysportalen in May 2024, prior to its
 replacement by Fynddata. All available spider records from Sweden at the
 time of access were included. **iNaturalist** spider observations were
 manually extracted through a direct search in May 2024, filtered to
 include only verifiable records from Sweden. All such observations
 available at the time were included. The dataset includes all the data and
 R-scripts necessary to reproduce the analyses and figures presented in the
 study, with figures 1 and 6 created using QGIS. It contains spider
 observations, species lists, the number of regions (e.g., provinces or
 grid cells) in which each species was recorded, species dominance
 rankings, red list statuses, and measures of recognition and completeness
 of spider families across the three data sources. In addition, it includes
 data on spider observation numbers (from Artportalen) and human population
 density (from Statistics Sweden) for Swedish municipalities and counties.
 The following includes information about all the files in the dataset.
 Please see the descriptions below for details on the contents and purpose
 of each file. **Abbreviations:** **SMTP:** Swedish Malaise Trap Project
 **ARTP:** Artportalen, the Swedish national biodiversity database
 **INAT:** iNaturalist **Explanation of terms:** **Observations:**
 Indicates that a species has been recorded in a collection event,
 regardless of the number of individuals of a species that was observed.
 **Grid cells:** A standardized spatial unit used for mapping and analyzing
 species observations. In this dataset, each grid cell represents a 50 × 50
 km area covering part of Sweden. The entire country is divided into these
 equal-sized cells to facilitate geographic comparisons of species
 distributions. **Occurrence:** denotes the presence of a species within a
 specific grid cell or province. **New occurrence:** refers to the
 observation of a species in a grid cell or province where it had not been
 previously recorded. ### **README: comparison_SMTP_ARTP_fig_2-4.csv** This
 data was used to produce Figures 2–4, which compare SMTP and ARTP data and
 illustrate SMTP’s contribution to the ARTP database, in the following
 order: “Dominance ranks,” “Observation correlation to new occurrences,”
 and “Percentage contributions of spider families.” Data visualizations
 were carried out using the R programming language (version 4.4.0). The
 file “R-scripts” contains the code used to generate these figures, with
 additional explanations provided for each step. **Column Descriptions:**
 **Species:** Scientific name of each spider species collected through the
 SMTP project. **Family:** Taxonomic family to which each species belongs.
 **SMTP_observations:** The total number of observations per species in the
 SMTP project. **ARTP_observations:** The total number of observations per
 species in the ARTP database. **SMTP_rank:** Relative frequency rank of
 each species within the SMTP dataset. A higher rank indicates more
 frequent observations. **Artportalen_rank:** Relative frequency rank of
 each species within the ARTP dataset. A higher rank indicates more
 frequent observations. **SMTP_new_occurrences_grid_cells:** The number of
 new occurrences across grid cells per species in ARTP which were
 contributed by the SMTP project. **ARTP_occurrences_grid_cells:** Total
 number of grid cells in which each species was recorded in ARTP.
 **perc_total_records:** The percentage contribution of occurrences across
 grid cells from the SMTP to the total occurrences of grid cells in
 Artportalen **SMTP_new_occurrences_provinces:** Number of Swedish
 provinces where a species was newly recorded in ARTP due to the SMTP
 project. **Red_list_Sweden:** Conservation status of each species
 according to the Swedish Red List. ### **README:
 completeness_recognition_SMTP_INAT_fig_5.csv** This data was used to
 produce Figure 5, which presents completeness and recognition scores for
 11 common spider families based on INAT observations, as well as the
 effect of including SMTP data on completeness. Data visualizations were
 carried out using the R programming language (version 4.4.0). The file
 “R-scripts” contains the code used to generate the figure, with additional
 explanations provided for each step. **Column Descriptions:** **Family:**
 List of Swedish spider famililes **INAT_observations:** Total number of
 spider observations per family recorded in INAT, regardless of
 identification level. **INAT_to_species_level:** Number of spider
 observations per family recorded in INAT, that were identified to species
 level. **Recognition_INAT:** Proportion of INAT observations that were
 identified to the species level per family (i.e., species-level
 identifications divided by total INAT observations).
 **INAT_number_of_species:** Number of spider species recorded in INAT per
 family. **Completeness_INAT:** Proportion of all known Swedish spider
 species that were recorded in INAT per family. Calculated as:
 INAT_#_of_species /#_of_species_Sweden. **#_of_species_SMTP:** Number of
 spider species recorded in the SMTP per family. **Completeness_SMTP:**
 Proportion of all known Swedish spider species recorded in SMTP per
 family. Calculated as: #_of_species_SMTP / #_of_species_Sweden.
 **Added_species_by_SMTP:** Number of spider species that were found in
 SMTP but not in INAT per family. **#_of_species_INAT_SMTP:** Total number
 of spider species found across both INAT and SMTP combined per family
 (i.e., union of species lists). **Completeness_SMTP_INAT:** Proportion of
 all Swedish spider species captured when combining INAT and SMTP records
 per family. Calculated as: #_of_species_INAT_SMTP / #_of_species_Sweden.
 **#_of_species_ARTP:** Number of spider species recorded in ARTP per
 family. **Completeness_ARTP:** Proportion of all known Swedish spider
 species recorded in ARTP per family. Calculated as: #_of_species_ARTP /
 #_of_species_Sweden. **#_of_species_Sweden:** Total number of spider
 species known to occur in Sweden per family(used as a reference for
 completeness metrics). ### **README: correlation_analysis_dens_obs.csv**
 This data was used for the correlation analysis between population density
 (citizens/km²) of municipalities and spider observations in Sweden. Data
 analysis were carried out using the R programming language (version
 4.4.0). The file “R-scripts” contains the code used to generate the
 analysis, with additional explanations provided for each step. Spider
 observations were retrieved via Analysportalen in May 2024, prior to its
 replacement by Fynddata. All available spider records from Sweden at the
 time of access were included. Population density for municipalities was
 retrieved from Statistics Sweden. **Column Descriptions:**
 **Municipality:** Name of the Swedish municipality in which data were
 collected. **Obs:** Total number of spider observations recorded within
 the municipality. **Density:** Human population density of the
 municipality, typically expressed as the number of people per square
 kilometer. ### **README: correlation_dens_obs_fig_6.csv** This data was
 used to produce Figure 6, which illustrates the correlation between
 county-level population density (citizens/km²) and the number of spider
 observations in Sweden. The figure was generated using QGIS (version
 3.34.14-Prizren). Spider observations were retrieved via Analysportalen in
 May 2024, prior to its replacement by Fynddata. All available spider
 records from Sweden at the time of access were included. Population
 density for counties was retrieved from Statistics Sweden. **Column
 Descriptions:** **Municipality:** Name of the Swedish municipality in
 which data were collected. **Obs:** Total number of spider observations
 recorded within the municipality. **Density:** Human population density of
 the municipality, typically expressed as the number of people per square
 kilometer. ### **README: R_scripts.txt** This file contains all code used
 to generate Figures 2–5, as well as the correlation analysis between human
 population density and the number of spider observations across the
 municipalities of Sweden, using the R programming language (version
 4.4.0). Each step of the script is annotated with explanations describing
 the purpose and function of the code.