DOI: 10.5061/dryad.4722kf7
title: Data from: Can opportunistically-collected Citizen Science data fill a data gap for habitat suitability models of less common species?

description: 1. Opportunistically-collected species observations contributed by
 volunteer reporters are increasingly available for species and regions for
 which systematically collected data are not available. However, it is
 unclear if they are suitable to produce reliable habitat suitability
 models (HSMs), and hence if the species-habitat relationships found and
 habitat suitability maps produced can be used with confidence to advice
 conservation management and address basic and applied research questions.
 2. We evaluated HSMs with opportunistically-collected observations against
 HSMs with systematically collected observations. We enhanced the
 opportunistically-collected presence-only data by adding inferred species
 absences. To obtain inferred absences, we asked individual reporters about
 their identification skills and if they reported certain species
 consistently and combined this information with their observations. We
 evaluated several HSM methods using a forest bird species, Siberian jay
 (Perisoreus infaustus), in Sweden: logistic regression with inferred
 absences, two versions of MaxEnt, a model combining presence-absence with
 presence-only observations and a Bayesian site-occupancy-detection model.
 3. All HSM methods produced nationwide habitat suitability maps of
 Siberian jay that agreed well with systematically collected observations
 (AUC: 086-0.88) and were very similar to a habitat suitability map
 produced from the HSM with systematically-collected observations (Spearman
 rho: 0.94-0.98). At finer geographical scales there were differences among
 methods. 4. At finer scale, the resulting habitat suitability maps from
 logistic regression with inferred absences agreed better with results from
 systematically collected observations than other methods. The
 species-habitat relationships found with logistic regression also agreed
 well with those found from systematically collected data and with prior
 expectations based on the species ecology. 5. Synthesis and application:
 For many regions and species, systematically-collected data are not
 available. By using inferred absences from high-quality
 opportunistically-collected contributions of few very active reporters in
 logistic regression we obtained HSMs that produced results similar to
 those from a systematic survey. Adding high-quality inferred absences to
 opportunistically-collected data is likely possible for many less common
 species across various organism groups. Well performing HSMs are important
 to facilitate applications such as spatial conservation planning and
 prioritization, monitoring of invasive species, understanding species
 habitat requirements or climate change studies.
description: All Siberian jay CSD
 presencesPresence observations of
 Siberian jay 2000-2013 (downloaded from https://analysisportal and
 processed according to Appendix S2.) Spatial reference for x and y
 coordinates: EPSG 3021.Siberian jay CSD
 presences of 38 reportersPresence observations of
 Siberian jay 2000-2013 from 38 reporters that consistently reported
 Siberian jay and were able to identify the species by sight and sound
 (downloaded from https://analysisportal and processed according to
 Appendix S2 & S3.) MatchYr 2000: Observations in years 2000-2002;
 MatchYr 2005: Observations in years 2003-2007; MatchYr 2010: Observations
 in years 2008-2013. Spatial reference for x and y coordinates: EPSG
 3021Inferred Siberian jay
 absencesMatchYear 2000:
 Observations in years 2000-2002; MatchYear 2005: Observations in years
 2003-2007; MatchYear 2010: Observations in years 2008-2013. Spatial
 reference for x and y coordinates: EPSG 3021.SBS Siberian Jay
 PresAbsPresence-absence SBS
 data processed according to information in the main text and in Appendix
 S1. MatchYear 2000: Observations in years 2000-2002; MatchYear 2005:
 Observations in years 2003-2007; MatchYear 2010: Observations in years
 2008-2013. PA: 1 denotes presence, 0 denotes absence. Quarter gives the
 location of the observation unit within each SBS survey route: SW:
 south-west, NW: north-west, NE: north-east, SE: south-east. Karta is the
 survey route identifier. For further information about the SBS:
 http://www.fageltaxering.lu.seHazel grouse CSD
 presencesPresence observations of
 Hazel grouse 2000-2013 (downloaded from https://analysisportal and
 processed according to Appendix S2). Spatial reference for x and y
 coordinates: EPSG 3021.Grey-headed woodpecker
 CSD presencesPresence observations of
 Grey-headed woodpecker 2000-2013 (downloaded from https://analysisportal
 and processed according to Appendix S2). Spatial reference for x and y
 coordinates: EPSG 3021.Lesser spotted
 woodpecker CSD presencesPresence observations of
 Lesser spotted woodpecker 2000-2013 (downloaded from
 https://analysisportal and processed according to Appendix S2). Spatial
 reference for x and y coordinates: EPSG 3021.Three-toed woodpecker
 CSD presencesPresence observations of
 Three-toed woodpecker 2000-2013 (downloaded from https://analysisportal
 and processed according to Appendix S2). Spatial reference for x and y
 coordinates: EPSG 3021.Siberian tit CSD
 presencesPresence observations of
 Siberian tit 2000-2013 (downloaded from https://analysisportal and
 processed according to Appendix S2). Spatial reference for x and y
 coordinates: EPSG 3021.Red-breasted flycatcher
 CSD presencesPresence observations of
 Red-breasted flycatcher 2000-2013 (downloaded from https://analysisportal
 and processed according to Appendix S2). Spatial reference for x and y
 coordinates: EPSG 3021.Long-tailed tit CSD
 presencesPresence observations of
 Long-tailed tit 2000-2013 (downloaded from https://analysisportal and
 processed according to Appendix S2). Spatial reference for x and y
 coordinates: EPSG 3021.Inferred Grey headed
 woodpecker absencesInferred absences for
 Grey headed woodpecker. MatchYear 2000: Observations in years 2000-2002;
 MatchYear 2005: Observations in years 2003-2007; MatchYear 2010:
 Observations in years 2008-2013. Spatial reference for x and y
 coordinates: EPSG 3021.Inferred Hazel grouse
 absencesInferred absences for
 Hazel grouse. MatchYear 2000: Observations in years 2000-2002; MatchYear
 2005: Observations in years 2003-2007; MatchYear 2010: Observations in
 years 2008-2013. Spatial reference for x and y coordinates: EPSG
 3021.Inferred Lesser spotted
 woodpecker absencesInferred absences for
 lesser spotted woodpecker. MatchYear 2000: Observations in years
 2000-2002; MatchYear 2005: Observations in years 2003-2007; MatchYear
 2010: Observations in years 2008-2013. Spatial reference for x and y
 coordinates: EPSG 3021.Inferred Long tailed tit
 absencesInferred absences for
 long tailed tit. MatchYear 2000: Observations in years 2000-2002;
 MatchYear 2005: Observations in years 2003-2007; MatchYear 2010:
 Observations in years 2008-2013. Spatial reference for x and y
 coordinates: EPSG 3021.Inferred Red breasted
 flycatcher absencesInferred absences for
 red-breasted flycatcher. MatchYear 2000: Observations in years 2000-2002;
 MatchYear 2005: Observations in years 2003-2007; MatchYear 2010:
 Observations in years 2008-2013. Spatial reference for x and y
 coordinates: EPSG 3021.Inferred Siberian tit
 absencesInferred absences for
 Siberian tit. MatchYear 2000: Observations in years 2000-2002; MatchYear
 2005: Observations in years 2003-2007; MatchYear 2010: Observations in
 years 2008-2013. Spatial reference for x and y coordinates: EPSG
 3021.Inferred Three-toed
 woodpecker absencesInferred absences for
 three-toed woodpecker. MatchYear 2000: Observations in years 2000-2002;
 MatchYear 2005: Observations in years 2003-2007; MatchYear 2010:
 Observations in years 2008-2013. Spatial reference for x and y
 coordinates: EPSG 3021.