Biodiversity Data Journal :
Data Paper (Biosciences)
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Corresponding author: Fernanda Alves-Martins (ferfealvesmartins@gmail.com)
Academic editor: Ricardo Moratelli
Received: 12 Jul 2024 | Accepted: 15 Aug 2024 | Published: 05 Sep 2024
© 2024 Ana Filipa Palmeirim, Ana Catarina Araújo-Fernandes, Ana Sofia Castro-Fernandes, Patricia Guedes, José Cassari, Vanessa A. Mata, Natalie Yoh, Ricardo Rocha, Javier Martínez-Arribas, Fernanda Alves-Martins
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Palmeirim AF, Araújo-Fernandes AC, Castro-Fernandes AS, Guedes P, Cassari J, Mata VA, Yoh N, Rocha R, Martínez-Arribas J, Alves-Martins F (2024) Insectivorous bat activity dataset across different land-use types in the Islands of São Tomé and Príncipe, Central West Africa. Biodiversity Data Journal 12: e131955. https://doi.org/10.3897/BDJ.12.e131955
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São Tomé and Príncipe oceanic islands, in Central West Africa, are characterised by exceptional levels of endemism. Since human colonisation in the mid-15th century, São Tomé and Príncipe have lost 74% and 67% of their native habitat, respectively. Today, these islands are mainly covered by remaining old-growth forests, secondary regrowth forests, shaded plantations (mostly of cocoa), oil palm plantations (in the case of São Tomé), small-scale agricultural areas and urban areas. Yet, little is known about how species on these islands are coping with land-use changes. Island ecosystems are particularly important for bats, with about 25% of the world’s bat species being entirely restricted to island systems. São Tomé and Príncipe Islands comprise six and four native insectivorous bats, respectively. Two species, Chaerephon tomensis and Macronycteris thomensis, are island-endemics in São Tomé; Pseudoromicia principis is an island-endemic in Príncipe; and Miniopterus newtoni is endemic from both São Tomé and Príncipe. Here, we present a dataset comprising a comprehensive compilation of occurrence records derived from acoustic sampling of insectivorous bats across the predominant land-use types of both the São Tomé and Príncipe Islands. In each sampling site, standardised surveys consisted of deploying one Audio Moth device that recorded for 1 minute every 5 minutes over a 48-hour period. We identified a total of 19,437 bat-passes across the 115 sites surveyed in São Tomé Island and 17,837 bat-passes across the 50 sites surveyed in Príncipe Island.
Based on a sampling effort of 1,584 hours of recordings manually processed to identify all the contained bat passes, this dataset, publicly available on GBIF, provides comprehensive information on the activity of insectivorous bats across two endemic-rich oceanic islands in the Gulf of Guinea. For each bat pass identified, we report the identified species, geographic coordinates, land-use type, altitude, date and time. This is the first public dataset providing detailed information on species-level habitat use for insectivorous bats on oceanic islands in Africa.
Chiroptera, Gulf of Guinea, habitat modification, tropical forests, oceanic islands, passive acoustic monitoring
Oceanic islands comprise important areas for biodiversity conservation, often harbouring a greater number of endemic species compared to equivalent mainland areas (
Island ecosystems are particularly important for bats, with ca. 25% of global bat species being entirely restricted to island systems (
Located off the western equatorial coast of Central Africa, São Tomé and Príncipe Islands are part of the three oceanic islands that arose as part of the Cameroon Volcanic Line comprising the Gulf of Guinea (
In addition to the endemics, three insectivorous native bat species are common to both islands. The molossid Chaerephon pumilus (Cretzschmar, 1826) is known to forage in open spaces and to roost within cracks in rocks or trees, as well as in buildings (
Since human colonisation in the mid-15th century, anthropogenic land-uses have significantly transformed the native landscapes in São Tomé and Príncipe (
The study was conducted in São Tomé and Príncipe, a democratic state comprising two main islands (São Tomé and Príncipe), as well as several smaller islets. This nation is located in the Gulf of Guinea, off the western equatorial coast of Central Africa (Fig.
Tropical forests in São Tomé and Príncipe fall within the ecoregion of São Tomé and Príncipe moist lowland forests. Both islands comprise the Ôbo Natural Park, a significant conservation area established that covers ca. 235 km2 in São Tomé (27% of the island area) and 65 km2 in Príncipe (46%) (
Both islands are occupied by a number of habitat types encompassing a range of human disturbance intensities, including old-growth forests, regrowth forests, shaded plantations, oil-palm plantations (only in São Tomé Island), agricultural areas and urban areas. This dataset includes a compilation of insectivorous bat records obtained across each of these habitats throughout each of the islands (Fig.
Acoustic surveys targeting insectivorous bats were carried out between August and September 2022, during the dry season. The sampling period was chosen to avoid severe storms typical of the region, preventing rain-induced deterioration of acoustic recordings and ensuring accurate detection of bat activity, which tends to decrease during heavy rain due to reduced insect activity and echolocation interference (
Number of sampling sites where insectivorous bats were surveyed per land-use type in both São Tomé and Príncipe Islands.
Land-use types |
São Tomé Island |
Príncipe Island |
Old-growth forests |
13 |
11 |
Secondary re-growth forests |
17 |
13 |
Shaded plantations |
29 |
15 |
Oil palm plantations |
20 |
- |
Agricultural areas |
23 |
9 |
Urban areas |
13 |
2 |
Each sampling site was surveyed by deploying one Audio Moth recorder (
Using Kaleidoscope Version 5.4.7 (Wildlife Acoustics, USA), we first split the recordings into five-second WAV files (
A total of 115 and 50 sampling sites were set up in the São Tomé and Príncipe Islands, respectively. Sampling covered all the predominant land-use types on both islands.
Coordinates: Minimum Latitude: 0.029; Maximum Latitude: 1.698; Minimum Longitude: 6.502; Maximum Longitude: 7.457
São Tomé and Príncipe Islands comprise six and four insectivorous bats, respectively, with the two species, Chaerephon tomensis and Macronycteris thomensis, being island-endemics in São Tomé and Pseudoromicia principis being an island-endemic in Príncipe. We recorded a total of 19,437 bat passes across the 115 sites surveyed on São Tomé Island and 17,837 bat passes across the 50 sites surveyed on Príncipe Island (Table
Insectivorous bat list species in São Tomé and Príncipe Islands, Central West Africa. Chaerephon spp. corresponds to cases in which C. pumilus and C. tomensis could not be distinguished due to overlap in these species’ echolocation call parameters.
Family |
Scientific name |
Location |
Number of bat passes recorded |
Emballonuridae |
Taphozous mauritianus E.Geoffroy, 1818 |
São Tomé Island |
23 |
Emballonuridae |
Taphozous mauritianus E.Geoffroy, 1818 |
Príncipe Island |
7 |
Hipposideridae |
Hipposideros ruber (Noack, 1893) |
São Tomé Island |
129 |
Hipposideridae |
Hipposideros ruber (Noack, 1893) |
Príncipe Island |
48 |
Hipposideridae |
Macronycteris thomensis (Bocage, 1891) |
São Tomé Island |
632 |
Miniopteridae |
Miniopterus newtoni Bocage, 1889 |
São Tomé Island |
7,900 |
Molossidae |
Chaerephon Dobson, 1874 |
São Tomé Island |
1,686 |
Molossidae |
Chaerephon pumilus (Cretzschmar, 1826) |
São Tomé Island |
9,067 |
Molossidae |
Chaerephon pumilus (Cretzschmar, 1826) |
Príncipe Island |
2,513 |
Vespertilionidae |
Pseudoromicia principis (Juste, Torrent, Méndez-Rodríguez, Howard, García-Mudarra, Nogueras & Ibáñez, 2023) |
Príncipe Island |
15,269 |
Species-specific maps showing the distribution of each species within São Tomé and Príncipe Islands: Taphozous mauritianus in A São Tomé and in B Príncipe; Hipposideros ruber in C São Tomé and in D Príncipe; E Macronycteris thomensis in São Tomé; F Miniopterus newtoni in São Tomé; G Chaerephon spp. in São Tomé; Chaerephon pumilus in H São Tomé and in I Príncipe; and J Pseudoromicia principis in Príncipe. Each point denotes a sampling site where the corresponding species has been recorded. Points are scaled according to the species-specific bat activity recorded (number of bat passes).
Rank | Scientific Name |
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species | Taphozous mauritianus |
species | Hipposideros ruber |
species | Macronycteris thomensis |
species | Miniopterus newtoni |
genus | Chaerephon spp. |
species | Chaerephon pumilus |
species | Pseudoromicia principis |
This dataset provides comprehensive information on the activity of insectivorous bats across different land-use types on the Islands of São Tomé and Príncipe. Acoustic surveys targeting insectivorous bats were carried out in August and September 2022, during the dry season. To ensure data representation for each of the major land-use types present on the Islands, sampling sites were stratified according to the availability of each land-use type. In total, we surveyed 115 sites on São Tomé and 50 sites on Príncipe. Each sampling site was surveyed by deploying one AudioMoth recorder programmed to record for one minute every five minutes, for two consecutive days and nights, totalling 240 minutes of active recording per day. For each bat pass identified, we report the species, geographic coordinates, land-use type, altitude, date and time.
Column label | Column description |
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InstitutionID (event core) | An identifier for the institution having custody of the object(s) or information referred to in the record. |
institutionCode (event core) | The name (or acronym) in use by the institution having custody of the object(s) or information referred to in the record. |
ownerInstitutionCode (event core) | The name (or acronym) in use by the institution having ownership of the object(s) or information referred to in the record. |
basisOfRecord (occurrence extension) | The specific nature of the data record. |
dynamicProperties (event core) | A list of additional measurements, facts, characteristics or assertions about the record. T: number of trees; HT: average of five highest trees; St: number of stems; L: number of lianas; P: number of palm or coconut trees; C: canopy cover; veg_0: vegetation cover at 0 m; veg_1: vegetation cover at 1 m; veg_2: vegetation cover at 2 m; veg_4: vegetation cover at 4 m; veg_8: vegetation cover at 8 m; veg_16: vegetation cover at 16 m; veg_32vegetation cover at 32 m. |
occurrenceID (occurrence extension) | An identifier for the dwc:Occurrence (as opposed to a particular digital record of the dwc:Occurrence). |
recordedBy (occurrence extension) | A list (concatenated and separated) of names of people, groups or organisations responsible for recording the original dwc:Occurrence. |
individualCount (occurrence extension) | The number of individuals present at the time of the dwc:Occurrence. |
organismQuantityType (occurrence extension) | A number or enumeration value for the quantity of dwc:Organisms. |
occurrenceStatus (occurrence extension) | A statement about the presence or absence of a dwc:Taxon at a dcterms:Location. |
eventID (event core, occurrence extension) | An identifier for the set of information associated with a dwc:Event. In this case, a sampling site. |
parentEventID (event core) | An identifier for the broader dwc:Event that groups this and potentially other dwc:Events. In this case, a broader category for a sampling site. STA: São Tomé Agricultural area; STO: São Tomé Palm Oil plantation; STP: São Tomé old growth forest; STR: São Tomé Regrowth forest; STS: São Tomé shaded plantation; STU: São Tomé urban area; PA: Príncipe Agricultural area; PP: Príncipe old growth forest; PR: Príncipe Regrowth forest; PS: Príncipe Shaded plantation; PU: Príncipe Urban area. |
eventDate (event core, occurrence extension) | The date-time or interval during which a dwc:Event occurred. For occurrences, this is the date-time when the dwc:Event was recorded. |
habitat (event core) | A category or description of the habitat in which the dwc:Event occurred. |
samplingProtocol (event core) | The names of, references to, or descriptions of the methods or protocols used during a dwc:Event. |
sampleSizeValue (event core) | A numeric value for a measurement of the size (time duration, length, area or volume) of a sample in a sampling dwc:Event. |
sampleSizeUnit (event core) | The unit of measurement of the size (time duration, length, area or volume) of a sample in a sampling dwc:Event. |
samplingEffort (event core) | The amount of effort expended during a dwc:Event. |
continent (event core) | The name of the continent in which the dcterms:Location occurs. |
island (event core) | The name of the island on or near which the dcterms:Location occurs. |
countryCode (event core) | The standard code for the country in which the dcterms:Location occurs. |
decimalLatitude (event core) | The geographic latitude (in decimal degrees, using the spatial reference system given in dwc:geodeticDatum) of the geographic centre of a dcterms:Location. |
decimalLongitude (event core) | The geographic longitude (in decimal degrees, using the spatial reference system given in dwc:geodeticDatum) of the geographic centre of a dcterms:Location. |
identifiedBy (occurrence extension) | A list (concatenated and separated) of the globally unique identifier for the person, people, groups or organisations responsible for assigning the dwc:Taxon to the subject. |
scientificName (occurrence extension) | The full scientific name, with authorship and date information if known. When forming part of a dwc:Identification, this should be the name in lowest level taxonomic rank that can be determined. |
kingdom (occurrence extension) | The full scientific name of the kingdom in which the dwc:Taxon is classified. |
phylum (occurrence extension) | The full scientific name of the phylum or division in which the dwc:Taxon is classified. |
class (occurrence extension) | The full scientific name of the class in which the dwc:Taxon is classified. |
order (occurrence extension) | The full scientific name of the order in which the dwc:Taxon is classified. |
family (occurrence extension) | The full scientific name of the family in which the dwc:Taxon is classified. |
genus (occurrence extension) | The full scientific name of the genus in which the dwc:Taxon is classified. |
taxonRank (occurrence extension) | The taxonomic rank of the most specific name in the dwc:scientificName. |
eventTime (occurrence extension) | The time or interval during which a dwc:Event occurred. |
organismQuantity (occurrence extension) | A number or enumeration value for the quantity of dwc:Organisms. |
geodeticDatum (event core) | The ellipsoid, geodetic datum or spatial reference system (SRS), upon which the geographic coordinates given in dwc:decimalLatitude and dwc:decimalLongitude are based. |
coordinateUncertaintyInMetres (event core) | The horizontal distance (in metres) from the given dwc:decimalLatitude and dwc:decimalLongitude describing the smallest circle containing the whole of the dcterms:Location. |
country (event core) | The name of the country or major administrative unit in which the dcterms:Location occurs. |
minimumElevationInMetres (event core) | The lower limit of the range of elevation (altitude, usually above sea level), in metres. |
maximumElevationInMetres (event core) | The upper limit of the range of elevation (altitude, usually above sea level), in metres. |
ASF, ACF, PG, RR, FA-M, JM-A and AFP were supported by the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement No 854248 (TROPIBIO). This Programme further funded the fieldwork. VAM was supported by Fundação para a Ciência e a Tecnologia (FCT) through an individual research contract (DOI: 10.54499/2020.02547.CEECIND/CP1601/CT0006). We thank the Direction of Forests and Biodiversity of São Tomé and Príncipe for authorising the surveys. We thank BirdLife International São Tomé and Princípe Initiative, Associação Monte Pico and Fundação Príncipe for all the local support during fieldwork. Additionally, we thank all the landowners that allowed us to survey on their properties.
AFP, RR, PG, ACAF, ASF, JC, JA collected the data; ACAF and ASF processed the acoustic data under the supervision of NY; JM-A and FA-M curated the data; AFP led the writing and all the co-authors contributed with comments and revisions to drafts of the manuscript.