Line transect surveys of chimpanzees (Pan troglodytes verus) and other medium/large mammals in Boe, Guinea-Bissau, 2014

Data as a DwC-A file	download 3,915 records in English (151 KB) - Update frequency: not planned
Metadata as an EML file	download in English (10 KB)
Metadata as an RTF file	download in English (10 KB)

Description

This dataset presents line-transect survey data collected in the Boe sector, Gabu Region, southeastern Guinea-Bissau, in 2014, as part of field monitoring following the Pan African Programme's standardized survey protocol for great apes and associated fauna. Fourteen fixed ~3,750 m transects (L1N/S through L7N/S) were each walked one to three times during 2014. Observers recorded every direct sighting and indirect sign (nests, dung, footprints, vocalisations, feeding remains, tool-use evidence) of western chimpanzees (Pan troglodytes verus) and other medium/large mammals encountered along each transect, together with the perpendicular distance to each detection, GPS location, and habitat type. Each transect walk (transect x round) is a parent Event; each recorded waypoint along that walk is a child Event. Species detections are linked via the Occurrence extension. Because each transect walk has an explicit, reported taxonomic scope (medium/large Mammalia, chiefly P. t. verus), non-detection of a species that was recorded elsewhere in the Boe dataset during that walk is published as an explicit dwc:occurrenceStatus = absent record, following GBIF's Humboldt Extension for Ecological Inventories guidance. Quantitative measurements (perpendicular distance, tool dimensions, transect length) are published via the Extended MeasurementOrFact extension. NOTE ON ABSENCE INFERENCE: the target species pool used to infer absence is restricted to the 34 species/taxa actually detected somewhere in the Boe line-transect dataset during 2014-2015.

Data Records

The data in this sampling event resource has been published as a Darwin Core Archive (DwC-A), which is a standardized format for sharing biodiversity data as a set of one or more data tables. The core data table contains 3,915 records.

2 extension data tables also exist. An extension record supplies extra information about a core record. The number of records in each extension data table is illustrated below.

3915

2088

118

This IPT archives the data and thus serves as the data repository. The data and resource metadata are available for download in the downloads section. The versions table lists other versions of the resource that have been made publicly available and allows tracking changes made to the resource over time.

Versions

The table below shows only published versions of the resource that are publicly accessible.

How to cite

Researchers should cite this work as follows:

van Schijndel J, Goedmakers A (2026). Line transect surveys of chimpanzees (Pan troglodytes verus) and other medium/large mammals in Boe, Guinea-Bissau, 2014. Version 1.0. Chimbo. Samplingevent dataset. https://ipt.nlbif.nl/resource?r=boe_guinee-bissau_line-transects&v=1.0

Rights

Researchers should respect the following rights statement:

The publisher and rights holder of this work is Chimbo. This work is licensed under a Creative Commons Attribution (CC-BY 4.0) License.

GBIF Registration

This resource has not been registered with GBIF

Keywords

chimpanzee; Pan troglodytes verus; line transect; distance sampling; Guinea-Bissau; Boe; Samplingevent; Samplingevent; Observation

Contacts

Joost van Schijndel

Originator

Chimbo Foundation

Annemarie Goedmakers

Point Of Contact

Chimbo Foundation

Annemarie Goedmakers

Point Of Contact

Chimbo Foundation

Huningspaed 6

8567 LL Oudemirdum

+31-6-17280797
+245-955.521.674
+245-966.726.916

https://www.chimbo.org/

Geographic Coverage

Boe sector, Gabu Region, southeastern Guinea-Bissau (Boe National Park and surrounding forest-savannah mosaic)

Bounding Coordinates	South West [11.7, -14.3], North East [12.1, -13.6]

Taxonomic Coverage

Medium and large Mammalia, with a primary focus on Pan troglodytes verus (western chimpanzee); incidental records of other vertebrates and human activity signs.

Class	Mammalia
Species	Pan troglodytes verus (Western Chimpanzee)

Temporal Coverage

Start Date / End Date	2014-01-01 / 2014-12-31

Project Data

No Description available

Title	Structured distance-sampling survey, per-observation rows, UTM coords, effort recorded (start/end waypoints, weather)

The personnel involved in the project:

Joost van Schijndel

Principal Investigator

Sampling Methods

Standardised line-transect distance sampling; see dwc:samplingProtocol and the Humboldt extension eco:protocolDescriptions field in event.txt for per-event detail.

Study Extent	Boe sector line-transect network, 2014 field season.

Method step description:

Fourteen fixed transects (L1N, L1S ... L7N, L7S), each approximately 3,750 m long, were pre-cut through the Boe survey area to sample the range of habitats present (forest, forest-on-rock, gallery forest, savannah, fallow, marshes). Each transect was walked slowly by a team including at least one trained observer and local field assistants. All direct sightings and indirect signs of chimpanzees and other medium/large mammals within visual range of the line were recorded, together with GPS waypoint, perpendicular distance from the line, habitat at the point of detection, and (for chimpanzee nests) decay stage. Each transect was walked one to three times during 2014 (rounds 1-3). Weather conditions, start/end times, and the field team were logged for each walk.

Additional Metadata

Maintenance Description	TODO: e.g. "completed" or "ongoing" depending on whether more Boe survey years will be added.
Alternative Identifiers	https://ipt.nlbif.nl/resource?r=boe_guinee-bissau_line-transects