DOI: 10.5061/dryad.fn2z34v4s
title: Environmental and habitat data of Great Slaty Woodpecker in Western Nepal

description: The Great Slaty Woodpecker (Mulleripicus pulverulentus) has experienced a
 rapid population decline due to the loss of primary forest habitats across
 its range. Despite being classified as globally Vulnerable, detailed
 information regarding its status and distribution is largely insufficient
 and outdated. To address this, we conducted surveys from 2019 to 2021 in
 the western Terai Arc Landscape of Nepal, covering 29 transects, each 5
 kilometers long, to estimate the present population status, nature of
 excavated cavities, and overall distribution of the species in Nepal. We
 measured the diameter at breast height (DBH) within 15 meter circular
 plots at each woodpecker sighting location to explore the relationship
 between tree diameter and woodpecker presence. Additionally, we modeled
 the potential distribution of the Great Slaty Woodpecker across Nepal
 using available occurrence points. A total of 81 individuals were recorded
 across 14 transects, with 66 individuals within protected areas and 15
 outside. Our finding demonstrated a direct correlation between tree DBH
 and woodpecker presence, indicating that large trees are critical for the
 species, with an average DBH of 61.26 cm for trees where woodpeckers
 excavated cavities. Furthermore, we found that the total suitable habitat
 for the species in Nepal is approximately 6,738 km², with a significant
 portion located outside protected areas. The habitat in community forests,
 outside protected areas is particularly vulnerable to selective logging,
 posing a threat to the species. Therefore, further studies on the impact
 of logging on the Great Slaty Woodpecker are essential for effective
 conservation strategies.
description: <strong>Data Collection</strong>
 Potential habitats for <em>M. pulverulentus</em> were
 identified through using a combination of literature reviews, expert
 recommendations, and consultations with local birding groups.Field data
 were collected through transect surveys, each 5 km length, across five
 blocks in protected and outside the protected areas.
 Surveys were conducted during the breeding season, spanning from
 March-July, in the years 2019 and 2021. No surveys were conducted in 2020
 due to COVID-19 restrictions. Surveys were conducted from 0700 hrs to 1200
 hrs in the morning and 1500 hrs to 1700 hrs in the evening, with surveyors
 walking at a pace of 1 km/hr. We recorded observations of <em>M.
 pulverulentus</em> individuals sighted or heard during these
 surveys, defined as “per sighting”. termed per sighting later. Additional
 observations made outside the designated transects and opportunistic
 sightings after 2021 were noted and utilized as presence points for
 distribution modeling and to better understand species’ overall
 distribution. We compiled 156 occurrence points of M.
 pulverulentus collected between March 2017 and May 2024. These data points
 were sourced from our field surveys, opportunistic sightings, and
 published records accessed through the Global Biodiversity Information
 Facility (GBIF). <strong>Habitat
 Data</strong> At each detection point, a circular
 plot of 15 m was established to measure the Diameter at Breast Height
 (DBH) of trees, along with tree height and forest type. Furthermore, when
 the excavated cavities were identified the DBH of the excavated tree was
 measured, the number of excavated cavities were counted. The cavity height
 from the ground was also measured.
 <strong>Habitat Distribution</strong>
 We used MaxEnt (version 3.4.1) with bioclimatic variables and
 occurrence data to model predicted habitat distributions for <em>M.
 pulverulentus</em> in Nepal. All variables were included after
 confirming acceptable multicollinearity levels (|r| &lt; 0.70)
 (Dormann et al., 2013). Presence points were spaced at least 1 km apart to
 minimize spatial autocorrelation. Model settings included 1,000 maximum
 iterations and 10 replicates. Model performance was evaluated using
 threshold-independent and threshold-dependent methods.  AUC values below
 0.7 indicate poor performance, 0.7–0.9 suggest moderate performance, and
 values above 0.9 denote excellent performance (Pearce and Ferrier, 2000).
 True Skill Statistics (TSS), calculated as Sensitivity + Specificity - 1,
 assessed threshold-dependent performance, with values ranging from -1 to 1
 (Allouche et al., 2006). We averaged TSS scores from all 10 model runs
 using R software (R Core Team, 2018). Additionally, the habitat map was
 clipped by land use change to identify the current habitat status across
 various land use forms in Nepal.
description: # **Environmental variables and habitat data of the Great Slaty Woodpecker
 in Western Nepal** ## Access this dataset on Dryad DOI:
 [https://doi.org/10.5061/dryad.fn2z34v4s](https://doi.org/10.5061/dryad.fn2z34v4s) ## Description of the data This dataset supports ecological research on the Great Slaty Woodpecker (*Mulleripicus pulverulentus*), a globally vulnerable species, and its habitat in the Terai Arc Landscape of Nepal. Field surveys were conducted during the 2019 and 2021 breeding seasons, with supplementary opportunistic sightings and GBIF records from 2019–2024. Data includes presence points of the species, tree and cavity measurements, and environmental variables for modelling the habitat distribution of the species. The dataset facilitates the species distribution modelling of the species and to understand the habitat suitability analysis for conservation purposes.  ### Files and variables #### File: GSWData.zip **Description:**  ### Description of the data and file structure #### 1. cavitytrees (.csv file) This data sheet contains information about the trees that were ecavated by Great Slaty Woodpecker. Columns: Tree Number: The tree number used to identify the cavity trees Latitude, Longitude: Location Coordinates (degrees decimal) Site Name: Area of study where the cavity tree was seen Altitude: Elevation (meters) Tree Species: Name of the species of cavity tree DBH: Diameter at Breast Height of cavity tree (centimetres) Height of the tree: Height of the cavity tree (meters) Number of cavities: Number of cavities seen in the tree Height of cavity above the ground: Height of the cavity above the ground, height of the first cavity from the ground if there were multiple cavities (meters) Status of cavity tree: If the tree was alive or dead. #### 2. DBHdata (.csv file) This data contains information about the DBH of the trees in the plot where the species was present. Columns: S.No.: Serial Number District: Area name where the data was collected Tree species: Local Nepali names of the trees inside the plot Scientific name: Scientific names of the trees DBH: Diameter at breast height of the trees (Centimetres) Height: Height of the trees (meters) #### 3. Presencepoints (.csv file) This data file contains the location data obtained during the field survey. Columns: S. No.: Serial Number Area: Area name where the species was sighted Species: Scientific name of Great Slaty Woodpecker Latitude, Longitude: Location Coordinates (degrees decimal) #### 4. Transectdata: This data contains all the information about the transect and the number of individuals counted in the transect. Columns: S. No.: Serial Number Area: Study area where the transects were laid Transect ID: Transect identification number Start Point: Starting point of the transect (degrees decimal) End Point: Ending point of the transect (degrees decimal) Presence points: Number of locations where the species was observed in each transect. NA means no record of the species in the transect. Individual counted: Number of individuals counted in each transect. Human Activities: Type of human disturbance in the transect (Low, Medium, High) Logging problem: Yes or No (If the area has faced any logging in the recent time) PA/OutPA: If the transect lies in a designated protected area (PA) or outside the protected areas (out PA) ## Geographic Coordinate Generalisation The geographic coordinates in this dataset have been generalized to reduce precision to protect the threatened species (*Mulleripicus pulverulentus*) from potential risks such as poaching and habitat disturbance. The precision of the coordinates has been reduced to two decimal places. This adjustment follows the guidelines provided by GBIF on sharing sensitive species data. ## Abbrevations DBH: diameter at breast height NA: Not Applicable (cells containing NA) GBIF: Global Biodiversity Information Facility. ## Access information The dataset is publicly available through the Dryad Digital Repository. **Data were derived from the following sources:** Field surveys: Conducted in protected and outside-protected areas of Nepal between 2019–2021 For any questions, please reach out to: * **Name**: Deelip Chand Thakuri * **Email**: [deelip.chand.thakuri@gmail.com](mailto:deelip.chand.thakuri@gmail.com)