This DAVIES_2021__DATA_README.txt file was generated on 2022-04-06 by Andrew Davies


GENERAL INFORMATION

1. Title of Dataset: Data from: Environmental controls on African herbivore responses to landscapes of fear.

2. Corresponding Author
		Name: Dr Andrew Davies
		Institution: Harvard University, Cambridge, MA, USA
		Email: andrew_davies@g.harvard.edu

3. Date of data collection: September 2014

4. Geographic location of data collection: Hluhluwe-iMfolozi Park (HiP), South Africa

5. Funding sources that supported the collection of the data: Earthwatch Institute

6. Recommended citation for this dataset: Davies, Andrew et al. (2021), Data from: Environmental controls on African herbivore responses to landscapes of fear, Dryad, Dataset


DATA & FILE OVERVIEW

1. Description of dataset

These data were generated to investigate large mammalian herbivore population sizes and spatial distributions across HiP.

2. File List: 
	File 1 Name: grey.duiker.csv
	File 1 Description: Census observations of grey duiker

	File 2 Name: red.duiker.csv
	File 2 Description: Census observations of red duiker

	File 3 Name:  white.rhino.csv
	File 3 Description: Census observations of white rhino

	File 4 Name: buffalo.csv
	File 4 Description: Census observations of buffalo

	File 5 Name: zebra.csv
	File 5 Description: Census observations of plains zebra

	File 6 Name: wildebeest.csv
	File 6: Description: Census observations of blue wildebeest

	File 7 Name: warthog.csv
	File 7 Description: Census observations of warthog

	File 8 Name: giraffe.csv
	File 8 Description: Census observations of southern giraffe

	File 9 Name: kudu.csv
	File 9 Description: Census observations of greater kudu

	File 10 Name: impala.csv
	File 10 Description: Census observations of impala

	File 11 Name: nyala.csv
	File 11 Description: Census observations of Ayala
	

METHODOLOGICAL INFORMATION

From 12 July to 18 September 2014, which is the late dry season in HiP, groups of two trained observers (one field ranger paired with a volunteer) walked 30 line transects ranging in length from 2 to 11 km, for a total of 232 km, and recorded the locations and group sizes of all herbivores encountered with the use of binoculars, a GPS unit, compass and Bushnell Yardage Pro 1000 range finder. The field ranger was largely responsible for the observations, while the volunteer recorded them into the database. This census is performed biennially in HiP and is highly standardized across years and between transects, making consistent observer bias highly unlikely. The bearing of, and distance to, each sighting (using herd centres when groups were encountered) were recorded to calculate the location of each observation relative to the transect line. In cases where animals moved after they had been sighted, observations were recorded where the animal (or herd) was first seen. If an animal (or herd) was not initially observed, but rather disturbed by the observers and then seen running off, it was not recorded. Effects of detectability and distance on group counts were accounted for using Distance software. Each transect was walked between five and thirteen times over the course of the survey, yielding a total survey distance of 2715 km. To avoid potential detection bias across different habitat types and vegetation densities, the datasets only include the observations recorded within 100 m of the observer (number of observations per species: red duiker = 52, grey duiker = 105, impala = 266, nyala = 287, kudu = 41, giraffe = 59, warthog = 101, wildebeest = 37, zebra = 82, buffalo = 145 and white rhinoceros = 326). Transects were evenly distributed throughout the park, apart from the access-limited, south-western wilderness area that excluded from the study due to no available lion spatial data, encompassing all main vegetation types and variability in rainfall and elevation. An equal number of random points, matching the maximum number of observations for any one herbivore species (i.e. 326), were generated within 100 m buffers around the surveyed transects to represent available habitat.

DATA-SPECIFIC INFORMATION FOR EACH DATASET:

1. Number of variables: 13

2. Number of cases/rows: 75 - 653

3. Variable List: 
	FID: Unique identifier for each record (row)
	Date: Date (m/d/yyyy) of observation
	Species: herbivore species observed
	presence: whether an herbivore was observed (1) or not (0). If not, the row represents a random point
	Total: number of herbivores f that species observed
	UTMe: UTM east position of the observation 
	UTMn: UTM north position of the observation 
	Landsat: Ladsat image corresponding to that observation (1 or 2)
	graze/browse: quantity of graze or browse available at that observation or random point (calculated form remotely-sensed data)
	lion.risk: lion encounter risk at the observation or random point
	wd.risk: wild dog encounter risk at the observation or random point
	viewshed.area: visible area calculated from LiDAR data fro that observation or random point
	X... : proportion of area (within a 50 m circle) at that observation or random point for the height specified by the number following the X

4. Missing data codes: 
	None

5. Abbreviations used: 
	N/A; not applicable