FBIP: The effect of land-use on the butterfly diversity of ecological refugia within an agricultural landscape

Falko Buschke1, Mahlatse Kgatla2

1 University of the Free State, Room 10.103, Agricultural Building, University of the Free State, 9300, Bloemfontein, South Africa; 2 SANBI, 2 Cussonia Avenue, 0184, Pretoria, South Africa

Corresponding author(s): Falko Buschke (falko.buschke@gmail.com)

Received {date}; Revised {date}; Accepted {date}; Published {date}

Citation: Combination of authors, year of data paper publication (in parentheses), Title, Journal Name, Volume, Issue number (in parentheses), and doi of the data paper.

Resource Citation

Buschke F (2020): FBIP: The effect of land-use on the butterfly diversity of ecological refugia within an agricultural landscape. v1.1. South African National Biodiversity Institute. Dataset/Occurrence. http://ipt.sanbi.org.za/iptsanbi/resource?r=effect&v=1.1

Abstract

This study proposes to survey the butterfly diversity of the eastern Free State inselberg mountain refugia.

Keywords: Occurrence, Observation

Project details

Project title: The effect of land-use on the butterfly diversity of ecological refugia within an agricultural landscape
Personnel: Falko Buschke
Funding: Foundational Biodiversity Information Programme
Study area descriptions/descriptor: Free State (Eastern Free State)

Data published through GBIF: http://ipt.sanbi.org.za/iptsanbi/resource?r=effect

Taxonomic coverage

General taxonomic coverage description: Butterflies
Taxonomic ranks
Order: Lepidoptera
Common names: Butterfly

Spatial coverage

General spatial coverage: Free State (Eastern Free State)
Coordinates: 30°39'25.2''S and 26°43'33.6''S Latitude; 24°23'24''E and 29°45'3.6''E Longitude 

Temporal coverage: February 8, 2017 - March 1, 2018

Methods

Method step description: This study requires five work-packages:
1. A GIS-based desktop study and survey design,
2. A field feasibility and pilot survey,
3. Aseasonal survey of the butterfly assemblage,
4. The management of data and estimation of population abundances and
5. The publication of field data.
Work-package 1 is already in progress and will be completed before the FBIP grants are awarded. It is described here to provide context for the rest of the study. Similarly, Work-package 5 will only occur after the end of the FBIP grant-cycle because time-lines are variable during the scientific peer-review process. Nevertheless,
the data from this study will be publicly accessible at the end of Work-package 4 by 15 December 2017. Below is an outline for each of the five work-packages.
Work-package 1 - GIS desktop study and survey design
Timeline: Currently ongoing - 03 October 2016
Purpose: To establish a scientifically-robust and representative survey design for inselbergs in the agricultural landscape of the eastern Free State.
Activities: Characterising the inselbergs of the eastern Free State based on key biophysical characteristics (e.g. elevation, area, isolation, slope, habitat type) using a 30
m digital elevation model as well as national and provincial land-cover data.
Selecting a representative subset of inselbergs from a 40,000 hectare portion to the south-west of Bethlehem. The aim is to establish 50 independent survey transects
(300 - 700 m depending on habitat uniformity). Of these, 20 transects will be from 10 different inselbergs varying in their biophysical characteristics (2 transects per
inselberg) and 20 transects will be in a 2km buffer around each inselberg (2 transects per inselberg). Ten random transects will be in the surrounding matrix. Where
possible, the selection of transects will be done using randomised sampling tools in a GIS (e.g. Research Tools plugin for QGIS).
Deliverables: A map with inselbergs, land-cover and geographic location of sampling transects. A report on the biophysical characteristics of each inselberg and the
habitat characteristics of each transect

Work-package 2 - Field feasibility and pilot survey
Timeline: (3 weeks) 21 November - 09 December 2016
Purpose: Validate the accessibility of survey transects and compile a species reference data set.
Activities: A field survey to ground-truth the selected sampling transects to confirm access to properties of local landowners and confirm physical accessibility to each transect.
Each transect will be characterised in terms of length, habitat type and average vegetation height.
During this visit, a photo database will be set up for as many butterflies species as possible to set up a reference dataset for subsequent surveys refine the sampling protocol.
Deliverable: An updated map of survey transects that incorporates land-owner permission and accessibility. A photo database of butterfly species.

Work-package 3 - Seasonal survey of the butterfly assemblage
Timeline: (cumulative 8 weeks) 06 - 17 February 2017; 02 - 12 May 2017; 07 - 18 August 2017; 06 - 17 November 2017.
Purpose: To gather a site-by-species matrix of butterflies observed in each transect.
Activities: Sample butterflies at each transect using the standardised 'Pollard Walk method' [1]. This entails walking the transect between 10:00 and 15:00 and recording all the butterflies observed in a three-dimensional forward-facing 5m box. The species identity will be recorded for each specimen as will be the linear distance from the centre transect line to the nearest 10 cm to quantify species-specific detection curves used to calculate the butterfly abundance [2]. This will be repeated for each survey transect during four seasons: February, May, August and November.
Accompanying the main observer is a second observer tasked with capturing any observed, but unidentified, specimens with a butterfly net to add to the photo-database.
The second observer will not make observations themselves (to avoid observer bias), but will only support the main observer.
Deliverables: Four site-by-species matrices that include records for each observed specimen.

Work-package 4 - Management of data and estimation of population abundances
Timeline: (3 weeks) 20 November - 08 December 2017
Purpose: To determine butterfly abundances and habitat affinities
Activities: Calculating the abundances of butterflies in each transect after correcting for species-specific detectability [2]. Once these abundances are calculated, it is possible to determine habitat affinities for each species.
Deliverables: A dataset with abundances and habitat affinities for each species. Also, a summary report on how the butterfly assemblage varies with inselberg characteristics and surrounding land-use.
Study extent description: Free State (Eastern Free State)
Sampling description: At each inselberg, butterflies were sampled at each transect using a modified 'Pollard Walk method' [1]. This entailed walking the transect between 10:00 and 15:00 and recording all the butterflies observed along the transect, as well as estimating the distance of the specimen from the observer. The species identity was recorded for each specimen as was the linear distance from the centre transect line to the nearest 50 cm to quantify species-specific detection curves used to calculate the butterfly abundance [2]. This was be repeated for each survey transect, to cover the north- and south facing slopes as well as matrix surrounding each inselberg. 

References
1 - Pollard & Yates (1993) Monitoring butterflies for ecology and conservation. Chapman and Hall, London.
2 - Isaac et al. (2011) Distance sampling and the challenge of monitoring butterfly populations. Methods Ecol. Evol., 2, 285-594.

Datasets

Dataset description
Object name: Darwin Core Archive FBIP: The effect of land-use on the butterfly diversity of ecological refugia within an agricultural landscape
Character encoding: UTF-8
Format name: Darwin Core Archive format
Format version: 1.0
Distribution: http://ipt.sanbi.org.za/iptsanbi/archive.do?r=effect
Publication date of data: 2020-07-01
Language: English
Licences of use: Creative Commons Attribution (CC-BY) 4.0 License

Metadata language: English
Date of metadata creation: 2020-06-29
Hierarchy level: Dataset