DOI: 10.5061/dryad.v41ns1s63
title: Data from: Changes in vertical stratification of neotropical nymphalid butterflies at forest edges are not directly caused by light and temperature conditions

description: Habitat fragmentation and land use changes threaten neotropical habitats
 and alter patterns of diversity at forest edges. Like other arthropod
 assemblages, neotropical fruit-feeding butterfly communities show strong
 vertical stratification within forests, with some recent work showing its
 potential role in speciation. At forest edges, species considered to be
 forest canopy specialists have been observed descending to the forest
 understory, with the similarity in light conditions between the canopy and
 understory strata at edges hypothesized to be responsible for this
 phenomenon. We conducted a study using standardized sampling to document
 and quantify this edge effect, characterize edge and forest strata, and
 estimate the relative contributions of temperature and light conditions to
 changes in nymphalid butterfly stratification at forest edges. We found
 strong evidence of an edge effect in these butterflies and confirmed
 strong differences in light and temperature, showing that the edge
 understory differs little from forest canopy conditions. Of 41 species
 common to both forests and edges, 28 shifted to have a lower canopy
 probability at the edge, and our model detected a decrease in canopy
 probability of 0.165. Furthermore, our analysis indicated the relative
 abundance of canopy taxa increased at the edge, and the tribes Haeterini
 and Morphini were especially sensitive to edge effects. However, the
 analyses here did not clearly implicate temperature or light magnitude in
 causing changes in neotropical nymphalid vertical stratification at forest
 edges. Instead, our results point to other mediator variables as being
 important for changes at tropical forest edges. From our data,
 edge-responsive species can be separated into two different categories,
 which likely relates to their resilience to anthropogenic disturbance. We
 also note that structural causal models have a potential place in future
 work on tropical conservation, given they can provide causal estimates
 with observational data.
description: Paired, baited understory and canopy butterfly traps were placed
 at edge, ridge, and valley locations (a total of 32 trap pairs) at La
 Selva Biological Station May 2015 - August 2016. From 26 May 2015 to 12
 August 2015, traps were checked four consecutive days a week; from 12
 September 2015 to 10 August 2016, traps were checked five consecutive days
 in the second week of each month. Bait was added to the traps on the first
 day of each sampling week and supplemented as needed to maintain potency.
 Butterflies were photographed and marked, and HOBO loggers recording
 temperature and light data were attached to traps.
description: # Data from: Changes in vertical stratification of neotropical nymphalid
 butterflies at forest edges are not directly caused by light and
 temperature conditions
 [https://doi.org/10.5061/dryad.v41ns1s63](https://doi.org/10.5061/dryad.v41ns1s63) ## Description of the data and file structure This dataset contains butterfly trap records and temperature and light logger data from La Selva Biological Station, Costa Rica, May 2015 - August 2016. ### Files and variables #### File: our\_captures.csv **Description:** This file contains butterfly observations from canopy and understory traps. ##### Variables * Date: when captured individual was recorded, M/D/YYYY * Gen_sp: initial genus and specific epithet joined by a period * Lamas_name: genus and specific epithet joined by a period, standardized to *Checklist: Part 4A. Hesperioidea - Papilionoidea*, Lamas et al. (2004). * subfamily: individuals' subfamily * tribe: individuals' tribe * Trap: Trap ID number * Stratum: c or u for canopy and understory respectively * bait: bait type for the butterfly observation #### File: LaSelva\_AllData\_HOBO\_concat\_TRIMMEDFeb2020\_new\.csv **Description:** This file contains the temperature and light HOBO logger data series for the traps. ##### Variables * Logger_filename: HOBO logger source filename * Trap: Trap ID number * Stratum: c or u for canopy and understory respectively * Read: HOBO logger observation sample number * Date: Date of measurement, M/D/YYYY * Time: hour of day * Temp_C: Temperature in Celsius * Light_Lux: Light in lux ## Code/software Files can be opened with Microsoft Excel, R, or any other software suitable for csv files.