DOI: 10.5061/dryad.7wm37pw1p
title: Data from: Are crop fields pharmacies for megaherbivores? From ecophysiological studies of elephant (<em>Loxodonta cycotis</em>) crop raiders in Gabon

description: Damage to crops is a major cause of human-elephant conflict (HEC) in
 elephant range states. Elephant crop raiding drives farmers'
 resentment against elephants and reduces local community support for
 wildlife conservation. While elephant crop raiding ecology is well
 studied, further investigations on HEC mitigation strategies are still
 needed. Thus, there is a need to focus on less investigated areas, such as
 the physiological drivers of elephant crop-raiding behavior, using
 multidisciplinary sciences. Two physiological proxies, gastrointestinal
 parasite infestations (GPI) and fecal glucocorticoid metabolite (fGCM)
 concentrations, common in animal ecophysiology, were used to help
 understand differences or motivations in the preferences of crops by
 elephant raiders. The results show, for the first time, that forest
 elephants may increase the frequency of crop raiding according to GPI,
 indicating a self-medication behavior. Increases in parasitism prevalence
 (PP) and parasitism intensity (PI) in sampled boluses led to 28% and 0.16%
 more intakes of all crops, respectively. Parasitism prevalence (PP)
 increases in elephant boluses also led to 16% and 25% more bananas and
 papaya intakes, respectively, while PI increases in boluses led to 0.1%
 more intakes of both bananas and papaya plants. No such predictions were
 found for other crops (cassava and palm plant), nor for natural food
 species. Furthermore, fGCM concentrations were not related to elephant
 crop raiding. Results highlight a trade-off between the benefit of
 elephants raiding crops and the danger of encountering farmers by adopting
 nocturnal crop-raiding behaviours.
description: # Data from: Are crop fields pharmacies for megaherbivores? From
 ecophysiological studies of elephant (*Loxodonta cycotis*) crop raiders in
 Gabon Dataset DOI: [10.5061/dryad.7wm37pw1p](10.5061/dryad.7wm37pw1p) ##
 Description of the data and file structure Forest elephant crop raiding
 according to FGCM and GIP ### Dataset Overview This data includes
 frequencies of forest elephant crop raiding events as well as fecal
 glucocorticoid metabolite concentrations and gastrointestinal parasitism
 presence. The data is composed by 90 rows corresponding to individual
 elephants sampled. Columns represents variables with Fecal Glucocorticoid
 concentration, parasite prevalence (PP), and parasitism intensity (PI)
 being the response variables and the others being the explanatory
 variables. ### Funding These data were collected through a research work
 funded by COLAS-Gabon with the collaboration of IRAF-CENAREST (Gabon),
 Nature+ asbl NGO (Belgium), and Gembloux ABT, University of Liège
 (Belgium). COLAS-Gabon, IRAF-CENAREST, and Nature+ provided logistic and
 financial support for the field work to SN. Gembloux Agro-Bio Tech,
 University of Liège (Belgium), and RESSAC (CIFOR-ICRAF) provided financial
 support for data analyses, manuscript writing, and publishing. ### Ethics
 Approval The National Center for Scientific Research and Technology
 (Centre National de la Recherche Scientifique et Technologique, CENAREST)
 and the National Agency of National Parks (Agence National des Parcs
 Nationaux ANPN) in Gabon provided permissions to conduct this research.
 ### Files and variables #### File:
 Forest_elephant_crop_raiding_according_to_FGCM_and_GIP.csv
 **Description:** fecal glucocorticoid metabolite concentrations (fGCM), as
 well as parasite prevalence (PP) and parasite intensity (PI), are the
 response variables. The others parameters are explanatory variables. #####
 Variables * Seasons: Our observational experimental blocks were seasons
 with five modalities (S1=Long dry season; S2 = short wet season; S3 =
 short dry season; S4 = long wet season; S5= second long dry season) *
 S5: second long dry season * S4: long wet season * S3:short dry season *
 S2:short wet season * S1: Long dry season * Elephant.Groups: * Crop:
 represents the presence (1) and absence (0) of farmed plants eaten by
 elephants. * Crops: represent all farmed plants eaten by elephants. *
 Food.sp: represents all plant species eaten by elephants * Nat.food: is a
 numerical form of non-croped plants eaten by elephantsNat.food.: is the
 numerical form of non-croped plants eaten by elephants *
 Natural.food: represents all non-crop plants eaten by elephants * Banana:
 is a crop species eaten by elephants * Banana.: is the numerical form of
 the banana crop species eaten by elephants * Cassava: is a crop species
 eaten by elephants * Cassava.: is the numerical form of the cassava crop
 species eaten by elephants * Papaya: is a crop species eaten by elephants
 * Papaya.: is the numerical form of the papaya crop species eaten by
 elephants * Palm: is a crop species eaten by elephants * Palm.: is the
 numerical form of the palm crop species eaten by elephants * Costus: is a
 natural species eaten by elephants * Cost.: is a natural species eaten by
 elephants (numeric) * Bamboo: is a natural species eaten by elephants *
 Bamboo.: is a natural species eaten by elephants (numeric) * Fern: is a
 natural species eaten by elephants * Fern.: is a natural species eaten by
 elephants (numeric) * Ficus: is a natural species eaten by elephants *
 Ficus.: is a natural species eaten by elephants (numeric) * Parasitism:
 indicates the presence (1) or absence (0) of parasite eggs in elephant
 dung * PP: is parasitism prevalence * FGM.conc: fecal glucocorticoid
 metabolite concentrations * FGMcx10: fecal glucocorticoid metabolite
 concentrations times 10 for graphical depictions * FGM.conc/SEM: fecal
 glucocorticoid metabolite concentrations for graphical depiction *
 EPGD.c: egg per gram of boluses * PI:Parasitism intensity * EPGDx100: egg
 per gram of boluses times 100 (for graphical representations) *
 EPG.cat: egg per gram of boluses (categorised)  * OPG.cat.num: egg per
 gram of boluses (numeric) * PP.ord: Parasitism prevalence (ordinal for
 analyses) * OPG.cat.L.H.num: egg per gram of boluses (categorised for
 analyses) ## Code/software We performed descriptive and inferential
 statistical calculations using Excel software and R version 4.0.4 (R
 Development Core Team 2025). We performed descriptive statistics,
 including percentage calculations, charts’ design, and principal component
 analyses (PCA) showing correlations between variables. In inferential
 statistics, the *Shapiro* test was used to assess the normality of
 response variables, while the *X^2^* dependency test was used to assess
 whether variables were dependent. As most of our data were counts, we used
 nonparametric ANOVA tests (Kruskal and Wilcoxon) to calculate PP, PI, and
 fGCM differences according to plant intakes. We also used the *lme4*
 package to perform generalized linear mixed models (GLMMs) analyses to
 predict the effects of PP, PI, and fGCM on elephant plant species intakes
 over time.