DOI: 10.5061/dryad.ms65f29
title: The distribution of plant consumption traits across habitat types and the patterns of fruit availability suggest a mechanism of coexistence of two sympatric frugivorous mammals

description: Understanding the mechanisms governing the coexistence of organisms is an
 important question in ecology, and providing potential solutions
 contributes to conservation science. In this study, we evaluated the
 contribution of several mechanisms to the coexistence of two sympatric
 frugivores, using western lowland gorillas (Gorilla gorilla gorilla) and
 central chimpanzees (Pan troglodytes troglodytes) in a tropical rainforest
 of southeast Cameroon as a model system. We collected great ape fecal
 samples to determine and classify fruit species consumed; we conducted
 great ape nest surveys to evaluate seasonal patterns of habitat use; and
 we collected botanical data to investigate the distribution of plant
 species across habitat types in relation to their “consumption traits”
 (which indicate whether plants are preferred or fallback for either
 gorilla, chimpanzee, or both). We found that patterns of habitat use
 varied seasonally for both gorillas and chimpanzees and that gorilla and
 chimpanzee preferred and fallback fruits differed. Also, the distribution
 of plant consumption traits was influenced by habitat type and matched
 accordingly with the patterns of habitat use by gorillas and chimpanzees.
 We show that neither habitat selection nor fruit preference alone can
 explain the coexistence of gorillas and chimpanzees, but that considering
 together the distribution of plant consumption traits of fruiting woody
 plants across habitats as well as the pattern of fruit availability may
 contribute to explaining coexistence. This supports the assumptions of
 niche theory with dominant and subordinate species in heterogeneous
 landscapes, whereby a species may prefer nesting in habitats where it is
 less subject to competitive exclusion and where food availability is
 higher. To our knowledge, our study is the first to investigate the
 contribution of plant consumption traits, seasonality, and habitat
 heterogeneity to enabling the coexistence of two sympatric frugivores.
description: 1) Botanical
 data Data collected on woody
 plant species found in faecal samples of gorillas and chimpanzees in 184
 plots of 25 x 25 m in 2014. Data
 description 1-a) Plot ID: The unique
 code for each plot 1-b) Longitude: the
 longitude component of the geographical coordinates of the plots, in UTM
 33 N 1-c) Latitude: the
 latitude component of the geographical coordinates of the plots, in UTM 33
 N 1-d) Habitat type:
 vegetation characteristics of each plot. Values: Old secondary forest,
 Near primary forest, Young secondary forest, Swamp, Riparian
 forest 1-e) Plant ID: the
 unique identification of each individual plant 1-f) Plant form: Tree,
 liana, strangler (Ficus spp) 1-g) Species traits: the
 plant consumption traits indicating whether the species is preferred or
 fallback (see the main article, Table 2). Values: Preferred gorilla
 (preferred by gorillas only), Preferred chimpanzee (preferred by
 chimpanzee only), Preferred apes (preferred by both gorillas and
 chimpanzees), Fallback gorilla (fallback for gorillas only), Fallback apes
 (fallback for both gorillas and chimpanzees), UC (unclassified), NA (no
 species was found in the plot) 1-h) Scientific names
 genus level: the scientific names of the species, determined at the genus
 level in faecal samples for genus with several species consumed by great
 apes 1-i) Scientific names
 species level: the scientific names of species, determined at the species
 level, excepted for unidentified species 1-j) Family: the family
 names of species 1-k) DBH: the diameter
 at breast height of the individual plant (in centimetre)
 Botanical inventories
 25x25m _for great apes coexistence2.csv 2) Mean weight of fruits
 and mean number of seeds for each species 2-a) Species: species
 names to the genus level, for genus with multiple species consumed by
 great apes 2-b) Family: the family
 name of the species 2-c) Mean weight per
 fruit for the species 2-d) Mean number of
 seeds per fruit for the species. NA: the seeds were
 uncountable Mean weight of fruit and mean
 number of seeds per fruit for each species2.csv 
 3) Phenological
 data 3-a) Date: the date of
 data collection 3-b) Month: the month in
 number 3-c) Season: Long dry
 season, long rainy season, short dry season, short rainy
 season 3-d) Plant ID: the
 unique identifier of each individual plant 3-e) Species: the
 scientific name of the species 3-f) Family: Family
 names 3-g) DBH: the diameter
 at breast height of the individual plant (in centimetre)
 3-h) Basal area
 (in centimetre square) 3-i) Fruit score: 0
 (none), 1 (few), 2 (many) Phenological
 data2.csv 4) Great apes nest
 survey for habitat selection Data collected by
 recording individual fresh nests from April 2009 to April 2010 on 20 – 6
 km transects located at 300 m from each other. 4-a) Nest ID: the unique
 identifier of the nest 4-b) Species: the animal
 species (Gorilla, Chimpanzee) 4-c) Scientific name:
 the scientific name of the animal species (Gorilla gorilla gorilla, Pan
 troglodytes troglodytes) 4-d) Season: the season
 when the observation was made (Long dry season, long rainy season, short
 dry season, short rainy season) 4-e) Habitat type: Old
 secondary forest, Near primary forest, Young secondary forest, Swamp,
 Riparian forest, Light gap 4-f) Month: the month of
 observation 4-g) Year: the year of
 observation Great apes nest survey for
 habitat selection analysis2.csv 5) Data from faecal
 analysis 5-a) Animal species
 (gorilla, chimpanzee) 5-b) Date of sample
 collection 5-c) Month of
 collection 5-d) Year of
 collection 5-e) Sample
 ID 5-f) Species name: The
 plant species name observed in the faecal sample 5-g) Family: The family
 name of the plant species found in the sample 5-h) Number of seeds in
 the faecal sample Great apes facal sample
 analysis January 2014 to December 2014_2.csv