DOI: 10.5061/dryad.0cfxpnw7k
title: Data from: Vertical niche usage and trait associations in Gabonese amphibians

description: Tropical forests are vertically complex, and offer unique niche
 opportunities in the form of resource, climate, and habitat-gradients from
 the forest floor to the canopy. Rainforest amphibians organize within this
 vertical space and the highest levels of vertical stratification occur in
 structurally complex and climatically stable tropical rainforests.
 Amphibians have diversified into numerous habitat and climatic niches,
 which has led to the development of a wide variety of morphological,
 behavioural, physiological, and reproductive traits. However, a lack of
 data regarding the vertical niche space used by amphibian species has
 prevented a nuanced analysis of traits and vertical height. We performed
 74 ground-to-canopy surveys for amphibians at Baposso Village, Ngounie
 Province, Gabon, and describe the vertical stratification patterns of the
 assemblage in terms of richness, abundance, and species specific vertical
 niche usage. We analyse the relationships between amphibian traits with
 vertical height using linear mixed effects models, finding strong support
 that frogs with bigger toes in relation to their length access greater
 height in the canopy. We also see differences in the vertical heights of
 species according to their reproductive modes, highlighting the importance
 of reproductive mode diversity for the vertical stratification of
 amphibian assemblages.
description: In southern Gabon, we surveyed a
 Dense Moist Forest (Verhegghen <em>et al.</em> 2012) located
 around Baposso Village, Ngounie Province, which borders the Monts Birougou
 Ramsar site (Lat 20°85′00″ N: Lon 12°13′50″; 650 – 800 m a.s.l, Figure 1).
 We focussed our sampling in older growth areas with mature trees, with
 primary canopy tree species including <em>Mutombo, Wapaka, Posso,
 </em>and<em> Paduc</em>. Temperature and humidity were
 measured at the site using climate loggers deployed in two arrays. One
 array comprised three temperature loggers (HOBO Temperature Pendant); the
 soil (10 cm below the surface), 2 m height in the understory, and 25 m
 height in the canopy. The second array utilised climate loggers (HOBO U23
 Pro v2) in the understory and canopy which record humidity in addition to
 temperature. Loggers were protected from sunlight and weather by
 installation within a PVC T-Joint pipe which allowed airflow.
 We surveyed for frogs during the wet
 season of 2022 (October – November). We conducted vertical,
 ground-to-canopy surveys for amphibians, with each survey centred on a
 single canopy tree. Tree selection was randomized; however, trees were
 required to be a minimum of 20 m apart and had to meet safety standards
 for arborist single-rope climbing (Jepson 2000). We did not limit our
 selection by tree species and were only limited in selection by safety
 concerns. We surveyed 74 trees at night for amphibians. For each tree we
 surveyed for 10 minutes at the ground, understory (2-4m), sub-canopy
 (approx. half the maximum height climbed), and canopy (maximum height
 climbed), with a 20 minute roaming survey between the strata totalling to
 60 minutes. The 10 minute ground survey consisted of searching through
 leaf litter and ground habitat in a 4 x 4 m area to standardise to the
 same search area available during climbing. Above-ground, we searched for
 arboreal amphibians in tree holes, moss, epiphytes and other microhabitat
 structures (Heyer <em>et al.</em> 1994), and measured the
 height above ground of each individual using a laser distance metre (Leica
 Geosystems, Leica Disto D2; http://www.leica-geosystems.ca).
 Encountered amphibians were
 photographed, weighed, and measured for snout-vent length (SVL), mouth
 width (hereafter: mouth), tibia length (hereafter: tibia), and toe disc
 width (3<sup>rd</sup> digit from inside thumb).
description: # Data from: Vertical niche usage and trait associations in Gabonese
 amphibians This data was collected by Edmund Basham at great cost of
 effort and resources. If downloaded for use in publications we would
 appreciate a notification on its usage and would be glad to discuss
 potential research avenues and collaborations. Please use this email for
 contact : [edmund.basham@gmail.com](mailto:edmund.basham@gmail.com) 
 **Surveys** This contains data relating to each sampling occasion,
 consisting of a vertical transect located on a tree. Tree code and Date
 (UK format throughout- DD/MM/YYYY) columns can be used to link surveys to
 individuals. Location can be determined by the longitude (decimal degrees)
 and latitude (decimal degrees), and elevation (meters above sea level)
 which are included. The start time of the survey (24hr throughout), total
 height (meters) of the tree, and the max height climbed (meters) to which
 the tree was surveyed are also included here.  **Individuals** This
 contains data relating to the individuals captured and used in this study.
 Tree code and Date columns can be used to link the survey information to
 the individuals collected on each survey. Species names are listed, along
 with the height (meters) at which the individual was found. The raw trait
 values of Mass (g), Snout to Vent Length (mm), Mouth Width (mm), Toe Disc
 Width (mm), and Tibia Length (mm) are included here. **Traits** This
 contains the scaled and averaged trait data for all species, including
 ratio traits. NA results represent traits which were unable to be sampled
 in an individual. **Climate** This contains data relating to temperature
 taken at 30 minute intervals, as well as maximum, minimum, and mean daily
 temperature (Celsius), columns 1 - 5. Secondly, represented by
 "rh" in columns 6 - 10, humidity (%) was taken at 30 minute
 intervals, as well as maximum, minimum, and mean daily results. Dewpoint
 (Celsius) is also included here in column 11.  Temperature were taken at
 separate trees (identified by the tree code column) from the soil,
 understory, and canopy, whereas humidity were only recorded at the
 understory and canopy. These are denoted by the "Strata" column.
 Data can be linked to the survey tab by tree code which contains their
 longitude and latitude coordinates. NA results represent summary columns
 which are only populated at the times where averages or maximum/minimum
 values are inputted. All values have a recorded time and date. Finally,
 the values of temperature and humidity range are included which are the
 maximum - the minimum values per day.