Bat sampling
To capture bats we used three mist nets (12 X 2.5 m, 9 X 2.5 m and 6 X 2.5 m) in each site. Mist nets were
opened every day at dusk and checked every 30 minutes for 6 hours each sampling night. This was repeated
every month in each site, two or three consecutive nights of the new moon from April to August 2012.
There was a total of 41 sampling nights: 18 nights during the rainy season and 23 nights with scattered
precipitation. The bat sampling effort by site in a night was 405 m2net-hours, which represents a total of
34,020 m2net-hours sampling effort. Captured bats were identified taxonomically by their external features
[35], marked with indelible ink in order to avoid multiple counting, and all individuals were released after
data and photographs were taken. For capture and handling bats, we obtained the approval of the director
of El Ocote as well as the local people in the study area.
Distribution of the data on bat captures was verified by the Kolmogorov-Smirnov normality test.
Considering the non-normal distribution of the data, the Wilcoxon rank test was used to compare average
bat richness between control sites and treatment sites. Additionally, we used a Chi-square test to verify if
the presence of fruits influenced species abundance in treatment sites. This test was applied in cases of
those bat species of more than five individuals captured at both control sites and treatment sites.
To evaluate the importance of each bat species as a seed disperser agent, we modified the Disperser Index
of Importance (DII) [36] and proposed the formula: DIImod=(S*B*P)/1000, where, S is the percentage of
fecal samples from each species of bat that contain seeds out of the total fecal samples collected, B is the
percentage of individuals captured from one bat species out of the total number of all individuals captured,
and P is the proportion of plant species dispersed by each species of bat out of the total number of plant
species dispersed by all bats recorded. To determine the P value, each fecal sample with at least one seed
was counted as an event, the samples with seeds from two species as two events, and so on. The value
rank goes from 0 to 10.
Bat fecal samples
We put a plastic strip (12 X 1 m) under each mist net to collect fecal samples of tangled bats, in order to
identify the individual that produced the scats by looking for seed remains on the bat and net or by the
vertical position under the bat [37]. The captured individuals were placed in fabric bags during
morphometric data registration, which helped to obtain more samples. Every fecal sample was put
individually inside a wax paper bag labeled with the date, treatment and bat species.
To determine the diet of captured bats, we made a list of the plant species dispersed by each bat species
recorded. The seeds were classified into the following successional categories: pioneer and persistent,
along with their growth forms: herbs, shrubs and trees. We looked for food preferences of bats by
performing a correspondence analysis on the contingency table showing the frequencies of seeds
encountered in feces of the three bat species with the most fecal samples [38].
Seed rain sampling
During the same bat samplings nights, four seed collectors were set in each study site; each collector was
a round piece of plastic 2 meters in diameter and black in color to avoid any light reflection that could scare
away the bats. Each collector was hung from the vegetation at 50 cm above the ground during bat
sampling. The seed-rain sampling effort by site each night was four collector-hours, and the total sampling
effort was 2,016 collector-hours. From the seed-rain obtained, we only looked for seeds embedded in fecal
material.
Bat samplingTo capture bats we used three mist nets (12 X 2.5 m, 9 X 2.5 m and 6 X 2.5 m) in each site. Mist nets wereopened every day at dusk and checked every 30 minutes for 6 hours each sampling night. This was repeatedevery month in each site, two or three consecutive nights of the new moon from April to August 2012.There was a total of 41 sampling nights: 18 nights during the rainy season and 23 nights with scatteredprecipitation. The bat sampling effort by site in a night was 405 m2net-hours, which represents a total of34,020 m2net-hours sampling effort. Captured bats were identified taxonomically by their external features[35], marked with indelible ink in order to avoid multiple counting, and all individuals were released afterdata and photographs were taken. For capture and handling bats, we obtained the approval of the directorof El Ocote as well as the local people in the study area.Distribution of the data on bat captures was verified by the Kolmogorov-Smirnov normality test.Considering the non-normal distribution of the data, the Wilcoxon rank test was used to compare averagebat richness between control sites and treatment sites. Additionally, we used a Chi-square test to verify ifthe presence of fruits influenced species abundance in treatment sites. This test was applied in cases ofthose bat species of more than five individuals captured at both control sites and treatment sites.To evaluate the importance of each bat species as a seed disperser agent, we modified the Disperser Indexof Importance (DII) [36] and proposed the formula: DIImod=(S*B*P)/1000, where, S is the percentage offecal samples from each species of bat that contain seeds out of the total fecal samples collected, B is thepercentage of individuals captured from one bat species out of the total number of all individuals captured,and P is the proportion of plant species dispersed by each species of bat out of the total number of plantspecies dispersed by all bats recorded. To determine the P value, each fecal sample with at least one seedwas counted as an event, the samples with seeds from two species as two events, and so on. The valuerank goes from 0 to 10.Bat fecal samplesWe put a plastic strip (12 X 1 m) under each mist net to collect fecal samples of tangled bats, in order toidentify the individual that produced the scats by looking for seed remains on the bat and net or by thevertical position under the bat [37]. The captured individuals were placed in fabric bags duringmorphometric data registration, which helped to obtain more samples. Every fecal sample was putindividually inside a wax paper bag labeled with the date, treatment and bat species.To determine the diet of captured bats, we made a list of the plant species dispersed by each bat speciesrecorded. The seeds were classified into the following successional categories: pioneer and persistent,along with their growth forms: herbs, shrubs and trees. We looked for food preferences of bats byperforming a correspondence analysis on the contingency table showing the frequencies of seedsencountered in feces of the three bat species with the most fecal samples [38].Seed rain samplingDuring the same bat samplings nights, four seed collectors were set in each study site; each collector wasa round piece of plastic 2 meters in diameter and black in color to avoid any light reflection that could scareaway the bats. Each collector was hung from the vegetation at 50 cm above the ground during batsampling. The seed-rain sampling effort by site each night was four collector-hours, and the total samplingeffort was 2,016 collector-hours. From the seed-rain obtained, we only looked for seeds embedded in fecalmaterial.
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