Thank you for your reply and your suggestions to visualize the codes. I tried to update it according to your suggestion but for a new user there is a restriction to add only one graph. I am trying to copying it in following:
Basic plots codes:
SUR_MONTHS <- read.csv("F:/SUR_MONTHS.csv")
SUR_MONTHS$Months <- factor(SUR_MONTHS$Months , levels=c("OCT", "NOV", "DEC", "JAN", "FEB", "MAR"))
boxplot(SUR_MONTHS$Counts ~ SUR_MONTHS$Months , ylab="Counts" ,
xlab="Months of the winter season")
Basic plot's graph:
As there are some restrictions for the new user so, please find the basic R plot that I have added in my main question ask section and the ggplot's graph in the following.
ggplots codes:
library(ggplot2)
SUR_MONTHS$Months <- factor(SUR_MONTHS$Months)
my.bp <<-ggplot(data=SUR_MONTHS, aes(y= Counts, x=Months, fill=Months ))
my.bp <- my.bp + geom_boxplot()
my.bp <- my.bp + ylab("Counts of Species") + xlab("Months")
my.bp
ggplots graph:

So, my question is when I ran the basic boxplot, the observation for the October and November were different and there were not outlier in the month of March. But, why this kind of differences happening in the ggplots with the basic plots?