Hypothetically, I am trying to make a graph representing the abundance of 4 species in a quadrat. I want to display this as a % of the total number each species represents. Here is an example dataset:
Rep 1 Rep 2 Rep 3 Total
Species 1 10 32 21 63
Species 2 2 19 10 31
Species 3 27 28 20 75
Species 4 21 8 19 48
217
Below I have worked out the table with the values displayed as percentages. I have then made a 'mean' percentage, which is made from the rep 1-3 % for each species.
Rep 1 Rep 1 As % Rep 2 Rep 2 As % Rep 3 Rep 3 As % Mean of all %'s
Species 1 10 16.67% 32 36.78% 21 30.00% 29.03%
Species 2 2 3.33% 19 21.84% 10 14.29% 14.29%
Species 3 27 45.00% 28 32.18% 20 28.57 34.56%
Species 4 21 35.00% 8 9.20% 19 27.14% 22.12%
Totals: 60 100.00% 87 100.00% 70 100.00% 100.00%
I'd like to display this as a graph to show the average % that this species was viewed in each rep. Therefore I need SD or SE to show how much the % values varied around the mean. If I just calculate SD using the same values as I did for the mean will this work? I'm just not certain as it is a % I'm not sure if it would be changing what the SD is technically showing?
EDIT: Major edit to try and clear it up.