Niche Overlap Calculator
Calculate niche overlap indices to analyze competitive interactions between species sharing resources.
Resource Usage Data
For calculating resource electivity/selection
Quick Examples
Pianka's O: Sum(p1i x p2i) / sqrt(Sum(p1i²) x Sum(p2i²))
Values range from 0 (no overlap) to 1 (complete overlap)
Competition Assessment
High Competition Risk
0.8111
Pianka's Overlap
0.7000
Schoener's Overlap
Overlap Indices
Pianka's Index
0.8111Symmetric overlap
Schoener's Index
0.7000Percent overlap
Morisita's Index
0.8111Sample size independent
Horn's Index
-0.0795Information-theoretic
Niche Breadth
Species 1 Levins' B
4.444
Std: 0.861
Species 2 Levins' B
4.444
Std: 0.861
Species 1 Shannon's H
1.544
Species 2 Shannon's H
1.544
Resource Usage Comparison
ResourceSp1 %Sp2 %Electivity
Food A30.0%10.0%0.200 / -0.333
Food B25.0%15.0%0.111 / -0.143
Food C20.0%25.0%0.000 / 0.111
Food D15.0%30.0%-0.143 / 0.200
Food E10.0%20.0%-0.333 / 0.000