Enrichment · Passion Projects

Count what lives
in a 2 by 2 meter square.

Mark out a plot, set a timer and tally every plant, insect, spider and snail you find, by name or by look-alike group. The page turns the tally into the numbers ecologists use: species richness, Simpson’s index of diversity and the Shannon index, and ranks your sites so you can compare a lawn with a garden or a pond edge.

Start a surveyWhat you get
$5one-time · every device you sign in on
Buy · $5

Included with the Caveat Academy pass and Whole-school licenses. Or get it in the Passion projects kit, $39 for 48 items.

Surveys

The worked example is made up: three 4 m² plots around one school. Saved on this device only.

Loading the survey form. If nothing appears, turn on JavaScript.

What you get

Enrichment · Passion Projects$5

What you finish with
A survey record per site: habitat, plot size, search time, weather and a tally by species or look-alike group. Works out richness, individuals, Simpson’s index, the Shannon index and the most common species’ share; ranks sites by Simpson’s index and counts different species across all surveys.
Who it is for
Middle and high school students doing a field study or science fair project, environmental clubs and science teachers running a schoolyard survey.
Format
Browser survey record with a saved entry per site. Prints one survey, all surveys in a table or a blank field sheet to take outside; downloads a spreadsheet (.csv); exports and imports a file.
Access
$5 one-time, yours on every device you sign in on; the tool opens once you are signed in with it. Included with the Caveat Academy pass and Whole-school licenses. Also in the Passion projects kit ($39) and the Enrichment Suite pass ($119), and 1 more bundle. Everything you type stays in this browser; nothing is sent to Caveat.
Where it lives
The Passion Projects space in Caveat Enrichment.
Support
Questions about access, an order or a correction: team@caveatacademic.com.

How to use it

  1. Mark a plot of the same size at each site, such as 2 by 2 meters, and set a timer for the same number of minutes.
  2. Search the plot and tally each kind you find, by name or a look-alike name you use consistently.
  3. Enter the site, habitat, plot size, minutes and weather, then the tally.
  4. Read the results line: richness, individuals and both indexes.
  5. Survey two or more sites the same way and compare them in the side panel.

Start a survey

How the diversity numbers work

Three numbers from one tallyRichness (S)How many differentspecies you foundPond edge: 7Ignores how many of eachSimpson’s indexChance two individualspicked at random aredifferent species1 − Σ n(n−1) ÷ N(N−1)Pond edge: 0.84, field:0.22Shannon index (H′)Richness and evennesstogether−Σ p ln p, with p = n ÷NPond edge: 1.79, field:0.43Three numbers from one tallyRichness (S)How many different species you foundPond edge: 7Ignores how many of eachSimpson’s indexChance two individuals picked at random aredifferent species1 − Σ n(n−1) ÷ N(N−1)Pond edge: 0.84, field: 0.22Shannon index (H′)Richness and evenness together−Σ p ln p, with p = n ÷ NPond edge: 1.79, field: 0.43
Both indexes rise when there are more species and when individuals are spread more evenly among them. Compare sites only when the plot size and search time match.

Richness and evenness

A site with ten species, nine of them single individuals and one with ninety, is less diverse in practice than a site with ten species of ten each. Diversity indexes reward both more species and a more even spread.

Simpson’s index

The version used here, 1 − Σ n(n−1) ÷ N(N−1), runs from 0 (one species) toward 1 (many, evenly spread). It is the chance that two individuals drawn without replacement belong to different species.

A fair comparison

Use the same plot size, the same search time and similar weather at each site, and survey at the same time of day. Do not collect or harm what you find; look, count and leave it.

Sources

  1. Simpson, E. H. (1949). Measurement of diversity. Nature, 163, 688.
  2. Shannon, C. E. (1948). A mathematical theory of communication. Bell System Technical Journal, 27, 379 to 423.
  3. Magurran, A. E. (2004). Measuring Biological Diversity. Blackwell.
  4. National Park Service: BioBlitz and citizen science field methods (nps.gov).

The worked example is made up. Indexes are computed in your browser and pinned to a Python reference. Nothing you type is sent to Caveat. Support: team@caveatacademic.com.