Trap Catch Per Trap Night Term Tool

Description

trapNights = traps*nights*functioningFraction; catchPerTrapNight = catchCount/trapNights.

Insect sampling effort can be expressed as trap-nights, active hours, flower-minutes, distance or area-times-beats. Normalizing catch by effort makes its denominator explicit, but does not automatically estimate abundance or equalize detection.

trapNights = traps*nights*functioningFraction; catchPerTrapNight = catchCount/trapNights.

When to use this tool

Use Trap Catch Per Trap Night Term when normalizing a supplied catch, visit count or sampling exposure.

How to use the tool and how it works

Enter catchCount, traps, nights, functioningFraction. Use the units and conventions below.
Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
Read trapNights, catchPerTrapNight. Use the output convention below.

Require nonnegative whole catchCount, positive whole traps, positive nights and functioningFraction in (0,1]. trapNights = traps*nights*functioningFraction; catchPerTrapNight = catchCount/trapNights.^[1]

Input field	Meaning and units	Accepted input
catchCount	Catch Count	Required. Safe integer; minimum 0.
traps	Traps	Required. Safe integer; minimum 1.
nights	Nights	Required. Finite number; strictly above 0.
functioningFraction	Functioning Fraction	Required. Finite number; maximum 1; strictly above 0.

Output field	Interpretation	Returned shape
trapNights	Trap Nights	Required. Finite number.
catchPerTrapNight	Catch Per Trap Night	Required. Finite number.

json

{
  "input": {
    "catchCount": 120,
    "traps": 10,
    "nights": 3,
    "functioningFraction": 0.8
  },
  "output": {
    "trapNights": 24,
    "catchPerTrapNight": 5
  }
}

Limitations and assumptions

The fraction is an assumed effective-functioning adjustment. Catch rate is not abundance or detection probability, and uniform effectiveness is not verified.
Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.

Alternative or Complementary methods

Use a suitable sampling and detection model for abundance inference, and review actual deployments and conditions before aggregating effort.

References

Calculation and input contract: entomology/trap-catch-per-trap-night-term — tool.io

Similar or alternative tools

Trap Night Valid Exposure
Return trapNights as their dot product, summing validNights[i]*traps[i].
Trap Exposure Day Fraction
equivalentDays = sum(activeHours)/suppliedHoursPerDay.