SolarNight   bool    `json:"solar_night"`
	CivilNight   bool    `json:"civil_night"`

	SolarNight    bool    `json:"solar_night"`
	CivilNight    bool    `json:"civil_night"`
	DiurnalActive bool    `json:"diurnal_active"`

	if dawn, ok := sunTimes[suncalc.Dawn]; ok && !dawn.Value.IsZero() {
		if sunset, ok := sunTimes[suncalc.Sunset]; ok && !sunset.Value.IsZero() {
			output.DiurnalActive = !midpoint.Before(dawn.Value) && !midpoint.After(sunset.Value)
		}
	}

		if day && result.SolarNight {

		if day && !result.DiurnalActive {

			if config.Day && result.SolarNight {

			if config.Day && !result.DiurnalActive {

"5": "Gecko"

"5": "Gecko"

## [2026-04-18] `--day` redefined as civil dawn → solar sunset (includes dawn chorus)
`--day` previously filtered to solar day (sunrise → sunset), excluding the dawn chorus.
Changed to civil dawn → solar sunset so diurnal species active at dawn are included.
`--night` (solar night) is unchanged. The dawn-chorus window (civil dawn → solar sunrise)
is now covered by **both** flags — a recording at that time is `solar_night=true` and
`diurnal_active=true`. Correct: kiwi and diurnal bird-song both overlap at dawn.

`IsNightOutput` gains a new `diurnal_active` field (bool, present in JSON output of
`skraak isnight`) computed as `midpoint >= civil_dawn && midpoint <= solar_sunset`.
**Files changed:** `tools/isnight.go`, `tools/calls_clip.go`, `tools/calls_classify.go`

  --filter <filter> --species <species> --size 448 --color

  --filter <filter> --species <species> --size 448 --color [--night --lat <float> --lng <float> --timezone <Pacific/Auckland>] #timezone required for DOC AR4 recorders

## Step 3.5: Day/night pre-filter (skip if target is "either")

Fallback Locations:

Sites:

Calibrate once per folder with a representative WAV:

```bash
./skraak isnight --file <wav> --lat <lat> --lng <lng> --timezone Pacific/Auckland
```
Use the returned `sunrise_utc` / `sunset_utc` (convert to Pacific/Auckland) as cutoffs for the whole folder. For each PNG, parse `YYYYMMDD_HHMMSS` from the basename, add `START` seconds. Drop PNGs in the wrong half for the target's diel pattern. Report kept/dropped.