The lapwing nest you flagged on Tuesday had four eggs at temperature. Friday morning the camera card shows a Marsh Harrier at 04:17 and by the time you arrive at 08:30, the eggs are gone and there are fragments of shell twelve centimeters to the south. That sequence needs to be in the record — the nest final status, the predator ID, the exact egg count at last known good check, the egg status progression — because in two years you'll want to know whether depredation events cluster in specific meadow habitats or correlate with specific grid positions.
When the SD Card Round Goes Wrong
Camera trap fieldwork in a 25-grid meadow system is a logistics operation before it's a biology operation. Each visit involves pulling cards, replacing cards, checking batteries, and logging what went where — and the SD card rotation is where data chains break if the tracking system fails. A card labeled "out" from grid position 14 that gets reinserted into grid 9 without a record update produces corrupted provenance for every event file on that card.
This template handles the hardware audit explicitly. Camera_Nr is the physical trap identifier. SDCard_Nr_In and SDCard_Nr_Out are separate text fields — the card going in and the card coming out are two distinct entries because they're two distinct physical objects. Changed Batteries is a yes/no flag per visit. The Action field — SD card replaced, put cameratrap, removed cameratrap, control, nestcamera info — logs exactly what happened during the visit, not just that a visit occurred.
Grid or Nest distinguishes the operational mode: the same template record covers both a standard phototrap grid check and a nestcam deployment. MeadowID and Grid ID anchor the spatial position. UTM and Coordinates (GPS location field) provide GIS-ready coordinate data per record.
Egg Status Vocabulary Is Not Optional Metadata
The Eggstatus field carries the full controlled vocabulary that ornithological nest monitoring requires. "Warm; also when you see a bird flying off the nest" — "breaks, no holes" — "holes" — "hatching" — "cold, laying phase" — "depredated: broken eggs in nest or close by, with egg rests (e.g. blood, yolk) in shells" — "hatched: broken eggs in nest, no egg rests in shells." The distinctions between these states are not pedantic. A hatched nest and a depredated nest with complete shell removal look identical in the field without the egg remnant evidence. A record that says "no eggs, no shells" without the controlled vocabulary entry leaves the outcome ambiguous.
Nr_Eggs is an integer count per visit. FinalNestStatus closes the nest record with the definitive outcome: hatched, depredated, abandoned, lost to agricultural activity, eggs collected for research. The difference between "depredated" and "lost: all eggs lost due to direct agricultural activity (e.g. mown over)" is a conservation management distinction, not just a classification detail.
The Nesthabitat field records the vegetation structure at nest position: short grass unmown, half-high grass unmown, long grass unmown, grass island in mown meadow (large/small), arable land, maize, mowed meadow, grazed meadow. Lapwing nest success rates across these habitat classes are exactly the kind of management-relevant finding that drives subsidy allocation decisions in Dutch agri-environment schemes.
The Predator Column Across a Season
PredatorID covers fifteen aerial predator species common in northwest European meadow systems — Lesser Black-backed Gull, Marsh Harrier, Common Buzzard, White Stork, Peregrine Falcon, Eurasian Sparrowhawk — annotated with Dutch common names. When you filter depredated final nest status events by PredatorID and nest habitat across a full season, you're building the predator-habitat interaction dataset that camera trap deployment was designed to generate.
Species — Lapwing, Oystercatcher, Redshank, Avocet — links the nest record to the focal species. Researcher and Researcher2 integer fields log observer IDs, which matters for inter-observer reliability assessment when fieldwork teams rotate across the monitoring grid.