Put a basic infrared camera low, near a confirmed sighting, with a view of the way in and out. Then study every photo on a big screen.
What a camera can tell you
A trail camera answers three questions: is this my pet, when does it come, and which way does it go? Use one once you have a place worth watching, such as a repeat sighting, a gap under a fence, a shed door or a spot where food keeps going. It watches a few feet of ground, so it will not find a pet that could be anywhere. Basic models are enough. Lost Dogs of Wisconsin, a volunteer group that uses them on real searches, tells owners to beg, borrow or buy one, and says simple models work well. Most of the advice below comes from that group or from camera makers, so treat it as practical guidance rather than research. Camera makers have products to sell, and their range figures are claims.
Choosing a camera
You need four things: day and night images, an infrared flash, a date and time stamp, and a memory card slot. Ask your shelter or lost pet group first, because one may have a camera to lend. Beyond that, one choice matters. Low-glow cameras use 850 nm infrared, which gives a longer flash range but a faint red glow. No-glow cameras use 940 nm, which is close to invisible but has a shorter range, and makers admit that neither guarantees an animal will not notice. For a nervous pet at close range, a no-glow model is a reasonable pick. Cellular cameras send pictures to your phone, which means fewer trips to the site. They may need a subscription, and they need signal at that exact spot, so check your phone’s bars there first.
Specs that matter and specs that do not
Ignore the biggest number on the box. Megapixels matter less than clear night pictures. Detection range and flash range are separate figures, and they can differ. One maker’s own example describes a 100-foot sensor with a 60-foot flash, so a pet passing at 90 feet sets off the camera and gives you a black picture. For this job, you will be working close, so long range is not worth paying for. Trigger speed matters more, because it is the gap between the sensor firing and the picture being taken, and a pet moving through can leave the frame in that time. A short video clip after each trigger shows direction better than a still.
Where to put it
Think about the route rather than the bowl. A fence gap, the end of a hedge, a path along a creek or the edge of a field are all natural funnels. Place the camera so it looks along the route or at a slight angle, and leave enough distance to see where your pet comes from and goes to. One camera guide suggests about 10 to 16 feet from the camera to the point of interest for medium and large mammals, which is a starting point for a dog. Go closer for a cat. Mount it lower rather than higher, since manuals are written for deer. Lost Dogs of Wisconsin suggests a tree, an upturned crate or a simple stand. Ask permission on private land, and do not aim it at someone’s windows, door or yard.
Set it up right the first time
Use fresh batteries and an empty memory card, and set the date and time before anything else, because a wrong clock ruins your time stamps. Sensors react to a change in heat against the background, not simple movement. A warm animal shows up well on a cold night, and less well on a hot day when the ground is close to body temperature. The top of the picture is often outside the sensor’s coverage, which is why height and aim matter. So test it. Walk or crawl through the frame at pet height, then check the card. Trim swaying grass or leafy branches if you get empty shots, but disturb the place as little as you can. Expect to adjust the aim over the first few days.
Checking without spooking your pet
Go once a day at most, at a quiet time, and move slowly. If you bring food and water, combine the trips. Lost Dogs of Wisconsin suggests swapping the card for a blank one and taking the full card home, which keeps you from standing around at the site. You can also make a track patch. The same group suggests wet sand or mud, or ash or cornstarch dusted on the ground, so a paw print will show.
How to read the photos
Look at every photo, starting with the first ones after setup. The Wisconsin group reports a search in which early images were overlooked for months because the team assumed the sightings had started later. Use a computer, in a dark room, and lighten the picture in any basic photo editor. Night images are black and white or show odd colors, so a brown dog may look pale, and camera height changes how big an animal looks. Compare the shape instead: ears, tail set, legs, any mark or collar. A dog making a quick grab may show up only as a tail or an ear, and a partial shot may still be your pet. Skunks, raccoons and cats in the frame do not mean your pet will not come.
Turn pictures into a plan
Write down the date, time and direction for each visit. Dawn and dusk are common, the Wisconsin group says, though not always daily at first. Once you have two or three visits at similar times, you have a schedule, and you can decide what to do next. Add the sightings to your map, as in our post on how to map lost pet sightings, and move your posters there. Do not rush in with a crowd the moment you see your pet. Ask your local lost pet group or shelter whether the next step is a quiet sit, a feeding routine or a humane trap. If a photo shows a limp or a wound, send it to your vet and ask how urgent it looks.
Sources
Lost Dogs of Wisconsin, trail cameras: lostdogsofwisconsin.org/post/trail-cameras-help-monitor-lost-dog-behavior-part-7-in-a-series. Lost Dogs of Wisconsin, monitoring your station: lostdogsofwisconsin.org/post/monitoring-your-feeding-station-part-8-in-series. Lost Dogs of Wisconsin, check your photos: lostdogsofwisconsin.org/post/check-your-trail-camera-photos-carefully. NatureSpy, detection zones: naturespy.org/blogs/help-articles/trail-camera-detection-zones-explained. GardePro, PIR sensors: gardepro.com/blogs/gardepro-blogs/trail-camera-pir-sensor-guide. GardePro, specs: gardepro.com/blogs/gardepro-blogs/trail-camera-specs-explained.