As Spring approaches, his obsession with the Pee-wit awakes. It demands a whole plan of campaign before Mulder can go to work . The Pee-wit is a difficult bird to observe and to photograph, so “we have to “open a box of tricks”” . Mulder goes into the fields with an imitation camera, which he places at a long distance from the nest. Every day he brings the camera closer to the nest so that the Pee-wit will become accustomed to the strange object. At last the imitation camera will be replaced by a real camera which will be placed on the nest and is worked by remote control. Mulder is very careful not to disturb the nest and while the bird is away, he rests the camera on the nest . To focus the camera clearly, he uses a checked tea cloth , rolled into a ball, in place of the bird, getting a sharp definition on the checks. before removing it. Mulder uses binoculars to watch for the bird’s return and to see that she has settle on the nest. After the bird has been on the nest for 30 minutes and the eggs are completely warm he can take the photograph. Of course, the bird will fly off the nest but she returns immediately so the eggs are not harmed..

Mulder uses a very unusual “technique” to study the Grebe. He uses his canoe, approaching the nest with the camera each day “until it seems that they lie together on one pillow”. The patience and perseverance used to achieve these remarkable wild life photographs are evident in the outstanding details in the paintings.