Red-backed Shrike and bumble-bee. Layout drawing for the illustration (top left) on page 54 of Tracks. The pencil notes (on the length of the primaries, emargination, tail shape, bill structure, and the plumage of the female) read: 1st = PC I (primary covert I); 2 shorter than 4; 3 longest; 4 next; [?] + 3 s [?] II;
3-4 emarginated outer webs; tail square except outer pair 10 mm shorter; hooked at tip; notch + tooth; female grey rump + female crown nape often tinged grey. On the back of a letter from George Rainbird Ltd. enclosing a proof of one of the advertisements in the Shell Bird Sanctuaries series. 170 x 230 mm.

The drawing was inspired by Niko Tinbergen's photograph (left) of a bumble-bee impaled on barbed wire.

Photograph of bumble-bee © Jaap Tinbergen / Oxford University Press 1967

Other images © The Estate of E A R Ennion / Oxford University Press 1967

Long-eared Owl feeding on young rabbit. Layout drawing for the illustration (left) on page 58 of Tracks. This female frequently took small rabbits and their empty 'masks' lay below her chosen tree in a Northumberland fir wood.

On the back of a letter from Urchfont Manor college of adult education: "I did nothing about the film... so we must hope for good weather". 105 x 120 mm.