| 1985 | 1989 | 1991 | 1999 |
 |
 |
 |
 |
| SG 1160 | SG 1322 | SG 1620 | SG 2853 |
| Scott 981 | Scott 1125 | Scott 1345ag | Scott 2129b |
| Imperf | MS | MS | |
| Barred Owl | Barred Owl | Pel's Fishing Owl | Tawny Owl |
| 2000 | 2004 |
 |
 |
| SG 3014 | SG 3406 |
| Scott 2172 | Scott 2416 |
| African Wood Owl | Barn Owl |
| 2001 |
 |
| SG 3103/8 |
| Scott 2212 |
| Stylised Owl |
| 2002 |
 |
| SG MS3341a |
| Scott 2342 |
| Rufous Fishing Owl |