| Abstract: | A conventional 35-mm camera equipped with an f2.8 135-mm lens and ASA 64 color film was used to acquire sex ratio data on mallards (Anas platyrhynchos) wintering in the Platte River Valley of south-central Nebraska. Prelight focusing for a distance of 30.5 metres and setting of shutter speed at 1/2000 of a second eliminated focusing and reduced image motion problems and resulted in high-resolution, large-scale aerial photography of small targets. This technique has broad application to the problem of determining sex ratios of various species of waterfowl concentrated on wintering and staging areas. The aerial photographic method was cheaper than the ground ocular method when costs were compared on a per-100 bird basis. |
| Genre: | Article |
| ProdID: | 1001697 |
| Citation Author: | Ferguson, E. L.; Jorde, D. G.; Sease, J. L. |
| Citation Contributing Office: | |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | |
| Citation Editor: | |
| Citation End Page: | 827 |
| Citation Issue: | 6 |
| Citation Keywords: | |
| Citation Language: | English |
| Citation Larger Work Title: | Photogrammetric Engineering and Remote Sensing |
| Citation LatN: | |
| Citation LatS: | |
| Citation LonE: | |
| Citation LonW: | |
| Citation Month: | |
| Citation No Pagination: | |
| Citation Number Of Pages: | 4 |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | p. 823-827 |
| Citation Projection: | |
| Citation Public Comments: | |
| Citation Publisher: | |
| Citation Series: | |
| Citation Series Code: | |
| Citation Series Number: | |
| Citation Search Results Text: | Use of 35-mm color aerial photography to acquire mallard sex ratio data; 1981; Article; Journal; Photogrammetric Engineering and Remote Sensing; Ferguson, E. L.; Jorde, D. G.; Sease, J. L. |
| Citation Start Page: | 823 |
| Citation Volume: | 47 |
| Citation Year: | 1981 |
| Type: | citation/reference |
| Text: | Use of 35-mm color aerial photography to acquire mallard sex ratio data; 1981; Article; Journal; Photogrammetric Engineering and Remote Sensing; Ferguson, E. L.; Jorde, D. G.; Sease, J. L. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Thu, 1 Jan 1981 00:00 -0600 |
| Publisher: | |
