Testing chemical markers on granivorous birds
- Authors: Steele, G R , Whittington-Jones, Craig A , Craig, Adrian J F K
- Date: 1999
- Language: English
- Type: Article
- Identifier: vital:6936 , http://hdl.handle.net/10962/d1011957
- Description: We tested two substances (oxytetracycline and rhodamine B) that can be added to food or water of free-living birds, and serve as markers in their plumage for later identification. Oxytetracycline produced no detectable changes in the plumage of red bishops or redbilled queleas. Rhodamine B fed to captive birds produced fluorescence in the wing feathers when viewed under ultraviolet light. This fluorescence lasted for at least 14 weeks, and was retained until feathers were moulted. Rhodamine B may thus be useful in identifying birds using a specific feeding site, and for studies of moult and feather growth.
- Full Text: false
- Date Issued: 1999
Clinal morphometric variation in wild honey bees (Hymenoptera: Apidae) in South Africa
- Authors: Steele, G R , Villet, Martin H , Radloff, Sarah E , Hepburn, H Randall
- Date: 1998
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442622 , vital:74015 , https://www.jstor.org/stable/2999809
- Description: As a result of side effects of the accidental dispersal of the Cape honey bee, it has become of agroeconomic importance to delineate the region within South Africa where thelytokous worker honey bees occur so that apicultural movement of bees does not exacerbate the problem. Thelytokous workers are believed to be unique to Apis mellifera capensis, so that the problem is to find morphological markers distinguishing this race from its A. m. scutellata neighbours. However, no evidence of the expected hybrid zone demarcating races could be found. Factor analysis revealed only one spherical cluster of samples. Trend surfaces of the local mean morphometric factor scores showed a cline that paralleled latitude, with distortions relating to montane and continental effects. Discriminant function analysis implicated certain mountain ranges in amplifying the effects of latitude. Trend surfaces of local intercolony factor variance showed morphometric homogeneity across most of the country. We conclude that there is only a single population of honey bees in South Africa, and that it shows climate-correlated clinal variation. If the transportation of bees for commercial apiculture is to be successfully regulated to solve the `capensis calamity', further research should focus on the geographical distribution of thelytokous workers rather than on the capensis phenotype. Such workers have a wider distribution than capensis, occurring also at high frequencies around the type locality of A. m. scutellata.
- Full Text:
- Date Issued: 1998