While GPS and other technologies reduce labour costs, there are times when those technologies simply don’t work. For example, if animals do not get clear views of the sky then GPS locations may be infrequent or even unobtainable, or the data may not be transmitted far enough. Moreover, often you can get more locations by tracking manually for the same weight of tag by using VHF.
VHF tags allow you to find the your tagged individual in the field which can be important, for example
- to be more exact about the habitat they are using, or find out exactly what they are doing there
- if trying to find a nesting bird,
- to find a freshly dead animal to establish cause of death
- or simply to find animals under cover.
They are therefore ideal for looking at local home-range movements, survival and sociality.
The traditional beeper VHF has advantages over coded VHF when tracking manually; you can tune to an individual frequency and not have interference from other tags, plus the tags pulse quicker which makes direction finding much easier. Nevertheless, they can still be logged using our SRX receivers.
VHF tags require a receiver and antenna to track the tag.
Walls S., Kenward, R. and Holloway, G. 2005. Weather to disperse Evidence that climatic conditions affect vertebrate dispersal. Journal of Animal Ecology 74: 190-197.
Walls, S.S. & Kenward, R.E. 2001. Spatial consequences of relatedness and age in buzzards. Animal Behaviour 61: 1069-1078.
Kenward, R.E., Hall, D.G., Walls, S.S. & Hodder, K.H. 2001. Factors affecting predation by buzzards (Buteo buteo) on released pheasants (Phasianus colchicus). Journal of Applied Ecology 38: 813-822.
Kenward, R. E., Walls, S. S., Hodder, K. H., Pahkala, M., Freeman, S. N. & Simpson, V. R. 2000. The prevalence of non-breeders in raptor populations: evidence from rings, radio-tags and transect surveys. Oikos 91: 271–279.