Biology Reference
In-Depth Information
Box 3.7.
The virtual fence
Researchers at CSIRO have applied technology from the new millennium to the
humble farm fence. By fitting cattle with collars containing a global positioning
system (GPS) and a device that can deliver an irritating sound, they have created, in
effect, a virtual fence. Cattle that stray close to the 'fence' are automatically bom-
barded with the annoying sound until they retreat to the desired area. If they hit the
'fence' they receive an electric shock from the collar that is similar to a conventional
electric fence. Researchers found that cattle could learn the whereabouts of the
'fence' in less than an hour. The technology enables a farmer to track stock via the
internet and alter the configuration of fences either manually or automatically. This
could be a valuable tool for regulating stock movements in remnant vegetation or
plantings. While the system is still at a prototype stage, it may become cost-effective
as the cost of the technology decreases relative to the cost of fencing.
Given the importance of fallen timber for many animals, there can be considerable
ecological value in adding old fence posts or even branch trimmings to the ground
layer of plantings. Similarly, the absence of trees with hollows from most plantings
means that nest boxes are of value in revegetated areas to promote the colonisation
of some cavity-dependent animals like gliders and bats.
26, 27
Plantings can sometimes become a refuge for
unwanted pest species on farms. For example, they can
harbour populations of the Red Fox, European Rabbit
and an array of weeds. Activities like ripping rabbit
warrens (but see Box 5.3 in Chapter 5) and laying poison baits for feral predators
are therefore an important part of the management of plantings. Plantings in
Keep dead shrubs and
trees in plantings - don't
remove them
0
5
20
200
800
Number of logs/ha
Figure 3.20:
Relationships between the prevalence of logs in plantings and bird species richness.
