Radar Controlled Hazing Systems

One innovative method to deal with the habituation issue is to use a hazing scheme activated by radar. The theory of radar activated systems is simple. The radar sees birds coming, and the hazing devices are activated in response to specific avian threats. Because the response is a direct result of an action by birds, the birds soon recognize that they are the cause of the activation and learn to avoid the location. In essence these systems seek to use habituation as an ally. Unfortunately, the intricacies of getting a radar to preform accurately, consistently and precisely, and to get a hazing component that has low maintenance and reasonable cost has been difficult.

How it works:

The Radar controlled system uses marine radar to scan the defended area (a pond in excess of 40 acres). Reflected returns (or "hits") are indicated both on the radar screen and with an audible signal. Apparently (I am not privy to exact mechanisms) a computer or audio card "captures" the audio tone and uses it to signal the activation of the hazing devices. These hazing devices are situated surrounding the pond and include devices which shoot screamer shells into the air, lights, and moveable human dummies. This system also incorporates a spraying system to apply a deterrent chemical (Methyl Anthranilate) to the pond.

Effectiveness:

This system was tested for a year but the methods or results of these tests have been unavailable. It is known however that the system has a variety of difficult problems to overcome (most based on the limits of the radar).

Cost:

This system is really quite inexpensive for installation, and is a start toward a viable alternative in defending medium sized (1-25 acres) ponds. However maintenance costs have been reported to be quite high, and consumable supplies such as Methyl Anthranilate and boards with multiple screamer shells mounted on them are expensive, and require a significant amount of human intervention to keep the system "stocked".

Inherent problems:
  • The first problem is one of "false alarms" to the radar screen. While the radar does "see" birds,- it also sees anything capable of sending a return. This includes shoreline, power poles, dikes, dragonflies, waves, anything floating on the surface of the pond etc. If the system was activated on every radar hit., the system would run continuously. In order to deal with this problem the radar is set to only alarm within certain areas or alarm zones. Unfortunately because of ground clutter this the alarm zone coverage to the middle of the pond. This means that birds which approach from a low angle can land on the edges of the pond without being detected. The radar also "sees" rain and snow. During inclement weather, the system would have continuous activation, until the system exhausts consumable supplies. To avoid this problem the system would need to be inactivated or put into a random activation mode, during a time of high probability of bird landings.
  • Another problem is the inability to put hazing devices into the water. A raft floating on the pond would cause constant activation of the radar, and floating platforms are part of a patented system which could present legal problems if copied to closely. This limits the placement of hazing devices to the shore line, and this makes this system questionable for large ponds (bigger than 25 acres). Also since the radar only has 1 or 2 alarm zones it would require a separate radar for each pond that needed to be protected. This would result in radar cross interference in an area with multiple ponds to defend, as well as inflating the costs significantly.
  • Another problem is the inability to determine if this system is effective in reducing mortality. Test data has been unavailable, and the company who designed this system has not used scientifically sound methods of gathering and analyzing the data from previous projects in which they were involved.