Cannon netting

Rocket nets and cannon nets are types of animal traps used to trap a large number of live animals, usually birds, but they also have been used to catch large animals such as various species of deer. Rocket nets, cannon nets, and other net launching devices are built upon similar principles have been used since the 1950s (Dill and Thornsberry 1950, Hawkins et al. 1968, Grubb 1988 and 1991).

Rocket and cannon nets are used in conservation programs where a large number of live animals need to be captured for analysis, veterinary care or relocation.

The Rocket Net consists of an accordion folded rectangular net with one edge attached to the ground by short ropes or shock cords. The net can be placed directly on the ground in a line or can be folded and placed in a specially designed box (Grubb 1988). Nets specifically designed for rocket nets can be purchased from several wildlife supply and net manufacturers.

The rockets are constructed from heavy gauge metal pipes with caps threaded and welded on one end with a removable cap on the opposite end that contains ports for the expanding gasses to escape. The rocket charges are made from black powder and an electric match enclosed that is used to ignite M6 Howitzer propellant. All 3 components are enclosed in a larger plastic bag with shunted leg wires extending out of the bag. Currently the primary manufacturer of rockets for rocket nets is WinnStar in Illinois.

In addition to the rocket net, other specialty equipment is necessary for the safe firing and storage of rocket nets and their charges. A blasting galvanometer, capacitor discharge machine, and electrical blasting line are recommended for the safe use of this equipment. In addition, an IME-22 container is necessary for the safe transportation of charges and an explosives magazine is required for long-term storage. Transportation and storage of the charges are regulated by the US Department of Transportation; Department of Alcohol, Tobacco, Firearms and Explosives; and by other state and local agencies (ATF: Explosives Law and Regulations, ATF P 5400.7 and 29 CFR, Part 1910.109 and IME Safety Library Publication Numbers 1,3,12, 22, and 14). The US Fish and Wildlife Service and State Wildlife Agencies regulate their use to capture birds and other wildlife.

Cannon nets are similar to rocket net except a cannon-net projectile is a heavy metal barrel which is fired from a launch-rod attached to a metal plate. Cannon propellant is smokeless gunpowder ignited by an electric match. The primary advantage of cannon nets is the lack of explosives, therefore storage and transportation is easier. However, cannon-net projectiles have to be cleaned after every use. A full-sized cannon-net may utilise four or more cannons to pull the net over the target birds. Smaller nets with fewer cannons may also be used.

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