h. Two fumigants are commonly used against rodents.
(1) Calcium cyanide is a chemical that produces hydrogen cyanide gas
when exposed to the moisture in the atmosphere. The liberated gas is extremely toxic
to all forms of animal life. The operation is dangerous and only trained personnel are
allowed to carry it out. Gas masks are a must! It is one of the fastest acting fumigants
known. A large dose will render the victim immediately unconscious followed by a quick
death. Smaller lethal doses will initiate throat constriction, nausea, hyper blood
pressure, cardiac depression, and finally death by respiratory failure.
(2) Carbon monoxide is sometimes used against rodents usually when other
fumigants are not available, or when burrows are known to exist with rodents inhabiting
them. The carbon monoxide gas is pumped into the burrow and causes death in
approximately 10 minutes caused by the inability of the blood to carry oxygen to the
cells. It can be called a blood poison.
a. The third phase of rodent control is termed mechanical control. This utilizes
traps of various kinds to either kill or capture the rodents. Traps are used where
rodenticides are not advisable and as a clean-up operation for animals surviving
poisoning. The advantage of using traps is that no dead animals will be left. The
disadvantage lies in the fact that mass kills are not possible. It takes longer and is less
b. There are four kinds of traps used in rodent control.
(1) Spring traps, commonly referred to as mousetraps, which are used
effectively against mice and small rats.
Snap traps are like the spring traps, only larger, and are referred to as
(3) Steel traps are much like a bear trap; each side of the trap is pulled open
and will catch the rodent usually by the leg.
(4) Cages are sometimes employed when specimens are needed for
identification or other needs. They are baited and have a trip door that is activated once
the animal enters the cage.