Kangaroo rats may be easily eradicated by the use of the poisoned grain
used for prairie-dog control by the Biological Survey and the University
of Arizona Extension Service. This can be obtained by application to the
State representative of the Biological Survey or to the local county
agricultural agent, or may be mixed as follows:
_Formula for poisoned bait._--Dissolve 1 ounce of strychnine
sulphate in 1-1/2 pints of boiling water. Add 1 heaping
tablespoonful of gloss starch, previously mixed with a little cold
water, and boil until a clear paste is formed. Add 1 ounce of
baking soda and stir to a creamy mass. Add 1/2 ounce of glycerine
and 1/4 pint of corn sirup and stir thoroughly. Pour over 16 quarts
of rolled barley and mix well until every grain is evenly coated.
Allow to dry before using.
In bushel quantities use as above directed, 2 ounces of strychnine,
2 ounces of soda, 1 ounce of glycerin, 1-1/4 ounces of starch,
1-1/2 quarts of boiling water, and 5/8 pint of corn sirup.
Scatter poison, when the natural food of the kangaroo rat is
scarce, on clean hard places near the holes, 1 quart to 50 holes.
If powdered strychnine alkaloid is used, prepare the hot starch
paste first. Then sift strychnine and baking soda, previously
thoroughly mixed, into the hot starch paste and stir to a creamy
mass. Proceed as in the above directions with sirup, glycerin,
etc.
Use this poison within five days after mixing or retain in
air-tight containers.
_Caution._--All poison containers and all utensils used in the
preparation of poison should be kept _plainly labeled_ and _out of
reach of children_, irresponsible persons, and live stock.
A spoonful of the poisoned grain scattered about the used entrances
of a mound is sufficient, and prebaiting is not necessary, as with
prairie dogs.
A word of caution should perhaps be offered in connection with control
measures. As man has come to occupy a greater portion of the earth's
surface, and as he has become more and more the master of his
environment, he has inevitably disturbed the relationships of the birds
and mammals about him, has upset the balance of nature. If he kills the
carnivorous species because of their depredations on game and live stock
he must be prepared to cope with the increased hordes of rodents which
feed on vegetation and on which the carnivorous animals act as a check.
If he destroys the rodents, he may remove the checks on certain noxious
plants or insects. One control measure often necessitates the adoption
of another.
This is not to argue against control measures, for if our harmful
species were not controlled, agriculture in many sections would be
impossible. Control measures, however, should be scientifically founded
and applied. The indiscriminate slaughter of supposedly harmful species
of birds and mammals in the guise of benefiting agriculture may do far
more harm than good. Many of the species which do some harm do far more
good. The exact status of each suspected species should be carefully
determined through an adequate scientific investigation. If the species
is condemned, sound control measures should be thoroughly applied.
In grazing districts or in areas devoted to intensive agriculture the
death sentence should probably be passed on the banner-tailed kangaroo
rat. It should be recalled, however, that this is the largest and one of
the handsomest of all its family, and that it is one of the most
characteristic and interesting of all the desert fauna; where extensive
grazing or agricultural operations are not undertaken, therefore, we
feel that the kangaroo rat should be let alone, unless its presence
threatens infestation of valuable agricultural or grazing lands.