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diff --git a/59318-0.txt b/59318-0.txt new file mode 100644 index 0000000..377457a --- /dev/null +++ b/59318-0.txt @@ -0,0 +1,593 @@ +*** START OF THE PROJECT GUTENBERG EBOOK 59318 *** + + + + + + + + + + + + +----------------------------------------------------------------------+ + | United States Department of Agriculture | + | Bureau of Biological Survey | + | ------- | + | Wildlife Research and Management Leaflet BS-54 | + +----------------------------------------------------------------------+ + | Washington, D. C. Rev., December 1936 | + +----------------------------------------------------------------------+ + + + RODENT CONTROL AIDED BY EMERGENCY CONSERVATION WORK + + + By Stanley P. Young, Chief, Division of Game Management + + + + +Contents + + Page + + Need for rodent control 1 + Federal, State, and local cooperation 2 + Training of E.C.W. crews 2 + Timeliness of emergency aid 3 + Forest and forage protection 3 + Aid in erosion control 4 + Examples of benefits derived 4 + Safeguarding harmless species 5 + Control work illustrated 6 + Prairie dogs 7 + Ground squirrels 13 + Pocket gophers 15 + Kangaroo rats 20 + Rabbits and hares 25 + Porcupines 27 + A typical E.C.W. crew 30 + + +Need for Rodent Control + +The Emergency Conservation Work Program has been of inestimable value +in the control of prairie dogs, ground squirrels, pocket gophers, +kangaroo rats, rabbits, and porcupines. The citizens of the West have +been forced to carry on campaigns for the control of these rodents +since the settlers first staked out claims on the prairies. To the +agricultural interests of the West the control of rodents is as vital +as is the proper spraying of trees throughout the East to prevent +damage by insects. These small mammals cover the western ranges by +countless thousands, and control is necessary if crops are to be grown. + +Rodent control is nothing new. Records indicate that as early as 1808, +strychnine was shipped by boat around Cape Horn to the Santa Barbara +Mission, Calif., in order that the early settlers might kill off the +ground squirrels. A constant fight has been waged ever, since, but +unfortunately, while the landowners were willing to finance the killing +of squirrels on their own holdings, the Federal Government provided +inadequate funds to take care of the vast areas of public domain, +national forests, Indian reservations, and other Federal holdings. + + +Federal, State, and Local Cooperation + +When the Emergency Conservation Work Program came into being, +the Forest Service, the Bureau of Indian Affairs, the Bureau of +Reclamation, the Division of Grazing, and the Bureau of Biological +Survey took the opportunity to treat a vast acreage that would have +been treated years ago had funds permitted. During the three fiscal +years 1934 to 1936 a total of almost 20,000,000 acres had been covered +by E.C.W. for the control of these various rodent pests. On the statute +books of several Western States rodent-control laws provide that +landowners may establish rodent-control districts wherein all lands +are treated simultaneously by paid crews working under the supervision +of the Biological Survey. Never before the E.C.W. program were there +adequate Federal funds to make these laws effective by taking proper +care of infested public lands adjacent to private holdings. + +The most concrete proof of the necessity of rodent control is found +in the amount of money expended by private individuals throughout the +West for this purpose. The Federal Government, while owning as much +as 60 percent of the land in many of the Western States, contributes +only about 25 percent of the total cost of rodent-control operations. +During the fiscal year 1936, States, counties, and private individuals +expended $665,785 for the purpose, while the Biological Survey was able +to expend only $226,623 from regular appropriations. The E.C.W. program +afforded the first opportunity of somewhere near meeting the Federal +Government's obligations to the citizens of the West in the matter of +adequately controlling the rodent pests that breed and range on public +lands and from these strongholds infest and reinfest adjacent private +holdings. + + +Training of E.C.W. Crews + +Rodent control is one of the most popular projects with E.C.W. +enrollees themselves as well as with the local people benefited. In +many cases, crew foremen supplied by the Survey took boys who would not +work satisfactorily on any other type of project and made real hands of +them on rodent-control crews. The boys liked to work in these crews, as +it afforded them opportunity to become acquainted not only with methods +of rodent control but with the various habits of wildlife as well. + +In order to employ proper methods and place all possible safeguards +around poisoning operations for the protection of beneficial and +harmless species, the Biological Survey has insisted upon approving the +appointments of all men employed on the supervision of rodent-control +work for its various cooperating agencies. This is for the reason that +when poisoning campaigns are properly handled and carefully supervised, +there is little danger of the accidental poisoning of other animals. +The records indicate that there have been practically no cases of +destruction of other forms of life through the E.C.W. rodent-control +program. Naturally, the supervisors not only must know rodent control +but also must be acquainted with the habits and status of wildlife in +general, and in handling the crews they have imparted knowledge to the +beys that will be of permanent benefit to them and to the Nation. + +Educational programs were provided as regularly as possible, in +order to tell the C.C.C. enrollees of various wildlife problems. The +entire personnel of E.C.W. camps were shown films depicting the work +of beavers, showing measures for the protection of elk, deer, and +other big-game animals, and portraying the need of sane, sensible +conservation methods, in order that the remnants of our fast-vanishing +forms of valuable wildlife might be preserved. Mimeographed leaflets +on wildlife management studies were made up by district agents of +the Survey for the boys in order that they might be given as broad +instructions as possible in the protection and preservation of species +that are an asset rather than a liability to man's interest. It has +been the attempt of the Biological Survey to make the rodent-control +project a field laboratory for the education of the enrollees in +natural history and wildlife management, and the popularity of the +project among the boys attests to the wisdom of this course. In many +camps more applications for places on rodent-control crews were +received than there were places to fill. + + +Timeliness of Emergency Aid + +Fortunately, the E.C.W. program came at the most opportune time. The +extreme drought throughout the west had forced rodents from the open +lands into adjacent irrigated valleys and mountain meadows, where they +became especially objectionable in their competition with livestock +for the available forage. Livestock and rodents together, during dry +periods, have in many places almost entirely denuded the surface soil +of its vegetation. This has caused the beginning of sheet erosion in +areas where there would still be ample forage for livestock had it not +been for the excessive numbers of rodents. On many areas, grazing by +livestock and rodents combined has practically eliminated the native +grasses, and these are now being replaced with weeds and poisonous +plants. Damage in some instances has amounted to at least 75 percent +of the available forage, and the average loss has probably been +approximately 25 percent. + +On some of the Indian reservations of the Southwest, the condition has +been pitiful. On the Navajo Reservation, in particular, the Indians +have carried on a losing fight against drought and rodents. It has +often been necessary for them to replant their corn three and four +times a season, since kangaroo rats and other native rodents dig up the +kernels as rapidly as they are planted. Prior to the spring of 1936, +there had been four years of drought, and this, coupled with rodent +damage, had reduced corn production to the point where the Indians had +barely enough for the spring seeding. All were clamoring for aid, and +in order to save their last crop of corn it was necessary to detail a +foreman with four or five E.C.W. Indians to go from farm to farm and +conduct rodent-control operations. + + +Forest and Forage Protection + +The Forest Service is endeavoring to carry on a reforestation program +throughout much of the cut-over area in the Lake States and the Pacific +Northwest. One of the chief problems to successful reforestation +is the control of rodents, particularly the snowshoe hare. In the +Olympic Forest in Washington, the snowshoe hare has destroyed as much +as 40 percent and damaged 70 percent of the Douglas fir seedlings. +In Michigan and Wisconsin, it was necessary to carry on extensive +rodent-control operations to permit the seedlings to survive. Much of +this work would never have been possible but for E.C.W. help. + +In the open area, jack rabbits have become a serious pest. The +Biological Survey, in 1934, received a petition bearing the signatures +of more than 8,000 individuals of eastern Colorado, requesting +Government aid in killing jack rabbits, which were ravaging the meager +stocks of forage left after drought and wind had taken their toll. + +The Forest Service recognized that rodent control would be essential +if the Plains Shelterbelt program of planting trees from the Canadian +border to Texas was to be effective, and in 1935 approximately +one-tenth of its entire appropriation for the program was expended for +rodent control under the supervision of the Biological Survey. Crews +patrolled the planted areas constantly to prevent the gnawing of the +seedlings by jack rabbits and pocket gophers. + + +Aid in Erosion Control + +The permanent benefits accruing from the E.C.W. rodent-control program +have been enormous from the standpoint of erosion control alone. An +associate range examiner of the Forest Service has the following to say +regarding the effect of rodents on erosion in the Boise watershed of +Idaho: + + "Rodents, numerous and spreading over nearly 80 percent of the Boise + watershed, have undoubtedly been responsible for no small part of + the present erosion. Wholly dependent upon the herbaceous plants for + their food supply, their tremendous numbers, along with over-grazing + by livestock and unfavorable climate, have been an important + contributing factor in depleting this cover, and thus have greatly + reduced the protection afforded the soil and subjected it the more to + increased sheet erosion. Even light rains on rodent-infested areas + are likely to start cutting, which may develop into destructive gully + erosion because of the almost immediate accumulation of run-offs in + the myriads of burrows and channels which these animals construct + just under the surface of the soil." + +The control of rodents is vital to the successful operation of +reclamation projects in the western third of the United States. +Rodents, particularly pocket gophers, find the banks of irrigation +canals an ideal location for their burrows and runways. These +subterranean passageways frequently are the cause of serious breaks +in canals, through which the flow of irrigation water is diverted +and wasted to flood adjacent lands, destroying valuable crops, and +indirectly ruining others by causing delays in delivery of water. +Through the E.C.W. program, C.C.C. crews working under the direction +of experienced foremen trained by the Biological Survey have greatly +reduced this menace. In the past year alone half a million acres of +canal banks and contiguous lands were treated by C.C.C. rodent-control +crews with a thoroughness that will be of lasting benefit to the +nation's reclamation projects. + + +Examples of Benefits Derived + +A few concrete examples will illustrate the great good that has +resulted from the E.C.W. rodent-control program. A group of farmers +living at Springfield, Idaho, suggested to the camp superintendent +there that the jack rabbit control work done by the E.C.W. crew during +the summer of 1935 might pay the cost of the camp. It is estimated that +not less than 600,000 rabbits were killed by this crew on public lands +adjacent to farming areas between American Falls and Moreland, Idaho. +The work afforded protection to not less than half a million dollars +worth of cultivated crops and to more than 75,000 acres of grazing +lands. + +The control work carried on by an E.C.W. crew near Weber Lake, Calif., +in 1933 has been responsible for a 50 percent comeback of the grass +on a large mountain meadow, which had been made a dust heap because +of pocket gopher workings. The pocket gophers had honeycombed the +surface of the ground, and sheep had trampled out most of the grass, +while livestock grazing had been reduced to a negligible figure. The +restoration in two years was due primarily to the elimination of the +pocket gophers. + +To control prairie dogs in Oklahoma, an area, of 47,000 acres in +Pawnee, Noble, and Kay Counties was treated through the medium of the +E.C.W. The Indian lands here are interspersed with private lands, and +the landowners were unable to make any progress in a general clean up +because there were insufficient Federal funds to treat the Indian lands +until the E.C.W. project afforded opportunity to carry on a systematic +campaign over the entire area. A good piece of work was accomplished, +and this, in conjunction with water developments, made the grass so +much better over these old prairie dog towns in the spring of 1935 that +the Indian Service officials at Pawnee received an increased rental of +25 cents an acre on their grazing lands. On areas where they received +50 cents an acre in 1934, they received 75 cents in 1935, a direct +increase in receipts to the Federal Treasury. + +The permanent benefit accruing to the Indians from E.C.W. rodent +control is summed up as follows by an Agricultural Extension agent of +the Indian Service, at Anadarko, Oklahoma: + + "No little stress can be placed upon the financial value of the + rodent-control project to the Indians. The Indian enrollees received + the labor benefit on both Indian and deeded land throughout the + reservation but still greater than the temporary labor relief, the + Indian has received a lasting increase in the financial rental of his + land. Due to such heavy prairie dog infestation of the allotted land + it had become necessary to reduce the rental value of the grass land + infested. Now that the prairie dogs have been controlled the rental + value will be increased by approximately 10 cents or more per acre + because the pastures will regrass and the carrying capacity will be + increased. In comparing this increase in rental value with the cost + of controlling the prairie dogs, the Indians will reap the financial + benefit of the Government expenditures in two or three years. + Therefore, this project has certainly been of utmost value to the + reservation and the Extension Division in helping the Indian to help + himself." + + +Safeguarding Harmless Species + +Some persons uninformed as to the need for rodent control and the +methods followed by the Biological Survey in carrying on the work have +stated that control by use of poison and C.C.C. workers endangers the +existence of other forms of wildlife. This, however, is not the case. +The Biological Survey has studied rodent-control methods for more than +twenty years and in this period it has developed the most scientific +and selective poisons possible. Scientific investigations conducted +by the Bureau are bringing increasing knowledge of the habits of +economically injurious species and of their physiological reaction to +various baits. This has made it possible to use more and more specific +control methods and so to select, prepare, and expose poison baits as +not seriously to endanger animals other than those for which the baits +are intended. When these scientific methods are carried out under +direct supervision of trained personnel, the total number of beneficial +species destroyed is negligible. + +The Biological Survey is a conservation organization and will undertake +no work that will be detrimental to any species of animal not +interfering too greatly with the interests of man. Those conversant +with actual conditions in the range States realize that if agriculture +is to survive, the control of injurious rodents is as essential as +is control of the corn borer, the chinch bug, the boll weevil, the +grasshopper, the coddling moth, and numerous other agricultural +pests. The Survey insists that in conducting work of this sort, the +most careful supervision by trained technicians must be given. All +cooperating agencies recognize the necessity for such supervision, and +as a result a most worth-while program has been carried on during the +past three fiscal years. The Biological Survey has entered into written +cooperative understandings with the various governmental agencies under +which rodent-control activities have been conducted. These agreements +place the responsibility for technically supervising all rodent-control +activities in the hands of the Bureau, leaving the cooperating agencies +responsible for administration. + + +Control Work Illustrated + +The illustrations on the following pages tell better than would volumes +of written words, the story of rodent damage and of cooperative work to +reduce this damage. + +PRAIRIE DOGS + +Four years experimental study in northern Arizona showed that prairie +dogs destroy 60 percent of the wheat grass, 99 percent of the dropseed, +and 83 percent of the grama grass, or 80 percent of the total potential +annual production of forage. The possible destruction of four-fifths of +the forage, or even a far smaller proportion, is serious enough at any +time, but in periods of drought it is likely to be calamitous. + +The following pictures show typical prairie dog infestation. + +[Illustration] + +Prairie dog mounds on abandoned Indian farm, Southern Navajo +Reservation, Arizona. + +[Illustration] + +Area practically denuded of grass by prairie dog--Wescalero Indian +Reservation, New Mexico. + +[Illustration] + +Dogs on leash and tin cans rattling in the wind are some of the +primitive methods employed by Indians in futile attempt to save crops +from ravages of prairie dogs in the Southwest. + +[Illustration] + +[Illustration] + +Indian cornfield totally destroyed by prairie dogs. + +[Illustration] + +Cotton and corn fields damaged by prairie dogs in northwest Texas. + +[Illustration] + +[Illustration] + +Side of basin denuded by prairie dogs--devastation being rapidly +completed by erosion. Cochetopa Forest, Colorado. + +[Illustration] + +Prairie dogs prepare an ideal condition for the start of sheet +erosion on hillsides by denudation of vegetative cover. Note lack of +vegetation. Erosion once started is accelerated by other factors as +shown on page 11. + +[Illustration] + +[Illustration] + +Overgrazing, wind, and flood-- + +[Illustration] + +resulting in gullies and arroyos. + +[Illustration] + +[Illustration: Interpreter explaining to Indian farmer in Arizona how +to expose poisoned grain. The Indian, at the left, stated that he +picked up 180 dead prairie dogs over an area estimated at about 200 +acres around his 48 acre farm.] + +GROUND SQUIRRELS + +[Illustration: Ground squirrel damage. Semidesert type country. Note +squirrel at mouth of burrow.] + +[Illustration: E.C.W. ground squirrel control crew--Payette National +Forest, Idaho.] + +[Illustration: E.C.W. crew at work on Umatilla National Forest, +Washington.] + +[Illustration] + +Ground squirrel burrows become waterways during a rain and are the +beginning of this type of erosion. + +[Illustration] + +Papago Indian Reservation, Arizona. + +POCKET GOPHERS + +[Illustration: Typical mountain range land, heavily infested with +pocket gophers--Davis Lake, Oregon--before treatment.] + +[Illustration: Same area one year later after pocket gophers were +brought under control and native grasses had had a chance to reseed.] + +[Illustration: Farm land infestation--Texas. Mounds represent pocket +gopher workings.] + +[Illustration: Mountain meadow in Utah. Picture taken just after snow +had melted in spring. Ridges of dirt show extent of pocket gopher +operations under snow in winter.] + +[Illustration: Pocket gopher infestation--Louisiana.] + +[Illustration: Break in terrace caused by pocket gophers burrowing +through embankment.] + +[Illustration: Pocket gopher infestation along highway.] + +[Illustration: Flood water starting through a pocket gopher burrow +passed under a cement highway,--] + +[Illustration: Flooded the barrow pit on the opposite side of road, and +poured into farmer's field, leaving a deep wash as a monument.] + +[Illustration: Damage starting from pocket gopher hole in irrigation +canal bank--] + + +[Illustration: Soon results in bad breaks causing expensive repairs and +loss to crops through failure of irrigation water.--] + +[Illustration: And is often responsible for start of gullies.] + +KANGAROO RATS + +Kangaroo rats abound on millions of acres of desert and semidesert +range and farm lands. On ranges that have been overgrazed, kangaroo +rats must be controlled before reseeding can be accomplished, as they +gather and store practically all of the seed within a radius of 100 +yards from their burrows. + +[Illustration: Close-up of typical kangaroo rat den.] + +[Illustration: Showing plot protected from both livestock and kangaroo +rats.] + +[Illustration: Plot showing grazing by kangaroo rats--livestock being +excluded.] + +[Illustration: Area on left of fence subject to grazing by both +livestock and kangaroo rats. On right of fence shows protection from +both livestock and rodents.] + +[Illustration: Open range--note lack of native grasses.] + +[Illustration: Kangaroo rat den around mesquite bush. Note lack of +vegetation.] + +[Illustration: Typical kangaroo rat infestation.] + +[Illustration: Trail leading from kangaroo rat den to feeding ground.] + +[Illustration: Close-up of feeding ground. Note rat pellets and close +cropped grass.] + +[Illustration: Kangaroo rat den before excavating,] + +[Illustration: Cross section of den, showing storage chambers and +stored grass seeds.] + +[Illustration: Seed heads taken from one kangaroo rat den-- + + A--Burrow grass seed. + B--Indian wheat heads. + C--Weed seeds. + D--Unidentified grass heads.] + +[Illustration: Kangaroo rat den before treatment (July 1, 1935), Papago +Indian Reservation, Sells, Arizona.] + +[Illustration: Same location as above two months later after +eliminating the kangaroo rats.] + +RABBITS AND HARES + +Reforestation is greatly hampered by rabbits in cut-over areas where +intermittent fires have killed all seedlings over a period of years. In +many areas the snowshoe hare will eat off as many as 40 percent of the +seedlings and damage up to 70 percent of them. + +[Illustration: Rabbit-infested reforestation area--Olympic National +Forest, Washington.] + +[Illustration: Damage to jackpine caused by snowshoe hares--Dukes, +Michigan.] + +[Illustration: Healthy Norway pine. Snowshoe hare damage to pine and +spruce seedlings at this stage of growth consists of nipping the +terminal bud.] + +[Illustration: Spruce tree with lateral branches removed by snowshoe +hares--Price County, Wisconsin.] + +[Illustration: Typical damage to cornfield by jack rabbits--Texas.] + +PORCUPINES + +On many national forest areas the control of porcupines is imperative +from the standpoint of timber reproduction. This is especially true on +cut-over areas and where fires have destroyed all seedlings. Porcupines +will often destroy up to 90 percent of the seedlings and, through +continued girdling of young trees 15 to 25 years of age, will destroy +all chance for commercial timber for many years to come. + +[Illustration: Typical porcupine den. Picture taken on Pike National +Forest in Colorado, in area where porcupine control work was conducted +under the Forest Service E.C.W. program.] + +[Illustration: Porcupine at work girdling pine tree.] + +[Illustration: Showing one of 114 young pines damaged by porcupines on +15 acres.] + +[Illustration: Additional evidence on cut-over areas.] + +[Illustration: Porcupine at foot of tree probably 15 years old, which +it has damaged beyond hope of recovery.] + +[Illustration: Complete girdling by porcupines about 12 inches above +ground.] + +A TYPICAL E.C.W. CREW + +[Illustration: E.C.W. crews have treated almost 12,000,000 acres +of rodent-infested lands during the past three years, have done it +carefully and well, and in so doing have been taught valuable lessons +in wildlife management.] + + + * * * * * + + +Transcriber's Note + + +Original publication appears to have been a copy of a typewritten +document. + + + + + + +End of the Project Gutenberg EBook of Wildlife Research and Management +Leaflet BS-54: Rodent Control Aided by Emergency Conservation Work, by Stanley P. Young + +*** END OF THE PROJECT GUTENBERG EBOOK 59318 *** |