https://cpw.cvlcollections.org/files/original/31bd756423574c93303dc06d6cb576f9.pdf 25bc3941cb6df76e736063cc24a1d98c PDF Text Text TO: ALL FIELD PERSONNEL Over the past year you have been receiving Fisherie s Leaflets to help acquaint you with some of the problems and methods used in fishery activity. This l etter will initiate the issuance of similar l eaflets to cover the field of Game Management and Game Research. These leaflets will be coucerned with a variety of game management and federal aid s ubjects, which will be labled for your conve,1ience. The first series of leaflets will deal with the huilting of some of Colorado's game ani mals . The purpose is to help field men answer questions put to them by the public on the best hunting methods for various ga me . These article s a re the opinions of the writers - aot the final word. You may have some ideas and innovations of your own to add. It is hoped that these 1,-illets will be fotere sting and informative , and that they will be some measure of help to the man in the field in his daily work. BUD FLINN Dist. I & E Manager Approved by: F erd Kleinschnitz, Asst. F ed Aid Coordinator C. D. Tolman, I & E Manager �Subject: Filing System SPECIAL LEAFLET Recently there has been some indication from the field men for a simplified and easy-to-use filing system. It seems that a host of material is continuously being received, piling up, and getting lost in the shuffle. When time comes to find a particular piece of information a general search is under way. Devising a simple filing system is not easy, especially when every individual has his own ideas and his own needs. A system for one will not satisfy another. And any suggested filing system will be just another idea by another individual. But - let's start by suggesting some of the major headings that wildlife workers may have need for, and then point out some of the sub-headings that may be added. This system may be further simplified, if desired, or changed and complicated, according to your particular wishes and needs. ADMINISTRATION: Automobile and equipment records. Department correspondence and reports. Federal Aid Division. Law Enforcement. Information - Education In-service Training (Game & Fish Leaflets - Schools) Inventory - (Supplies, Withdrawals, Receiving Reports, Requisitions) Management Areas - (Refuges) Maps Newsletters Personnel Records (Annual Leave, Merit Ratings, Civil Service) Big Game Check Stations Habitat & Habitat Development Seasons & Regulations _____Tipland Game Check f tations Haliitat & Habitat Developments Seasons & Regulations Antelope Bear Bighorn Deer Cottontail Doves Grouse Partridge Pheasants Quail Squirrel Wild Turkey Elk Others �Page 2. ( Special Leaflet - on Filing System ) Fur Resources Waterfowl Seasons and Regulations Check Statio¥ Habitat and Habitat Development (Water, Reservoirs, etc.) Seasons and Regulations Badger Fox Marten Mink Muskrat (If you want to elaborate further I sub-headings under each of the species listed above might include: Range and Distribution; Food habits; Disease: Damage and Control: Trapping and Transplanting; Census Methods: Annual Kill Statistics, etc.) Fish Food Habits Habitat Development Hatchery Operation Salvage Seasons & Regulations stocking (ETC.) Species - Bass, Brook, Brown, Crappie, Drum, Etc. A final heading of major importance (and probably the most used) might appropriately be labeled "MISCELLANEOUS". In this group you-may include such subjects as: Aircraft; Birds,- non-game; Colorado Wildlife Federation; Bureau of Land Management; Rough Fish; Fish & Wildlife Service; Legislation; Mammals, non-game; Soil Conservation Service; and anything else that you don't lmow what to do with. It may be wise to start with the major headings and those sub-headings which you lmow you need now - then fill in the other sub-headings as they are needed. (2) �GAME INFORMATION LEAFLETS 1. 2. 3. 4. 10/1/56 10/15/56 11/1/56 11/15/56 12/1/56 12/15/56 1/15/57 4/15/57 5/1/57 7/15/57 9/1/57 9/1/57 12. 12/1/57 12-B. :~1/15/58 13. 7/1/58 14. 3/15/59 15. 4/15/59 16. 6/15/59 17. 10/30/Jj 5. 6. 7. 8. 9. 10. 11. ~ S'i Methods of Hunting Pheasants, Wayne W. Sandfort. Care of Big Game Hides, Wild Turkey Hunting Techniques, By Martin Burgett. "Productivity Rates, Age Classes, and Sex Ratios of Spring-caught Beavers in Colorado, By Wm. H. Rutherford. Artificial Revegetation on Big Game Winter Ranges, Claude E. White, Jr. Some effects of heavy use on Browse Plants, Harold R. Shepherd. Some Sex Determinants of Game Animal Carcasses, Richard N. Denney Warbles of Cottontail Rabbits, R. E. Fillmore. Lungworms in Colorado, R. E. Pillmore Winter Food Plots as an Aid In Wild Turkey Management,Donald M. Hoffman. The Use of Baled Oat Hay In Winter Feeding of Wild Turkey.By C.Scott Aging Pheasant Embryos, By Wayne W. Sandfort. Origin of Bighorn Lungworms, By R. E. Pillmore Lungworm in Bighorn Sheep, By R. E. Pilmore Buffalo Peaks Bighorn Seasons, by R. E. Pillmore. Rabies and Wildlife, By R. E. Pillmore Lungworm and Lambs. Pheasant-Insecticide Study Report. New Possession Limit on Pheasants Explained, By H. Swope. �Ganje Leaflet No. I October 1, 1956 subject: HUNTING METHODS OF HUNTING PHEASANTS By: 'Wayne W. Sandfort 1iil~liiillrn~~ BDOW026616 Methods of hunting pheasants vary almost as much as personalities of pheasant hunters. No one can say which method is most effective, for weather, character of cover and terrain, and other factors cause wide variation in pheasant behavior. A few basic procedures, however, should aid in placing rrJore birds in the game bag. Prior to opening of the season, much can be done to increase chances for success later on. Activities may include: (1) checld;:1g 011 bird populations and selecting a general area within which to hunt, followed by obtaining permission to hunt on specific farms and in specific fields, (2) shooting practice with trap, doves, or other moving targets, (3) training a retriever or bird dog, and (4) taking a self-imposed course in pheasant sex identification. With opening of the season, punctuality, or "being there" at starting time is important. Getting first chance at "uneducated" pheasants in areas of most de-sirable cover (usually corn fields on irrigated lands, and cover plantings or weed patches in dry-farmed areas) contributes much to initial success. Following the first few hours of the season, pheasants are dispersed and wary. They may be found almost anywhere, from isolated Russion thistles to heavy, creek-bottom cover. Cattails (after snowstorms) and cornfields (in late afternoons), however, are good bets for birds. In addition to being in the right place at the right time, the following maneuvers or techniques should aid pheasant hunters: Block and Drive: .... Stationing hunters at the ends of cornfields, weed patches, fencerows, irrigation ditches, draws, or other cover, to intercept birds which run ahvad of "drivers, " is advisable in practically all instances. Round-up: ... TrJs method depends upon assembling a sufficient number of hunters to encircle large fields. It is probably the only method by which pheasants can be effectively harvested in open wheatlands in eastern Colorado. All hunters should move slowly forward, driving birds toward the center of the circle. Caution must be exercised when shooting. ~!s and Wait: ....This technique is useful for persons hunting £lone, as well as for those hunting in groups. The hunter walks slowly for a short distance, then stops and waits. The period of waiting should be long enough ( 30 seconds or more) to surpass that of a rooster, which may be excitedly hiding nearby. Use of Dog: ... 8 good dog, moving ahead of the hunter to find or flush birds and to retrieve cripples, is a· decided asset. Road-hunting:.... One of the most popular, and least desirable, types of pheasant hunting consists of driving, looking, finding the cock pheasant, and "pot--shooting." If road-hunting is employed, the following approach is suggested: find the bird; see where it goes; get permission to hunt; go after the pheasant on foot. This improved road-hunting technique may result in fewer birds, but will be legal and should save farmer friendship. �GAME LEAFLET NO. 2 Date: October 15, 1956 CARE OF BIG GA_~ HIDES One of the basic obligations of the Game and Fish Department is to offer information and service to Colorado's sportsmen wherever it is practical. There are many ways this can be done. One small way we might go toward this objective is by helping to preve~1t undue waste of the game. •Department personnel should take every opportu11ity to spread information on the care a11d use of the game taken by sportsmen. It is a known fact that a great many hunters do not make full use of the game they kill. Often useable meat is left to waste in the field, meat is lost, or it spoils due to ~.ieglect or from not knowing how to take care of it. A small folder, "Handling Your Big Game Kill" is being distributed to sportsmen this year to help preve:.1t meat losses. The hides of our big game animals are valuable and useful too, but many hides are destroyed and discarded because hQ::ters do not realize their value, and do not k1lOW how to handle and preserve the skins. Here is a list of simple steps for preserving hides w1til they ca,1 be brought ia for tannbg. Ski.ls may be preserved by three methods: Drving -- Refrip;eration - Saltini;. Salting is the easiest, most convenient, and safest way. Salt is cheap and you need very little. In skinniag, avoid cutting the skin. Remove as much of the fat as possible so that the salt can penetrate the skin. Lay hide out flat aad rub salt into flesh side, payL.1g particular attention to the corners and edges. Fold edges in and roll into bundle. If skins are to be shipped, tag and bundle so that it can be identified; wrap in waxed paper, then cover with burlap or place ii.1 a box. For best results, bring skin in for tam.iii.lg as soon as possible. Be sure to attach tanning instructions and specify color skins are to be tanned. (There are five colors: pearl gray, cream, suntan, chocolate brown, and black.) Do not allow hides to dry in folded or rolled condition as it will result in cracked grain. If it should be necessary to keep skins for any length of time, stretch or tack salted skins indoors or in shade so that they will net dry wrinkled or crumpled. (The sun will parch or grease-burn skia.) Skias that have been refrigerated deteriorate more rapidly than those left under normal temperatures. Skins should always be salted after taking out of refrigeration. ~ One average size deer hide will produce three or four pairs of gloves. Itwill take three to four deer hides to make a buck skin jacket. A jacket made of elk hide will require one and a half to two average size elk skins. 1liiiliilm~~ BDOW026617 �GAME LEAFLET NO. 3 Date: November 1, 1956 Subject: _ _H_un_t_in_.g_ __ VJILD TURKEY HUNTING TECHNIQUES By: Martin Burgett The. first step a hunter for wild turkeys should take is to locate an area where turkeys are ranging. Since turkeys are creatures of habit, they follow well-defined patterns of feeding and watering that can be used by hunters. They normally leave their roost at gray dawn, and feeding is their first activity of the day. Since the digestive processes have continued while roosting, they are hungry ;in the morning. Turkeys will feed from one-half hour to two hours in the mornings, depending on the abundance of food available. Most of {~c.:lr food at this time of year is rather dry, consisting of grain, dried berries and fruits, and grass seeds. It takes considerable water to di-gest these dry fQods so they naturally go to water from the feeding area. After the watering period there is a loafing time. On warm days they will loaf in the shade. On cold days they spend this time in the open sun. Wild turkey hunting methods come under two main headings: Still hunting, and Cross-country hunting. V. Still hunting may be done in several .ways. The hunter can conceal himself near a feeding area or watering place and let the turkeys come within shooting range. Often the turkeys location is revealed by the call of the birds. Usually a mature hen calls the flock to a feeding area or watering place. Then the poults or older birds answer. In this way the location of the birds is quite simple. Once this calling is heard the hunter may use a turkey call (there are many types) to lead the birds within shooting range. If the call is not properly used it will drive the turkeys away instead of bringing them to the hunter. It takes a little practice to talk "turkey talik.. " The Cross-countri hunting method probably is the most sporting method of hunting turkeys. Within a known ranging area the hunter stalks or walks through turkey range until he contacts and flushes a flock of turkeys. Turkeys are not easy to approach either in open or timbered range. If the hunter is not careful in his approach he will flush the turkeys ahead of him without seeing or hearing them. By observing closely it may be noted that the places where turkeys have re~ently fed will be damp. The leaves or needles will be freshly raked, and the ground wet underneath. This indicates the turkeys have fed in the area within the last few minutes. The hunter can even find the direction the birds are moving by this sign. From there the approach to any rising ground should be with caution, When the birds are seen the hunter should walk toward the flock rapidly, causing the birds to fly. Then sit down and remain quiet until the turkeys begin calling to get back together. Then the hunter can use a call, and call the birds back within shooting range. One caution should be observed - the hunter should remain very still until he is ready to shoot. 1Nhen turkeys are getting together they are very cautious. A movement of the hand or a shift in position would cause the turkeys to fly. Any movement at such times should be very slow and deliberate. 1illmf1ffllDlll1 BDOW026618 fffl:f ###II= �November 15, 1956 Game Leaflet No. 4 "PRODUCTIVITY RATES, AGE CLASSES, .AND SEX RATIOS OF SPRING-CAUGHT, BEAVERS IN COLORADO. By: Wm. H. Rutherford Since the spring of 1954, Project W-83-R personnel has examined a total of 394 female beavers taken during spring trapping in northern and north eastern Colorado at elevations both above and below 5000 feet. Compilation and analysis of the records from these examinations have revealed several points of interest from the standpoint of beaver management. Of the total of ·394 females 281 were taken at altitudes above 5000 ft. and 113 below 5000 ft. A total of 129 were either pregnant or post-partum (young. already born). The pregnancy rate for _the ~ntire sample, therefore, was 33o/o. On an altitude basis the pregnancy rate above 5000 ft. was 31 % while below 5000 ft. it was 3 7%. Among mature females the pregnancy rate was 75% for both altitudinal zones. The comparison of these pregnancy rates shows that a greater proportion of the females taken below 5000 ft. were mature. The average number of young· per litter (based on embryo counts from pregnant females and placer.ta!-. scar counts from post-partum females) was 2. 7 above 5000 ft. and 4. 4 below 5000 ft. The average riumber of young per litter has remained constant or nearly so during the three spring seasons for which data have been recorded. The pregnancy rate has fluctuated from year to year during this same period. This fluctuation is believed to be due to the chances inherent in trapping, rather than to actual year-to-year differences in pregnancy rates. It has been demonstrated on several occasions that trapping does not give a true random sample of the population. This is especially true in regard to difference-s in trap susceptibility among various age classes. It is well known that two·-year-old beavers do a great deal of moving in the spring. This gives them greater opportunity to visit trap sets, and this susceptibility is reflected in the age class figures. Roughly twice as man~ two year olds as one year olds were caught. Obviously, this is a biased population sample, ~ince there cannot at all times be twice as many two year olds as one year olds in any animal population . .Also, two year olds and mature beavers made up approximately the same proportion of the catch, which again is an untrue picture of the population. The age class figures are useful only as year-to-year trends, and are not useful as actual population figures. Bias is also exhibited in the sex ratios of the trapped beavers, but is not as easily explained. Below 5000 ft. the sex ratio was 86 males : 100 females; while above 5000 ft. the ratio was 77 males : 100 females. There is no reason to believe that females are more· susceptible to traps than are males; on the other hand there is no reason to believe that there are always more females than males in a beaver population. Until a much larger sample is available for analysis, a sex ratio of 100: 100 will be assumed in making management recommendations. ...._,.... On this basis the calculated average annual population increase was 42% above 5000 ft., and 81% below 5000 ft. Since these rates of increase are derived from embryo and placental scar counts, the figures do not include calculation of juvenile mortality. ###### 1li■llllli~~ BDOW026619 �- GAME LEAFLET NO. 5 ' December 1, 1956 ARTIFICIAL REVEGETATION ON·aIG GAME WINTER RANGES __By_:_Cla':!fl_!_!:_~1hite, «!f • _____________ _ Lilt~ most of the other western states, the Colorado Game ~d !'!sh Department is faced with an increasingly important winter ·range problem with respecfto our wintering deer herds. The destructive use of vegetation. plus the resulting loss of the vital top soil has depleted some of our winter ran~s -to ~he p<;>int where it would take many years to bring back the range to its original carrying capacity with protection alone. Since in most cases it is impossible to give the range the prot~ction that would be needed to bring back the range naturally, it was felt that the field of ~rtificial revegetation should be thoroughly explored in order to determine if such . measures would be economically feasible. For the past four years the Department has carried on research programs designed to find the most efficient and economical methods of artificial revegetation depleted winter ranges. Our goal was to find methods that would, (1) halt as much gully and sheet eroslon as possible. The methods used must provide, (2) a maximum use of the available precipitation. Since it is impossible to provide a browse density equivalent to the original stand; .the methods must, (3) provide better growing conditions for the present browse stand and ~crease its annual production of forage. (4) Tho methods used should be -progressively efficient in the production of forage for deer and should last at least ten years without benefit of retreatment. .(5) Range management with respect to both deer and livestock should proceed in conjunctioo -with the range treatment. (6) The methods used must be economically feasible. Other plants, preferably legumes and bunchgrasses should be planted in between the· contours to hasten the build-up of litter and humus in the soil. So far the research progranFhas succeeded in developing an efficient method of soil preparation, selecting several species of browse for planting on the contours, and several species of grasses and legumes for plan ting in between the contours. The method of soil preparation selected is intensive contour furrowing at intervals of 8-12 ft. The contours are interrupted alternately at intervals of approximately 50 yds. Two passes are required on·each·contour in order to provide enough soil to plant seedlings on and to secure the proper·-.c-ontour width and depth. The work is done with a motor patrol equipped with a level bubble that eliminates the necessity of staking out the contours ahead of time. The browse species selected to date include 4-wing salt bush, squaw bush, silverberry, and Russian olive.. Of the four, only 4-wing salt bush is grown in the field from seed, the rest are planted in the form of one year old seedlings. The work ~n._-suitable species is continuing. 1iiiiiilifoo BDOW026620 �Page 2. Artificial revegetation on big game winter ranges. By: Claude E. White, Jr. An analysis of the field plantings at Gunnison shows that it is possible for the Colorado Game and Fish Department to materially increase the forage available for deer with the climate and soil types that exist in the Gunnison area. The cost for the complete treatment has now been set at $l5 - $20 per acre. As to whether or not this is considered economically feasible requires that we place a value on each herd of deer 11rthe state~ The methods that have been developed are progressive and within limits, will provide an increasing amount of available forage over a period of time. No rotre::itment will be required. The cost quoted is considerably less than the cost of similar work that has been completed in Utah and other states. The work at Gunnison is proceeding in coordination with the Colorado Pilot Area program - an interagency program de signed to coordinate the range development activities of the state and federal agencies in the area. The adjustment of both livestock and deer use in the area is proceeding in conjunction with the Pilot Area program. �Subject: Range Management GAME L_EA FLET NO. _L December 15, 1956 SOME EFFECTS.OF HEAVY USE ON BROWSE PLANTS By: Harold R. Shepherd "How much punishment can a browse plant stand?" is a question that everyone who has worked with range problems has .often asked himself when looking at a severely used range. The Mesa Verde Clip Plot Study, being conducted by the Federal Aid Division of the Colorado Game and Fish Department, is an attempt to learn the answer. The study has not yet provided the complete answer, but it has demonstrated several facts about the way sagebrush, bitterbrush, serviceberry, oakbrush, and mountain mahogany react to browsing that are important to the range manager: 1. If only the current-growth stems (stems of the year) are removed, most plants of those kinds mentioned can: survive the annual removal of all of the currentgrowth stems for a period of four or five years. However,. the removal of old wood, in addition to the current growth, is very harmful and results in the early death of many plants. • 2. The plants in the study, listed in order of their ability to withstand destructive browsing, from hardiest to least hardy are as follows: oakbrush, serviceberry, mountain mahogany, bitterbrush, and sagebrush. 3. Oakbrush withstands destructive use best, and sagebrush is the least hardy. For example, the removal of two year's stem growth in one year, and all of the stems to a diameter of 4 mm. the second year killed none of the oakbrush plants . In contrast, the removal of two year's stem growth from sagebrush killed 80. 2 per cent of the plants the first year, and after the current growth was removed the second year, all of the plants died. This vulnerability of sagebrush to the removal of more than the current growth is probably due to its inability to produce stems from old wood. 4. Bitterbrush is nearly as vulnerable to the removal of more than the current stem growth as is sagebrush. For example, the clipping of two· year's growth one year, and of all stems to a diameter of 3 mm, the second year killed 72. 5 per cent of the plants. 5.. A typical reaction of plants to destructive use is the production of fewer but longer stems and fewer but larger leaves. Another is a large increase in the nµmber of sucker stems around the base of all plants tested, except sagebrush. It seems likely to the author that sagebrush (and other plants to a lesser extent) on heavily-used ranges are killed out a stem or a branch at a time by foraging domestic or game animals that eat- more than the current growth. Often in heavily-used winter range areas, especially during severe winters, big game animals eat more than the current-stem growth. The author remembers one winter when deer and elk were reduced to eating old, woody stems of mountain mahogany and oakbrush as large as one half inch in diameter. Even during normal winters on· overstocked ranges game will often eat more than the current growth from many stems. Most permanent injury to browse plants probably results when current-growth stems become so short that bites often include old wood. ,irmoo~imnmn,,~~ BDOW026621 �Game Leaflet No. January 15, 1957 7 --- S.QME SEX DE_!!:RM~TANTS OF GAME ANIMAL CARCASSES _By: Richar.21:_T. Der.x.ey In January, 1952 a letter was sent out to all field men with some attached sltetches and expl&na·~ions of certain basic anatomy characteristics which were u.3e_d to determine sex in beef carcasses. Sir"oe that time some of these have been applied extensi·,ely on game animal carcasses, and with smn'3 modifications and variations, and recognizing ce:i:"t~L"'l shor~comings, it is felt that they are a valuable aid to law enforcement of sex in "antlered only" hunting areas. The principal criteria of sex that can be used ~n our bj.g game carcasses is the pizzle eye, or pe1:1.ile ligament insertion, which appears as a white, heavy-walled duct. These drawings a:a...e made simply so that these particular details stand out, but they are generally easy to ol>serve on the actual carcass. The ability to distinr,-.1:iah the pizzle eye depends quite a bit cu how oleanly or nearly c~ntered the cutti~,g of the pelvis or hind.:iuarters was made. Also: the time that the meat has hung in a hu:iting camp has a direct bez.rfng on the ease of locating the pizzle eye, as the gracilis muscle tends to dry and shrink away from the aitch bone after a short period of time when not refrigerated. Even so, by cutting into the meat immediately posterior to the aitch bone, gristle or· other cartilaginous remnants of the pizzle eye may be located. The lobulated-appearing cod fat on the bucks and· bulls has been fairly obvious and constant when checked at the Rifle check station to augment other sex determinants if the hunter hasn't stripped a lot of the tallow from the carcass. Some of the other factors will be less evident on game animals, such as deer and elk, due principally to the fact that they do not lay on the covering of fat that beef animals do. Therefore, perhaps the bracilis muscles and bald spot may not be as modified in shape, or may be less readily discernible, between the sexes, as presented in the sketches. It was believed at the time that the original letter was written that the curvature of the aitch bone was too relative a factor to be con sidered seriously, but subsequent spot checking at the Rifle check station on elk has revealed that further investigation is warranted as this factor showed up fairly constantly and was easy to discern. A more definite technique for determination of sex will be presented in a forthcoming paper involving the measurement of the pelvic span which, supplemented with the pizzle eye and other sex determinants, will give us positive sex determination on dressed and/or quartered carcasses of deer, elk, antelope, bighorns, etc. • Definitions of the terms used and their locations on a beef carcass are presented on the attached sketches. 1iU~irli]lilOO~ BDOW026622 �Beef (Male) Hindquarter Pizzle eye cap or Bald spot pizzle eye Aitch bone Gracilis IID.lscle �~ Determination (~) Definitions Aitch bone-that portion of the pubic arch exposed as a result of splitting the pelvis through the symphysia pubis; or, in other words, it is actuall,y the split pelvis. LocatErl on the inner side or a hind quarter of beet; slightly 11 s11 shaped in steers and heifers.. It is directly posterior to the aitch bone that the pizzle eye's presence is noted in carcasses from males. Fizzle !l,!.--the remains of the crural attachments of the penis, or, insertion of the penile ligament, located at the posterior end ot the aitch bone. Fizzle !l.!, cap o r ~ ~ - t h e exposed red muscle located adjacent to the point of the aitch bone, and surrounding the pizzle eye. Usually round or oval in shape and somewhat larger than a silver dollar. Only found in male 9arcasses. ~ f!i--the fat which accumulates in the region of the scrotwn or in the scrotal sac of males. Gracilis muscle--exposed muscle just above the aitch bone, bean shaped in females, but dips to the aitch bone in nales. Sex Determination (Beef) Constant factors ....•... l. 2. .3. Relative factors .•...•.• 4. 5. 6. 7. 8. Fizzle eye. Fizzle eye cap or bald spot. Cod (rough, lobulated) or udder fat (smooth) Shape. of the gracilis muscle. Shape of aitch bone (more curved in males). Internal surface of ribs (rounded on males). Neck and shanks (heavy and masculine - males) General conformation (females finer boned, ' lack the prominent round). �Game Leaflet No. __ L April 15, 1957 WARBLES OF COTTONTAIL RABBITS By: R. E. Pillmore The cottontail, our nation's number one game animal, is highly esteemed boti'l for the sport it offers and for the table. In dressing the rabbit for the table, one or more larr,e grubs may occasionally be found by the hunter under the skin of the rabbit. When this happens, the ral:>bit is usually rer,arded as "wormy''. It does not matter whether or not the food value or flavor of the flesh has been harmed, the "worm" has has offended the hunter esthetically and the rabbit will 'f?e thi·cwn away. However, if the grub manages to leave unobserved, either just after or before the rabbit was killed, •the enjoyment of fried rabbit on the pa'rt of the hunter is not impaired. Instead of opening as usual in-October 1956, the hunting season on rabbits opened earlier, September 1~ 1956. Reports of :warbles, especially from Gunnison c~unty, prompted the game manager, G. N. Hunter to issue a memorandum to all field personnel. This memo stated that the incidence of warbles would probably decline after Sept. 15. Also, he requested that field men gather information on the incidence of warbles in connection with the earlier opening of the season. Warbles are the ~..ubs· or larvae of flies which infect c~rtain mammals. Most of these flies which attack rabbits and rodents belong to the genus Cuterebra. Althour;h, some authorities place these flies into a separate family, they are related to the warbles of cattle and the nose bot of deer. There is not a great deal Imown about the warbles of rabbits and rodents. Even the accurate identification of the warble is dependent upon rearing the larva to the adult fly ·m damp soil or sand. Generally - the life cycle is as follows: The adult flies which resemble bumble bees mate, and the females deposit e·ggs on the host's (cottontail's) hair. The egg hatches and the small larva burrows into the skin.- The larva, white at first, develops under the skin and forms into a large, dark, often spiny larva about an inch long and half an inch wide. This larva breathes air through a small hole in the skin. When the development in the rabbit is complete, it emerges through the hole and drops to the ground. It then burrows into the ground where it'$ covering becomes thickened forming a case within which the change from grub to fly takes place. This is a stage lmown as the pupal stage. The adult fly .em~rges and the cycle is enacted again. The flies of this genus (Cuterebra) are apparently- quite restricted in their choice of rabbits or rodents. A particular species will most commonly be found in a single species of rabbit but may occur less frequently in other rabbits or rodents. Several species of warbles are lmown to occur in Color.ado. "-1' In the January 1957 Journal of V✓ildlife Management, A. D. Geis gives some interesting information on warbles in southern Michigan. He found the peak infection in August but trailing to the first part of November. Incidence was consistently higher in juvenile than in adult cottontails. Most of the rabbits examined carried less than three grubs per rabbit but one carried as many as eight. Infected rabbits had significantly higher white blood cell counts and heavy infection can apparently cause death. 1ilITTll1fflfiil~i~ BDOW026623 (over) �Page 2. Now for some Colorado data --- . As already stated, a high incidence of warble infection occurred during early September in Gunnison county, where nearly every animal was infected. Stan Ogilvie and Marvin Smith mentioned areas of warble infection about Salida and stated that rabbits were being discard_ed on the dump at Canon City. Dick Denny reported warbles occurring among cottontails in the northwest part of the state. _______________ -~ ______ . __ ___ ---------------In examining rabbits for lungworm, I also checked for warbles and talked with several cottontail hunters in Colorado Springs. None of the hunters I talked to had encountered warbles, all hunted east or southeast of Colorado Springs but in El Paso county. In Septemberonerabbit was shot on Four Mile Creek near Buena Vista that contained twolarge larvae over the rump. It was eaten by personnel on a check station. Three cottontails and five snowshoe rabbits taken by Gordon Seneff and Charles Roberts in Park county were free of warbles. Of eight -cottontails taken in Teller county in October, three of them were infected -- two with immature larvae (white and about 1/2 inch long) over the rump and the third with large larva in the throat region. All were •eaten. In November one of three taken -in Teller county contained an immature warble over the rump - (11/25/56). • As in Michigan, the peak in the inc_idence of warbles among cottontail rabbits occurs in August and declines tl1~reafter. Instances of infection do occur in November and possibly through the winter. The warble and any local in:(la:inmation can easily be trimmed off when the rabbit is dressed. The fla~ of_ the· f~ied. rabbit js not affect_ed in. th.~~atJut..certainly rabbit should be thoroughly cooked before being eaten. Once cooked the meat is perfectly safe. • ff##H##Htl:fl= V �~ Game Leaflet No. May 1, 1957 £ LUNGWORMS IN COLORADO By: R. E. Pillmore - - - At the present time we have neither found nor identified all of the lungworms occurring in Colorado. We do not lmow how many of our wild animals are infected with lungworm, or the effects of lungworm infection on the populations of these ani~als. What actually are lw1gworms? There are two groups of worms, the flat -worm_s~ (Trematode.) and the round-worms, (Nematoda). Some animals includL,g man are infected with flat-worms that attack the lungs, known as lung-flukes. Most of the worms found in the lungs of animals are round-worms or nematodes. Some like Ascaris migrate through the lungs as larvae and mature in the digestive tract, but most of the round-worms which live as adults i11 the lungs belong to a group or family called the Metastrongylidae. This family is composed of several smaller groups. One group infects the lungs of hoofed-animals (sheep, goats, cows, camels, and horses), and the larvae become capable of infecting these animals without developing within another animal. These worms belong to the genus Dictyocaulus. In Colorado, Dictyocaulus viviparous is found in the lungs of mule deer, elk, and cows, while Dictyocaulus filaria is found in the lun~s of bie;horn sheep, and domestic sheep and goats. I have found D. filaria in only one set of bighorn sheep lungs which came from Ouray. • A second group infects swine and the larvae develop in earth-worms, but this group is not known to infect any wild animals in Colorado. A third group infects sheep, goats, goat-antelopes (example - Rocky Mountain goat), deer, and rabbits. The larvae of this ~roup develop in land snails. Several genera arc included in this group but the genus Protostrongylus is most important in Colorado. The following species are found in Colorado: • Protostrongylus stilesi P. rushi P. macrotis . P. sylvilngi P. boughtoni Bighorn sheep (occurs also in R.M. goat) Bighorn sheep (occurs also in R.M. goat) Mule deer (reported elsewhere in pronghorn) Cottontail rabbit, snowshoe hare, (elsewhere in white-tailed jackrabbit) -- Snowshoe hare and white-tailed jackrabbit. All of these species are important to me in my work with lungworm of bighorn sheep .. I will explain a lot more about these lungworms, their importance, life cycle, and possible control in later leaflets. Other groups of lungworms occur i11 Colorado which infect the lungs of bobcats, badgers, marten, and probably other carnivores. Some may be found among rodents (rats, mice, etc.) and insectivores (shrews) as well. #H#ffl:###### W~lliillfOO~ 1f BDOW026624 �Game Leaflet t!fL Date: July 15, 1957 WINTER FOOD PLOTS AS AN AID IN Wll.,D TURKEY MANAGE:MENT By: Donald M. Hoffman Experimentation with the use of winter food plots fenced acainst domestic stock to assist wild turkeys throu~h periods of heavy snows was started in the sprinc of 1953. At the present til~1e there are eight of these in existence on the eastern slope comprisin~ approximately 21. 5 acres under fence and approximately 14. 5 acres in cultivation. Of these eight only tlu.. ee have been in operatior~ long enough to show results. These are the two plots in Sarcillo Canyon in the Spanish Peaks and the one on Pass Creek ir. Huerfano County. Population Increase in Sarcillo Canvon Manac;ement practices in the Sarcillo Canyon area have been limited to the establishment of two wL.,ter food plots of one and three acres, limited predator control, and law enforce1:1ent combined with excellent landowner relations. The following shows the results: Winterinp: Period Food Plot Population Count 1949-50 70 1950-51 Unknown 1051-52 25 1S52-53 3 1953-54 1st year Sakariason 28 1954-55 62 2nd " " 1955-56 3rd " " 91 (add. 5 birds killed in 1st " Mac Donald season) 1ssa-r.1 4th " Sakariason 2nd" Mac Donald 150 (add.11 birds live-trapped) Conclusions and Recommendations for Future Plots: The location of _the food plot is of prime importance. The plot should be located as far fro:~:-. well traveled roads as practical and yet must be accessible to farm machinery • The plot should also be located in a natural wild turkey winterin~ area, a1:d the land owner's cooperation with sportsmen and the Game and Fish Department must be considered. Plots of two or three acres h cul tivatio:1 hold more pro:r:1ise than s:rnaller plots , especially after the flocks facrease to e;ood size. Cultivated oats are the number one choice of e-rain for wild turkeys on the eastern slope and for this reason this has been the mat1 grain raised in the plots to date. Oats is well suited to most of the mountainous types of wild turkey ranr;es. The use of hoc; :C1illet and dry land maize is being used experimentally at present in the drier canyon areas. lli■illllmoo BDOW026625 ##H#### �Game Leaflet No. Septeober 1, 1957 Subject: 11 Game Management THE USE OF BALED OAT HAY IN '\tVINTER FEEDING OF WILD TURKEY By: C. M. Scott -----~-----~------------- ::?rimary purposes of the feeding of wild turkeys are: first, as a supplet1ental winter food supply when natural food is covered with snow; second, during winter periods when crops of natural foods are short due to drouth or other factors; third, to hold the turkeys in their natural habitat, preventing them_ from migrating out of Colorado or into farming and ranching areas or along highways where they are avail-a~le to poachers. When the turkeys remain in their natural habitat, generally in the higher elevations, they are accustomed.to,~the general surroundings and are more apt to observe .approaching danger froJn"predator-s or poachers. - There··rs also the situ-· ation of migrating turkeys going to farm.or ranch yards :where there is domestic poultry and where the wild turkeys may come in contact with diseases of domestic poultry. Past experi~nces have shown-thaJ;.:w.ita,a·little supplemental feeding during times of severe snow storms or drouth conditions, the turkeys can be held in their natural habitat. It was concluded that in order to--pr_qperly care for the turkeys, food would have to be available when depths of snow reached 6 inches to 3 or 4 feet. The idea of using baled oat hay was approached after watching turkeys go to bundled oat stacks on ranches during severe snow storms. The turkeys wouldrfly to the top of the stack and rake the snow off down to ·the oats. This was not a desirable situation as it would not be feasible to duplicate the stacks of bundled oats in some of the remote areas. However, most of the areas could be reached with at least six bales of baled oat hay with grain intact. Two years of experimenting has :g,r-oved the ,following feeding methods very satisfactory. A suitable site is selected that is as re11\f)t.e from farm or ranch headquarters and away from main traveled roads, in:near.proximity of natural food and near water and roosting area. An open area about 16 feet square that is nearly level and near not too dense brush or timber and on a south slope is most desirable. Four posts may be set down, or it is generally possible to find four trees to string barb-wire on to keep do:i:1estic livestock out of the feed enclosure. Wires should be s~ung about 12 to 14 incm3 apart, not less than four wires around the area. The bottom wire should be placed about 18 inches above the ground to provide easy access to and from the feeding area for the turkeys. Near the center of the enclosure, two bales of oat hay are placed on the ground side by side. One wire, is removed from each bale. Place two more bales cross-wise on top of the first two bales, and another bale cross-wise on top of last two bales, removing one wire from each bale. Additional loose grain, oats, wheat or barley may be worked into each bale. It is possible to make larger bale structures according to the turkey population and accessibility of the area during winter months. One bale of oat hay should be broken and scattered around the other bales inside the enclosure. Additional loose grain can be placed in this scratch area to get the turkeys accustomed to 1liiDMiiiiffl~ BDOW026626 �Game Leaflet No. 11 September 1, 1957 Page 2. the feed area. If the area is remote and gen ·er ally inaccessible through most of the winter and the turkey population in the area warrants, it may be advisable to place more bales of oats in the enclosure. It is estimated under average winter conditions, the six bales mentioned above with possibly fifty pounds of loose grain should accommodate a flock or possibly fifty turkeys for two months. It should be remembered that this is only intended as supplemental feeding for occasions of severe weather conditions. -- - - --<-~-lt-lia·s ·been found tliat .tile turkeys prefer natural·. food of some form. if it is at all available. Accordingly, tl1ey visit supplemental feeding areas orily when necessity dictates. Turkeys have been lmown to fly directly from a roosting area a mile or so from the feeding area and land on baled feed or in the vicinity in snow 20. to 30 inches deep and work their way to· the supplemental feed through the snow . . ·when the turkeys get on the bales and start raking or scratching, they soon remove all snow that may cover the bales. With one wire removed from each bale -it is not difficult to. tear the bale apart and find feed. Straw is scattered about on top of the snow and other turkeys find food in this. The turkeys tramping around in the snow and scattering the straw causes the snow to melt rapidly in the vicinity of the feeding area. Turkeys will utilize the feeding area until snow clears from natural-feed areas. Supplemental feeding is beneficial in that the turkeys are •inclined to "winter" better, thus coming -into the spring nesting season in good condition to produce good fertile eggs with good shells. A nest was found in a feeding area in the spring of 1956 that had 20 eggs in it. Eighteen eggs were fertile and hatched. Seventeen of these poults hatched were lmown to have reached mid-stage maturity. After this the brood mixed with other flocks and broods and could not be observed. Other hens were -observed with broods of 8 to 14 poults where supplemental feeding was done in the winter months. Generally_l>rooc}~--------·=-no=tc-:-:ov=e=r-=-:-.-r!'s-:ato77-poults are ci6served where no -~upplementai feeding -is-done. �AGING PHEASANT EMBRYOS Wayne W. Sandfort, Biologist Colo .. Game & Fish Department The ability to age embryos in unhatched pheasant eggs may be of value in several instances. Farmers may seek advice on hatching and rearing pheasants frotll eggs salvaged from nests destroyed during the mowing of alfalfa. Aging an embryo in one of the eggs (perhaps one with a cracked shell) from the destroyed nest would enable you to chsely predict the hatching date. From a managment standpoint, the peak of pheasant hatch, for any given year, could be closely ascertained by aging embryos in eggs from about a dozen nests destroyed in hayfields. Pheasant production on irrigated lands usually is better when the peak of hatching preceeds the peak of alfalfa mowing. A key for field aging pheasant embryos was prepared in 1949, .with cooperation ·from Harry J. Figge, Colorado Game and Fish Department; Dr. Lee E. Yeager, Colo- rado Cooperative Wildlife Research Unit; and.Verna M. Zander, Zoology Department, Colorado A & M College. This key and accompanying photo is shown below: Significant Characteristics : 1st day -- Embryo not flexed (curved), no blood showing in egg 2nd day -- Embryo not flexed, blood first showing 3rd day -- Embryo flexed, -(head only) 5th day --- Dark pigment first shows in eye 7th day -- Eye· conspicuous (dark portion 3 mm. in diameter), brain cavity protruding 9th day -- Toes discernible but feet webbed, egg tooth first appears 11th day -- Feathers first appear on tail 12th day -- Feathers on back and tail but not on head 13th day -- Feathers first appear on top of head 15th day -- Dark feather band first appears under eye region, spurs first appear 16th d&y -- Feathers first appear on edge of eyelids 18th day -- Eye covering first showing dark pigr:.1ented feathers 20th day -- Bottom of feet appearing granular, legs well developed 22nd day -- Dark pigmentation showing at base of toe nails 23rd day -- Upper mandible sharp-pointed, embryo well developed and ready to hatch. ';J/1/57 �oz LI 81 II 91 01 6 SI 8 L �Grune Leaflet No. 12 December 1, 195'7 ORIGIN O.F·BIGHORN LUNGWORMS By - - R. E. Pillmore Contrary to a popular opinion the lungworms suspected to have caused the deaths of bighorn sheep by pneumonia were not introduced by domestic sheep•. Apparently Protostrongylus stilesi ~d the related P. rushi are native to the wild sheep and mountain goats, and have never even been reported from the lungs of · domestic sheep. Other lungworms common to domestic.sheep may, however, infect bighorn sheep (Dictyocaulus filaria and larvae resembling that of Muelleriuscapillaris have been recovered from bighorns). If the bighorn sheep were not iri-~ fected by the introduction of domestic sheep, then they must have arrived in North America with the ancestors of our wild sheep and mountain goats. It is possible that eventually the lungworms of the bighorn might become adapted to domestic sheep • Certainly in Eurasia which is the ancestral home of all the sheep and goats, lungworms very closely related to those of the bighorn do infect domestic sheep. That Eurasia and not North America was the ancestral home of all sheep,. goats and goat-antelopes is virtually certain on the basis of the geological and biological and biological evidence. This evidence is strengthened by a study of the lung parasites and their life cycles. Undoubtedly a connection existed between Alaska and Siberia during the Ice Ages (Pleistocene). The climate varied with the advance and retreat of cont~ental glaciers. The lives of parasites are governed prill)arily by the environment, habits, and physiology of the animals they infect. The variety and number of representatives of a group of animals either living, or fos_sil tends ~o indicate the birthplace of the group.· Fo~ this reason the u.s.s.R. and-adjacent areas are troubled with more kinds of lungworms among both the domestic and wild sheep and goats. Further~ more, the geological evidence supports Eurasia as the place of origin .of both the sheep and the group of snails which serve as the intermediate. hosts for lungworms of the genus Protostrongylus. All evidence considered, we must conclude that the bighorn sheep and · mountain goats, the lungworms,· and the intermc.diate host snails all had their ancestral home in Eurasia. The u.s.s.-R. can probably boast the first sheep or goat, as well as the first satellite, but even at a very early date they were seeking asylum in North America. The next leaflet of this series will explain the life cycle of Protostrongylus. ##### HH#· 1lli1trfiiilmll~I~ BDOW026628 �dame Leaflet No. 12-B January 15, 1958 LUNGWORM 1N BIGHORN SHEEP (Part II) By R. E. Pillmore Life Cycle of Protostrongylus The adult lungworms of several species of Protostrongylus are found in the lungs of bighorn sheep (P. stilesi and P. rushi) , mule deer ( ~ macrotis), cottontail rabbits ( ~ Sylvilagi ) , and snowshoe hares ( E• boughtoni). \Vith the exception of P. r.!!!h!, which has not been studied, the life cycle for all of these species is (z;.sentially identical. The adults ·mate in the lungs, and the females deposit great numbers of eggs in the lungs. Small, first-stage larvae emerge from the eggs which are about 3/2500ths of an inch in length. (Tremendous numbers of larvae are necessary if the parasite is • to persist because the individual larva has a very slight chance of reaching maturity.) These larvae move up the bronchi and trachea to the throat where they are swallowed, to pass through the intestinal tract and out on the ground in the droppings. (First-stage larvae are hardy and under favorable conditions of temperature and moisture may live for more than a year.) The first-stage larvae are not capable of producing an infection in the definitive host unless they first infect an intermediate host which fs a land snail (Pupillidae or Valloniidae families of land snails will serve as the intermediate hosts). Several factors, such as, habitat, habits, abundance, and distribution of both sheep and snails affect the infection of the snails. Active snails which come in contact with first-stage larvae may have their foot tissues invaded by the larvae which burrow in and feed within. Jn the snall.tbe·larva increases several times in size and the gut becomes packed with food granules. The larva then becomes quiet and coverings are shed twice but without the larva escaping _from them. The second covering becomes dark brown and has a ridged appearance. An opening appears in the coverings at the head end but the larv~ may remain in the snail still within the coverings for some time, but is now capable of ·producing an infection or reaching maturity if the infected snail is eaten by the right kind of definitive host. Eventually the larva may leave the snail but if it is eaten along with a bit of vegetation ·by the host it will still be capable of reaching maturity. The time required for the larva to reach an infective stage of development within the snail is quite variable from as little as 11 to 13 days, to 40 or 60 days. The rate of development within the snail is af-fected by intrinsic factors of the snail and the temperature of the environment. Once eaten by the definitive host the infective larva presumably penetrates the walls of the intestines and reaches blood or lymph in which it is carried along to the heart an~ pumped into the lungs. The larvae apparently lodge in the capillaries of the lungs and grow to maturity. The time required to reach maturity in the lungs and for_ larvae to appear in the droppings of the host is between 30 and 60 days. lifi~Jiifflffll~~ BDOW026629 �Page 2. The adult lungworms may not live very long in the lungs of the hosts; however, since the lnngivity of the larvae might exceed a year, live for over a year in the snail, and live for perhaps another year or so after leaving the snail, it is certainly • apparent that a problem develops when heavy infections build-up which can not be quickly remedied. Three sets of lungs from the Pikes Peak herd obtained in 1957 were all heavily infected even though this herd was drastically reduced by disease in 1953. The snail hosts are widely distributed through the state •of Colorado but are not abundant everywhere; therefo:r;e, areas which are habituaµy used or especially attractive to bighorn sheep demand the greatest attention when the snail hosts are abun.· dant on these areas. That is, if the areas are to be managed to prevent the b~d up of lungworm infection of the bighorn sheep, _ For example, we might watch for concentrations of sheep on areas as a result of salt station locations, as a result of restricted areas of good forage resulting from drought or other livestock, as a result of typography as it determines escape cover which must be close by for ewes and lambs, bedding areas, or reserves forage for the bighorn by making it inaccesible to other livestock. vVhen we observe localized use by bighorns we can utilize our knowledge of the life cycle, and determine if the observed use is detrimental to the sheep in so far as lungworm infection is concerned. First we -· might search for snails and if these are present then it is probably an area where transmission of the lungworm. occurs. If no snails are found it does not mean that they arenecessarily absent. A collection of rabbits, if they exist here, may give some indication of the danger to sheep, since the same conditions are apparently as necessary for the lungworms of rabbits as for sheep. In checking further into this problem the types of habitat where transmission of these parasites can occur must be determined. To get more information I would iµ-eatly appreciate the collection of lungs of cottontails, or snowshoe rabbits by ~y interested field personnel. • It would be important to indicate the kind of rabbit, the locality where it was killed, and the k4nd of trees or eover the rabbit was collected in, . pinon-juniper; oakbrush; douglas fir-aspen; spruce-fir; and so forth. Fishery Leaflet No. 12-B January 15, 1958 �Game Leaflet No. 13 Date: July 1, 1958 BUFFALO PEAKS BIGHORN SEASONS By: R. E. Pillmore Kill Figures Buffalo Peaks Area Total Permits Permits Sold Kill Rams 10 10 9 1954* Sept.11-19 '70 64 12 1955 . Sept. 3-11 10 10 Season 1953 Sept.3-13 1956 Sept.1-9 Ewes Lambs Total 9 17 33 51% 1 1 10% •. 20 .. 4 4 20% 60 164 ._12 38 · 32 53% 48% 4 • I 20 Success Ratio Uncl. .. ·•· • 195'7* .. ' ' _79_ 180 * Either-sex seasons Aug. 31 Sept. 15 . 15 32 ; ~ . i. - --L. 2 6 3'.:- '79 --------------~------------~---------------------------~--~---------------------~ ,.. • 't } ... The Buffalo Peaks herd on the west side of South Park and north of Trout_ Creek .. i. Pass is a n~tive herd of bighorns which prior to losses in 1923, attributed to hemorrhagic septicemia, numbered several hundred head with about a hundred head- crossing from Mt. Yale to winter in the vicinity of Midland Hill. The herd was increasing during the 1940's. In 1952 a party reported .seeing about 60 head of ewes and lambs, and during the deer season the same year a hunter reported seeing about 30 head of rains. Ten ram permits were established for the 1953 hunting season. Nine rams• were killed, all on the Alpine portion of this range, and all were infected with lung- _. worm. In Yiew of the lungworm infection and the 1923 epizootic it seemed advisable:. to attempt a reduction of this herd to try and avert a recurrence of the epizootic, such as had already happened in the Pikes Peak and Tarryall herds. An either-sex season with 70 permits was established for 1951. Field observations during 1954 revealed concen.trations of ewes and lambs on the alpine range and snail hosts for lungworm were also fcund on the alpine range. ~ Field investigations in 1955 revealed as many, or more, sheep present on the alpine range as were seen in 1954, from which it seemed logical to conclude that the season had accomplished little more than remove the increase of the herd. (over) liiillii1tii BDOW026630 �Page 2. . :. Game Leaflet No. 13 • July 1, 1958 Buffalo Peaks Bighorn Seasons By: R. E. Pillmore •.·• During the 1955 season only one hunter was successful, yet in November, when ~-a_.group of sheep_ wer~ taken fo~ a museum, 12 of 46 head of sheep seen (~o ~~].ic~tio!l __ likely)--were legal rams (half curl or better). Recommendations were made for an-. either-sex season in 1955 and 1956 for 50 permits; each met with political opposition. Another either-sex season was held in 1957 for which '10 permits were established. One thing found of possible significance with respect to future values of the area in trophy hunting was the high proportion of yearlings, '1 of the 12 rams taken were yearlings, and all rams were less than 7 years of age. Only one of the hunters apparently saw any of the older rams. It should be stated -also, that the lungs of the yearlings, in general, were heavily infected with lungworm, with the infection being more diffuse and not localized into well defined nodular lesions as was found with many of the older animals. All lung samples obtained from the Buffalo Peaks area have exhibited some degree of lungworm infection. Since the first hunting season in 1953, 79 bighorns have been _killed, or about 30% of the state-wide kill of 266 _sheep has come from this one area. We have not reduced this herd by hunting but have realized a significant harvest by hunters. r. H:/J:##=Jl:HH i..._; �Game Leaflet No. 14 March 15, 195S RABIES AND Wil,DLIFE By; R. E. Pillmore Rabies has been reported from a great variety of warm-blooded animals, which include the following wild species: Wolf, coyote, fox, skunk, badger, weasel, bear, raccoon, elk, deer, antelope, rabbit, porcupine, gopher, marmot (woodchuck), squirrel, rat, mouse, mole, several species of insectivorous bats and hawks and owls. Man and his do.mestic animals may also become infected, especially dogs which are frequently victims of this disease. In the graph, the relationship of the reported cases of rabies in dogs to human cases of the disease is readily apparent. In this same graph you will notice that while the reported number of cases for dogs is declining, the number of miscellaneous or wildlife cases is apparently increasing. The reason for this upward trend of rabies in wild animals might be explained at least in part by an increased interest in the wild animals carrying rabies; for example, from the first reported cases in 1953 to 1957 there were 175 laboratory-confirmed cases of rabies in insectivorous bats from 17 states. Another explanation might be increasing population densities of the important "carrier" species, such as foxes and skunks. Were it not for certain wild species some officials believe rabies might have been eliminated long ago. ~ Wilcllife agencies, such as the Colorado Department of Game-and Fish, and the United States--j!isb and Wildlife Service have a dual responsibility -- to the wildlife and to the public -- with respect to sylvatic rabies. The term sylvatic is used to distinguish the diseas.e as it occurs in wild animals from the disease as it occurs in the citios or among man and dogs. Rabies is caused by a virus affecting the central nervous system and occurring in the saliva of the infected animal. The disease is, thus, transmitted from animal to animal through the contamination of bite or wound with the saliva. This leads us to two important considerations in an area at any particular time, these are: (1) The number of animals already infected with rabies, and (2) the number of susceptible animals. Rabies is a fatal disease and once symptoms appear the animal is doomed, but preventative treatment when started early enough may save an exposed individual. This prophylactic treatment is described as being expensive and painful consisting of a series of 14"!"21 injections with a vaccine; use of an anti serum is recommended as an adjunct to the use of the vaccine. About 60, 000 persons in the United states are given this treatment annually. The duration of the disease after symptoms appear is short, only 3 to 7 days-, but the virus may be present in the saliva about 3 days before symptoms appear; therefore suspect animals (especially those which have bitten some person) should be confined for ten days. Then if the animal is still alive and has shown no symptoms it may be safely released, and unless the exposure has been severe or close to the central nervous system , the bitten person is spared the preventative treatment. Since the disease is fatal and of short duration, we should be able to predict the course of the disease in a given population of species of susceptible animals, but the habits of the species, and the symptoms produced must first be lmown. Certainly the size of the animal, its mobility, and ability to inflict a severe bite are important in determining the spread of the disease in the susceptible population. In general if the population were small �Game Leaflet No. 14 (2) By: R. E. Pillmore 3/15/59 enough, rabies could not maintain itself even if introduced into it. At the other extreme if the population were sufficiently dense the number of clinical cases would rise sharply and most animals in the population would be exposed, with the end result being a population level well below the one which could not suppo~ the disease. Thus, you have two theoretical extremes; one a population in which rabies would quickly die out and the other in which rabies would die out only after practically exterminating the entire population. Most natural conditions where rabies occurs will lie between these extremes and the length of time that rabies might persist in a natural population would be longer at the lower population densities between the extremes metltioned, and theoretically there would be a level of population density which would support rabies indefinitely. For Colorado, the laboratory-confirmed cases are tabulated in the accompanying table. In order to appreciate what this information means, it must be pointed out that the State Health Department Laboratory does not routinely examine for rabies from a county where the occurrence of the disease has already been established. An exception is made when a person has been bitten by a suspect animal or some other circumstance makes it advisable to attempt confirmation of rabies. Positive rabies diagnosis is accomplished by examining brain tissue microscopically for specific pathological changes called Negri (after their discoverer) bodies. Unless the disease is allowed to run its course or into the late stages the Negri bodies may not be sufficiently numerous to be observed. In this case confirmation may be obtained by inoculating the brains of mice with brain material from the suspect animal. Suspect animals are submitted to the laboratory because of biting someone, abnormal behavior, or being found freshly dead of undeterminable cause. Game department personnel, because of the nature of their work and knowledge of wildlife, can provide a valuable service within the realm of their responsibility in recognizing a suspect animal and submitting it to the laboratory. From field observations they may determine whether control is indicated, and cooperate with the u. s. Fish and Wildlife Service in carrying out a control program against the affected species. Control programs would be initiated to contain and prevent the spread of rabies especially if high population of susceptible animals existed in surrounding areas. Any suspect animal encountered by department personnel should be handled as follows: 1) Jf the animal is taken alive, especially after biting someone, it should be confined in an escape-proof pen or compartment and public health authorities notified. 2) If the animal must be killed it should not be shot in the head. The head should be cut off and packed in wet ice, (do not freeze) but before submitting to the State Health Department Laboratory, state Office Building in Denver, Dr. Martin Baum or the Veterinary Services Section of the State Health Department should be contacted by phone, stating location and details, then, if they are interested, obtain further instructions. 3) In the event a freshly dead animal is encountered in the field, the possibility of gunshot, being hit by car, or other accident should be ruled out before it is considered as a rabies suspect and if possible a post-mortem performed to determine any other obvious cause of death. Symptoms which might indicate rabies are of two types -- the "furious" and the "dumb" form. In the first there is restlessness, irritability, tendency to wander, tendency to snap or to seek out dark corners. Later a partial paralysis, staggering gatt, and finally complete paralysis and death. With the dumb form the only important symptoms may be paralytic; the animal may not be able to close its jaw. Loss of flesh, or emaciatim, is apparent even with the short course of the disease from 3-7 days. The presence of �Game Leaflet No. 14 March 15, 1959 By: R. E. Pillmore unusual items in the stomach on postmortem examination may suggest rabies, but there is no characteristic post mortem finding to diagnose rabies. One of our jobs as wildlife managers is to determine what constitutes a healthy, productive population, and then work to maintain this condition through harvest or other management techniques. This applies in the control of sylvatic rabies and to the fox, skunk, and coyote reservoir populations in particular. Control programs are expensive and regulation of these populations through hunting or trapping is to be encouraged. In March 1954 there were 8 cases of rabies involving dogs, cats, cattle and hogs at the little town of Segundo west of Trinidad in Las Animas County. Control was instituted by personnel of the Game and Fish Department and the U. s. Fish and Wildlife Service and no--further cases were reported in this area. LABORATORY - CONFIRMED CASES OF RABIES IN COLORADO 11.\!. ~EQ.~'!: Y~~H3 Year Species & No. of Cases . 1958 1957 1953 \.,I 1945 - 1954 ! Remarks -------·-··--- -------,·---Douglas Lincoln Kit Carson Elbert 3 2 1 1 Total cases for year - Mesa La Plata Arapahoe Larimer Kit Carson 2 1 1 1 1 Total cases for yr. Bats 2 1 1 2 Dog Skunk 1 1 Weld 2 Total cases for yr. Skunks Coyotes Dogs Fox Skunk 1956 Count~es & No. of Cases 5 2 7 6 2 No cases reported 185 cases ( USDA Year Book Agr.) 1956 �Game Leaflet No. 15 April 15, 1959 ... ., ····· .. ·.. LUNGWORM AND LAMl3S By: R. E. Pillmore ... _1• . ·• tllii1illitnn . eoow026632 I/I/fill In the Music Pass - Sand Creek country of the Sangre de Cristo Range there ar.~ some bighorn sheep. According to W. c. o. Dan Riggs most of the ewes in this area ha~e laml?s with them early in the summer, but only a few of these ewes still have lambs with.-them.by fall. During the bighorn hunting season, I believe it was 1956, some of the h'11lte~s ~~re able to catch a lamb and then released it -- ~ey could never have caught a h~~~y lamb!. Obviously, something is happening to the lambs, for the Crystal Creek herd in~.VJyoming, Honess and Frost (1942) stated that 50 percent of the lambs die after reaching ari age of · . . about six weeks. This loss was attributed to a bacterial pneumonia of a contagious nature. Some such failure in bighorn lamb crops has been lmown o.r suspected in various localitief3 for years, but has been explained by predation, wet weather,- disease, poor range, and ~. nutrition. Actually, all of these f~ctors probably play a part, but whai is the most impor-- •. •, tant or key factor? '---' In a parasitology text by Monnig we encountered the statement that prenatal infection (becoming infected before birth) occurs with Dictyocaulus! :iilfections, •and have wondered if similar infection with -~strongylus might not offer a possible explanation for this lamb loss. ll11 February. 1940 a bighorn ewe, named "Clarissa," was penned at the·City Park Zoo in Denver, Colorado where she had a lamb·born on June 1. Herb Wallace, technician for the Game and Fish Department at the time, visited the lamb on July 19 and observed that the lamb was in poor condition with a rough ·coat, coughed and breathed with difficulty on exertion. The lamb ·was found to be infected with lungworm, in spite of the fact the pen was dry and no snail intermediate hosts known to be present. Wallace believed from this experience that no intermediate host was necessary and that Protostrongylus stilesi had a direct life cycle like Dictyocalus. • From the Buffalo Peaks_ ,herd I collected droppings from lambs, probably not more than a month of age, and recovered lungwo,rm larvae from them. It was established that. tirststage larvae failed to change in appearance outside of snails and that when these larvae were fed to a sheep they could be recovered again from the droppings of the sheep, unchangedo This is good evidence that an intermediate host is essential for infection with Protostrongvlus. • In Wyoming, six bighorn ewes w~re tr~pped near Dubois in January. 1956 and penned at • the Sybille Station in a large enclosure which had had· no use by livestock for several years. Five of these ewes had lambs, which Kenneth Winter· found passing lungwo~m larva~ in the . feces when he checked them in July. The lambs did well, however, and were -noticeably larger than lambs among the sheep trapped from· the same locality as the. others in Jan\lary 1957. All were penned together, and tµ February disease took•its:toll of this herd, but this loss was not confined to lambs (Post, 1958). When I visited the Sybille Station fn February about the time the first sheep died, Dr. Honess and I found snail hosts· within the enclosure and along the creek. All available. evidence suggests that prenatal infection with Protostrongylus might occur, but it· is inconclusive. From the Rampart Range herd of bighorns two ewes were trapped--''Lucy" in January 23, 1958 and "Alice" on February 4, 1958 at Glen Eyrie and penned at the Denver Federal Center (a third ewe was caught but escaped over the eight-foot fence). The enclosure was �Game Leaflet No. 15 -2- April 15, 1959 about . 3 acre in area and no snail hosts could be found within. Lucy had her lamb on May 23 and Alice not until July 2. Both of the lambs died; Lucy's on July 13 and Alice's on July 7. Fecal samples were collected almost daily, and no lungworm larvae could be demonstrated until June 23 following which some larvae were recovered from each of the samples, but only in small numbers. For two weeks before Lucy's lamb died, it was apparent that it was not doing so ·well, and four days before death it stood. and allowed itself to be caught after running only twice around the pen. It grew progressively weaker, coughed while feeding and finally died. This lamb appeared stunted but was not emaciated. Autopsy failed to show a good cause for death, with only the lungs appearing somewhat more consolidated in texture than norm.al but no pneumonia was found. A dorsal hypostatic congestion due to position of .lamb after death was ·a1so evident. Posterior tips of the lungs were found heavily infected wlth llll'igworm, Protostrongylus stilesi and no bacteria were cultured from the :maedia -innoculated. ·-Anc;,ther lamb was picked up in the Buffalo Peaks area w~en only a few hours old and still unable to follow the ewe. This lamb has been penned.at the Cheyenne Mountain Zoo -~---,-=-w1th a domestic milk.goat· as a foster mother. Ther~.has been no contact with"an'infected"· bighorn. sheep since its birth. The Cheyenne Mountain Zoo has not had a bighorn sheep since the 1930's and the hybrid sheep in the adjacent pen to the goat and lamb are not infected with lungworm (repeated fecal checks have been made and some hybrid~ have been used as experimental animals where infection has been established artificially in only one out of seven animaj.s exposed.) Search within this enclosure failed to reveal any snail hosts. Yet fecal samples (collection was much less frequent than for lambs in Denver, only about once a week or less) were collected on June 23, just thirty days after birth, three lungworm lar-vae were recovered, and from each sample since that date some larvae have been recovered. • • •• • This last example, •with the other eVidence, is strong argument for the existence of a prenatal infection of bighorn lambs with this lungworm. The delay of about thirty days from birth until the larvaEHirst appear in the feces is probably related to some physiological need of the parasite that for their development to the adult stage the lungs they inhabit be functional. Another possibility is a resistanQe ;mechanism of the infected ewe in which there is a chemical inhibition of the infective larvae_' s development which may be transmitted to the lamb during its uterine life as a fetus. For the lamb to become infected, the infective-larvae must get into the blood circulation of the ewe, come into. contact with the placenta, penetrate it, and enter the separate blood·supPly of the fetus. Whichever, tlie mechanism for d~laying the development of the lungworm larvae in the fetus, the circum~~~ces. are prob.ably such that all larvae pr~sent may develop at the same time. The size of this prenatal dose may, therefore, have a direct bearing on the survival chance of the lamb. This has not been demonstrated, but certainly the burden of a heavy lungworm infection increases the obstacles to survival or impairs to • some extent its chances of overcoming other .obstacles which each lamb must face. We are, however, still faced with the problem of Im.owing what relationship exists between lungworm in.lection and mortality. Jf the l~gworm infection caused the death of the penned lamb from the Rampart Range herd then it might be expected that the survival of the wild lambs in the mother herd would also be affected. With this in mind, the numbers of lambs were tallied among the sheep coming down on the lawn.s this year at Glen Eyrie. The best classified count - free of any ~plication was: 10 rains, 23 ewes, and 17 lambs. There is considerable difference in the size of these lambs and some have been observed coughing. There has been no failure of the lamb. crop as might have been expected if lungworm infection had caused any significant mortality; however, in 1957 the lamb crop was at least 12 lambs-over half of which were Im.own to be males, yet only 2 yearling rams have been observed this year. This might indicate the occurrence of significant mortality among this age group during the spring or summer months but this is speculation. • �Game Leaflet No. 16 June 15, 1959 .PHEASANT-INSECTICIDE STUDY REPORT By: James Tigner, Graduate Student The increasing use of insecticides in crop and rangelands has created speculation amorg wildlifers as to the direct and indirect effects these chemicals may have on bird, mammal, and fish life. Although plant killers such as 2, 4-D certainly have indirect effects upon wildlife, generally no deaths occur outright. Various state conservation agencies have conducted insecticide studies, but most inves;... tigations have been either tests conducted under controlled conditions or searches for and examinations of dead wildlife in an area previously sprayed. It was felt that neither method , could produce as clear a picture of the situation as a test conducted under field conditions. With this in mind, two agricultural regions in eastern Colorado, specifically the South Platte and-Arkansas ·River valleys,· Were chosen foraplieasant-irisectic"ide study. Questiomiaires~were sent by E. w. Mustard, graduate student at Colorado State University, to aerial sprayers and county agents in eastern Colorado to determine kinds_ of insecticides most used and crops most heavily sprayed. These crops and insecticides are: Alfalfa (1) Heptachlor (2) Dieldrin (3) Toxaphene; corn (1) Parathion (2) Aldrin (3) Dieldrin; wheat (1) Endrin (2) Dieldrin (3) Parathion. The field and spraying dates were obtained through cooperation of landowners and aerial· sprayers, Several tests were conducted with the use of a ground spraying rig mounted on a farm tractor. Thirty-four pheasants from the Experimental Game Bird Farm at Rocky Ford constituted the full component of the test. Two 8 x 8 x 4 foot pens held nine birds (six chicks, two hens, and one cock). Two additional pens held only eight birds, due to shortage of rooster pheasants. The age of the chick, of course, \raried through the summer. Three pens were placed in a direct line and equidistant in the center of the field to be sprayed. It was found that in this manner the coverage would be most complete. A control pen was placed in another field of the same crop in a location certain not to be sprayed. The birds remained in the field two days after spraying. In order of increasing insect toxicity, the chemicals are: Toxaphene, Aldrin, Hepta_chlo!, Die~d~in, -~ndrin, and Parathion. As_~ ~~:p;ipa~ison, _Toxaphen~•~J~thalJtyJ~ on_par with DDT. Parathion is an organic phosphate (the others are chlorinated hydrocarbons) and is considerably more potent. However, one test conducted in seed alfalfa using aerially applied Parathion at the rate of eight ounces per acre produced no fatalities. Dieldrin at six ounces per acre, and Endrin at 6. 5 ounces per acre have as yet killed no birds. In a test near Ovid, Colorado, using four ounces of Aldrin per acre, two test chicks (age 6 weeks) died. The test became somewhat inconclusive, however, with the death of a control chick. A 1. 5 pound per acre test of Toxaphene resulted in sick chicks, but to date none have died. Heptachlor has not yet been tested. In addition to the above chemicals, rothane, a dust probably comparable in toxicity to Aldrin, was applied aerially at a rate of 30 pounds per acre. One chick has died as a result. • lillliiliifi BDOW02aa33 �Game Le~et'No. 16. June 1s; 1959 Continued: In conjunction with ijte above outlined study, ins~ct populations in sprayed and unsprayed areas _were.~ompa:r~~- The data have not been anai.yzed. Because·certain insecticides .have been-lmo:wn-tp atroJ?hY pheasant ovaries were-talcen·internally,-the-test birds will be . held at Rocky. F.ord over the winter until next breeding season .. The birds will then be segregated-:as to test and th~ fertility and hatchability of the eggs and tile survival of the young will be investigated. 0 It must be noted that although these tests have as yet produced no definite evidence of . c;Ietrimental effects on pheasants, the sample is small and ce~ainly not taken under all weather conditions. High temperatures. and humidity increase the killing power of certain insecticides and under those conditions, pheasants might be less tolerant of the chemicals. ·l I HHffl::fl:ffl:HH .... �Game Management Leaflet No. • October 30, 1959 17 NEW POSSESSION LIMIT ON PHEASANTS EXPLAINED By --- Hal Swope When the Colorado Game and Fish Commission set the 1959 pheasant season, they liberalized the possession limit. The daily bag limit remains at three, but the possession limit will now go to nine rooster pheasants instead of three as before. ·,, There is much information to support this change, but hunters should not jump to the wrong conclusion that the possession limit was increased solely because there are more birds this year. It is'true that pheasants have thrived in most areas during the past several years but there are other facts of equal importance to consider. The increased possession limit is a step forward for Colorado in pheasant management -not just because there are more birds but because we will now be able to better manage the birds we do have. Colorado is one of the few midwestern states and provinces which has not permitted a possession limit in excess of the daily bag in recent years. The new limit will first of all benefit t.lte sportsmen who must travel long distances to hunt pheasants. There will also be a great general benefit to businesses within the major pheasant areas (motels, hotels, restaurants, service stations and the like) ~hich will profit from the extra days that hunters will stay over to hunt for the extra possession limit. Almost all data collected in Colorado and other pheasant states prove that extra possession limits provide better management. First of all the Colorado pheasant sex ratio following the hunting season is approximately two hens to one rooster. Experience in other states has proved that this ratio can easily be six to one or better with fertile egg production unaffected, The additional roosters over and above normal sex ratios are surplus and should be harvested each year rather than be wasted to climatic extremes, and natural losses in the wild. Experience in other states has also proved that liberalization of the possession limit will accomplish additional harvest of roosters without jeopardizing total flocks and breeding populations. South Dakota, one of the leading pheasant states in the nation, had a daily three-bird limit but allowed a possession limit of fifteen birds in 1957. Pheasant prospects for that state in 1959 are better than ever, indicating that even such a liberal possession limit did not adversely affect production of birds. Federal regulations have always allowed possession limits in addition to daily limits on migratory waterfowl with no ill effect. Hunters are cautioned that under the new liberal possession limits the daily bag limit still applies. Hunters will only be allowed three birds per day, but if they wish to stay over and hunt addition-al days, they can, in three days of hunting, reach their full possession limit of nine birds. ., ( • -. It must be emphasized that liberalization of the possession limit 1n Colorado will work only if hunters obey the letter of the law and conform to daily bag and . • .. . possession limits. ' ~ f 1ilOO~liOOiii1iOOOO BDOW026634 � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Game Information Leaflets Description An account of the resource A series of short leaflets published by Colorado Department of Game and Fish from 1956-1959. Written by agency personnel the leaflets were intended to help staff answer questions put to them by the public. Contents: #1- Methods of Hunting Pheasants, by Wayne W. Sandfort (10/1/1956) #2- Care of Big Game Hides (10/15/1956) #3- Wild Turkey Hunting Techniques, by Martin Burgett (11/1/1956) #4- Productivity Rates, Age Classes, and Sex Ratios of Spring-caught Beavers in Colorado, by Wm. H. Rutherford (11/15/1956) #5- Artificial Revegetation on Big Game Winter Ranges, by Claude E. White, Jr. (12/1/1956) #6- Some effects of Heavy Use on Browse Plants, by Harold R. Shepherd (12/15/1956) #7- Some Sex Determinants of Game Animal Carcasses, by Richard N. Denney (1/15/1957) #8- Warbles of Cottontail Rabbits, by R. E. Fillmore (4/15/1957) #9- Lungworms in Colorado, by R. E. Pillmore (5/1/1957) #10- Winter Food Plots as an Aid in Wild Turkey Management, by Donald M. Hoffman (7/15/1957) #11- The Use of Baled Oat Hay in Winter Feeding of Wild Turkey, by C. Scott (9/1/1957) #11A- Aging Pheasant Embryos, by Wayne W. Sandfort (9/1/1957) #12- Origin of Bighorn Lungworms, by R. E. Pillmore (12/1/1957) #12B- Lungworm in Bighorn Sheep, by R. E. Pilmore (1/15/1958) #13- Buffalo Peaks Bighorn Seasons, by R. E. Pillmore (7/1/1958) #14- Rabies and Wildlife, by R. E. Pillmore (3/15/1958) #15- Lungworm and Lambs, by R. E. Pillmore (4/15/1958) #16- Pheasant-Insecticide Study Report, by James Tigner (6/15/1959) #17- New Possession Limit on Pheasants Explained, by H. Swope (10/30/1959) Each leaflet is cataloged separately in the library catalog and available in print form at: SK 325 .G21. Alternate title for series: Game leaflets. Creator An entity primarily responsible for making the resource Colorado Department of Game and Fish Subject The topic of the resource Wildlife management -- Colorado Big game animals -- Colorado Game birds -- Colorado Furbearers -- Colorado Rights Information about rights held in and over the resource <a href="http://rightsstatements.org/vocab/InC-NC/1.0/">http://rightsstatements.org/vocab/InC-NC/1.0/</a>