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Forestry research west PDF

30 Pages·1993·1.7 MB·English
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Historic, Archive Document Do not assume content reflects current scientific knowledge, policies, or practices. » \\ F F .3 \ Forest Service XI October 1993 A report for land managers on recent developments in forestry research at the four western Experiment Stations of the Forest Service, U.S. Department of USD A Agriculture. ■ • ?qp? ARY mo ■T 23 D 03 — ’T "p: M -UCGRPS ---r. —L_--- In This Issue ©T_. o^ y O^ ^r j < dj 4->e\ u rO DfiMiwi i ^ Western Forest page Publications Experiment Electronic eartags: reinventing Stations Single copies of publications the fence 1 referred to in this magazine are Sugar pine and blister rust: available without charge from the Pacific Northwest Research Station a not-so-simple genetic solution 7 issuing station unless another (PNW) 333 S.W. First Avenue source is indicated. See page 23 Portland, Oregon 97204 for ordering cards. Developing tools and methods for ecosystem management, Each station compiles periodic Pacific Southwest Research A research-management lists of new publications. To get Station (PSW) partnership 11 on the mailing list, write to the P.O. Box 245 director at each station. Berkeley, California 94701 Lichens as biomonitors? 16 New from research 18 To change address, notify the Intermountain Research Station magazine as early as possible. (I NT) Send mailing label from this 324 25th Street magazine and new address. Don't Ogden, Utah 84401 Cover forget to include your Zip Code. Rocky Mountain Forest and Private rancher Dave Baker at¬ Permission to reprint articles is not Range Experiment Station (RM) taches a special eartag to a heifer. required, but credit should be 240 West Prospect Street The tags are part of an experiment given to the Forest Service, Fort Collins, Colorado 80526-2098 being conducted by Pacific North¬ U.S.DA. west Station scientists. They are working on a system to control Mention of commercial products is livestock movements by training for information only. No endorse¬ them to respond to remotely con¬ ment by the U.S.D.A. is implied. trolled auditory and electrical stimulation. Ultimately, they intend to develop an inexpensive electronic fencing system that will prevent cattle from entering designated areas such as riparian zones. Details begin on page 1 . D Electronic by Les Ozawa Pacific Northwest Station eartags: reinventing the fence Riparian ecosystems sustain life Limiting livestock access to But fences have drawbacks. and livelihoods far beyond the riparian areas is an obvious Especially in mountainous, rocky streambed itself. Research solution. The question is how. terrain, they are expensive to indicates intensive grazing of a Costly solutions include closing off build, up to $5,000 a mile, accord¬ riparian area can adversely affect grazing allotments or using ing to one estimate. Fences also a stream’s water quality. Over- herding more extensively. Fencing are not selective. “They keep grazing can also quickly reduce is a more common solution. For cattle out, but they also block vegetation diversity and centuries, man has used rocks, access to the recreating public,” streambank structure. It is not wood, and wire to construct said Tom Quigley, a range scien¬ surprising then, that cattle grazing physical barriers to prevent tist with the Pacific Northwest in riparian areas on public lands is access into and out of a pre¬ Research Station's Blue Mountains under intense public scrutiny. scribed area. Natural Resources Institute in La Grande, Oregon. “Wildlife can get caught up in fences,” he added. Fences require gates and are prone to damage from flooding. Fences are also more or less permanent. Land managers need to be very careful about where they place them, because once they are in, they likely will be in place for a long time. Advantage of electronic fences Can cattle ever live compatibly with salmon and other denizens of our forests and rangelands? Taking a cue from dog trainers using electronic collars, Quigley and Art Tiedemann, a fellow Forest Service scientist in La Grande, are developing a way to control livestock movements by training Texas yearling steer wears insulated them to respond to remotely electronic eartag number 8. controlled auditory and electrical stimulation. Ultimately, they intend to develop an inexpensive “elec¬ tronic” fencing system that will prevent cattle from entering designated areas such as riparian zones. 1 Electronic fencing has two key advantages. First, it allows selec¬ tive access. Through coded signals, a certain herd could be kept away from a prescribed area, while other animals (including humans) are allowed free access. Second, the “fence" is “portable.” By turning off the transmitters and moving them, land managers can “obliterate” and set up fences at will. When tests on four steers with modified dog collars in 1990 proved promising, Quigley and Tiedemann took their idea further: they began work to improve the technology and to develop tech¬ Prototype electronic eartag can be niques for use on cattle herds in programmed for various warning patterns. controlled field conditions. “We switched to eartags, because collars are expensive to build and difficult to handle on cattle,” said Quigley. “Eartagging is done routinely by livestock people, and if we could get the unit contained in an eartag, animal handling would be reduced tremendously,” added Tiedemann. With a $99,000 EPA grant, Quigley and Tiedemann contracted with Schell Electronics of Chanute, Kansas, to design and manufac¬ ture transmitters and receivers for the system. Hand-held unit can activate, deactivate and test electronic eartags. 2 wedges of a pie, each 1,600 feet long, 30 feet wide at the narrow end, and 800 feet wide at the outer edge (see fig. 1). Several transmitters were aligned to establish exclusion boundaries at various distances from the narrow end of the pasture. The researchers learned several things from the Texas tests. “We learned it is essential that the animals are trained before they’re released in areas with electroni¬ cally defined exclusion zones,” said Tiedemann. After testing various training regimens, Tiedemann and Quigley feel a temporary electric fence aligned Training pasture configuration for Texas to the transmission zone may be If, however, the animal remained tests. all that is needed. The researchers in the exclusion area, after four learned that it is important to seconds it would receive a mild identify and properly train lead electrical stimulus. The animal The prototype eartag is 3 inches animals in a herd. The other could be electrically stimulated up wide and 6 inches long, about animals would sometimes follow to two more times, with 4-second twice the length of a conventional the lead animals into the exclusion pauses between each stimulus, to identification eartag. When insu¬ zones, even though they had to allow it time to move outside the lated and fully equipped, the endure the full series of electric exclusion area. Thereafter, the eartag weighs 4 ounces. Power is stimuli. receiver automatically “locked up” supplied by two AAA batteries. (shut itself off), to protect the The portable transmitter, also built animal. To develop range control by Schell, is designed to transmit The Texas tests also led to techniques, Quigley and a coded signal continuously. It changes in the eartag stimuli. The Tiedemann took their electronic can transmit at five different signal animals seemed to react to insects devices to Texas and Nevada for strengths, so its range can be in the same way they reacted to two field trials last summer. adjusted between 100 and 500 the high-pitched (8,500 hz) tone. feet. Also, the electric stimulus of 1 second caused some animals to The Texas tests wheel around completely instead In mid-June 1992, in cooperation The eartag was originally de¬ of turning away from the exclusion signed so that an animal would with the Texas Agricultural Exten¬ zone. For the follow-up Nevada first receive a warning in the form sion Service, 90 yearling steers tests, the eartags were modified to of a high-pitched sound, if it were tested for 9 days at the Scott emit a lower-pitched (850 hz) tone. approached a transmission Petty Ranch in Yancey, Texas. The The duration of the electric stimuli (exclusion) area. If it moved away, pastures were shaped like was shortened to 1/8 of a second. it would receive no further stimuli. 3 Another important modification The Nevada tests relatively flat, open valley about was a change to the stimuli The Nevada tests took place in 1.5 miles long and a quarter to half pattern. “We wanted the animal to August at the Great Basin National mile wide. Its riparian area con¬ associate the auditory stimulus Park at Baker, Nevada, with 90 sists of conifer and aspen inter¬ with the electric stimulus,” said yearling heifers provided by Dean spersed with small openings. The Tiedemann. The researchers Baker Ranches. The study site valley itself is sagebrush grass¬ reprogrammed the eartag so that was the Strawberry Creek basin, a land. the animal would hear an audible tone before each electric stimulus It was hoped the animals would learn to react to the warning tone, move out of the exclusion zone, and avoid the ensuing electrical stimulus. A major innovation to the transmis¬ sion-receiving system was the addition of a remote unlocking transmitter set up in an “unlock zone"—an attractive area like a water, salt, or mineral location outside the exclusion zone. Animals with locked up receivers that moved into an unlock trans¬ mitter zone would automatically have their eartag receivers reacti¬ vated for future encounters with the electronic fence. Transmission difficulties occurred during the Texas tests. Because higher humidity at night seemed to increase signal distances, trans¬ mitter strengths were lowered at the end of the day to maintain the exclusion zone in the pasture. Also, when animals grazed close together, some animals blocked signals from reaching receivers on nearby animals. This resulted in some animals getting confused when they were stimulated incon¬ sistently because of signal interfer¬ Strawberry Creek basin, Great Basin ence. National Park. 4 Three control and three treatment pastures were set up, each consisting of a section of the stream, a riparian area and a grazing area. The pastures were 500 to 800 feet long and 250 to 400 feet wide (see fig. 2). The Nevada tests confirmed that electronically eartagged cattle quickly learn to avoid an exclusion area when an electric fence is used as a visual cue during training. During a 1-day training period, the researchers observed 23 correct responses and 2 incorrect responses among treatment animals approaching the electronic fence. After being trained, the animals were moved into the test pastures around Strawberry Creek. Over the next 3 days, researchers observed the electronically eartagged animals make 32 correct responses an 4 incorrect responses when they approached the exclusion areas. Some of the incorrect responses were attrib¬ uted to defective eartags that were apparently damaged when the cattle were trucked up a primitive road to the Strawberry Creek pastures. tions for Nevada tests. 5 But the electronic fence worked. “We also didn't have time during Many private and public partners During a 1-day test, all the animals these short trials to see if the have cooperated in various in a treatment pasture stayed animals could be sufficiently phases of the electronic fence outside the electronically defined trained to respond to audio research. They include two exclusion zone. In contrast, in the warnings alone, so that they would ranches, four state agencies, five control pasture, cattle were learn to avoid receiving electrical Federal agencies, a state univer¬ observed 44 percent of the time in stimulation,” said Tiedemann. sity, a private foundation and an their “exclusion zone.” electronics firm. During summer 1993, with a “The Nevada tests reinforced our SACHEM Fund grant, Quigley and How long will it take for electronic optimism from the Texas tests that Tiedemann worked with Oregon eartags to be on the market? the technology is there and can State University scientists to work,” said Tiedemann. “Lowering assess the influence of eartag the pitch of the auditory signal and stimuli on animal health, physiol¬ “Optimistically, if the stars line up shortening the duration of the ogy, and behavior. They also and we continue as planned, in 2 electrical stimulus were especially worked cooperatively with the years,” said Quigley. effective.” Burns and Vale Districts of the Bureau of Land Management, to determine the responses of cow- For more information about the “The use of 'unlock zones’ is one calf pairs to the eartag technology. electronic eartags, contact Art of the changes we feel very Tiedemann or Tom Quigley at the positive about,” said Quigley. “It Forestry and Range Sciences allows the animals to train them¬ Laboratory, 1401 Gekeler Lane, La selves. Our training period won’t Grande, Oregon 97850. need to be as long in the future." What’s next on the research agenda? “We need to make the eartag unit smaller, lighter, and more durable," said Quigley. "The technology is available. It's a matter of investing in engineering design so that the pieces fit together correctly.” The goal is to ultimately reduce the weight of the eartag to about an ounce, and to employ a battery that will last through one grazing season (about 6 months). The eartag must also be able to survive being chewed on and getting banged up on water troughs and fence posts. 6

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