Historic, Archive Document Do not assume content reflects current scientific knowledge, policies, or practices. United States Department of Agriculture Forest Service September 1983 West 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 Agriculture In This Issue page Monitoring wildlife by whole-guild inventories 1 Experiment at San Antonio Mountain 5 Researchers optimistic about control of laminated root rot 8 The liquidator of lodgepole pine 1 1 New publications 16 Cover Research wildlife biologists at the Pacific Southwest Station believe that a new approach — inventorying everything in a wildlife guild (a group of species that exploits the same class of environmental resources in a similar way) — might be a more efficient and less costly way of evaluating wildlife and wildlife habitat. The birds on the front cover are just a few of the many being studied. Read more about it on page 1 . To Order Publications Single copies of publications re¬ ferred to in this magazine are avail¬ able without charge from the issuing station unless another source is in¬ dicated. See page 19 for ordering cards. Each station compiles periodic lists of new publications. To get on the mailing list, write to the director at each station. To change address, notify the magazine as early as possible. Send mailing label from this magazine and new address. Don’t forget to include your Zip Code. Permission to reprint articles is not required, but credit should be given to the Forest Service, U.S. D A. Mention of commercial products is for information only. No endorsement by the U.S. D A. is implied. Forestry Research West Western Forest Experiment Stations Pacific Northwest Forest and Range Experiment Station (PNW) 809 N.E. 6th Ave. Portland, Oregon 97232 Pacific Southwest Forest and Range Experiment Station (PSW) P.O. Box 245 Berkeley, California 94701 Intermountain Forest and Range Experiment Station (INT) 507 25th Street Ogden, Utah 84401 Rocky Mountain Forest and Range Experiment Station (RM) 240 West Prospect Street Fort Collins, Colorado 80526 Monitoring wild¬ life by whole- guild inventories by Dennis G. Hanson Dennis G. Hanson is a free¬ lance writer who specializes in natural resources. He lives in Sebastopol, California. The guild-unit approach was studied on the San Joaquin Experimental Range, Madera County, California. The plots were mature woodlands of mixed stands of blue oak, in¬ terior live oak, and digger pine, with a shrub layer of Buck brush, and ground cover of annual grasses and forbs. The National Forest Management Act of 1976 (NFMA) requires that all wildlife resources on National Forests be monitored by means that are not only comprehensive but also biologically and statistically sound. Attempting to met the NFMA re¬ quirements by classical methods of sampling animal populations, coupled with standard methods of statistical analysis, would be prohibi¬ tively expensive. Jared Verner, research wildlife biologist at the PSW Station, believes that a new approach — inventorying everything in a wildlife guild — “a group of species that exploits the same class of environ¬ mental resources in a similar way” — might be a more efficient and less costly way of evaluating wildlife and wildlife habitat. The very term itself, “guild,” has odd beginnings. In Anglo-Saxon days, a “gild” was a penitent offer¬ ing, a protection against the future. A few centuries later, medieval merchants and tradesmen foresaw their own needs for collective pro¬ tection. Binding themselves together with common wants and goals, their “guilds” were forerunners of today’s trade unions. Here the term is used to denote the ecological mergers that biologists apply to nature’s world of common interests, a group of plants or animals that somehow have an ecological kindredship and similar mode of life. Depending on what is needed, wild¬ life researchers can define a guild to their own investigative liking. For instance, in one study the species may be foliage-gleaning insects, because they use a similar food in a shared environment. Other studies may have species that have diet or breeding similarities in a certain ecosystem, such as the shrub layer in a woodland ecosystem. The indicator-species method is per¬ haps the most widely used method of guild research today. The conjec¬ ture is that since all members of a certain guild use the same re¬ sources — air, water, food, breeding space, nesting area — all should respond similarly to certain changes in their environment. In other words, pick a certain bird in a given guild and it can theoretically tell the researcher what’s happening with the rest of the creatures in that same habitat. If its status changes for better or worse, there should be good scientific reason that the status of the entire guild is similarly changing. A whole-guild approach For a multitude of reasons, Verner, who is in charge of the Pacific Southwest Station’s research on Protection and Management of Sensitive Species in California, thinks that a whole-guild approach to define habitat capability to sup¬ port wildlife populations could prove much more efficient — and money saving — than the use of single in¬ dicators. It would look at all the species in a given guild. One support for his approach is that guilds can be grouped in a number of ways, depending on management needs, such as all species that use a particular environment for breed¬ ing, or all species that depend on tree canopies for foraging, or use tree boles for nesting. There are other advantages. “When using the indicator-species method,” said Verner, “you can’t get a high count of all the species in that par¬ ticular environment. You also have to assume, perhaps falsely, that the species you pick is a true indicator for the area.” For example, if one were using the indicator method to study a certain riparian area, the red-tailed hawk might be selected as the keystone to determine the health of the habitat. As the red-tailed hawk went, so, one might extrapolate, went the health of that habitat. But is it cer¬ tain that the red-tailed hawk is the best indicator of the health of that area? Regardless of what happens to the hawk’s population, are there other, more subtle elements that im¬ pact the vitality of the riparian zone? “If a guild includes bark and canopy feeders, all species should respond similarly to timber harvest, but not necessarily to a fire. The timber harvest would generally lower population levels of species dependent upon trees, either the canopies or the boles. But a fire of moderate intensity might reduce tree canopy without markedly dimini¬ shing the bark surface. So, at least for a short time, canopy feeders could be eliminated by a fire when bark feeders were not,” Verner said. One must also be careful about the way guilds are composed says Verner. For example, “the road- runner, a ground feeder in arid shrublands of the Southwest, is an unlikely guild companion with the wood ibis, a swamp-dwelling species of the southern states that feeds in shallow freshwater ponds and sloughs. In one guild, gleaners of insects in trees and shrubs were combined, but some environmental changes effect the shrub and tree layers differently.” Guild cell from matrix for canopy feeders: (clockwise, top left) Acorn woodpecker (ACWO), Ash-throated flycatcher (ATFL), Plain titmouse (PLTI), Western bluebird (WEBL). Four-letter legend in parentheses identifies species on matrix. Saving dollars Another advantage for the whole- guild approach may be cost. Using the indicator method, the number of species counts needed to detect meaningful annual differences can be both prohibitively large and ex¬ pensive, even for common species. For example, with an average of one bird per count, one needs 12,300 counts to detect a 10 percent difference in abundance of that species between years. In one such case that Verner cites as an example, the salary alone for entry- level technicians to do the job would be $33,840 per year. Verner’s whole-guild proposal, which would count all species in any guild, is a fresh approach. “There has been some research, and a lot of us have thought about it for a long time,” said Verner, “but it’s never actually been applied.” By counting everything in the defined guild, the approach reduces the possibility of losing a species from the area. It would also permit a researcher to look separately at any trends among permanent residents, winter residents, migrant breeders, and spring or fall resi¬ dents. For instance, if timber Ash-throated Flycatcher Starling harvesting or a hard winter wipes out a resident breeder, it would show up in the whole-guild evalua¬ tion. It might not, however, if only one indicator bird was being exam¬ ined. Looking at all species within a given area might also give a re¬ searcher a feel for whether changes were due to habitat impact or some¬ thing else. At present, officials of the Sierra National Forest in California are gearing up to use the whole-guild approach in their land-management programs, particularly in three major habitat areas — riparian, meadow- PSW Guild cell from matrix for ground feeders: (clockwise, top left) American kestrel (AMKE), Screech owl (SCOW), Common flicker (COFL), Starling (STAR). Four letter legend in parentheses identifies species on matrix. edge, and late successional mixed conifer. The plan for monitoring wildlife re¬ sources was recommended by the Interdisciplinary Planning Team of the Sierra National Forest. Verner considers the plan as reasonable and realistic. “It recognizes the need to provide a biologically sensi¬ ble and statistically sound system that is cost-effective," Verner said. The plan calls for integrated moni¬ toring at three levels: 1) Species — only those management indicator species required by law; 2) Manage¬ ment guilds — guilds of birds in three habitats especially vulnerable to change by human activities; and 3) Habitats — most wildlife species will be monitored by inference from trends in habitats, based on know¬ ledge of each species’ habitat re¬ quirements. “The use of this plan by the Sierra National Forest gives us an oppor¬ tunity to test the system,” said Verner, “to see if it gives us the answers we’re after, as well as whether it saves money." Even though Verner calls the plan “sensible and reasonable," he says it may be far from the system that will eventually emerge as an ac¬ cepted standard for all National Forests. “Other Forests will try other systems, and rightly so," he says, “all systems should be studied care¬ fully to learn how well they meet the intent of NFMA, and all should have the flexibility to allow changes that promise to improve the quality of monitoring wildlife resources, at lower costs but without sacrificing quality.” The system is planned for a gradual phase-in by the Sierra National Forest. “They are already choosing the meadow-edge sites," said Verner. Sample results from that area study may not be seen for a year, while, at the same time, the other two study areas are being developed. “It takes time," said Verner. “At least 200 sites in each of the three types must be chosen, marked, and documented. Even if it’s being done full-time, it can take a full season just to locate the right sites in any habitat area.” After the study sites are picked, the research design has to be set — what time of day to observe, months and seasons of the year, and groups of species to be defined as a guild. Any chosen site is a single point where a trained observer may spend 5 to 10 minutes. “Tests will have to determine what the optimum length of time is, as well as the daily number of observations,” said Verner. The observations will be done by entry-level biological technicians or perhaps a staff of volunteers. “They'll have to be screened to make sure they can identify the species,” he said. Snags UJ z o N U z Q HI UJ u_ > cc < cc Q. 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