I. Overview of a Few Concepts in Species Monitoring and Biodiversity Conservation.

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1 I. Overview of a Few Concepts in Species Monitoring and Biodiversity Conservation. A. Basic problem. Biological populations are facing continual and increasing threats posed by human population growth and development. Populations and species are being extirpated at an alarming rate worldwide. Monitoring the status and assessing the viability of all species is impossible. How do we decide what to monitor and study to help us reduce the rate of biodiversity loss? B. Focal species concept. Focal species include a wide variety of species categories, the key characteristic of focal species being that their status and time trend provide insights to the integrity of the larger ecological system (Committee of Scientists 1999). Focal species categories include: Indicator species: discussed below. Species of concern: species that may not necessarily provide information on the larger ecosystem, but because of their rarity or population threats will be monitored and assessed for viability. Keystone species: species whose effects on ecosystem structure or function are much greater than would be predicted from their abundance or biomass. 1

2 Ecological engineers: species that substantially alter their habitat thus altering the habitat for many other species (overlap with keystone species). Umbrella species: species that because of their large area requirements or use of multiple habitats, encompass the habitat requirements of many other species. II. Indicator Species. A. Definition of Indicator Species....an organism whose characteristics (e.g., presence or absence, population density, dispersion, reproductive success) are used as an index of attributes too difficult, inconvenient, or expensive to measure for other species or environmental conditions of interest. (Landres et al. 1988) B. Types of Indicator Species. Species whose status is believed to be indicative of the status of a larger functional group of species. Species whose status is believed to be reflective of the status of a key habitat type. Species whose status is believed to serve as an early warning of stressors to ecological integrity. 2

3 C. Potential problems associated with the use of Indicator Species. Population abundance is the most commonly used measure of a species status, and abundance (density) can be a misleading indicator of habitat quality, especially for species that use different habitats seasonally, species whose populations go through periodic fluctuations, species whose social status influence habitat use, etc. Each species possesses a unique array of life-history characteristics and thus responds to its environment in a unique way, making it difficult to assume that a change in population characteristics of one species is an indicator of changes in population characteristics of other species. Given the extreme complexity of natural systems, the probability is small that a single species could serve as an index of structure and functioning of a community or ecosystem. 3

4 Criteria for selecting indicator species are often confounded. For example, certain species of Neotropical songbirds are relatively easy to monitor and closely associated with particular vegetation communities (e.g., Brewer s sparrow for sagebrush communities), suggesting they may be good candidates for monitoring as an indicator species. However, the fact that they spend a significant portion of their lives in a different geographic area suggests that their population levels may not be good indicators of habitat conditions on their breeding range. Practical problems of accurately yet cost effectively estimating population abundance or other population measures. III. Management Indicator Species (MIS) and the Forest Service. A. Background. The Forest Service MIS concept is closely associated with the agency s regulatory requirement under the 1976 National Forest Management Act to...provide for diversity of plant and animal communities... 4

5 B. Forest Service regulatory language on MIS. In order to estimate the effects of each alternative on fish and wildlife populations, certain vertebrate and/or invertebrate species present in the area shall be identified and selected as management indicator species and the reasons for their selection will be stated. These species shall be selected because their population changes are believed to indicate the effects of management activities. Select management indicators for a forest plan or project that best represent the issues, concerns, and opportunities to support recovery of Federally-listed species, provide continued viability of sensitive species, and enhance management of wildlife and fish for commercial, recreational, scientific, subsistence, or aesthetic values or uses. Population trends of the management indicator species will be monitored and relationships to habitat changes determined. C. Examples of different MIS. Dixie National Forest: Utah prairie dog, bald eagle, peregrine falcon, elk, mule deer, wild turkey, goshawk, yellow-breasted chat, southwest willow flycatcher, Mexican spotted owl, etc. 5

6 Fishlake National Forest: elk, mule deer, goshawk, sagebrush nesters (sage thrasher, vesper sparrow, sage sparrow), riparian guild (McGillivray s warbler, Bullock s oriole, water pipit), cavity nesters (Williamson s sapsucker, bluebirds, hairy woodpecker), resident trout. Bridger-Teton National Forest: peregrine falcon, grizzly bear, bald eagle, whooping crane, moose, mule deer, elk, bighorn sheep, pronghorn, American marten, Brewer s sparrow, etc. Uinta National Forest: American beaver, goshawk, three-toed woodpecker, Colorado River and Bonneville cutthroat trout. Wasatch-Cache National Forest: American beaver, goshawk, snowshoe hare. D. Legal background. In the past, the Forest Service has relied heavily on habitat condition and inventory rather than direct monitoring of MIS populations (i.e., the Forest Service has used habitat surveys as a proxy for population surveys). Earlier court rulings supported the Forest Service s position (e.g., Inland Empire v. Forest Service 1996, Idaho Sporting Congress v. Thomas 1998). 6

7 However, recent court rulings have gone against the Forest Service and have required the agency to adhere to its own regulatory language directing Forests to monitor population trends of Management Indicator Species (e.g., Sierra Club v. Martin 1999, Utah Environmental Congress and Forest Guardians v. Zieroth 2002, Neighbors of Cuddy Mountain v. Giles 2002). E. Changing regulatory direction. Current regulatory direction related to Management Indicator Species, biodiversity, and population viability comes from the 1982 Forest Planning Regulations (36 CFR 219). Finally, during the late 1990s the outdated 1982 Forest Planning Regulations were revised. The revised Forest Planning Regulations were printed in the Federal Register in The 2000 Forest Planning Regulations adopted the focal species monitoring concept recommended by the Committee of Scientists (1999). 7

8 Before they were ever implemented, the 2000 Regulations were suspended by the Bush administration in After suspending the 2000 Regulations, a new set of Forest Planning Regulations was developed. A draft version of the revised Regulations was printed in the Federal Register in 2002, but a final version of the revised Regulations has yet to be adopted. The current version of the revised Forest Planning Regulations has no requirements to monitor Management Indicator Species. IV. Management Indicator Species Example: the American Beaver on the Uinta National Forest. 8