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As what was learned from Chapter 6, studies that compare older sampling techniques to newer ones sometimes are necessary to advance the science of plant ecology. This chapter presents another comparison of techniques to challenge very commonly used rangeland sampling techniques. In terms of measuring and monitoring native and non-native plant species richness in grassland habitats, never has such a study been so urgently needed. The inertia of rangeland sampling techniques is extremely apparent in the literature.

This chapter looks at sampling techniques and setting thresholds. The cornerstone of any integrated insect management regime is accurately identifying pest insects (including assessing population density) and developing appropriate action thresholds. Various methods have evolved by which the populations of insects present in the turf environment may be determined relatively rapidly and efficiently. These methods have become standard techniques for reporting insect densities. The chapter differentiates between passive sampling techniques (use of traps) and active visual inspection techniques (actual quantification of insect populations). Thresholds in turf integrated pest management usually are more accurately considered tolerance levels, or action thresholds. The tolerance level, or action threshold, for turfgrass insects is site-specific and depends on many factors.

Recent evidence of worldwide amphibian population declines has highlighted the need for a better understanding of both species-specific habitat associations and methodologies for monitoring long-term population trends. For decades, studies have relied on relative abundance indices to evaluate salamander populations across space and time. However, little effort has been made to evaluate the underlying assumptions of these indices or their relationship to the true population. Great Smoky Mountains National Park (GRSM) is committed to incorporating salamander population monitoring into the park's long-term inventory and monitoring program based on evidence that salamanders are finely tuned indicators of environmental quality. Data from ongoing research in GRSM designed to assess spatial and temporal patterns in salamander diversity and abundance are being used to evaluate sampling effectiveness and bias across a variety of habitats. This chapter presents evidence that some common salamander sampling techniques may not be appropriate indices for salamander abundance and, therefore, may not be suitable methodologies for use in long-term monitoring programs in the southern Appalachians and perhaps elsewhere.

This chapter discusses the major topics one needs to know about within-group primate behaviour research. It begins by defining the primate group and reviewing the array of social units identified. Primate groups can be described in terms of their social organization, mating system, and social structure; these attributes are discussed, along with group size, cohesion, sex ratios, and costs-benefits of group living. The habituation process, which can vary from a few months to a year or more depending on species and group history, is reviewed. This is followed by a discussion of standard sampling techniques for behavioural data. The authors explore several key within-group attributes including activity budgets, foraging behaviour, competition, aggression, and cooperation. Geographic Information Systems (GIS) is an invaluable tool for with-group behaviour studies, and the authors review the various ways it has been used. Social network analysis is a relatively new approach in primate behavioural studies with great potential. The chapter concludes with the contributions that behavioural studies can make to primate conservation.

This chapter reviews traditional and new zooplankton sampling techniques, sample preservation, and sample analysis, and provides the sources where in-depth discussion of these topics is addressed. The net systems that have been developed over the past 100+ years, many of which are still in use today, can be categorized into eight groups: non-opening/closing nets, simple opening/closing nets, high-speed samplers, neuston samplers, planktobenthos plankton nets, closing cod-end samplers, multiple net systems, and moored plankton collection systems. Methods of sample preservation include preservation for sample enumeration and taxonomic morphological analysis, and preservation of samples for genetic analysis. Methods of analysis of zooplankton samples include determination of biomass, taxonomic composition, and size by traditional methods; and genetic analysis of zooplankton samples.

This chapter reviews phytoplankton sampling and analysis techniques, discussing them in light of their advantages and disadvantages. Different sampling methods have varying levels of precision and accuracy. This means that they affect the ways in which individual data sets can be interpreted, and methods therefore have to be kept consistent within time series to avoid creating artefacts. The discussions cover qualitative and semi-quantitative methods, quantitative methods, sample analysis, automated/semi-automated systems, and molecular methodologies. None of the methods are universally applicable but depend on the right set of tools and the scientific and financial context in which they are used. Molecular techniques hold great promise particularly for taxa that cannot be identified by routine microscopical techniques.