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Habitat analysis is strictly defined as a statistical examination to identify the environmental variables that a species associates with, wherein association is taken as some form of correspondence between a species response variable (e.g., presence–absence or abundance) and the environmental variables. There are other statistical techniques and empirical goals that extend this basic framework. These techniques often rely on a habitat analysis having been conducted as an initial step. Resource selection functions quantify an individual’s and a species’ use of a resource based upon the properties of the resource. Resource is broadly defined and can include particular types of habitat. Selectivity and preference indices are used to assess an individual’s preference and active choice of different resource types. Compositional data analysis is a statistical method for examining the composition of an individual’s territory or home range with regard to different habitat types that may be represented. Habitat suitability modeling and species distribution modeling are closely related techniques designed to map the spatial distribution of a species’ habitat and sometimes the species itself based upon its habitat requirements and other factors.

Habitat fragmentation results in the reduction and isolation of amphibian populations and the subsequent increased risk of local extinction. While local extinctions are often part of amphibian population dynamics, amphibian populations persist because such extirpations are compensated for by recolonization and the resulting rescue effect. However, the fragmentation of amphibian habitats inhibits dispersal and thereby hinders or prevents the rescue effect. Massachusetts provides a prime example of this conservation challenge and of the need to protect connected habitat complexes for amphibians, especially for migratory salamanders. An effective strategy for statewide conservation of ambystomatids involves proactive protection of habitats, rather than solely relying on regulations. Initially, the effectiveness of habitat reserves and the process of designing them may be limited by a lack of empirical data to guide efforts. Due to limited information on upland habitat use and dispersal distances of these animals, there is a certain degree of uncertainty in designing reserves for ambystomatids.

This chapter focuses on the Costa Rican dry-forest avifauna. It discusses the origin, distribution, habitat use, migration behavior, reproduction, and the adaptation of dry-forest birds to seasonal changes in food abundance. It also presents recommendations for their protection and conservation.

This chapter discusses the various aspects of the environment that are important to anoles, as well as the extent to which habitat use shifts through time. Anoles occur in many habitats, elevations, and latitudes, and differ in extent of basking. There are aspects of the environment that vary within and among localities, and to which anoles specialize. This specialization allows anole species to adapt to extreme habitats, and permits sympatric species to coexist while occupying the same structural microhabitat. The chapter discusses two important environmental factors—temperature and moisture—and then examines the effectiveness of microhabitat selection for anole thermoregulation. It also describes remote sensing approaches to investigate the habitat requirements of anoles and ontogenetic and seasonal shifts in habitat use.

This chapter initiates a multiyear survey of bats in the reserve and the adjacent Refugio de Vida Silvestre Cueva Los Murciélagos to quantify species diversity, abundances, habitat use, seasonality, and reproduction. It addresses the following questions in surveying bats during five rainy seasons and four dry seasons from July 1999 through February 2006: Which species of bats are present in the area? Are the bat communities the same in three different habitats—coastal/inland forest, and limestone caves? Are the species diversity and abundances of bats in the rainy season similar to those in the dry season? Can seasonal patterns of reproduction be discerned? Are the species diversity and abundances of bats at Cabo Blanco (a tropical moist forest in the Holdridge Life Zone classification) similar to those in the nearly tropical dry forest at Parque Nacional Palo Verde? What are the conservation implications of the bat assemblages found in the regenerating forest?

Individual ranging patterns and demographic performance of elephants are both strongly influenced by foraging location and success. This chapter describes a study of the time spent feeding and the use of habitats in the Amboseli basin by adult female and male elephants during two years in the mid-1980s (1982–84) in relation to changes across the seasons. Choices between the broad food classes of grass and woody browse are examined in light of the contrasting plant abundance available in a year with higher than average rainfall and in a drought year, as well as differences between the sexes. Estimated intake of two critical nutrients, digestible energy and protein, are compared with calculated requirements for maintaining body condition and investing in offspring.

This study examined the relationship between the Conservation Reserve Program (CRP) lands and Greater Sage-Grouse (Centrocercus urophasianus) in Washington state including an assessment of population change, nest-site selection, and general habitat use. Nest-site selection of eighty-nine female sage-grouse was monitored between 1992 and 1997 with the aid of radiotelemetry. The proportion of nests in CRP lands significantly increased from 31% in 1992–1994 to 50% in 1995–1997, although more nests were detected in shrub steppe (59% vs. 41% of 202 nests). The increase appeared to be associated with maturation of CRP fields, which were characterized by increased cover of perennial grass and big sagebrush (Artemisia tridentata). Nest success was similar for nests placed in the two cover types. Analysis of male lek attendance prior to implementation of CRP (1970–1988) illustrated similar rates of population declines in two separate groups of sage-grouse in north-central and south-central Washington. Data from 1992 to 2007 following establishment of the CRP revealed a reversal of the population decline in north-central Washington while the south-central population continued a long-term decline.

This chapter focuses on the postbreeding period in the avian migrant's annual cycle. It first discusses the five principal purposes for the postbreeding period: conduct of the prebasic molt; exploratory movements by juveniles to familiarize themselves with location of feeding and potential breeding areas; prospecting movements by adults anticipatory of the next breeding season; preparation for departure on fall migration; and optimization of feeding strategies to limit predation while engaged in other postbreeding activities. It then considers migratory birds' movements and habitat use during the postbreeding period, along with the duration of their postbreeding period. It also examines the timing and siting of the prebasic molt in relation to other major events in the migrants' life cycle.

South Dakota, a state that lies in the prairie pothole region, is bisected into two nearly equal eastern and western segments by the upper Missouri River. Despite a 45% decline in wetland numbers in eastern South Dakota, more than 930,000 wetland basins remain. While concern about amphibian population declines have produced conservation initiatives in other Midwestern states, in South Dakota such programs have not been implemented and there remains a lack of basic knowledge concerning the distribution and habitat use of South Dakota frogs, toads, and salamanders. To address this lack of data on South Dakota anurans, this chapter presents distribution maps for twelve species of frogs and toads. These maps include new records from fieldwork conducted in 1997–1998, where 1,496 wetland sites throughout all forty-four counties in eastern South Dakota were surveyed. The distribution maps were constructed using historical data from the South Dakota Natural Heritage Database. The chapter also explores how breeding anurans use habitats throughout eastern South Dakota by using occurrence rates of eleven species in seven different types of wetlands.

Game releases for conservation could share problems and possible solutions with wildlife reintroductions, as could be the case with the iconic gamebird of conservation concern, the grey partridge. This chapter details research that addresses the common problem of behavioural deficiencies in captive-bred animals and applies it to this widely released but unsuccessfully reintroduced bird. This study showed that released, captive-bred grey partridges used habitats, performed vigilance for predators, and were feeding and roosting in ways that probably made them more vulnerable to predators. The possibility of predicting the survival of individual grey partridges based on their temperament in the bold–shy continuum was tested for, but results on this were not conclusive. Overall, it showed how the scientific framework of wildlife reintroductions can be applied to a gamebird to successfully show weaknesses in their behaviour and to suggest possible improvements in their rearing methods.