There are also many anatomical and physiological means of coping with desert conditions. The silky flycatcher ( Phainopepla nitens) is a bird that lays its eggs and raises its young beginning in later winter (February) when its host plant desert mistletoe ( Chu and Walsberg, 1999) flowers and attracts nitrogen rich insects to feed its young, then they all leave the desert during the summer. The desert slender salamander ( Batrachoseps major aridus) is active only during wet winter periods, and otherwise very difficult to find ( Duncan and Esque, 1986). Mohave ground squirrels are active during a very short period of time during April through June each year, when they glean all of their nutritional needs, and reproduce ( Best, 1995). Desert tortoises vary their daily activity periods according to temperature windows that meet their physiological limits ( Zimmerman et al., 1994). Many desert animals avoid extremes of heat or cold by avoiding those conditions in subterranean or vegetative cover sites, and only being active for relatively short periods of time on a daily, seasonal, or annual basis. Mojave desert species are renowned for the variety of ways that they adapt to the harsh environmental conditions found there. Esque, in Encyclopedia of the World's Biomes, 2020 Mojave Desert Fauna The technique is now best used in analysis of multiple-tag recapture studies under models M B and M BH of Otis et al. Changing public perspectives and animal care policies have redefined when constant-effort removal methods are appropriate. Removal trapping has also been used in conjunction with pit-fall studies of herptiles ( Tilley 1982). In the past, removal trapping was commonly used in the study of small mammal populations ( Davis 1957, Kikkawa 1964), which can quickly replenish themselves. Animal control can be implemented while estimating both the initial and residual abundance of the population. Pest species are the best candidates for removal studies. The procedure of studying a population through the process of its demise by removal trapping limits the applicability of the method to select populations. The key to the generalized removal model is estimating abundance of animals in these later periods when vulnerability is more homogeneous between individuals and over time. Animals in greater contact with the trapping gear are more likely to be caught in the first one or few periods of a removal study, leaving less vulnerable individuals to be caught in later periods of the study. 9.108) is an attempt to cope with the problem that some animals are more vulnerable to capture than are others. Heterogeneity in the individual vulnerability of animals can effectively change the vulnerability coefficient over time. For instance, changes in moon phase can result in dramatic changes in the behavior of pocket mice ( Perognathus spp.) and kangaroo rats ( Dipodomys spp.), where predation by owls is enhanced in moonlit nights. Even then, subtle environmental changes can induce changes in animal behavior. The timing of the removal study should therefore be planned with weather forecasts in mind. This assumption can be violated if weather factors, which influence animal behavior, are not constant during the k -removal periods. 9.91) also assumes the vulnerability or catch coefficient ( c) is constant across sampling periods. Instead the catch data will need to be purposefully collected under experimental conditions. This precludes use of the constant-effort model in the analysis of traditional harvest data. Only under controlled conditions will effort likely be held constant. 9.97) is a special case of the variable-effort model ( Eq. Millspaugh, in Wildlife Demography, 2005 Discussion of Utility For small mammals, only species with enough detections to determine directional response are reported. Studies cited include unburned areas compared with severely burned areas with no postfire logging they exclude prescribed burns. 2010, Borchert 2012, Hanson 2013 4 Ungulate citations: Taber and Dasmann 1957, McCulloch 1969, Bendell 1974, Peek 1974, Davis 1977, Keay and Peek 1980, Smith 2000, Holl et al. 1996, McLellan and Hovey 2001, Cunningham and Ballard 2004, Cunningham et al. 2014 3 Carnivore citations: Paragi et al. 2012, Borchert and Borchert 2013, Letnic et al. 2006, Zwolak and Forsman 2007, Zwolak and Forsman 2008, Vamstad and Rotenberry 2010, Brehme et al. 2 Small mammal citations: Keith and Surrendi 1971, Cook 1959, Wirtz 1977, West 1982, Price and Waser 1984, Torre and Díaz 2004, Converse et al. Bats are categorized by phonic groups: of 6 phonic groups in 3 studies, 5 phonic groups showed positive response and 1 showed neutral response. 1 Bat citations: Schwab 2006, Malison and Baxter 2010, Buchalski et al.
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