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Site Choice (site + choice)
Selected AbstractsConspecifics and Their Posture Influence Site Choice and Oviposition in the Damselfly Argia moestaETHOLOGY, Issue 8 2009Catherine J. Byers Finding a suitable oviposition site can be costly because of energy and time requirements, and ovipositioning can be dangerous because of the risk of predation and harassment by males. The damselfly Argia moesta oviposits, contact-guarded by her mate, on vegetation in streams. Oviposition aggregations are commonly observed in this species, despite their territorial nature during other behaviors. We conducted experiments in the field to test the hypothesis that aggregations are the result of conspecific attraction. In the first experiment, two oviposition sites (sycamore leaves) were provided, one with models of ovipositing pairs, and one without. In the second experiment, one leaf again had ovipositing models, while the other had models of uncoupled males and females in a resting posture. In both experiments, damselfly pairs preferred the site with ovipositing models. In general, they visited the ovipositing models first more often than expected by chance, stayed longer there, were more likely to oviposit there, and laid a greater total number of eggs there. These results support the hypothesis that conspecific attraction is responsible for ovipositing aggregations in A. moesta and that posture is an important cue for attraction. Using conspecific cues could be a beneficial strategy to save in search costs while taking advantage of the presence of ovipositing conspecifics to dilute the effects of harassment and predation. [source] Common use of sleeping sites by two primate species in Tana River, KenyaAFRICAN JOURNAL OF ECOLOGY, Issue 1 2001Geoffrey M. Wahungu Abstract Choice of sleeping sites by two species of primates sharing two adjacent patches of gallery forest in Tana River, Kenya, was studied between August 1992 and February 1993. One group each of the Tana crested mangabey, Cercocebus galeritus galeritus Peters, and yellow baboon, Papio cynocephalus cynocephalus L., interchangeably shared nine sleeping sites distributed among four tree species, Acacia robusta Burch., Ficus sycomorus L., Abizzia gummifera (J. F. Gmel.) E. A. Sm. and Pachystela msolo (Engl.) Engl. The trees used by both species as sleeping sites were mainly tall trees with canopy level or emergent crowns. The trees had relatively larger crowns and lower percentage canopy cover compared to other trees at the site and were characterized by poor to moderate accessibility. Overlap in use of sleeping sites was never simultaneous and baboons occasionally supplanted mangabeys. Site choice by these two primates appeared to be influenced by predation risk, the feeding area used in the late afternoon, daily range and the availability of trees with the preferred structural characteristics. Sleeping sites appeared to be limited during and immediately after the wet season, when the frequency of supplantings increased. This observation is attributed to an increase in percentage canopy cover. Résumé Entre août 92 et février 93, on a étudié le choix des lieux de sommeil par des primates qui partageaient deux portions adjacentes de la galerie forestière de la rivière Tana, au Kenya. Un groupe de cercocèbes à crête, Cercocebus galeritus galeritus Peters, et un de babouins olive, Papio cynocephalus cynocephalus L., partageaient pour y dormir, de façon interchangeable, neuf emplacements répartis parmi quatre espèces d'arbres, Acacia robusta Burch., Ficus sycomorus L., Abizzia gummifera (J.F. Gmel) E.A. Sm. Et Pachystela msolo (Engl) Engl. Les arbres qui servent aux deux espèces comme sites de sommeil étaient principalement des arbres élevés, avec une canopée ou une couronne émergentes. Les arbres avaient une couronne relativement plus large et une couverture de la canopée dont le pourcentage était relativement plus bas que celui des autres arbres de l'endroit, et ils se caractérisaient par une accessibilité médiocre à modérée. Le recouvrement entre les sites de sommeil n'étaient jamais simultanés, et à l'occasion, les babouins supplantaient les cercocèbes. Le choix des sites par ces deux primates semblait influencé par les risques de prédation, par l'aire de nourrissage fréquentée en fin d'après midi, par le déplacement de la journée et par la disponibilité d'arbres qui présentaient les caractéristiques structurelles souhaitées. Les sites de sommeil semblent être limités à la saison des pluies et juste après, lorsque la fréquence d'évictions augmentait. Cette observation a été attribuée à une augmentation du pourcentage du couvert de la canopée. [source] COMPENSATORY RESTORATION IN A RANDOM UTILITY MODEL OF RECREATION DEMANDCONTEMPORARY ECONOMIC POLICY, Issue 4 2010GEORGE R. PARSONS Natural Resource Damage Assessment cases often call for compensation in non-monetary or restoration equivalent terms. In this article, we present an approach that uses a conventional economic model, a travel cost random utility model of site choice, to determine compensatory restoration equivalents for hypothetical beach closures on the Gulf Coast of Texas. Our focus is on closures of beaches on the Padre Island National Seashore and compensation for day-trip users. We identify restoration projects that compensate for beach closures and that have good alignment in terms of compensating those who actually suffer from the closures. (JEL Q26) [source] Oviposition Preferences in Newts: Does Temperature Matter?ETHOLOGY, Issue 6 2009Jan Dvo A female's decision where and when to place her eggs has important fitness consequences for her offspring. Although temperature is considered among the most relevant abiotic factors affecting female oviposition site choice in ectotherms, little is known about the relative importance of temperature cues in complex oviposition decisions. In this study, we examined female's oviposition choice under conflicting demands for temperature and embryo protection by studying oviposition behaviour in female alpine newts, Triturus alpestris, exposed to various thermal conditions and the availability of egg-wrapping vegetation. Females oviposited between 12.5 and 22.5°C in the aquatic thermal gradient (5,32.5°C) with the unrestricted availability of oviposition vegetation. The removal of the vegetation from predominantly chosen oviposition temperatures (15,20°C) induced egg-retention in most females. This suggests that both temperature and the presence of egg-wrapping vegetation play important roles in oviposition site choice of alpine newts. [source] Tree and forest characteristics influence sleeping site choice by golden lion tamarinsAMERICAN JOURNAL OF PRIMATOLOGY, Issue 9 2007Sarah J. Hankerson Abstract Lion tamarin monkeys are among a small number of primates that repeatedly use a few tree holes for the majority of their sleeping sites. To better understand why lion tamarins rely on tree holes as sleeping sites, we compared the physical characteristics of frequently used sleeping sites, infrequently used sleeping sites, and randomly selected forest locations at multiple spatial scales. From 1990 to 2004, we recorded 5,235 occurrences of sleeping site use by 10 groups of golden lion tamarins (Leontopithecus rosalia) in Poço das Antas Reserve, Rio de Janeiro State, Brazil. Of those, 63.6% were tree holes. Bamboo accounted for an additional 17.5% of observations. Frequently used tree holes were more likely to be found in living trees and their entrances were at lower canopy heights than infrequently used tree holes. We also found that frequently used sleeping sites, in comparison to random sites, were more likely to be found on hillsides, be close to other large trees, have a lower percent of canopy cover, and have larger diameter at breast height. Topography and small-scale variables were more accurate than were habitat-level classifications in predicting frequently used sleeping sites. There are ample tree holes available to these lion tamarins but few preferred sites to which they return repeatedly. The lion tamarins find these preferred sites wherever they occur including in mature forest and in relics of older forest embedded in a matrix of secondary forest. Am. J. Primatol. 69:976,988, 2007. © 2007 Wiley-Liss, Inc. [source] Superficial lizards in cold climates: Nest site choice along an elevational gradientAUSTRAL ECOLOGY, Issue 7 2009J. SEAN DOODY Abstract Embryonic conditions may limit the distributions of egg-laying ectotherms, and recent research suggests that nesting mothers of wide-ranging species may use a number of factors to compensate for differing climates. However, while variation in temporal factors across environmental gradients are common or pervasive (i.e. seasonal timing of nesting), similar evidence for spatial factors is rare (e.g. aspect, openness and depth of nest sites). I tested the idea that a wide-ranging lizard, the Australia water dragon (Physignathus lesueurii), uses nest depth to counter climate differences along a temperature cline at their cold-end range margin. Two measures of nest depth were significantly, inversely related to elevation across six populations spanning 700 m. Elevation explained 83,86% of the variation in nest depth. These findings support a thermal compensatory mechanism for this pattern, although soil moisture compensation is plausible. My results directly support a recent, untested prediction that the evolution of viviparity in reptiles is preceded by a behavioural shift towards increasingly superficial nest sites in cold climates, followed by selection for increased egg retention to avoid temperature extremes. However, in the present study egg desiccation rates increased with increasing elevation in a dry year, suggesting that increased egg retention may evolve in response to lethal hydric conditions, rather than lethal temperatures. When considered alongside recent research, the present study indicates that water dragons possess several mechanisms for adjusting to climate change. [source] | ||||||||||