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201.
Many nocturnal katydids (Orthoptera: Tettigoniidae) produce intense calling songs, and some bat species use these songs to detect and locate prey. One Nearctic katydid species, Neoconocephalus ensiger, ceases or pauses singing in response to bat echolocation calls. We tested the hypothesis that song cessation is an effective defence against gleaning bats (i.e., bats that take prey from surfaces). We observed Myotis septentrionalis, a sympatric bat species that uses prey-generated sounds when gleaning, attack and feed on singing N. ensiger in an outdoor flight room. These bats demonstrated a preference for the calling song of N. ensiger over a novel cricket calling song when they were broadcast from a speaker in the flight room. Bats attacked speakers broadcasting N. ensiger calling song as long as the song was continuous and aborted their attack if the sound stopped as they approached, regardless of whether a katydid was present as a physical target on the speaker. Echolocation calls were recorded during attacks and no significant differences were found between continuous and interrupted song approaches for four call parameters, suggesting that M. septentrionalis may not use echolocation to locate silent prey. Therefore, song cessation by katydids in response to ultrasound is an effective defence against gleaning bats.  相似文献   
202.
Studies of innate colour preference and learning ability have focused on differences at the species level, rather than variation among populations of a single species. Initial strength and persistence of colour preferences are likely to affect colour choices of naïve flower visitors. We therefore study the influence of both the strength and persistence of innate colour preference (for blue) on an operant learning task (associating food reward with yellow flowers) in two populations of the bumblebee Bombus terrestris. We found that both strength and persistence of blue preference differed significantly between populations: B. terrestris dalmatinus had a weaker and less persistent blue preference than B. terrestris audax. These differences in preference also influenced learning performance. Considering only landing behaviours, one-trial learning occurred in the majority (73%) of bees, and was achieved sooner in B. terrestris dalmatinus because of its weaker blue preference. However, compared to landing behaviours the relative frequency of approach flights to rewarding and unrewarding flower types changed more slowly with task experience in both populations. When considering both approaches and landings, the rate of learning, following the first rewarded learning trial, was faster in B. terrestris audax than B. terrestris dalmatinus. However, the net effects of population differences in blue preference and learning dynamics result in similar final levels of task performance. Our results provide new evidence of behavioural differences among isolated populations within a single species, and raise intriguing questions about the ecological significance and adaptive nature of colour preference.  相似文献   
203.
Kleptoparasitism is a tactic used to acquire food opportunistically and has been shown to provide several benefits, including greater food intake rate and the acquisition of items not normally available during self-foraging. Host individuals may differ in their ability to defend themselves against kleptoparasitic attacks and therefore identifying those host individuals that are particularly vulnerable to attack could both provide energetic benefits and increase the efficiency of kleptoparasitism as a foraging strategy. Here, we show that the kleptoparasitic fork-tailed drongo (Dicrurus adsimilis) specifically targets juveniles when following groups of cooperatively breeding pied babblers (Turdoides bicolor). Drongos give alarm calls upon sighting a predator, thus providing extra predator vigilance to foraging pied babblers. However, drongos also use alarm calls to steal food items. During kleptoparasitic attacks, drongos give false alarm calls and then swoop down to steal food items dropped by alarmed babblers. Juvenile pied babblers are particularly vulnerable to attack because they (a) spend a longer period handling prey items prior to consumption and (b) respond to alarm calls primarily by immediately moving to cover, in contrast to adults who respond by looking up and visually scanning the surrounding area. Drongos attack juvenile babblers significantly more often than adults, with attacks on juveniles more likely to result in the successful procurement of a food item. This patterns of attack suggests that drongos are able to differentiate between individuals of different age when targeting pied babblers, thus increasing the efficiency of kleptoparasitism as a foraging strategy.  相似文献   
204.
The relationship between body mass and reactions speed in response to a predatory threat is poorly understood. Theory predicts that different vigilance patterns are optimal for the detection of different predator types. We suggest that birds of different individual state might also differ in their speed of response dependent upon predator type. We used laboratory trials of wild caught chaffinches (Fringilla coelebs) to determine how between individual differences in chaffinch behaviour and state correlate with latency to react to a ground predator model (domestic cat), thus providing a comparison with previous work in the same model system using aerial predator models. In experiment 1, we observed chaffinch responses to a moving cat model, simulating a stalking predator. In experiment 2, we used a camouflaged cat model simulating an ambush predator. Both experiments show evidence suggesting heavier individuals (which previous literature has linked to impaired flight performance) responded more quickly to the model cat. Heavier individuals also had shorter interscan intervals. In contrast to a previous study, both experiments found individuals with a higher intake rate were not faster at responding to the cat model. In addition, individuals in experiment 1 that head turned more while scanning were slower to respond to the stalking cat model. Our work suggests that although heavier individuals may have impaired escape performance they appear to show behavioural compensation by allocating more attention to anti-predator behaviour and by modifying their interscan intervals, resulting in faster response times to a ground predator. We suggest more experiments investigating response time to different predatory types and explicitly manipulating state to elucidate cause and effect.  相似文献   
205.
The increasing environmental awareness caused by the green movement has led to changes in attitude towards our traditionally wasteful society. Recent surveys in Hong Kong have shown that waste recycling has gained increasing verbal support among its citizens. This paper reports on recent findings which reveals that some discrepancies exist between people's attitude and behaviour towards waste recycling. The implication of this phenomenon on how and when a waste recycling policy should be carried out is considerable. Two major types of barriers to waste recycling and reduction were evident. Technical barriers to recycling included lack of appropriate information, lack of conveniently located bins and of temporary storage space, whilst the most critical barrier to paper waste recycling was the presence of non-recyclable materials in some paper items. Psychological barriers included the attitude of being troubled, and that too little waste was involved to be worth the effort. Technical barriers were found to dominate in commercial paper waste recycling, and can usually be overcome while psychological barriers were more significant in household waste recycling and are more difficult to solve. Thus, it might be concluded that, if a large scale household waste recycling programme were in place in Hong Kong, more effort should be devoted towards educating the public, to eliminate as many psychological barriers as possible. Findings from attitude surveys on recycling can provide valuable information for policy makers. However, a review of the literature indicates that findings from attitudinal and self-reported behavioural surveys may exaggerate the proportion of those who have a favourable attitude towards the surveyed subject matter. Thus, it is prudent for policy makers to consider the response rate of the surveys also.  相似文献   
206.
《Environmental Hazards》2013,12(4):340-357
Droughts occur as a natural feature of many climates. Several southern areas of the UK experienced water stress during 2004–2006 because of low water availability and high water demand. Climate change scenarios suggest that drought frequency could increase here in the future. This will increase the competition for water across all sectors. Understanding people's perceptions of drought and climate change is likely to be an important factor for sustainable water management by pointing to barriers to behavioural change. A mixed methodology study using questionnaires and focus groups was conducted in the Anglian and southern regions of the UK to explore public perceptions of drought and climate change. Respondents attributed the 2004–2006 regional drought to lower than average rainfall. Water-intensive lifestyles, a growth in population, increasing housing developments, leaking pipes and the privatization of water companies were also implicated. The majority of respondents claimed to change their behaviour to conserve water during 2006. Regarding the future, and under a number of different scenarios, people were more inclined to accept restrictions than agree to pay more to ensure the supply of water. They were concerned about climate change and recognized that more frequent water shortages may be one of the impacts, but this concern did not necessarily translate into action. Barriers to engagement with climate change and water-efficient behaviour included a lack of accessible information, a lack of knowledge regarding the integration of environmental spheres, a lack of resources, and a perceived lack of institutional engagement. The barriers identified appear to pose a major challenge to successful adaptation to climate change.  相似文献   
207.
为探究地下公共建筑能见度降低场景中,个体及小群体楼梯上行疏散特征,在某公共建筑楼梯间进行个体疏散和小群体疏散实验,分析不同能见度条件下个体在梯段及平台上的疏散速度、疏散行为、小群体特征等关键参数。研究结果表明:梯段速度受能见度影响程度大于平台速度,在正常能见度条件下,小群体行为会对疏散移动速度产生负面影响,在低能见度条件下,小群体行为有助于提升疏散效率,表现在小群体平均速度高于群体中最慢个体速度且小群体和个体之间的速度差异较小。  相似文献   
208.
Research on environmental activism remains poorly integrated and ill-defined and to date, there has been little examination of the relationship of environmental activism, pro-environmental behaviour and social identity. 131 students from an Australian University (M = 25.04 years old, SD = 8.17) voluntarily participated by returning an anonymous questionnaire containing an environmental activism scale, a pro-environmental behaviour scale and a social identity scale. The results revealed that while there was a significant relationship between social identity and environmental behaviour, only the citizenship component of environmental behaviour significantly predicted environmental activism. In other words, the relationship between social identity and environmental activism was indirect. This research presents the opportunity for further exploration of these relationships and to further investigate their relationship to inter-group processes.  相似文献   
209.
Since establishment of the ISO 14001 environmental management system in 1996, Japanese facilities have led the world in numbers of certifications. This research utilises survey data from more than 1700 Japanese facilities as well as follow-up interviews to identify the determinants of ISO certification, to examine the differences between early, recent and in-process certifiers, and to understand how ISO 14001 certification affects various environmental and managerial outcomes in Japan. Findings show that ISO certified facilities are larger and report higher levels of environmental management capacity. In addition, early certifiers are more likely to have established voluntary environmental agreements and are more active in international trade and business. Findings also provide evidence that while many facilities believe that ISO 14001 certification is excessively costly, they also report that certification has resulted in the establishment of new energy efficiency and waste reduction targets and higher target levels. Nevertheless, evidence indicates that certification does not generally result in longer-term outcomes such as post-certification adjustment of non-regulated targets.  相似文献   
210.
Engaging individuals in pro-environmental behaviours is critical to addressing today’s environmental challenges. This study examines how conditions – or an individual’s context – influence action. Through semi-structured narrative interviews and document analysis, we examined the influence of conditions in five individual cases involving attempted change in personal transportation behaviour. The cases, studied over the course of one year, are derived from participants in a sustainability institute, representing a range of attempted behaviours, and highlight numerous potential barriers to desired pro-environmental behaviours. We found that the degree of engagement with sustainable transportation primarily was influenced by the amount and intensity of supportive conditions relative to barriers. Participants who successfully engaged in their desired transportation-related pro-environmental behaviours experienced physical, social, and learning conditions that promoted competence and satisfaction. We discuss the implications for designing interventions that encourage pro-environmental behaviours.  相似文献   
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