摘要:

Abstract and SummaryPrevious studies that have looked at the aversive properties of simple, predator‐related, eye‐like patterns presented in an artificial context, have yielded conflicting results. The aim of the present series of experiments was to investigate whether such stimuli had potential for use as bird scarers. The starling (Sturnus vulgaris) was the subject species. The experimental procedure was designed to provide a relevant and objective, interval scale of aversiveness based upon the ability of eye patterns to deter hungry birds from a feeding area.Each subject was deprived of food for 5 h and then tested in an apparatus which exposed an eye pattern over a food trough immediately after the bird alighted on that trough. 10 measures of the starlings' feeding behaviour were monitored over a 1‐h trial. It was predicted that five of these variables would be positively and five negatively correlated with an increase in the fear evoking properties of the stimulus. The 10 measures were analysed using principal component analysis and the first component in every experiment had the signs of the latent vectors of the variables exactly in the predicted pattern and therefore appeared to be an ‘aversiveness index’. The scores from this first component were then used in a Latin square ANOVA to distinguish subject, test order and stimulus effects.The main findings from the eight experiments are as follows. Simple eye‐like patterns can indeed deter hungry starlings from feeding in their vicinity. The presence of a pair of eyes painted on a white card caused an 88% reduction in time spent on the nearby food trough and a 65% reduction in actual feeding time. The presence of ‘pupils’ in the patterns is essential for simple circles alone are not significantly more aversive than the control card. Once a pattern has the ‘pupil/iris’ distinction then a circular outline becomes important although the shape of the ‘pupil’ appears relatively unimportant. Eyes with coloured irises are more effective than black and white patterns but the degree of contrast between the ‘pupil’ and ‘iris’ appears irrelevant. Increasing the number of simultaneously presented eyes from one to three is correlated with an increasing trend in aversiveness which is destroyed if the same stimuli are presented within the context of a simple head outline. Changing the orientation of a pair of eyes from horizontal to vertical only slightly reduces their aversiveness. The size of the patterns appears to be unimportant within the range tested. The aversive properties of eyespots and of broadcast starling distress calls are positively additive. The effectiveness of a stimulus combining all the important features mentioned is as aversive as is a realis

ISSN:0044-3573    

DOI:10.1111/j.1439-0310.1983.tb02151.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Abstract and SummaryThe behaviour of the spider crabInachus phalangium(Fabricius, 1775), which lives in association with the sea anemoneAnemonia sulcata(Pennant), was studied in the field.The crab was found in the littoral zone of the Mediterranean Sea near Banyuls sur Mer, France, in the whole depth range studied (0.5–25 m). The crabs had a long‐lasting association with individualAnemonia sulcata, occasionally withAiptasia mutabilis.Most crabs were found in association with the same anemone for several days, some crabs were found in association with the same anemone for longer than one month.In the areas studied, on average 65Inachus phalangiumwere found on 100 anemones.Crabs released in the vicinity of anemones moved towards them and entered them.Inachus phalangiumcould walk between the tentacles ofAnemonia sulcataandAiptasia mutabiliswithout eliciting feeding reactions of the anemone. The crabs left the anemones for moulting. After moulting masking material was removed from the exuvia and used again. The animals returned into an anemone while still soft. Material used for masking, usually algae, could be picked off the body and eaten. Masking material may be a food reservoir in addition to providing camouflage.Anemones were left only during night‐time. The crabs left their anemone to moult, to feed in the vicinity, fleeing from larger conspecifics, and to migrate to a different anemone.Outside the anemone's protectionInachuswas eaten by several species of fish.Individuals appeared to avoid each other. 57% of all animals were found alone on an anemone. Large males and females were more frequently found alone than were small males and females. Fights were observed between members of the same and of the opposite sex. During fights, legs and claws could be torn off.Adult males migrated more often between anemones and moved over larger distances when migrating than did adult females. Adult males probably migrated in search of sexually mature females. Such a roving strategy is evolutionarily stable only when the higher costs (in terms of energy expenditure and mortality) are compensated for by a higher number of offspring than produced in the alternative, pair‐bonding s

ISSN:0044-3573    

DOI:10.1111/j.1439-0310.1983.tb02152.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Abstract and SummaryInvalid care has already been recorded for a group of captive dwarf mongooses and incorporated huddling round the sick animal, grooming it and giving it preferential access to food. The behavioural responses of a wild group towards an injured group member were essentially the same as described above. In addition, the group members restricted their foraging both spatially and temporally until the injured animal could accompany them normally. Invalid care in this species may be related to the importance of the presence of a large number of adults in the group, groups with few adults having less success in raising their young than larger groups and being especially vulnerable to terrestrial predator attack.

ISSN:0044-3573    

DOI:10.1111/j.1439-0310.1983.tb02153.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Abstract and SummaryThe ecology and behavior ofTayassu tajacuandT. pecariwere studied for a total period of 16 months in the years 1975–1978 in the Manú National Park in southeastern Perú.It appears from 132 sightings ofT. tajacuat the study site, and from reports from other regions, that groups of this species in rain forest usually contain fewer than 12 individuals. The more observers were at the study site, the more frequently this species was encountered.T. tajacualso repeatedly used wallows in the forest. These observations suggested that individuals of this species were relatively sedentary.Herds ofT. pecariwere encountered on 60 occasions. Five counts indicated that there were over 100 individuals in the herds. This species was encountered at practically random intervals, independent of number of observers at the site, but more frequently in the dry season than in the rainy season.Adults of both species are prey primarily of large cats and humans.Both species feed on green plant parts, fruits, nuts and seeds, butT. pecarifeeds on more resistant seeds and nuts thanT. tajacu.The hardest palm nuts that onlyT. pecarican consume are distributed in a patchy manner. Cracking these nuts between the teeth causes the animals to be heard more than 50 m away.The patchy distribution of the hard nuts and seeds preventsT. pecarifrom being sedentary, and group formation likely has several individual benefits for foraging efficiency and defense against predators. These may include (1) avoidance of searching for food in places recently visited by others, (2) benefitting from the knowledge of experienced foragers, (3) reducing the per capita probability of detection by predators, (4) reducing the probability of being captured after group detection by predators, (5) increasing the ability to counterattack as a group, (6) increasing the probability of detecting the predator before it can attack, and (7) “confusing” the predator through escape behavior.T. tajacuseems to live in small groups because its typical foods are distributed more evenly and because consumption of these foods does not cause individuals to be so noticeable to pr

ISSN:0044-3573    

DOI:10.1111/j.1439-0310.1983.tb02154.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Abstract and SummaryThe response to playback of three different dialects by 10 territorial male corn buntings was investigated; the dialects played were own dialect, the dialect of a neighbouring population (NEAR) and a dialect from 40 km away (FAR). A significant effect of dialects was found for two measures of response, latency and singing rate. Response strength varies in the pattern OWN>NEAR>FAR for these measures. This pattern of response would not maintain the observed homogeneity of dialect populations. The results are similar to those obtained by experiments on other dialect species.

ISSN:0044-3573    

DOI:10.1111/j.1439-0310.1983.tb02155.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Book reviewed in this article:Bücher/Books: Harrington, F. H., and P. C. Paquet, eds. (1982): Wolves of the world. Perspectives of behaviour, ecology, and conservation (Die Wölfe der Welt. Verhalten, Ökologie und Schutzmaßnahmen).Bücher/Books: Dover, G. A., and R. B. Flavell, eds. (1982): Genome evolution (Genom‐Evolution).Bücher/Books: Dawkins, R. (1982): The extended phenotype. The gene as the unit of selection (Der erweiterte Phänotyp. Das Gen als die Einheit der Selektion).Bücher/Books: Maynard Smith, J. (1982): Evolution and the theory of games (Evolution und Spieltheorie).Bücher/Books: Kemp, T. S. (1982): Mammal‐like reptiles and the origin of mammals (Säugerähnliche Reptilien und die Entstehung der Säugetiere).Bücher/Books: Senglaub, K. (1982): Sie sind veränderlich. Eine Einführung in die Fortpflanzungs‐ und Evolutionsbiologie der Tiere (They are variable. An introduction to reproductive and evolutionary biology).Bücher/Books: Barth, F. G. (1982): Biologie einer Begegnung. Die Partnerschaft der Insekten und Blumen

ISSN:0044-3573    

DOI:10.1111/j.1439-0310.1983.tb02156.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY