The Communal Way of Life in the Splendid Wren,Malurus splendens

Splendid Wrens were studied over 7 breeding seasons in Western Australia. A colourbanded population (54 adults and 160 nestlings) of these small dimorphic passerines occupied a saturated habitat and dispersed little. Annual mortality of ♀♀ was 57% compared to ♂♂ at 29%; this high rate of turnover of ♀♀ reduces the chances of inbreeding. 2/3 of the territorial groups contained one or more helpers; groups with helpers did not produce more young than those without, but the helping role ensured priority of opportunity to inherit their own group-territory or to succeed to a neighbouring one, wheresoever breeding vacancies occurred. Helpers reduced the stress on breeding ♀♀ in many ways.     

Urine Marking and Territoriality in Galago alleni (Waterhouse, 1837 — Lorisoidea,Primates) — A Field Study by Radio-telemetry

Behavioral interactions among color-marked individual Vidua chalybeata that shared common song dialects were observed for 5 years in two populations at Lochinvar National Park, Zambia. Social interactions involved ♂♂ visiting and competing for mating sites and ♀♀ visiting ♂♂ in an apparent sampling of potential copulating partners. Differences in mating success among the polygynous ♂♂ were compared with male behavior and territory resources, and criteria were developed to test the importance of intrasexual male competition and female mate choice in explaining the mating system of the populations. Song behavior best explained differences in mating success of ♂♂ with lesser effects of neighboring ♂♂ and the defensible resources around the call-sites. The social organization of song populations resembles that of a dispersed lek with ♀♀ visiting many ♂♂ but mating with few ♂♂. We discuss the observations on indigobirds in relation to behavioral selection, sexual selection, and mating systems. Mating systems of certain populations and species are compared using statistics of individual mating success.     

Morphometric and DNA investigations into European water frogs (Rana kl. esculenta Synklepton (Anura, Ranidae)) from different population systems

The population specific variability of diploid and triploid R. kl. esculenta individuals was investigated by means of morphometric methods (canonical discriminant analysis, UPGMA cluster analysis) and DNA fingerprinting. As a result of the morphometric investigations, as well as of the DNA investigations, a clear separation of single populations was possible. However, no correlations between the morphometry and different population systems could be recognized. Clear morphometric differences could be seen between diploid ♀♀ and ♂♂ and triploid ♀♀ on the one hand, and triploid ♂♂ on the other. While the diploid ♀♀ and ♂♂ and the triploid ♀♀ were located in the intermediate area between the parental species R. lessonae and R. ridibunda according to their morphometric parameters, the triploid ♂♂ showed a great overlap with R. lessonae. Up to now, this phenomenon has not been explained. The first results of the DNA investigations provided further hints at the high inter-individual and population-specific variability of R. kl. esculenta. R. kl. esculenta individuals of the R. lessonae/esculenta population Toter See could be distinguished from conspecific individuals of the R. ridibunda/esculenta-♀♀ population Alte Oder according to their fingerprint patterns. Moreover, in the R. lessonae / esculenta population, the fingerprints or the diploid R. kl. esculenta-♀♀ and the investigated R. lessonae-♀ were very similar. Furthermore, in this population, many R. kl. esculenta genotypes resemble R. lessonae in their morphometric features. This finding suggests the occurrence of recombination in R. kl. esculenta. In general, every population seems to have its own genetic background. A classification of water-frog populations according to population systems is only possible under certain conditions.     

Density and Lek Displays in Drosophila grimshawi (Diptera: Drosophilidae)

Frequencies of stereotyped lek displays of male Drosophila grimshawi were measured in groups of different sizes (2, 4, 8, or 16 ♂♂ per container). In one experiment ♀♀ were absent, and in a second experiment two ♀♀ were present in each male group. In both experiments the frequency of courtship displays was linearly dependent upon density. Two agonistic displays and a communal display were density-dependent only when ♀♀ were present. The strategy ♂♂ adopted only in the presence of ♀♀ was: (1) to balance the relative frequencies of communal and aggressive behavior, and (2) to increase the ratio of contact to noncontact aggression with increasing density.     

Interspecific Communication in Fiddler Crabs: Preliminary Report of a Female Rejection Display Directed toward Courting Heterospecific ♂♂

A newly described display is apparently used by female fiddler crabs (genus Uca) in interspecific communication. The display, termed repetitive-high-rise, is directed primarily toward courting heterospecific ♂♂, which approach or are likely to approach the ♀. We postulate that the display serves to indicate the ♀'s unavailability to these ♂♂ for mating. The ♂♂ respond appropriately by ceasing their approach toward displaying ♀♀. Both reproductively receptive and unreceptive ♀♀ were observed to perform this display. ♀♀ appeared to be able to discriminate, not only between conspecific ♂♂ and heterospecific ♂♂, but also among ♂♂ of heterospecific species. The possible significance for this ability is discussed.     

Sexual Discrimination Using Visual Cues in the Checkered White Butterfly (Pieris protodice)

The cues used by ♂♂ and ♀♀ of the checkered white butterfly, Pieris protodice, were explored using an assay that involved timing the responses of free-flying butterflies to tethered animals (“angling”). The models included ones that were made from the wings of ♂♂ and ♀♀ that had been extracted in a dilute ammonia solution. This procedure removes an ultraviolet-absorbing pigment from the wings and renders them more ultraviolet reflectant than normal without altering any other aspect of their coloration. The results show that both sexes make sexual discriminations using the sexual dimorphism in ultraviolet reflectance found in this species rather than using differences in the melanic markings on the wings, movement patterns, or chemical signals.     

The Behaviour of the Mediterranean Tripterygion Species (Pisces,Blennioidei)

The behaviour of the three mediterranean benthic fish Tripterygion tripteronotus, T. xanthosoma, and T. melanurus is described from observations in the field and observations on captive animals. The ♂♂ defend a territory only during the reproductive season; ♀♀ do not defend a territory. At the height of the breeding season, a male T. tripteronotus on average spawns with four ♀♀ Per day. The ♂ defends the territory against egg predators and cleans the eggs. ♀♀ spawn repeatedly during a spawning season. A spawning pair of T. tripteronotus frequently attracts conspecifics. The majority of these “satellites” are small, sexually mature ♂♂, which do not own a territory themselves. The reproductive strategies of the two types of ♂♂ (territorial ♂♂ and satellite ♂♂) and of the ♀♀ are discussed. On the basis of ethological, morphological, and palaegeographic data the evolution of the eastern-atlantic and mediterranean Tripterygiidae is reconstructed. A bibliography of the literature on eastern-atlantic and mediterranean Tripterygiidae is given. As in their morphology and anatomy, benthic fish show convergent adaptations in their behaviour. Some of these are pointed out and discussed.     

Play Partner Preferences in Siberian Ibex,Capra ibex sibirica

A study of social play in Siberian ibex kids at the Chicago Zoological Park revealed clear play partner preferences. Male kids played much more among themselves than with female kids and elicited more withdrawals by play partners than did ♀♀. ♂♂ and ♀♀ in mixed-sex bouts, played mostly with similarly aged partners. Male kids played a substantial amount with female yearlings; female kids did not. These differences support a motor training explanation of social play because they suggest that young ♂♂ in this sexually selected species discriminate in favor of partners with whom they can play forcefully.     

Effects of Androgens and Oestrogens on the Behaviour of Chicks in an Imprinting Situation

The behavioural effects of testosterone propionate (TP), 5α-dihydrotestosterone (DHT) and oestradiol benzoate (OB) were investigated in day-old chicks during imprinting sessions to a duck model. TP increased the duration of peeping while inhibiting the following reaction and the twitters. DHT had more or less the same effects while OB induces the reverse behavioural changes. The behavioural effects of hormone injections agree with behavioural sex differences observed in non-injected animals: ♂♂ peep more than ♀♀ which on the other hand produce more twitters. This could be related to sex differences in the hormonal status of the birds at hatching, as it is known that during incubation male chick embryos have higher plasma testosterone levels than ♀♀ of corresponding ages.     

Sex-differences in the Agonistic Behavior of Spiny-mice (Acomys cahirinus)

Observations of 8 groups each containing three adult spiny mice (Acomys cahirinus) revealed that instances of chasing and physical displacement were quite common, while fighting and biting were rarely observed. The relationships between the most frequent behavioral categories were presented in a correlation matrix. In a second, study, ♀♀ tested in their home cages were dominant over ♂♂ In the ♂♂ home cages, however, no differences in the frequency of ♀ vs. ♂ aggression were observed. More instances of aggression were observed in the cages of the ♀♀ than in the cages of the ♂♂.     

Display Specificity and Reproductive Isolation in the Fiddler Crabs,Uca panacea and U. pugilator

The factors responsible for reproductive isolation between two sibling species of fiddler crabs (Uca pugilator and U. panacea) were studied under both laboratory and field conditions. ♂♂ showed species differences in their visual and acoustical displays. These differences were exaggerated in the overlap zone, where U. pugilator showed character displacement of its acoustic signals. ♀♀ of U. pugilator confined with ♂♂ of U. panacea produced fewer clutches of young. Occasionally, forced matings took place in the laboratory, resulting in hybrids suffering greater mortality through development. The data indicate that both premating (behavioral) as well as postmating (higher larval mortality) barriers act to prevent interbreeding.     

The Effects of Crowding on the Social Relationships and Behaviour of the Dwarf Mongoose (Helogale undulata rufula)

Since dwarf mongooses in captivity show an extremely stable familiar structure with no evidence of group break-up, the study was designed to place the animals under crowding stress to determine whether such tendencies would be manifested and whether compensatory mechanisms to maintain group cohesion are present. A stable family group of 12 animals was investigated and observations over 150 h under control and 120 h under crowded conditions made. The results show that social pressure is mainly exerted on subordinate adult ♂♂ and ♀♀, sometimes resulting in their death by stress-induced uraemia, through increased aggression by the a pair. The social system stabilises after 16 days but high intra-group aggression/submission remains. Synchronisation of oestrus cycles in nubile ♀♀ resulted in simultaneous littering with loss of all young. The significance of these findings for population regulation is discussed.     

Comparison of dispersal and other movements in two Badger (Meles meles) populations

The dispersal and other movement patterns in two Badger populations, one in rural Gloucestershire and the other in suburban Bristol, are described and categorized into nine different types of movement. Movements were less common in the high density Badger population in Gloucestershire, but disturbance increased the likelihood of movements occurring. In the lower density Bristol population, where the social structure was more fluid, movements were more common. However, in both populations truly itinerant Badgers appeared to be rare. More male than female Badgers moved, but for each type of movement there was no difference in the distance moved by males and females. Movements were rare in animals less than a year old; most movements occurred in sexually mature animals, i.e. those more than 2 years old.     

The Ethology and Sociology of the Dwarf Mongoose (Helogale undulata rufula)

Sexual imprinting is a well-known phenomenon in the ♂♂ of many bird species, but its occurrence in ♀♀, particularly of dimorphic species, has been questioned. ♀♀ of the Zebra Finch, Taeniopygia guttata, that had been cross-fostered by Bengalese Finches, Lonchura striata, were tested for their preferences in two different choice tests involving ♂♂ of both species. A highly significant preference for the imprinted species was found.     

Sexual Selection in the Three-Spined Stickleback

The purpose of this study was to seek evidence for the influence of sexual selection on both male and female three-spined sticklebacks, a species in which the ♂ alone has parental responsibilities. We studied the intrasexual relationships of ♂♂ and ♀♀ prior to courtship, and the intrasexual and intersexual relationships of both sexes during courtship. Results demonstrated that both ♂♂ and ♀♀ compete intrasexually, and suggested that both sexes are discriminative in mate selection. These results are compatible with Trivers' (1972) model of the role of parental investment in sexual selection.     

The Importance of Human Odour in Non-verbal Communication

Calling assemblies of Hypsignathus monstrosus were studied for 17 months in the field to determine if they were “leks” or mating arenas. Direct observations, netting of animals at the assembly sites, and radio-tracking of both ♂♂ and ♀♀ at the assembly sites, foraging grounds, and day roosts were all utilized to make this determination. Captive animals were maintained to establish growth rates. It is concluded that Hypsignathus exhibit lek behavior even by the most conservative definition and share many features with other avian and mammalian lek species.     

Regulation of damseifly populations: the effects of larval density on larval urvival, development rate and size in the field

SUMMARY. 1. The popuhttion density of Coenagrion pttella larvae was monitored in five populations, and of Ischntira elegans in two populations, between October 1982 and May 1983.
2. There was no measurable mortality of larvae over winter and no larval growth until April. Larvae in high density populations were smaller than those in low density populations and were more likely to have a semi- voltine life history.
3. The population density of C. ptiella was also monitored (more frequently) in two populations with differenl initial densities between July and November 1983. In the high density population there was a constant rate of larval mortality, while in the low density population there was no detectable larval mortality, indicating that larval mortality may be density dependent. Larvae in the high density population were again smaller, and more likely to be semi-voitine, than those in the low density population.
4. The role of density dependent larval growth, development and mortality in the regulation of damseifly populations is discussed.     

Effects of an exceptionally snowy winter on chamois survival

Although weather-induced mass mortalities of wild ungulates have been reported, no study has quantified how these episodes may affect the survival of prime-aged adults. Long-term studies of marked ungulates have instead consistently found very weak or no effects of weather on the survival of this age class, particularly for females. We report on the effects of the exceptionally snowy winter of 2008–2009 on three populations of chamois in the western Alps: two in Italy, one in France. In the Alpi Marittime Natural Park in Italy, mortality of prime-aged females (aged 2–9 years) was 43%, about five times higher than reported by previous studies of chamois. Just across the continental divide in the adjacent Mercantour National Park (PNM) in France, however, prime-aged female mortality was only 6%. Senescent females suffered very high mortality in both populations (100% and 56%). In the Gran Paradiso National Park in Italy and in the Alpi Marittime Natural Park, adult male mortality rate was respectively of 81% and 44%, whereas in the PNM, it was only 10%. A recent reduction in population density in the French population, or lower absolute snowfall than in Italy, may explain the difference in survival. Survival of males and prime-aged females can be affected by exceptional weather events, possibly in combination with high population density. Adult chamois of both sexes appeared to show elevated mortality in response to harsh winter conditions. Our results underline the importance of considering sex and age classes in evaluating the impacts of population density in wild ungulates.     

The Red Fox,Vulpes vulpes,as a Predator upon Earthworms,Lumbricus terrestris

The tiny (3.1–3.8 g) vespcrtilionid bat Pipistrellus nanus was studied in Kenya palm-thatched roofs from May 1973 to July 1974. Roosting social organization and related activities and behavior are described. ♂♂ held diurnal roosting territories where ♀♀ gathered in small and compositionally labile groups, attracted to the most vocal ♂♂. Annual variation in population-wide aspects of social organization follows predictable seasonal changes in climate and predator abundance. Variability between individuals follows a common mammalian pattern: high male competition for ♀, variance in presumed male reproductive success, and a mating system resembling one based on resource defense polygyny. Social organization in this population contrasts with that known from studies of other P. nanus populations.