bluuebunny/crossref_metadata_2025_split huggingface dataset:
Individual Odors in Djungarian Hamsters (Phodopus campbelli)
Authors: Lai Syau‐Cheng , Johnston Robert E. 
Published: May 2010

AbstractThe sources of scent in Djungarian hamsters (Phodopus campbelli) that may be individually discriminated were investigated using an habituation paradigm. Male Djungarian hamsters were exposed to five presentations of a particular scent from one individual, and then to the same scent from a novel individual. Increased investigation of the scent from the novel individual indicated discrimination of scents from different individuals. Male hamsters distinguished individual differences in scents of other males from the midventral gland, urine, feces, mouth, and the corner of the mouth, which includes the sacculi; they did not discriminate among odors of different individuals when the scents were from the genital region, hindfeet, fur from behind ears or fur from the back. The results indicate that Djungarian hamsters have a repertoire of individually distinctive scents that are located in specific places on the body; these scents are not actively distributed to, nor passively picked up on, other parts of the body. The fact that scents from some areas do not contain individually distinctive information suggests that some sources may be specialized for producing individually distinctive scents.
Mate Sampling and Assessment Procedures in Female Pied Flycatchers (Ficedula hypoleuca)
Authors: Hovi Matti , Rätti Osmo 
Published: May 2010

AbstractModels of mate sampling strategies predict that choosiness should decrease throughout the breeding season due to increasing costs of delaying mating. Therefore, individuals who start searching mates relatively late, should spend less time on sampling, and sample fewer candidates compared to early individuals. We observed mate searching behavior of female pied flycatchers (Ficedula hypoleuca) by radio‐tracking in study areas with 6–12 unpaired males. Contrary to the prediction, the observed numbers of males sampled by the searching females increased with time, i.e. late arriving females visited more males than early arrivers. However, this seems to be due to more active sampling of males in short time by late‐arriving females. The observed sampling pattern suggests some kind of comparison tactic, which seems, however, to be very variable among individual females. Mate‐assessing females were characterized by a remarkably cryptic behavior, which may be 1) a way of gaining honest information about the male mating status or male/territory quality, or 2) a way of avoiding courtship costs.
The Influence of Substrate Color on the Alarm Response of Tidepool Sculpins (Oligocottus maculosus; Pisces, Cottidae)
Authors: Houtman Robert , Dill Lawrence M. 
Published: May 2010

AbstractFor animals that use crypsis to avoid predators, immobility reduces the risk of detection. The magnitude of this immobility benefit depends upon the probability that a predator is present, since a predator must be present for crypsis to be valuable. Thus, cryptic animals typically reduce their movement rates upon detection of a nearby predator or signs of its activity. Such a response occurs in tidepool sculpins (Oligocottus maculosus) when presented with water‐borne compounds released from the skin of injured conspecifics (Hugie et al. 1991). The benefit of immobility should also depend upon the animal's background, or substrate, since animals on a matching substrate achieve a higher level of crypticity than those on a nonmatching substrate, and have more to gain by remaining still. Therefore, we predicted that the response of tidepool sculpins to conspecific skin extract would involve a greater reduction in movement rates for fish on sand (matching) than for those on white (nonmatching) substrate. The results of a laboratory experiment supported this prediction, with fish on sand showing a large decrease in movement rates in response to skin extract, while the movement rates of those on white substrate remained unchanged.
The Dilution Effect and Differential Predation Following Brood Adoption in Free‐ranging Convict Cichlids (Cichlasoma nigrofasciatum)
Authors: Wisenden Brian D. , Keenleyside Miles H. A. 
Published: May 2010

AbstractParental investment in unrelated offspring is potentially maladaptive but may be promoted by natural selection if the presence of foreign young enhances the survival of the parents' own young. We experimentally augmented broods of free‐ranging convict cichlids (Cichlasoma nigrofasciatum) to test whether survival of the adopting parents' young (fry) increases, in relation to that of control broods, after the addition of smaller foreign fry, and whether such an increase can be attributed to the effect of brood dilution acting alone or to a combination of brood dilution and the effect of differential predation on adopted young. Total fry survival did not differ between experimental (E) broods and control (C) broods, but E broods had significantly more large (host) fry after 5 days and 10 days than C broods did. In E broods, small (foreign) fry suffered higher rates of predation than large fry, indicating differential predation. In E broods starting at 7.0 and 7.5 mm standard length (SL), observed fry mortalities did not differ significantly from mortalities expected from the effect of brood dilution. However, E broods starting at 8.0 mm SL had significantly lower mortalities than expected, indicating that parents that adopt smaller foreign fry can increase the survival of their own fry by the combined effects of brood dilution and differential predation. Within E broods, growth of smaller foreign fry was significantly slower than that of larger host fry, suggesting that intra‐brood agonistic behaviour affects access to food for smaller fry. Therefore, increased predation and reduced growth are two negative effects that act on fry of donor parents.
Alternative Male Spawning Tactics and Acoustic Signals in the Plainfin Midshipman Fish Porichthys notatus Girard (Teleostei, Batrachoididae)
Authors: Brantley Richard K. , Bass Andrew H. 
Published: May 2010

AbstractThe plainfin midshipman Porichthys notatus has two male reproductive morphs, ‘Type I’ and ‘Type II’, which are distinguishable by their physical traits alone. Type I males are eight times larger in body mass than Type II males and have a six‐fold larger relative sonic (vocal) muscle mass than Type II males. In contrast, the testicles of Type II males are seven times larger than those of Type I males. This study demonstrates morph‐specific patterns of reproduction, including acoustic signals, for Type I and II males. Field censuses of nests showed that only Type 1 males maintained nests. Type II males and females transiently appeared in these nests in association with each other. Infra‐red video and hydrophone recordings in aquaria showed that Type I males maintained nests and readily vocalized. Long‐duration ‘hums’ and sequences of short‐duration ‘grunts’ were produced during advertisement and agonistic contexts, respectively. Humming Type I males attracted females to their nests, pair‐spawned, and then guarded egg clutches alone. By contrast, Type II males neither acoustically courted females nor maintained available nest sites, but rather ‘sneak‐’ or ‘satellite‐spawned’ at the nests of Type I males. Type II males infrequently produced low amplitude, short duration grunts that were similar in spectral, temporal and amplitude characteristics to the grunts of females. Type II males appear to be obligate sexual parasites of the nest‐building, mate‐calling, and egg‐guarding Type I males. The dimorphic body and vocal muscle traits of the two male morphs in the plainfin midshipman are thus paralleled by a divergence in their reproductive tactics and the properties of their acoustic signals.
Age, Experience, and the Response of Streamside Salamander Hatchlings to Chemical Cues from Predatory Sunfish
Authors: Sih Andrew , Kats Lee B. 
Published: May 2010

AbstractPrevious work has shown that streamside salamander larvae (Ambystoma barbouri; Ambystomatidae) exhibit an adaptive ‘sink to the bottom’ response to chemical cues from predatory green sunfish (Lepomis cyanellus; Centrarchidae), that is, larvae sink to the bottom more quickly (thus minimizing exposure time to sunfish predation) when they are dropped into water with sunfish chemicals (as compared to Ashless controls). Here, we examined this anti‐predator behaviour in early hatchlings and the effects of age and experience on subsequent expression of this behaviour. Hatchlings responded significantly to fish chemical cues within the first 18 h after hatching. Age did not significantly influence this response, i.e. regardless of age (1, 7, or 14 days after hatching) larvae showed a significant response during their first exposure to fish chemical cues. Experience also did not significantly influence the larval response to fish chemicals i.e., repeated exposures over 2 weeks did not significantly influence the magnitude of the response. Finally, comparisons of 3 siblingships detected significant variation among siblingships that might reflect genetic variation in this behaviour.
Nocturnal Mate Recognition and Nest guarding by Female Convict Cichlids (Pisces, Cichlidae: Cichlasoma mgrofasciatum)
Authors: Reebs Stephan G. 
Published: May 2010

AbstractThis study investigated the ability of nest‐guarding convict cichlid (Cichlasoma mgrofasciatum) females to recognize their own mate and to defend their brood effectively against strangers at night. Cichlids in the laboratory bred in nesting boxes made of plexiglas. At the fry stage, various conspecific males were introduced, at night, into the nest box of brood‐guarding females. Female reaction was observed with infrared equipment. If the introduced male was their own mate, females showed little reaction. If the introduced male was a stranger, females reacted by directing head shakes, tail beats, and pushes or bites at the intruder. The frequency of these acts was significantly higher in the presence of strangers than in the presence of mates; the frequency also rose significantly as the size of strangers increased. The two largest classes of strangers fought with the females. These fights included circling behaviour, but not mouth‐locking. Some aspects of female behaviour suggested that mate recognition is based on short‐range chemical cues and not on sound, size, or rapidly diffusing odours. Mate recognition in the nest, at night, is an example of non‐visual communication in fish, and active nest defense at night shows that the convict cichlid, normally considered to be diurnal, can engage in coordinated and effective behaviour in the absence of light.
Imprinting Effects on Host‐Selection Behaviour of Colony‐FoundingChalepoxenus muellerianus(Finzi) Females (Hymenoptera, Formicidae)
Authors: Schumann Ralf D. , Buschinger Alfred 
Published: May 2010

AbstractHost selection behaviour during colony foundation of newly inseminatedChalepoxenus muellerianusfemales belonging to three different imprinting types was investigated. Imprinting occurs both in larvae and in the young adults. It strongly influences the slavemakers' host choice. Young females get imprinted onto that slave species which is already present in the slavemaker colony. If nests of several potential host species are present in the habitat, the females will prefer the ‘familiar’ species for colony foundation. In addition to the imprinting influences, an innate preference ofC. muellerianusfor its main host speciesLeptothorax unifasciatuswas demonstrated. Host selection behaviour ofC. muellerianusfemales therefore depends on a blend of innate and learned characters. A genetically mediated preference of a certain host species can be reinforced by imprinting‐like phenomena. On the other hand, the same processes probably facilitate a change of the host species, for example in habitats, where the main host species is rare, and females are forced to switch over to other potential host species for colony foundation.
Parasites and Female Ability to Defend Offspring in the Parent Bug Elasmucha grisea L
Authors: Mappes Johanna 
Published: May 2010

AbstractThe specialist endoparasite Subclytia rotundivertis Fallen (Diptera; Tachiniidae) uses the subsocial parent bug Elasmucha grisea L. (Heteroptera; Acanthosomatidae). The parasite injects a single egg through the upper prothorax of female bugs and after hatching the larval parasites eat their host. Parasitism affected only slightly a female's ability to defend her brood when the nymphs were at the second instar stage. However, with third‐instar nymphs, parasitized females responded markedly less to disturbance at all levels of their defensive behaviour. Parasitism reduced female survival and significantly increased the probability of death before the end of maternal care. Thus, the main cost of parasitism to Elasmucha females seems to be a reduced period of maternal care of the nymphs.
Alternative Mate‐locating Tactics in Chlosyne californica (Lepidoptera, Nymphalidae)
Authors: Alcock John 
Published: May 2010

AbstractTwo different mate‐locating tactics coexist within the California patch butterfly (Chlosyne californica): territorial defence of perch sites on hilltops and non‐territorial patrolling of slopes and washes. Patrolling males were observed only during periods of high population density. At these times, some marked individuals used both tactics, indicating that they possessed the behavioural flexibility to practice either hilltop territoriality or downslope patrolling. Downslope patrolling was not simply a ‘making‐the‐best‐of‐a‐bad‐job’ option for males unable to secure territories. First, patrollers were not smaller on average than territorial males. Second, downslope patrollers typically became most numerous several hours after the hilltopping territorial males peaked in density. In the late morning and midday when patrollers predominated, temperatures were relatively high (perhaps facilitating patrolling flight) and foraging females (some of which were sexually receptive) were much more abundant. Patrolling is therefore likely to be a mate‐locating supplement to hilltopping rather than an inferior substitute for it.
Role of Helpers in the Sentinel Behaviour of the Florida Scrub Jay (Aphelocoma c. coerulescens)
Authors: Hailman Jack P. , McGowan Kevin J. , Woolfenden Glen E. 
Published: May 2010

AbstractTwo independently conceived and executed field studies using somewhat different methodologies tested the hypothesis that non‐breeding helpers of the Florida scrub jay (Aphelocoma c. coerulescens) contribute importantly to antipredator sentinel behaviour. Specifically, we made four predictions: 1. Helpers participate to a non‐trivial degree in sentinel behaviour; 2. Breeding pairs with helpers spend less time on sentinel behaviour and hence more time foraging; 3. Breeders with helpers have more protected foraging time; and 4. Groups with helpers have greater total sentinel time.Results of the two studies agreed on most major points and even, in many cases, on minor points and quantitative aspects. Non‐breeding adult helper birds participated in sentinel watches almost as much as breeders in their group. In winter, breeding pairs with one or more helpers decreased their own sentinel time compared with that of unassisted pairs. However, in the one study, the concomitantly increased available foraging time of breeders was no better protected by another group member being on sentinel than in the lone pairs. Results of the other study showed a significant increase of protected foraging time for breeding males only. In winter, groups with helpers did not have increased total sentinel time; time was either the same (Study A) or significantly less (Study B). During nesting, breeders with helpers did not decrease their sentinel effort relative to lone pairs. Instead, groups with helpers had a sentinel for more time. These results are interpreted as indicating that, in winter, sentinel behaviour is more important to antiraptor defense in lone pairs than larger groups. In groups with helpers the mere addition of extra pairs of eyes and ears may render formal sentinel behaviour less necessary, so breeders can decrease their sentinel time and increase their foraging time. During nesting, additional sentinels may be important for increased nest protection. The presence of helpers contributing to predator detection may thus be an important factor in the better annual survival and nesting success of breeders that have helpers (Woolfenden & Fitzpatrick 1984).
Kin‐biased Behaviour in Male Wild House Mice: Mixed‐paternity Grouping and Group Member versus Kin Discrimination
Authors: Smith Jeremy , Barnard C. J. , Hurst Jane L. 
Published: May 2010

AbstractKin bias during social interaction among house mice (Mus musculus) is influenced by learned odour cues used by the animal when encountering and interacting with other individuals. In this experiment with wild mice, the source of these odour cues was investigated by cross‐fostering single male pups between unrelated litters to create mixed‐paternity litters. Observation of dyadic interactions involving juvenile or adult mice reared in mixed‐paternity litters and unfamiliar animals reared in single‐paternity litters showed a bias in social investigatory and passive contact behaviours towards (a) an individual's own kin or the kin of an unrelated foster‐littermate and (b) the unrelated foster‐littermate of a relative, compared with (c) an unfamiliar unrelated control. The functional significance of kin bias is discussed in the light of the role of odour cues in recognizing familiar social group members and the transfer of odours between individuals within groups.
Copulation‐solicitation Displays in Female Canaries (Serinus canaria): are Oestradiol Implants Necessary?
Authors: Leboucher Gerard , Kreutzer Michel , Dittami John 
Published: May 2010

AbstractThe aim of this study was twofold: 1. To study the timing of copulation‐solicitation displays (CSD) in female canaries during a natural breeding cycle; 2. To address the question of the adequacy of invasive methods such as oestradiol treatment. Towards these ends, we compared seven oestradiol‐implanted and eight control females. Moreover, temporal relationships between reproductive behaviour and plasma concentrations of luteinizing hormone and oestradiol were investigated.The results showed that: 1. CSD appeared about 3 d before egg laying, after the peak of nest building. The maximum number of CSD was observed at the beginning of egg laying. CSD disappeared when the last egg was laid, at the very beginning of incubation; 2. No significant difference was found between the two groups for any behavioural criterion, particularly CSD. No significant difference appeared between control and oestradiol‐treated females for luteinizing hormone concentrations. In contrast, oestradiol‐implanted females presented higher levels of oestradiol during nest building and during egg laying, 9–13 d after implantation (median 2.53 and 1.47 ng/ml for implanted females vs 0.57 ng/ml and undetectable levels for controls). Implantation had no effect on the progress of nest building, CSD exhibition, egg laying and incubation. Our results suggest that implantation with oestradiol is not necessary in female canary to obtain CSD since they breed readily in captivity and already have enough oestradiol. The similar results in both groups lead one to question the necessity of oestradiol priming in some female choice experiments.
Prey‐handling Behaviour of Newly Hatched Snakes in Two Species of the Genus Elaphe with Comparison to Adult Behaviour
Authors: Mori Akira 
Published: May 2010

AbstractThe prey‐handling behaviour of two species of Asian ratsnakes was studied in the laboratory. In experiment 1, effects of prey size and type (mouse, lizard and frog) on capture position, direction of ingestion, condition of prey at ingestion, and prey‐handling method were investigated using newly hatched Elaphe quadrivirgata. Prey size did not affect these variables except prey‐handling method in frog trials: large frogs were more frequently constricted after a delay of more than 1 s than small frogs, and small frogs were usually simply seized. On the other hand, prey type affected prey‐handling method: mice and lizards were more frequently constricted or pinioned than frogs. When hatchlings of E. quadrivirgata tried to coil around a prey animal immediately after striking, they frequently failed or released their coils within 10 s after striking. In experiment 2, prey‐handling behaviour of adult E. climacophora was examined with mice of various sizes. Adult E. climacophora tended to constrict large mice immediately after striking, whereas they simply seized small mice. Only one out of 38 mice which were constricted immediately after striking was released from the coils within the subsequent 10 s. Large mice were killed prior to ingestion, whereas small mice were swallowed alive. Large mice tended to be swallowed head first. Experiment 3 was conducted to investigate effects of mouse size on prey‐handling behaviour of newly hatched E. climacophora. Mouse size affected condition of prey at ingestion and prey‐handling method but not capture position and direction of ingestion. Possible relationships between feeding ecology and the differences of prey‐handling behaviour among Elaphe are discussed.
Adoption Behaviour in Little and Common Terns (Aves; Sternidae): Chick Benefits and Parents' Fitness Costs
Authors: Saino Nicola , Fasola Mauro , Crocicchia Elena 
Published: May 2010

AbstractAdoption seeking by semi‐precocial chicks of some bird species can be adaptive since it provides an alternative tactic to permit poorly cared‐for young to survive despite their neglectful parents' behaviour. Moreover, own‐nest desertion may enhance inclusive fitness of fugitive chicks by increasing survival prospects of siblings. On the other hand, adoption by breeding adults can be detrimental to foster parents' fitness if they invest resources in promoting survival of others' offspring at the expense of their own. In this study we report on the proximate causes and survival consequences of adoption seeking by chicks, and on the presumed costs of adoption sustained by foster parents in two colonial, ground‐nesting tern species: the little tern (Sterna albifrons) and the common tern (Sterna hirundo). Adoptions were frequent in little tern and, notably, in common tern colonies. Chicks that deserted their original brood were poorly fed compared with resident chicks, but crowding in the brood and age rank relative to nest companions did not influence the chances of desertion. Deserting their original brood was risky for little tern chicks since stray chicks experienced higher mortality than resident ones. Common tern chicks deserted their original nest significantly more often than little tern chicks. Adoptees of both species benefited by the same survival prospects as resident chicks. A negative correlation existed between the proportion of food given to strange chicks and seasonal fitness or chick survival rate of breeding pairs. This was not predictable because: (1) foster parents could have increased their parental efforts, thus ensuring the same survival prospects to their own chicks, and (2) chicks of foster parents could have been, in turn, adopted thus obliterating the negative fitness effects of adoption. The sexes were identical with respect to their proneness to provide food to strange chicks. We suggest that adoption seeking by little and common tern chicks has evolved as an alternative tactic that is pursued to counter the effects of poor parental care. Adoption behaviour seems maladaptive since it is accompanied by a reduction in seasonal fitness in both species. Possible alternative explanations for nest desertion and adoption behaviour are also discussed.