Marking pike fry otoliths with alizarin complexone and strontium: an evaluation of methods

Laboratory experiments demonstrated that both alizarin complexone and strontium are useful in mass marking of pike Esox lucius fry otoliths. Visual detection of alizarin complexone marks was considered more reliable than the quantitative analysis of strontium for differentiating marked and unmarked individuals after release in a Danish lake.     

Rates of predation on mammals by gombe chimpanzees, 1972–1975

Rates of chimpanzee predation on mammals are calculated using data on 75 kills recorded during focal observation in Gombe National Park, Tanzania, from January 1972 to April 1975. The chimpanzees were members of two study communities (Kanyawara, or Northern, and Kahama, or Southern, community), and were observed as focal individuals for 14,583 hr by more than 30 researchers and field assistants working in pairs. The rate of predation by females was too low to allow reasonable estimates. For males, the mean rate of killing during the study period was 0.31 kills per male per 100 hr (N=17 males), or 4.65 kills per 100 hr in the two communities. In contrast to results from Mahale Mountains, there was no difference in predation rate between wet and dry seasons. However, predation rates varied over time, increasing by four times between the first three and last four seasons of the sample period. In an average year the 15 adult and subadult male chimpanzees are calculated to have killed 204 prey per year in an area of 16 km², varying between 99 and 420 prey per year in periods of low and high predation rate. Red colobus were the most frequent prey, followed by bushpig and bushbuck. Predation rates varied greatly on different prey species, and were not related to either the proportion of time spent within 200 m of male chimpanzees, or to their population densities. In relation to encounter rates and population density, baboons, blue monkeys, and redtail monkeys were killed at a fraction of the rate of red colobus monkeys, which suffered severe mortality from chimpanzee predation. Predation on bushpig and bushbuck also appears to have been high in relation to population density. The amount of food provided by predation is estimated to have averaged 600 kg per year for chimpanzees in the two communities (totalling 14–17 adult or subadult males, 18–20 adult of subadult females, and about 19 infants or juveniles). This suggests that adult males consumed around 25 kg of meat per year, although any average figure undoubtedly masks considerable individual variation. Present data suggest that chimpanzees in Gombe and Tai National Park, Ivory Coast, prey on mammals at rates higher than other populations.     

Scent Marking in Female Prairie Voles: a Test of Alternative Hypotheses

We conducted three experiments with females in different stages of reproductive condition to test alternative hypotheses for the function of scent marking in female prairie voles, Microtus ochrogaster . The three reproductive categories were isolated females prior to sexual stimulation (anoestrous), sexually stimulated (oestrous) and lactating. Females in different reproductive condition were given the opportunity to scent mark clean unmarked substrate or areas that had previously been marked by adult females or adult males. The numbers of scent marks deposited by females did not differ statistically for females in different reproductive condition. However, there was a trend for anoestrous females to mark the most, oestrous females less, and lactating females the least. The lack of scent marking by lactating females might be to reduce conspicuousness to conspecifics or predators. Oestrous females tended to mark the most in the area marked previously by males, although the difference was not statistically significant.
Our results provide some support for a mate-attraction hypothesis and a territorial-defense hypothesis, but were most consistent with a self-advertisement hypothesis. Over marking was uncommon and did not differ by experiment or sex of previous donor. Our results suggest that the number and placement of scent marks by females are highly variable and function primarily to convey individual identity.     

A Common Marking Technique Affects Tadpole Behavior and Risk of Predation

In many studies, it is necessary for researchers to mark individual animals for later identification. It is often assumed in the interpretation of these studies that marks have no effects on the biology of the animals. This assumption is insufficiently tested, and, when it is, coarse assessments of negative effects are often used, such as survival and growth under simplified laboratory conditions. We examined the consequences of a common larval amphibian marking technique (staining with methylene blue) for wood frog tadpole behavior and survival in an ecologically realistic scenario (predation). We measured a number of tadpole behavioral variables, under baseline conditions and in the presence of olfactory cues of a predator, for marked and unmarked tadpoles. We then exposed pairs of tadpoles (one marked and one unmarked) to one of two predators and tested for the effects of marking on the susceptibility of tadpoles to predation. We found that marking suppressed the increase in movement rate that typically occurred in (unmarked) tadpoles in the presence of predator cues. Marked tadpoles were significantly more likely to be captured by predators, an effect that could not be attributed to this difference in movement rate. These results raise concern about the use of this staining method and highlight the need for studies involving marked animals to thoroughly address any relevant effects the marks may have on the biology of the subjects.     

Scent marking in a territorial African antelope: II. The economics of marking with faeces

Faeces may be ideal substances for scent marking because they have a minimal energetic cost to the signaller. However, marking with faeces is also constrained by the animal's ability to produce faeces. This study examined whether limits on the volume of faeces produced by oribi Ourebia ourebi, in Serengeti National Park, Tanzania, caused territorial males to regulate their output and prioritize the placement of faecal marks. Territorial males marked with faeces more often, and with a smaller volume per defecation, than did juvenile males and females. Territorial males also defecated only on established dung middens along borders shared with other territorial males or on top of a female's urine and faeces. In contrast, juvenile males and females defecated randomly with regard to their location in territories. Territorial males with larger harems marked with faeces at higher rates and less volume than males with few or no females. This difference suggests that when males overmark female excretions they reduce the amount of faeces available for marking other preferred sites, such as along territory borders shared with other males. Dominant males with adult subordinates marked with faeces less often, and with a greater volume per mark, than males that defended territories without the aid of subordinates. Dominant males also reduced the volume of marks less as the number of females on their territory increased than did males without subordinates. Territories occupied by more than one adult male also were marked with faeces at higher rates, and with marks of greater volume, than territories held by single males. These results suggest that the presence of subordinate males reduced the demand on dominant males to regulate the volume and placement of faecal marks. Overall, these results suggest that territorial male oribi regulate their faecal marking behaviour in response to a limited supply of faeces. Copyright 1999 The Association for the Study of Animal Behaviour.     

扁颅蝠的扩散行为研究

我们于2002 ～ 2007 年在广西龙州县和宁明县采用标记重捕法对扁颅蝠的扩散行为进行研究, 共标记669 只(成体316 只,亚成体353 只;雌雄分别为293 只和376 只),重捕到139 只(重捕率20. 8% )。结果表明,大部分扁颅蝠雌雄后代在性成熟前发生扩散,其亚成体扩散率无性别差异(雄
性82.2% ,雌性66.7% ;P > 0.05)。对成年雌雄两性扩散率(雄性76.5% ,雌性58.5% )的分析亦未见性别差异(P > 0.05),但亚成体和成体合并结果显示雄蝠扩散率(80.7% )高于雌蝠(62.3% ,P < 0.01)。此外,我们还测量了扩散的距离,雄性后代的扩散距离(787. 5 ± 26.980 m,n = 37)比雌
性(517.4 ± 25.308 m,n = 24)远(P < 0. 01);在出现扩散的61 只后代中,仅有一只(0. 7% )雄性亚成体扩散到其它的竹林,其余个体均在出生竹林内的不同竹筒之间进行扩散。     

Scent-Marking of Giant Otter in the Southern Pantanal, Brazil

Giant otters live in social groups, consisting of a mating pair and one or two litters. Groups are territorial and mark their territories often with scent-marks. Our objectives were to evaluate the frequencies of marking and over-marking according to the social status of the individuals and to define the different postures used during the marking. We observed four groups, totaling 25 individuals (five alpha males, four alpha females, seven adult females, one adult male and eight juveniles) with group size ranging between four and 13 individuals. The study was conducted between July 2006 and July 2007 in the Vermelho River and in a stretch of the Miranda River, in the Southern Pantanal. We observed the groups for a total of 2006 min and recorded 95 events of marking totaling 84.9 min. Time spent marking varied between groups and ranged from 4.3 to 44.7 min. The alpha males marked more frequently (62% of marking events, 55 min) than the alpha females (17% of marking events, 13.6 min). Of the 59 events of scent-marking by the alpha males, 32 over-marked the marks of other individuals from the group. Of the 16 events of scent-marking of the alpha females, five over-marked that of other females from the same group. When scent-marking, alpha males used the 'stepping' posture most frequently (63%), then 'fore-paw rubbing' (24%), 'latrine use' (7%), and 'body rubbing' (6%). Alpha females used the 'stepping' posture most frequently (65%), then 'latrine use' (19%) and 'fore-paw rubbing' (12%), with only one event of 'body rubbing' observed during marking. Subordinate females used the 'stepping' posture (76%) and 'latrine use' (24%) during marking. Scent-marking can play many roles in mammals and for giant otters, and the main roles appear to be communication of social and sexual status and territorial defense.     

A Comparison of Spontaneous and Odor-induced Chin Marking in Male and Female Domestic Rabbits (Oryctolagus cuniculus domestica)

Chin marking by the European rabbit (Oryctolagus cuniculus) is one of the classic but still little understood examples of mammalian chemical communication. To investigate whether the sexes differ in performance of this behavior, we compared the frequency of spontaneous chinning and chinning in response to the chin marks of conspecifics in 20 intact male and 20 intact female chinchilla-breed rabbits, and in five gonadectomized animals of each sex. Contrary to the expectation of greater chinning activity in males, no significant sex differences were found. Frequencies of spontaneous chinning were similar in the two sexes, large and stable individual differences were observed in both, chinning increased in both when marks from unfamiliar conspecifics were present, and both directed chin marks to objects marked by conspecifics more than to unmarked objects. Individual chinning frequencies correlated positively with urination but not defecation in both sexes, and spontaneous and odor-induced chinning were significantly reduced both in castrated and ovariectomized animals. The findings suggest that chinning is an equally significant part of the communication system of male and female rabbits and that its expression may be regulated by similar olfactory, hormonal, and social mechanisms.     

Sex differences in scent marking in Propithecus edwardsi of Ranomafana National Park, Madagascar

In this study we compared the scent-marking rates of females with those of males. Specifically, we examined the ability of season, dominance status, and natal status to explain the frequency of scent marking in female sifakas living wild in Ranomafana National Park, Madagascar, and compared the results with those published for males [Pochron et al., American Journal of Primatology, in press]. We also sought to determine whether vulnerability to infanticide affects marking frequency in adults of either sex, and whether female reproductive status affects female marking behavior. We found that males marked at twice the rate of females, and like males, females in single-female groups marked at the highest rates. Dominant females and non-natal females marked at higher rates than did subordinate females and natal females, a pattern also seen in males. This suggests that scent marks may convey important information about status. Neither females nor males varied their marking frequency with the presence of vulnerable infants. Females did not alter marking frequency with reproductive state, and like males, they marked at higher rates in the period prior to the mating season than they did in the mating season itself. This implies that females may use scent marks more for intrasexual aggression or territoriality than for mate attraction.     

Male age, dominance, and mating success among rhesus macaques

Some previous primate studies have found a positive correlation between male dominance and mating success when data from subadult males were included in the analyses. The information in this paper suggests that an unconscious bias may have been introduced when data on subadult males were included because of the lower dominance rank of these animals. Data from a study of rhesus monkeys on Cayo Santiago showed that subadult males mated significantly less than adults. Because these monkeys are not fully mature, data on them should not be used in any test for correlation between adult male dominance and mating success. The only significant correlation found for adult male mating success was an inverse one with relation to age. Based on behavioral data young, fully adult males have the best chance of fathering offspring regardless of their dominance rank.     

An alternative to conventional insect marking procedures: detection of a protein mark on pink bollworm by ELISA*

Four experiments were conducted to examine the feasibility of marking pink bollworm, Pectinophora gossypiella (Saunders) with rabbit immunoglobulin G (IgG) protein for mark-release-recapture studies. Pink bollworm were internally marked by feeding larvae an enriched rabbit IgG diet or externally marked by submerging pupae and spraying adults. Individuals were then assayed for the presence of rabbit IgG by sandwich enzyme-linked immunosorbent assay (ELISA) using anti-rabbit IgG. The internal marker was retained in larvae and retained in prepupae and pupae, but not in adults. A second experiment showed that rabbit IgG was retained on adults that were externally marked as pupae. A third series of tests examined the feasibility of externally marking adults with rabbit IgG. Rabbit IgG was retained on externally marked adults for six days in the field. Protein was retained on marked moths in the laboratory after they were captured on and removed from sticky traps. Finally, laboratory tests showed that large groups of externally marked moths transferred rabbit IgG to unmarked moths, but individual males do not readily transfer the protein to unmarked females in small vials.     

The effect of external marking on the behaviour of the common pill woodlouse Armadillidium vulgare

Zoologists distinguish individual animals using marking techniques. Generally they test the potential influence of marking on survival only; the influence on behaviour is usually neglected. We evaluated the influence of two external marking techniques (nail polish and queen-bee marker) on the behaviour of common pill woodlouse, Armadillidium vulgare. The behaviour was examined from two points of view: (1) activity during 24 hours and (2) specific expressions of behaviour (exploring, feeding, resting and hiding) over a 24 hour period. We compared behaviour among woodlice marked with nail polish and queen-bee marker with the unmarked control group during a nine-day experiment. Although we did not find any influence of marking on survival, there was an evident influence on behaviour in most cases. Generally, in the groups of marked individuals of Armadillidium vulgare there were large differences observed against the control group in the overall activity. Activity of marked individuals was significantly reduced and they preferred hiding. The influence of polish and marker on the overall frequencies of behavioural categories was evident, mainly in feeding, resting and hiding. The influence on the frequency of exploring was significant in the polish marked group only.     

Marking live conifer pollen for long-distance dispersal experiments

Long-distance dispersal (LDD) theory requires a method for marking live LDD pollen. Such a method must complement more intensive sampling methods inclusive of molecular cytogenetics, proteomics and genomics. We developed a new method for marking live Pinus taeda pollen using two dyes, rhodamine 123 and aniline blue, dissolved in a sucrose solution. Marked and unmarked pollen were compared with respect to in vitro germination, storage, terminal velocity, and in vivo pollen tube penetration of ovules. We found that: (1) both types of marked pollen retained their capacity for germination, (2) both types of marked pollen had similar aerodynamic properties when compared to unmarked pollen controls, (3) marked pollen retained its germination capacity for 48 h, and (4) of the marked pollen, only the aniline-marked pollen penetrated ovules during pollination. Germination declined rapidly for both types of marked pollen after 48 h and before 37 days at -20°C storage, while unmarked pollen lots retained 93% germination at all stages. This method for marking live P. taeda pollen is feasible for tracing LDD pollen only if released and deposited within 48 h of dye treatment.     

Subadult male orangutan sociality and reproductive behavior at Tanjung Puting

During a four-year period at Tanjung Puting Reserve, Central Indonesian Borneo, subadult males were observed for 670.5 observation hours, 463 hours of which were as focal individuals. Subadult males were quite gregarious, participating in groupings for 40.9% of the time they were observed as targets. Subadult male sociality centered around females; 83% of the time subadult males spent in groupings was exclusively with females, as compared to 3% of contact time spent exclusively with other males. Much subadult male sociality can be understood in terms of male-male competition for females. Interactions between adult and subadult males were almost entirely determined by the presence or absence of females. Adult males were more belligerent when females were present. Twenty-two copulations or attempted copulations occurred during 16 subadult male-female encounters, two of which were consortships. The majority of subadult male copulations (86%) were resisted matings. Outside of consortship, resisted matings (or the first in a series of resisted matings or attempts) usually took place at encounter or shortly thereafter. Subadult males also surreptitiously followed adult males and their consorts. Subadults frequently located receptive females before adult males did but were replaced by adult males when these appeared. Subadult male reproductive strategy consisted of both sneak/“rape” and consort tactics with sneak/“rape” predominating.     

Scent marking by common volesMicrotus arvalis in the presence of a same-sex neighbour

Several vole species use scent marked runways radiating from their burrows for foraging and dispersion. These marks are probably used for social communication. This 4-day laboratory study investigated the environmental and social causations of marking inside pre-existing corridors in male and female common volesMicrotus arvalis (Pallas, 1778). Firstly I tested the novelty and the reinforcement hypotheses in isolated voles, predicting respectively a habituation or a continuous increase in mark deposition. I then confronted with each other two same-sex voles for two days to investigate the differences between males and females in the pattern of marks inside three corridors, one of which runs along the common partition with the neighbour. I tested the self-advertisement and territorial-defence hypotheses, respectively predicting in the presence of a neighbour either a similar marking between the three corridors or a greater marking in the corridor close to the neighbour than in the two other corridors. The results showed no habituation in marking, even in a familiar environment, confirming the reinforcement hypothesis. After the addition of a neighbour, only the females left more marks in the corridor that ran alongside the common border than in the two other corridors. The territorial-defence hypothesis was thus confirmed in (territorial) females while the self-advertisement was supported in (non-territorial) males. Finally, I tested the competitive-ability hypothesis in females, stating that the abundance of scent marks of an individual before a social interaction can predict its degree of intolerance in a future social interaction. The results from female pairs physically interacting for four days support the hypothesis.     

The Reproductive State of Female Voles Affects their Scent Marking Behavior and the Responses of Male Conspecifics to Such Marks

During the breeding season, the reproductive condition of female mammals changes. Females may or may not be sexually receptive. We conducted a series of experiments to determine whether reproductive condition of female meadow voles affects their scent marking behavior as well as the scent marking behavior of male conspecifics. In expt 1, females in postpartum estrus (PPE females) deposited more scent marks than females that were neither pregnant nor lactating (REF females) or ovariectomized females (OVX females). In expt 2, male voles scent marked more and deposited more over‐marks in areas marked by PPE females than by REF and OVX females. In expt 3, PPE females deposited more scent marks and over‐marks in areas marked by males than did females in the other reproductive states. The results of these experiments showed that male and female voles may vary in the number, type and location of scent marks they deposit in areas scented by particular conspecifics.     

Sociality in <Emphasis Type="Italic">Callithrix penicillata</Emphasis>: I. Intragroup Male Profile

We analyzed the social interactions and behavior of adult males from a group of black-tufted-ear marmosets (Callithrix penicillata) to determine their roles and hierarchy in the group and how their behavior fits within the predictions of monogamic or polyandric mating systems in callitrichines. We monitored 1 group of marmosets from February to October 2005 in central Brazil. We conducted focal subject samples with 20 predetermined behaviors for adult and subadult males and registered all occurrences of agonistic behavior, affiliative behavior, copulations, and alarm vocalizations. Moreover, we recorded the height in the vegetation and proximity to other individuals by the focal subject. Males exhibited no clear dominance hierarchy based on either behavioral data or patterns of scent marking. Copulation and grooming patterns showed a social bond between 1 of the males and the dominant female, suggesting him as the group’s putative breeding male, with no apparent competition for the position. There was no difference regarding other behaviors— alarm vocalization, infant carrying, and play—or the use of different vegetation strata among the males, and no indication of a specific role by the putative breeding male or any other male in the group. The presence of multiple males in marmoset groups and the behavioral profile generated in the current study suggest a mating system compatible with monogamy with helpers-at-the-nest structure.     

Latent multinomial models for extended batch-mark data

Batch marking is common and useful for many capture–recapture studies where individual marks cannot be applied due to various constraints such as timing, cost, or marking difficulty. When batch marks are used, observed data are not individual capture histories but a set of counts including the numbers of individuals first marked, marked individuals that are recaptured, and individuals captured but released without being marked (applicable to some studies) on each capture occasion. Fitting traditional capture–recapture models to such data requires one to identify all possible sets of capture–recapture histories that may lead to the observed data, which is computationally infeasible even for a small number of capture occasions. In this paper, we propose a latent multinomial model to deal with such data, where the observed vector of counts is a non-invertible linear transformation of a latent vector that follows a multinomial distribution depending on model parameters. The latent multinomial model can be fitted efficiently through a saddlepoint approximation based maximum likelihood approach. The model framework is very flexible and can be applied to data collected with different study designs. Simulation studies indicate that reliable estimation results are obtained for all parameters of the proposed model. We apply the model to analysis of golden mantella data collected using batch marks in Central Madagascar.     

Scent marking and mate choice in the prairie vole, Microtus ochrogaster

Scent marking is common among male and female rodents and might be used in male-male competition and as a mechanism for mate attraction. I tested the hypotheses that females would choose males based on their frequency and placement of scent marks, and that a female would advertise interest in a particular male by placing her scent marks on or near those of a preferred mating partner. In a series of experiments conducted with prairie voles, Microtus ochrogaster, females did not choose mates based on the frequency or placement of scent marks by males nor did they advertise their interest in a particular male through the frequency or placement of scent marks. The number of males chosen that scent-marked more than their opponents did not differ significantly between females exposed (11 of 15) and not exposed (10 of 15) to scents of males. Females exposed and not exposed to scents of males preferred seven of the same males that had scent-marked more than their opponents. When a third group of females was exposed to four times more scent of the less preferred than preferred males, they still chose the preferred males. Thus, the frequency and placement of scent marks by males were not used to assess males for mate choice nor did female prairie voles use scent to advertise their preference for a mating partner. In that scent marking is common in male and female mammals, scent quality might be more important than quantity in male-male competition and mate attraction.Copyright 2002 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved .     

Female transfer between one-male groups of proboscis monkey (<Emphasis Type="Italic">Nasalis larvatus</Emphasis>)

Successful or unsuccessful female transfers were observed seven times during a 32-month field study of proboscis monkeys (Nasalis larvatus) inhabiting a riverine forest along a tributary of the Kinabatangan River, Sabah, Malaysia. In all cases, the females voluntarily left their own groups and immediately joined with another one. When adult females tried to shift to other groups, adult males called them back to their own groups, but appeared to be indifferent to subadult females. When the adult females returned, the males never attacked the females physically, but instead often emitted herding sounds to them. One subadult female was repelled by a resident adult female. When one adult female transferred into a new one-male group, she left her behind son in an all-male group. The number of females often fluctuated in most study groups, with this fluctuation being more prominent among subadult females than adult females. It is likely that female transfer in proboscis monkeys is not a rare occurrence and that it is especially common among sub-adult females.