Pronounced inter-colony variation in the foraging ecology of Australasian gannets : influence of habitat differences

The predictability of prey due to oceanographic features can result in large aggregations of apex predators. Central place foragers, such as seabirds, are limited in their foraging duration and range during the breeding period, which can restrict their ability to reach such locations. Segregation by colony and sex can further restrict foraging range and may have direct implications for the foraging ecology of a species. In parts of its range, the Australasian gannet Morus serrator breeds in colonies of relatively close proximity and has recently been found to display sexual dimorphism. Two neighbouring breeding colonies in Bass Strait that experience divergent environmental conditions were investigated to determine whether these conditions or the sex of the individual are important variables influencing foraging behaviour in this species. GPS tracking and accelerometry were paired with stable isotope analysis to compare differences in foraging effort, habitat use and diet. Birds from Point Danger, a large colony located near a seasonally strong upwelling, travelled considerably further (77%) than birds from Pope's Eye, a small colony in a nutrient-poor embayment. However, within colonies no sexual differences in foraging effort were found. While the colonies did not overlap in foraging areas, a degree of sexual segregation was apparent within both colonies (Point Danger 46.3% overlap and Pope's Eye 73.7% overlap in home range). Furthermore, stable isotope analysis indicated birds from each colony fed at different trophic niches. This study reveals differences in habitat use and, consequently, dietary niches between and within neighbouring colonies.

Sexual segregation in habitat use is smaller than expected in a highly dimorphic marine predator, the southern sea lion

Sexual segregation in habitat use is widely reported in many taxa and can profoundly influence the distribution and behaviour of animals. However, our knowledge of the mechanisms driving sexual segregation is still in its infancy (particularly in marine taxa) and the influence of extrinsic factors in mediating the expression of sex differences in foraging behaviour is underdeveloped. Here, we combine data from biologging tags, with stable isotope analysis of vibrissae, to assess sexual segregation in southern sea lions (SSL) (Otaria flavescens) breeding at the Falkland Islands in the South Atlantic. We found evidence to support segregation, most notably in δ13C and δ15N values. However, in spite of extreme sexual size dimorphism and differing constraints related to female-only parental care, adult male and adult female SSL overlapped considerably in isotopic niches and foraging area, and shared similar foraging trip characteristics (such as distance and duration). This is in contrast to SSL breeding in Argentina, where prior studies report sexual differences in foraging locations and foraging trip characteristics. We posit that sexual segregation in SSL is influenced by habitat availability (defined here as the width of the Patagonian Shelf) and individual foraging preferences, rather than commonly invoked individual-based limiting factors per se.

Prolonged and flexible primary moult overlaps extensively with breeding in beach-nesting Hooded Plovers Thinornis rubricollis

We present the first report of complete overlap of breeding and moult in a shorebird. In southeastern Australia, Hooded Plovers Thinornis rubricollis spend their entire lives on oceanic beaches, where they exhibit biparental care. Population moult encompassed the 6-month breeding season. Moult timing was estimated using the Underhill-Zucchini method for Type 2 data with a power transformation to accommodate sexual differences in rates of moult progression in the early and late stages of moult. Average moult durations were long in females (170.3 ± 14.2 days), and even longer in males (210.3 ± 13.5 days). Breeding status was known for most birds in our samples, and many active breeders (especially males) were also growing primaries. Females delayed the onset of primary moult but were able to increase the speed of moult and continue breeding, completing moult at about the same time as males. The mechanism by which this was achieved appeared to be flexibility in moult sequence. All moult formulae fell on one of two linked moult sequences, one faster than the other. The slower sequence had fewer feathers growing concurrently and also had formulae indicating suspended moults. Switching between sequences via common formulae is possible at many points during the moult cycle, and three of 12 recaptures were confirmed to have switched sequences in the same moult season. Hooded Plovers thus have a prolonged primary moult with the flexibility to change their rate of moult; this may facilitate high levels of replacement clutches that are associated with passive nest defence and low reproductive success. © 2014 British Ornithologists' Union.

Extended supervision of sexual offenders in Australia and New Zealand : differences in implementation across jurisdictions

Australia and New Zealand have joined the movement of many Western societies in recent years to address a perceived gap in public safety by passing legislation allowing for extended supervision of sex offenders in the community after their release from prison. The Australian State of Victoria passed a law similar to that of New Zealand, and both laws have now been in effect for a similar period of time. Yet despite having comparable laws and approximately comparable base populations, there have been 145 extended supervision orders imposed in New Zealand and 20 such orders in Victoria. This article examines the differences in implementation and the underlying procedures used in the two jurisdictions to understand these very different outcomes. Implications for professional practice, ethics, public safety, and policy development are discussed.

Individual differences in affective responses to violence and sexual violence

The thesis aimed to identify and compare individual differences in anger related affective responses upon exposure to neutral, violent and sexually violent film. The findings revealed that both graphic and non-graphic sexually violent film content may have a stronger impact on viewers' anger levels than exposure to standard violent film. The portfolio examined in four case studies the utility of the Violence Risk Scale when seeking to identify factors associated with risk of violent recidivism and subsequent treatment targets for intellectually disabled offenders . Treatment indications must consider the impaired cognitive and adaptive abilities and the difficulties inherent in modifying the behavioural characteristics of intellectually disabled offenders.

Explaining the gender differences inperceptions of child sexual abuse

The aim of the thesis was to understand how gender, empathy and myth endorsement impact on jurors' perceptions of child sexual abuse victims.

Ontogenic differences in sexual size dimorphism across four plover populations

Sexual size dimorphism (SSD) among adults is commonly observed in animals and is considered to be adaptive. However, the ontogenic emergence of SSD, i.e. the timing of divergence in body size between males and females, has only recently received attention. It is widely acknowledged that the ontogeny of SSD may differ between species, but it remains unclear how variable the ontogeny of SSD is within species. Kentish Plovers Charadrius alexandrinus and Snowy Plovers C. nivosus are closely related wader species that exhibit similar, moderate (c. 4%), male-biased adult SSD. To assess when SSD emerges we recorded tarsus length variation among 759 offspring in four populations of these species. Tarsus length of chicks was measured on the day of hatching and up to three times on recapture before fledging. In one population (Mexico, Snowy Plovers), males and females differed in size from the day of hatching, whereas growth rates differed between the sexes in two populations (Turkey and United Arab Emirates, both Kentish Plovers). In contrast, a fourth population (Cape Verde, Kentish Plovers) showed no significant SSD in juveniles. Our results suggest that adult SSD can emerge at different stages of development (prenatal, postnatal and post-juvenile) in different populations of the same species. We discuss the proximate mechanisms that may underlie these developmental differences.

Self-perceived sexual attractiveness: differences and contributing factors across gender and sexual orientation

This thesis explored factors associated with feeling sexually attractive among men and women across different sexual orientations. A combination of physical and non-physical traits were found to predict positive self-ratings of sexual attractiveness, and feeling sexy was found to positively contribute to various aspects of an individual’s sexuality.

Conceptualization of the sexual response models in men: are there differences between sexually functional and dysfunctional men?

Introduction: Research to validate models of sexual response empirically in men with and without sexual dysfunction (MSD), as currently defined, is limited.Aim: To explore the extent to which the traditional linear or the Basson circular model best represents male sexual response for men with MSD and sexually functional men.Methods: In total, 573 men completed an online questionnaire to assess sexual function and aspects of the models of sexual response. In total, 42.2% of men (242) were sexually functional, and 57.8% (331) had at least one MSD. Models were built and tested using bootstrapping and structural equation modeling.Main Outcome Measures: Fit of models for men with and without MSD.Results: The linear model and the initial circular model were a poor fit for men with and without MSD. A modified version of the circular model demonstrated adequate fit for the two groups and showed important interactions between psychological factors and sexual response for men with and without MSD.Conclusion: Male sexual response was not represented by the linear model for men with or without MSD, excluding possible healthy responsive desire. The circular model provided a better fit for the two groups of men but demonstrated that the relations between psychological factors and phases of sexual response were different for men with and without MSD as currently defined.

Relationship between men's and women's body image and their psychological, social, and sexual functioning

This study was designed to examine the relationships between different aspects of body image and psychological, social, and sexual functioning throughout adulthood. The respondents were 211 men and 226 women (age range 18–86 years; mean = 42.26). Respondents completed measures of self-rated attractiveness, body satisfaction, body image importance, body image behaviors, appearance comparison, social physique anxiety, self-esteem, depression, anxiety, and social and sexual functioning. Body image was associated with self-esteem for all groups, but was unrelated to other aspects of psychological, social, and sexual functioning. There were some exceptions; a disturbance in body image was related to problematic social and sexual functioning among middle-aged men and to depression and anxiety symptoms in late adulthood among men and women. Middle-aged men who presented with the type of body image disturbance typical of women were more likely to have impaired interpersonal functioning. These results demonstrate that social aspects of body image appear to be important in understanding psychological functioning in later life.

Correlates of sexual assault in a sample of male African American crack cocaine users

Although numerous studies have reported an association between substance use and sexual assault, little is known about the impact of sexual assault on male African American crack cocaine users. This study found that from a sample of 137 respondents from Houston, Texas, one-third reported having been sexually assaulted at least once during their lifetime. Respondents who reported sexual assault were using cocaine more often and were more likely to be physically dependent on drugs and to report greater numbers of physical health problems due to their drug use. However, no differences were identified in respect of reported mental health problems, or problems with family, friends or the workplace associated with drug use. The findings suggest further research as to the impact of sexual assault on male crack cocaine users is warranted and that clinical staff working with male substance users require some awareness of the impacts of sexual assault.

The effect of mood on opposite-sex judgments of males' commitment and females sexual intent

Gender differences in perceptions of sexual intent and commitment have been the subject of formal and informal inquiry for considerable time. One evolutionary theory, Error Management Theory (EMT), predicts that opposite-sex perceptions of female sexual intent and male commitment intent reflect intrinsic biases that minimize gender-specific evolutionary costs. The results supporting these hypotheses were obtained from subjects regardless of mood. We hypothesized that mood would influence ratings of sexual and commitment intent. Sixty participants (30 males, 30 females) were recruited and exposed to a positive and negative mood condition in counterbalanced groups using video stimuli. Preliminary analyses found an unexpected effect of order of mood induction, necessitating separate analyses of the Positive-Negative (PN) and Negative-Positive (NP) groups. Contrary to the original study, there were no gender effects. Positive moods led to increased ratings of both sexual and commitment intent across genders. Further, negative to positive mood-change was associated with significantly increased ratings. Both males and females attributed significantly higher sexual intent to same-sex rivals than themselves, but only males assessed themselves as having significantly higher commitment intent than same-sex rivals. The EMT model may require adaptation to acknowledge effects of variables such as mood on its predictions of gender-specific biases.

Sexual segregation in western grey kangaroos: testing alternative evolutionary hypotheses

In sexually dimorphic ungulates, sexual segregation is hypothesized to have evolved because of sex-specific differences in body size and/or reproductive strategies. We tested these alternative hypotheses in kangaroos, which are ecological analogues of ungulates. Kangaroos exhibit a wide range of body sizes, particularly among mature males, and so the effects of body size and sex can be distinguished. We tested predictions derived from these hypotheses by comparing the distribution of three sex–sex size classes of western grey kangaroos Macropus fuliginosus, in different habitats, and the composition of groups of kangaroos, across seasons. In accordance with the predation risk-reproductive strategy hypothesis, during the non-breeding season, females, which were more susceptible to predation than larger males, and were accompanied by vulnerable young-at-foot, were over-represented in secure habitats. Large males, which were essentially immune to predation, occurred more often than expected in nutrient-rich habitat, and small males, which faced competing demands of predator avoidance and feeding, were intermediate between females and large males in their distribution across habitats. During the breeding season, females continued to be over-represented in secure habitats when their newly emerged pouch young were most vulnerable to predation. All males occupied these same habitats to maximize their chances of securing mates. Consistent with the social hypotheses, groups composed of individuals of the same sex, irrespective of body size, were over-represented in the population during the non-breeding season, while during the breeding season all males sought females so that mixed-sex groups predominated. These results indicate that body size and reproductive strategies are both important, yet independent, factors influencing segregation in western grey kangaroos.

Effect of deer velvet on sexual function in men and their partners: a double-blind, placebo-controlled study

The use of alternative medicines and herbal remedies is an increasing trend in Western societies. For years, people have taken products made of deer velvet for their alleged beneficial effects on sexual function. There has been no scientific investigation of the effects of deer velvet powder on the sexual functioning of human males. This study investigated sexual function in men during a 12-week double-blind, placebo-controlled trial of deer velvet. Thirty-two volunteer male participants, aged 45–65 years, and their partners, were randomly assigned to either the deer velvet or placebo study group. The males took capsules containing ground deer velvet or placebo everyday for 12 weeks. Two sexual function questionnaires (the International Index of Erectile Function and the Brief Index of Sexual Function for Women) used at pre- and posttreatment assessed changes in sexual functioning in males and their partners. Blood tests at baseline, and end of study, determined levels of sex-related hormones in male participants. There were no significant differences in the sexual behavior of the men taking deer velvet compared with the men taking placebo capsules. There were no significant hormone changes from baseline to the end of the study in either group of men. We conclude that in normal males there was no advantage in taking deer velvet to enhance sexual function. All alternative health products or nutritional supplements should be subjected to randomized placebo-controlled trials to determine efficacy.

Are aspects of study design associated with the reported prevalence of female sexual difficulties?

Objective: To investigate associations between the prevalence of sexual  difficulties reported in published studies and design features of those studies to determine if differences in design contribute to variation in prevalence estimates.
Design: Systematic review, multivariate analysis.
Setting: Studies published internationally in English.
Patient(s): Not applicable.
Intervention(s): None.
Main Outcome Measure(s): Prevalence estimates of difficulty with desire, arousal, orgasm, and sexual pain reported in published studies.
Result(s): Our systematic literature search identified 1,380 publications. Fifty-five studies met our inclusion criteria (reporting prevalence, sample size and response rate, sample size greater than 100, not clinic based). Reported prevalence of sexual difficulty varied across studies (up to tenfold). Eleven aspects of research conduct in these studies were included in our multivariate analysis as explanatory variables. Five aspects of study design and conduct (data collection procedures, inclusion criteria, duration of sexual difficulty recorded, sample size, and response rate) were associated with the reported prevalence of at least one type of sexual difficulty independently of likely predictors of true variation in prevalence: study location, study year, and age range of participants.
Conclusion(s): This review provides evidence that study design may influence reported prevalence estimates of female sexual difficulties and contribute to the wide variation in published estimates.