Pup production and population trends of the Australian fur seal (Arctocephalus pusillus doriferus)

We estimated the number of live Australian fur seal pups using capture-markresights, direct ground counts, or aerial photography at all breeding sites following the pupping season of November-December 2002. Pups were recorded at 17 locations; nine previously known colony sites, one newly recognized colony and seven haul-out sites where pups are occasionally born. In order of size, the colonies were Lady Julia Percy Island (5,899 pups), Seal Rocks (4,882), The Skerries (2,486), Judgment Rocks (2,427), Kanowna Island (2,301), Moriarty Rocks (1,007), Reid Rocks (384), West Moncoeur Island (257), and Tenth Island (124). The newly recognized site was Rag Island, in the Cliffy Group, where we recorded 30 pups. We also recorded pups at the following haul-out sites: Cape Bridge-water (7 pups), Bull Rock (7), Wright Rock (5), Twin Islet (1), The Friars (1), He des Phoques (1), and Montague Island (1). In total, we estimate there were 19,819 (SE = 163) live pups at the time of the counts. We discuss trends in pup numbers and derive current population estimates for the Australian fur seal.

Federally funded aged care provision in regional Victoria : Examining current provision and estimating future infrastructure requirements using existing population-based benchmarks

The following paper examines federally accredited and funded aged care provision in regional Victoria. Benchmarks that have been set by the Australian Department of Health and Ageing, are used to measure and compare the relative number of high and low level aged care positions and Community Aged Care Packages in six regional Victorian centres.
Using population forecasts, the additional aged care positions that each centre will require to meet the provision benchmarks in the year 2021 have been estimated. These figures are then translated into infrastructure requirements for the regional Victorian city of Greater Bendigo. This is done by surveying Greater Bendigo’s existing residential aged care facilities. Strategies for the provision of additional high and low level residential aged care infrastructure are explored using a matrix governed by size and configuration. Variations in these two aspects are shown to affect the location options for future facilities in Greater Bendigo. The implications of the benchmarks are also investigated in terms of facilities for the provision of Community Aged Care Packages.
The research is funded by a double ARC APAI grant between the Built Environment Research Group at Deakin University, The Centre for Sustainable Regional Centres at La Trobe University, the City of Greater Bendigo and the City of Warrnambool.

Sociocultural factors relating to Tongans' and Indigenous Fijians' patterns of eating, physical activity and body size

This paper reviews literature between 1974 and 2007 that addresses the impact of sociocultural factors on reported patterns of eating, physical activity (activity) and body size of Tongans and indigenous Fijians (Fijians) in their countries of origin. There have been changes in diet (more imported and fewer traditional foods), activity (reduced, especially in urban settings), residence (rural-urban shift) and body size (increased obesity and at a younger age). The prevalence of overweight/obesity in Tongans and Fijians has increased rapidly over the last two decades and remains among the highest in the world (>80% in Tonga; >40% in Fiji), with more females reported to be obese than males. The few studies that investigated sociocultural influences on patterns of eating, activity and/or body size in this population have examined the impact of hierarchical organisation, rank and status (sex, seniority), values (respect, care, co-operation) and/or role expectations. It is important to examine how sociocultural factors influence eating, activity and body size in order to i) establish factors that promote or protect against obesity, ii) inform culturally-appropriate interventions to promote healthy lifestyles and body size, and iii) halt the obesity epidemic, especially in cultural groups with a high prevalence of obesity. There is an urgent need for more systematic investigations of key sociocultural factors, whilst taking into account the complex interplay between sociocultural factors, behaviours and other influences (historical; socioeconomic; policy; external global influences; physical environment).

Urban living and obesity : is it independent of its population and lifestyle characteristics?

OBJECTIVES: Living in an urban area influences obesity. However, little is known about whether this relationship is truly independent of, or merely mediated through, the demographic, socio-economic and lifestyle characteristics of urban populations. We aimed to identify and quantify the magnitude of this relationship in a Sri Lankan population.

METHODS: Cross-sectional study of adults aged 20-64 years representing the urban (n = 770) and rural (n = 630) populations, in the district of Colombo in 2004. Obesity was measured as a continuous variable using body mass index (BMI). Demographic, socio-economic and lifestyle factors were assessed. Gender-specific multivariable regression models were developed to quantify the independent effect of urban/ rural living and other variables on increased BMI.

RESULTS: The BMI (mean; 95% confidence interval) differed significantly between urban (men: 23.3; 22.8-23.8; women: 24.2; 23.7-24.7) and rural (men: 22.3; 21.9-22.7; women: 23.2; 22.7-23.7) sectors (P < 0.01). The observed association remained stable independently of all other variables in the regression models among both men (coefficient = 0.64) and women (coefficient = 0.95). These coefficients equated to 2.2 kg weight for the average man and 1.7 kg for the average woman. Other independent associations of BMI were with income (coefficient = 1.74), marital status (1.48), meal size (1.53) and religion (1.20) among men, and with age (0.87), marital status (2.25) and physical activity (0.96) among women.

CONCLUSIONS: Urban living is associated with obesity independently of most other demographic, socio-economic and lifestyle characteristics of the population. Targeting urban populations may be useful for consideration when developing strategies to reduce the prevalence of obesity.

Population dynamics of the infaunal bivalve, Soletellina alba

The population dynamics of the infaunal bivalve Soletellina alba was investigated at three sites situated within close proximity to the mouth of the Hopkins River estuary. The initial study design was planned to examine the importance of winter flooding to the persistence of this bivalve mollusc within the Hopkins estuary, since mass mortalities have been observed during previous years coincident with periods of winter flooding. Unfortunately, the climatic conditions experienced during this study were atypical compared to the long-term average, so detailed sampling was limited to two, unanticipated, non-flood years rather than two, highly anticipated, flood years. This hampered my ability to conduct complete tests of the importance of winter flooding. Patterns of river discharge and the frequency and duration of mouth opening and closing differed greatly from that expected. Unexpectedly, periods of mouth closure were not always associated with periods of minimal river discharge; low salinities were another unexpected result during an extended period of mouth closure during 1998. As expected, salinities varied considerably with increasing water depth when the estuary mouth was open. Mouth closure lead to salinities becoming more uniform between water depths but hypoxic and anoxic conditions became evident via stratification in the water column at 1 m below the Australian Height Datum (AHD). Other than trends associated with increased water depth, significant variation was not evident between measurements of salinity taken from three sites within close proximity of the estuary mouth (approximately 500 m), or during changes in tide. The most pertinent anomaly was the absence of winter flooding. The distribution and abundance of juvenile and adult S. alba was variable across all Dates, Sites and Channel elevations (i.e. water depths) sampled during this study. An experimental test comparing the recruitment of juveniles at different channel elevations and in sediments of varying particle size was conducted during an exceptionally successful period of recruitment during 1999. The results of these tests showed that recruitment was greatest at the shallowest channel elevation used, and there was little evidence that sediment particle size influenced recruitment. In contrast to 1999, recruitment during 1997 or 1998 was extremely poor. Growth rates were monitored using tagged individuals held in caged and uncaged plots, which revealed that growth was highly variable among individuals, but not between Sites. These tests also revealed that growth was negligible during the colder, winter months, and that the fastest growing individuals were capable of growing 0.2 mm/day. Mixed results were obtained for tests of potential cage artifacts and the influence of handling. Caging and differing amounts of handling did not appear to influence growth, but there was evidence that cages and handling influenced bivalve condition and number of mortalities. These direct tests appeared to be the most appropriate method for determining growth rates of this species, since attempts to analyse length-frequency data were made difficult by the apparent convergence of cohorts, and shell aging is difficult due to the thin, fragile nature of the shell. As expected, mass mortalities were observed during the flood of 1996, but not during the two non-flood years of 1997 and 1998. There were, however, some considerable declines in abundances at some channel elevations during the two non-flood years. However, these declines were attributable to the complete disappearance of individuals, rather than the sudden presence of numerous, recently dead individuals that typify observed declines during winter flooding. The complete disappearance of individuals suggest that S. alba may be capable of post-settlement emigration, or that they were consumed by an unknown predator. Salinity tolerance tests showed that bivalves exposed to low salinities (≤6 ppt), exhibited poorer condition and took longer to re-burrow into sediments than those exposed to greater salinities (≥14 ppt), while death of bivalves exposed to salinities ≤1 ppt occurred after 8 days of exposure. These tests provide evidence that low salinities are probably the principal cause of mass mortalities during winter flooding, although the interaction between salinity, temperature and turbidity also deserve consideration. The results of this study indicate that certain aspects of winter flooding, especially salinity, are responsible for the mass mortalities of S. alba rather than the result of a short-lived life history. I hypothesise that the survival of very young juveniles (between 0.5 and 1 mm shell length) and rapid growth rates are important features of the life history of S. alba that explain its successful persistence within the Hopkins River estuary. The rapid rates of growth suggest that it may be possible for juveniles that survive winter flooding to grow, reach sexual maturity, and reproduce before the onset of the next flood event. Unfortunately, the increased survivorship of juveniles during periods of winter flooding was not demonstrated by this study because of the absence of winter flooding and also relatively poor recruitment. It is highly likely that this species is capable of completing it entire life cycle within the estuary since the absence of other nearby populations, together with periods of mouth closure, are likely to greatly limit the potential contribution made by larvae entering from the surrounding marine environment. This study has added considerably to our knowledge of how infauna cope with life in the intermittently closing estuaries that typify semi-arid coastlines in the Southern Hemisphere.

Within-population variation in ejaculate characteristics in a prolonged breeder, Peron's tree frog, Litoria peronii

Sperm number is often a good predictor of success in sperm competition; however, it has become increasingly clear that, for some species, variation in probability of paternity cannot be explained by sperm number alone. Intraspecific variation in ejaculate characteristics, such as the number of viable sperm and sperm longevity, may play an equally important role in determining fertilization success. Here, we assess variation among ejaculates in three factors that may contribute to fertilization success (number of sperm per ejaculate, viability, and longevity), in a population of Peron’s tree frog (Litoria peronii). We detected large variation among males in the number of sperm per ejaculate and the proportion of viable sperm within ejaculates, which could not be explained by variation in either male size or body condition. However, the proportion of viable sperm released by males increased over the season. Finally, we assessed sperm longevity (proportion viable sperm determined using a dual-fluorochrome vital dye) at two different temperatures. At 23°C, on average, 75% of sperm remained viable after 2 h, but there were significant differences amongst males with the percentage of viable sperm ranging from 43% to 95%. For sperm incubated at 4°C, ejaculates varied fivefold in sperm longevity with some males having 50% viable sperm after 5 days. Our data suggest that ejaculate characteristics (sperm number, viability, and longevity) vary widely in Peron’s tree frog and may therefore play an important role in determining siring success both in the presence and absence of sperm competition. We discuss the results in relation to selection on ejaculate traits via natural and sexual selection in this and other amphibians.

Population structure and life history characteristics of euastacus bispinosus and cherax destructor (Parastacidae) in the Grampians National Park, Australia

Despite being the most widely distributed and cultured freshwater crayfish species in Australia, relatively little is known about the ecology of Cherax destructor outside of captivity. Similarly, few ecological studies have been conducted on the large and threatened stream dwelling Australian freshwater crayfish Euastacus bispinosus. A series of seasonal sampling surveys over two years investigated the population structure, life history and reproductive timing of C. destructor in fire dam habitats, and of E. bispinosus in channel (stream) habitats, in the Grampians National Park in south-west Victoria, Australia. Cherax destructor individuals in the largest size class (50 – 59.95 mm OCL) were not abundant during the study, while those belonging to the 0 – 9.95 mm OCL size class were more frequent in summer than at other times of year, suggesting synchronous recruitment in fire dam habitats. Individuals in the reproductively active mid-size classes were also frequent in summer. For E. bispinosus, sex ratios in spring always favoured females, although there were no clear trends for other times of year. Gravid E. bispinosus females were found in winter and spring throughout the study, and were sexually mature at a smaller size than has previously been reported.

Diet quality in bipolar disorder in a population-based sample of women

Background : Recent epidemiological evidence has indicated a role for diet quality in unipolar depressive illness. This study examined the association between diet quality and bipolar disorder (BD) in an epidemiological cohort of randomly selected, population-based women aged 20–93 years.

Methods : An a priori diet quality score was derived from food frequency questionnaire data, a factor analysis identified habitual dietary patterns and glycemic load was assessed. Mental health was assessed using the SCID-I/NP.

Results : BD was identified in 23 women and there were 691 participants with no history of psychopathology. Compared to those with no psychopathology, those with BD had a higher glycemic load (p = 0.06) and higher scores on a ‘western’ dietary factor (p = 0.03) and the ‘modern’ dietary factor (p = 0.02). For each standard deviation increase in a ‘western’ and ‘modern’ dietary pattern and glycemic load, the odds ratios for BD were increased (‘western’ OR = 1.88, 95% CI 1.33–2.65; ‘modern’ OR = 1.72, 95% CI 1.14–2.39; GL OR = 1.56, 95% CI 1.13–2.14). Conversely, a ‘traditional’ dietary pattern was associated with reduced odds for BD (OR = 0.53 95% CI 0.32–0.89) after adjustments for overall energy intake.

Limitations : The small sample size did not allow for multivariate analyses and the cross-sectional study design precludes any determinations regarding the direction of the relationships between diet quality and BD.

Conclusion : These data are largely concordant with results from dietary studies in unipolar depression. However, clinical recommendations cannot be made until the direction of the relationship between diet quality and BD is determined. Longitudinal studies are warranted.

Population genetics of the spotted seahorse (Hippocampus kuda) in Thai waters : implications for conservation

A population genetics approach was used to investigate the genetic diversity of the spotted seahorse (Hippocampus kuda) in Thai waters; specifically, the degree of genetic differentiation and species evolution was inferred from sequence analysis of 353 bp of the mitochondrial (mt)DNA control region. The data were then used to identify discrete populations in Thai waters for effective conservation and management. Spotted seahorses were collected from 4 regions on the east and west coasts of the Gulf of Thailand and a geographically separated region in the Andaman Sea. Of the 101 mtDNA sequences analyzed, 7 haplotypes were identified, 5 of which were shared among individuals from the east and west coasts of the Gulf of Thailand. The remaining haplotypes were restricted to individuals from the Andaman Sea. Nucleotide and haplotype diversities were similar within the Gulf of Thailand samples, whereas diversity was lower in the Andaman Sea sample. Genetic differentiation appeared between pairs of samples from the Gulf of Thailand and Andaman Sea (FST, p < 0.0001). A large genetic variance appeared among the 2 population groups (94.46%, ΦCT = 0.94464, p < 0.01). A Neighbor-joining tree indicated that individuals from the Gulf of Thailand and Andaman Sea formed 2 phylogenetically distinct groups, which were segregated into different population-based clades. While results reported here indicate that populations from the Gulf of Thailand and Andaman Sea should be treated as separate conservation units, a larger sample size from the Andaman Sea is required to confirm this genetic partitioning and low level of diversity observed in the present study.

Range size-abundance relationships in Australian passerines

Aim  To investigate the relationship between geographical range size and abundance (population density) in Australian passerines.
Location  Australia (including Tasmania).
Methods   We analysed the relationship between range size and local abundance for 272 species of Australian passerines, across the whole order and within families. We measured abundance as mean and maximum abundance, and used a phylogenetic generalized least-squares regression method within a maximum-likelihood framework to control for effects of phylogeny. We also analysed the relationship within seven different habitat types.
Results  There was no correlation between range size and abundance for the whole set of species across all habitats. Analyses within families revealed some strong correlations but showed no consistent pattern. Likewise we found little evidence for any relationship or conflicting patterns in different habitats, except that woodland/forest habitat species exhibit a negative correlation between mean abundance and range size, whilst species in urban habitats exhibit a significant positive relationship between maximum abundance and range size. Despite the general lack of correlation, the raw data plots of range size and abundance in this study occupied a triangular space, with narrowly distributed species exhibiting a greater variation in abundances than widely distributed species. However, using a null model analysis, we demonstrate that this was due to a statistical artefact generated by the frequency distributions for the individual variables.
Conclusions   We find no evidence for a positive range size-abundance relationship among Australian passerines. This absence of a relationship cannot be explained by any conflicting effects introduced by comparing across different habitats, nor is it explained by the fact that large proportions of Australia are arid. We speculate that the considerable isolation and evolutionary age of Australian passerines may be an explanatory factor.

Pheromone production, male abundance, body size, and the evolution of elaborate antennae in moths

The males of some species of moths possess elaborate feathery antennae. It is widely assumed that these striking morphological features have evolved through selection for males with greater sensitivity to the female sex pheromone, which is typically released in minute quantities. Accordingly, females of species in which males have elaborate (i.e., pectinate, bipectinate, or quadripectinate) antennae should produce the smallest quantities of pheromone. Alternatively, antennal morphology may be associated with the chemical properties of the pheromone components, with elaborate antennae being associated with pheromones that diffuse more quickly (i.e., have lower molecular weights). Finally, antennal morphology may reflect population structure, with low population abundance selecting for higher sensitivity and hence more elaborate antennae. We conducted a phylogenetic comparative analysis to test these explanations using pheromone chemical data and trapping data for 152 moth species. Elaborate antennae are associated with larger body size (longer forewing length), which suggests a biological cost that smaller moth species cannot bear. Body size is also positively correlated with pheromone titre and negatively correlated with population abundance (estimated by male abundance). Removing the effects of body size revealed no association between the shape of antennae and either pheromone titre, male abundance, or mean molecular weight of the pheromone components. However, among species with elaborate antennae, longer antennae were typically associated with lower male abundances and pheromone compounds with lower molecular weight, suggesting that male distribution and a more rapidly diffusing female sex pheromone may influence the size but not the general shape of male antennae.

Vector activity and propagule size affect dispersal potential by vertebrates

Many small organisms in various life stages can be transported in the digestive system of larger vertebrates, a process known as endozoochory. Potential dispersal distances of these “propagules” are generally calculated after monitoring retrieval in experiments with resting vector animals. We argue that vectors in natural situations will be actively moving during effective transport rather than resting. We here test for the first time how physical activity of a vector animal might affect its dispersal efficiency. We compared digestive characteristics between swimming, wading (i.e. resting in water) and isolation (i.e. resting in a cage) mallards (Anas platyrhynchos). We fed plastic markers and aquatic gastropods, and monitored retrieval and survival of these propagules in the droppings over 24 h. Over a period of 5 h of swimming, mallards excreted 1.5 times more markers than when wading and 2.3 times more markers than isolation birds, the pattern being reversed over the subsequent period of monitoring where all birds were resting. Retention times of markers were shortened for approximately 1 h for swimming, and 0.5 h for wading birds. Shorter retention times imply higher survival of propagules at increased vector activity. However, digestive intensity measured directly by retrieval of snail shells was not a straightforward function of level of activity. Increased marker size had a negative effect on discharge rate. Our experiment indicates that previous estimates of propagule dispersal distances based on resting animals are overestimated, while propagule survival seems underestimated. These findings have implications for the dispersal of invasive species, meta-population structures and long distance colonization events.

Satellite tracking large numbers of individuals to infer population level dispersal and core areas for the protection of an endangered species

Aim: Tracking the dispersal patterns and habitat use of migratory species is necessary to delineate optimal areas for protection, with large sample sizes being more representative of the population. Here, we examine the dispersal patterns of a key Mediterranean loggerhead turtle (Caretta caretta) breeding population to identify priority foraging sites for protection. Location: Zakynthos Island, Greece and the wider Mediterranean. Method: We examined the dispersal patterns and foraging sites of 75 adult loggerheads (n = 38 males and 37 females) tracked from the breeding area of Zakynthos Island (Greece) from 2004 to 2011. We then combined our data with published sea turtle literature to identify key foraging sites for protection. Results: While both males and females exhibited similar dispersal patterns, about 25% males remained < 100 km of Zakynthos, whereas all females (except one) migrated > 200 km. Integration of our data with the wider literature isolated 10 core sites in proximity to existing protected areas, which could potentially protect 64% of the Zakynthos population, while five sites support individuals from at least 10 other loggerhead breeding populations. Main conclusions: Due to the widespread availability of neritic foraging grounds across the Mediterranean, sea turtles from Zakynthos exhibit disparate dispersal patterns. However, protecting only a few objectively defined important sites can encompass a large proportion of the foraging areas used and hence have considerable conservation benefit.

A comparison of Australian rural and metropolitan cardiovascular risk and mortality: the Greater Green Triangle and North West Adelaide population surveys

Objectives:
Cardiovascular (CVD) mortality disparities between rural/regional and urban-dwelling residents of Australia are persistent. Unavailability of biomedical CVD risk factor data has, until now, limited efforts to understand the causes of the disparity. This study aimed to further investigate such disparities.

Reproductive investment and optimum clutch size of Loggerhead Sea Turtles (Caretta caretta)

(1) Data for loggerhead turtles (Caretta caretta L.) nesting on the Greek island of Cephalonia were used to develop a model which predicted the optimum clutch size. (2) There was a positive linear relationship between the number of clutches into which eggs could be divided and the total time spent by a nesting turtle on the beach, and hence a negative relationship between the time invested on the beach per egg and clutch size. (3) A previous study indicated that energy expenditure for nesting turtles on land is very high, so there may be a selective pressure to maximize clutch size in order to minimize the energy expended per egg laid. As there appeared to be no counterselective pressures favouring small clutches, clutch size should be constrained by a female's egg-carryingc apacity,w hich in turn could be expected to be related to her body size. Hence, a positive relationship between clutch size and body size was predicted, and was found in the population under study.