The diet of powerful owls (Ninox strenua) and prey availability in a continuum of habitats from disturbed urban fringe to protected forest environments in south-eastern Australia

This study investigates the diet of six breeding pairs of powerful owls in the Yarra Valley Corridor in Victoria, Australia, and compares prey consumption with prey availability. The six sites represent a continuum of habitats, ranging from urban Melbourne, through the urban fringe interface to a more forested landscape. We found that powerful owls in the Yarra Valley Corridor are reliant almost exclusively on arboreal marsupial prey as their preferred diet, with 99% of their overall diet comprising four arboreal marsupial species. These four species (the common ringtail possum, common brushtail possum, sugar glider and greater glider) were also the most abundant species observed while spotlighting; however, their abundance varied along the continuum. There was a strong positive relationship with the presence of these species in the diet and their site-specific availability, indicating that the powerful owl is a generalist hunter, preying on the most available prey at a given site and in a given season. This study suggests that food resources are high in these disturbed urban fringe sites and it is unlikely that food availability in urban environments will limit the potential survival of urban powerful owls.

Food and activity in out of school hours care in Victoria

Objective: To describe characteristics of the Victorian out of school hours care (OSHC) sector to assess its potential role in promoting healthy lifestyles to children and their families.

Design: Written questionnaires were sent to 1100 Victorian OSHC programs to collect information about the services, foods and activities offered to children, the training and resources utilised by staff and the type of information sent home to parents/guardians.

Subjects: A total of 426 Victorian OSHC coordinators completed questionnaires in the present descriptive study (39% response rate).

Setting: Out of school hours care provides care for 5–12 years olds before school, after school and/or during school holidays.

Results: Over 80% of coordinators reported offering fruit, breads, cereals, and milk and dairy products. One-third offer vegetables as part of meals or snacks. One-third reported offering cakes, biscuits and/or slices, and chips and/or pastries. About 17% reported offering water, whereas 24% reported offering cordial/soft drinks and fruit juice. Cooking was offered as an after-school activity by about half of those surveyed. Active games were common (62%) as were indoor active games and sports (36%). Sedentary activities were also commonplace (37–51%). Only about 30% of OSHC coordinators had participated in nutrition and/or physical activity training in the previous two years. Few OSHC programs sent home health information to parents/guardians.

Conclusion and application: Opportunities exist to help Victorian OSHC programs with nutrition and physical activity information, resources and training. Although the findings of the present study are specific to Victoria, they highlight the potential role of the growing OSHC sector to help improve the health of Australian children.

Terrestrial detritus supports the food webs in lowland intermittent streams of south-eastern Australia : a stable isotope study

1. Large amounts of terrestrial detritus enter many low-order forested streams, and this organic
material is often the major basal resource in the metazoan food webs of such systems. However,
despite their apparently low biomass, algae are the dominant food of organisms in a number of
aquatic communities which conventionally would have been presumed to be dependent on
allochthonous detritus, particularly those in the tropics and also in lowland intermittent streams
in arid Australia.
2. The dual stable isotope signatures (d13C and d15N) of potential primary food sources were
compared with the isotopic signatures of common aquatic animals in lowland intermittent
streams in south-eastern Australia, in both spring and summer, to determine whether
allochthonous detritus was an important nutritional resource in these systems. The isotopic
signatures of the major potential allochthonous plant food sources (Eucalyptus, Phalaris and
Juncus) overlapped, but were distinct from algae and the dominant macrophytes growing in the
study reaches. The isotopic signatures of biofilm were more spatially and temporally variable
than those of the other basal resources.
3. Despite allochthonous detritus having relatively high C : N ratios compared to other
potential basal resources, results from ISOSOURCE mixing model calculations demonstrated
that this detritus, and the associated biofilm, were the major energy sources assimilated by
macroinvertebrate primary consumers in both spring and summer. The importance of these
energy sources was also reflected in animals higher in the food web, including predatory
macroinvertebrates and fish. These resources were supplemented by autochthonous sources of
higher nutritional value (i.e. filamentous algae and macrophytes, which had relatively low
C : N ratios) when they became more prolific as the streams dried to disconnected pools in
summer.
4. The results highlight the importance of allochthonous detritus (particularly from Eucalyptus)
as a dependable energy source for benthic macroinvertebrates and fish in lowland intermittent
streams of south-eastern Australia. This contrasts with previous stable isotope studies
conducted in lowland intermittent streams in arid Australia, which have reported that the fauna
are primarily dependent on autochthonous algae.

Diet of an eastern barn owl Tyto javanica on the Patho Plains, northern Victoria

A small sample of eastern Barn Owl Tyto javanica pellets, from native grasslands on the Patho Plains in northern Victoria in February 2007, contained the remains of 48 prey individuals: 38 Australian Plague Locusts Chortoicetes terminifera, nine house Mice Mus domesticus and one Fat-tailed dunnart Sminthopsis crassicaudata. Such a high proportion of locusts in the eastern Barn Owl's diet is noteworthy, and is discussed in the context of recent locust-spraying operations in the region.

Ecology of epifaunal caridean shrimps in the Hopkins River estuary, and the role of estuaries in the life history of the atyid "Paratya Australiensis" Kemp, 1917 in south-eastern Australia

This study examined the factors affecting the distribution and abundance of epifaunal caridean shrimps in seagrass meadows of the Hopkins River estuary in south-western Victoria, Australia, and investigated the life history patterns of the freshwater Parana australiensis, found for the first time in estuaries. Adult and sub-adult shrimps were surveyed in seagrass meadows along the estuary over two years, and their planktonic larvae were surveyed in adjacent waters. Three species were collected. The marine Palaemon serenus occurred only near the mouth, summer to autumn, in high salinities. The marine/estuarine Macrobrachium intermedium occurred throughout the estuary. Adults were most abundant in late autumn, and least abundant in summer (unlike trends reported in marine meadows). Densities were higher and less variable in downstream meadows. P. australiensis occurred in the upper estuary all year, most abundantly in spring, due to migration from the river after peak discharge. Ovigerous females dominated, while males, showing less migration into the estuary, dominated above estuarine influence. Adults disappeared from the estuary in summer as salinity rose. Breeding period for P. australiensis was briefer in the estuary (September-December) than upstream (July-April). M. intermedium began breeding later in the upper estuary (November/December-March) than in the lower estuary (October-March), probably reflecting a physiological response to lower salinity, rather than an interaction with P. australiensis. No ovigerous P. serenus were found in the estuary. Larvae of P. australiensis and M intermedium occurred abundantly throughout the estuary, but P. serenus larvae did not. P. australiensis was an early coloniser to the plankton after peak discharge (November-December). Larvae concentrated in the deep saline layer at the head of the intruding salt wedge, thus probably maintaining longitudinal position. Diurnal vertical migrations were evident within the salt wedge, and in a deep pool above tidal influence. M. intermedium larvae occurred October-May in the lower estuary and November-April in the upper estuary, peaking in abundance one to two months after P. australiensis. They were associated with low surface flows and surface salinities greater than 10, over an anoxic deeper layer. All three species exhibited extended development of euryhaline larvae in the laboratory. Tolerances and optimal salinities of larvae of the three species reflected their distributions. M. intermedium was the most euryhaline species. P. australiensis larvae were tolerant of higher salinities than juveniles of adults: capable of developing in salinity of at least 15. Most P. australiensis juveniles recruited to the estuary November-December, after which numbers declined dramatically. After settlement, most recruits probably migrated upstream out of the estuary. Two cohorts of M. intermedium recruited to the estuary from larvae in summer (December and February), but some juveniles also migrated from adjacent coastal waters. Post-larval migration was at least as important a determinant of abundance as direct recruitment from estuarine, planktonic larvae in all three species. Distributions among seagrass meadows along the estuary were determined primarily by physico-chemical patterns driven by hydrological changes. Seasonal variations in salinity and temperature were strongly associated with seasonal variations in shrimp abundance. Salinity tolerances of adults of the three species reflected their distribution patterns. Biotic interactions were more important in determining distributions within meadows. P. australiensis, when abundant, were associated with seagrass biomass. M. intermedium were also, but when seagrass was sparsest and least extensive. The two species apparently partitioned the seagrass meadow according to depth in early summer. Laboratory experiments suggested P. australiensis was displaced from deeper water by M. intermedium. Preference for vegetative complexity and competition for position within meadows suggest the underlying importance of predation in regulating shrimp populations. A survey of south-eastern Australian estuaries found P. australiensis larvae abundant in all stable, open, well-developed, salt-wedge estuaries where adults were abundant. Adults were most abundant in low salinities among submerged leafy macrophytes. Reproductive traits of P. australiensis were compared in estuarine and fresh reaches of three rivers. Early in the breeding season, egg size was smaller, and (size-specific) egg number larger in estuaries than upstream. A trade-off between egg size and egg number resulted in no difference in total (size-specific) reproductive investment between locations. Reproductive investment tended to decrease at some locations over the breeding season, and this decrease was a result of decreased egg size in most cases. The decrease in reproductive investment probably reflected reduced food availability for the adult, while the reduced egg size was probably a response to improved conditions for larval development. In the Hopkins River, larger egg size at upstream sites was reflected in larger early stage larvae. Later stage larvae were larger in the estuary, suggesting more favourable conditions for larval development. Allozyme electrophoresis showed the P. australiensis populations in each of the three rivers to be distinct. Allozyme frequencies were not different within the Hopkins River, but upstream and estuarine locations in the Curdies and Gellibrand were different. Although some variation in reproductive traits within catchments may have been due to genotypic differences, trade-offs between egg size and number, and decreases in egg size over summer were probably due to plastic responses to environmental cues. It is proposed P. australiensis inhabits and reproduces in both estuarine and freshwater environments by plastic response to environmental conditions. Recruitment to estuaries is dependent on the presence of suitable adult, littoral habitat, and a stable salt wedge for larval retention. Estuaries are important recruitment sites for P. australiensis, potentially allowing an extra brood each year before riverine recruitment. Estuarine broods could constitute a large part of the total fecundity of P. australiensis females. Euryhaline larvae and estuarine recruitment of P. australiensis suggest marine transport of larvae between estuaries as a possible dispersal mechanism for Paratya species.

Other communities : Box mistletoe (Amyema miquelii) parasitism is not detrimental to the health of grey box (Eucalyptus microcarpa) trees at a regional scale

Mistletoes are hemiparasites that occur worldwide in many types of forest, woodland and shrubland ecosystems (Watson 2001). Some species are regarded as pests due to their detrimental effects on host species (Hawksworth 1983; Reid & Yan 2000). Heavy infestations can affect the growth, productivity and form of host trees, and may cause host death (Reid et al. 1994; Shaw et al.2004, 2008). In south-eastern Australia, mistletoes often are visibly obvious in trees along roadsides, in paddocks and on the margins of open forests; and concerns have been expressed about their potentially detrimental effects on host trees.Despite this, little quantitative information is available on the effects of mistletoes on tree health and mortality (Reid et al. 1994). Are detrimental effects widespread or localized? A first step is to assess whether trees parasitized by mistletoe are less healthy than those without such parasites. Here, we investigate the relationship between parasitism by Box Mistletoe (Amyema miquelii (Lehm. ex Miq.) Tiegh.), a common species in south-eastern Australia, and the health of trees of a widespread host species, Grey Box (Eucalyptus microcarpa (Maiden) Maiden), across a large geographic region.

Integrating agriculture and food policy to achieve sustainable peri-urban fruit and vegetable production in Victoria, Australia

Efforts to increase fruit and vegetable consump­tion are a significant aspect of national approaches to preventive health. However, policy frameworks for increasing fruit and vegetable consumption rarely take an integrated food-systems approach that includes a focus on production. In this policy analysis and commentary we examine fruit and vegetable production in peri-urban areas of Melbourne in Victoria, Australia, and highlight the significance of emerging environmental and eco­nomic pressures on fruit and vegetable production. This examination will be of interest to other locations around the world also experiencing pressure on their peri-urban agriculture. These pressures suggest that the availability and afforda­bility of fruit and vegetable supplies cannot be taken for granted, and that future initiatives to increase fruit and vegetable consumption should include a focus on sustainable production. Threats to production that include environmental pressures, together with the loss and cost of peri-urban agri­cultural land and a cost-price squeeze due to rising input costs and low farm-gate prices, act in combi­nation to threaten the viability of the Victorian fruit and vegetable industries. We pro­pose that policy initiatives to increase fruit and vegetable consumption should include measures to address the pressures facing production, and that the most effective policy responses are likely to be integrated approaches that aim to increase fruit and vegetable availability and affordability through innovative solutions to problems of production and distribu­tion. Some brief examples of potential integrated policy solutions are identified to illu­strate the possibilities and stimulate discussion.

Reduced food access due to a lack of money, inability to lift and lack of access to a car for food shopping : a multilevel study in Melbourne, Victoria

Objective: To describe associations between demographic and individual and arealevel socio-economic variables and restricted household food access due to lack of money, inability to lift groceries and lack of access to a car to do food shopping.
Design: Multilevel study of three measures of restricted food access, i.e. running out of money to buy food, inability to lift groceries and lack of access to a car for food shopping. Multilevel logistic regression was conducted to examine the risk of each of these outcomes according to demographic and socio-economic variables.
Setting: Random selection of households from fifty small areas in Melbourne, Australia, in 2003.
Subjects: The main food shoppers in each household (n 2564).
Results: A lack of money was significantly more likely among the young and in households with single adults. Difficultly lifting was more likely among the elderly and those born overseas. The youngest and highest age groups both reported reduced car access, as did those born overseas and single-adult households. All three factors were most likely among those with a lower individual or household socio-economic position. Increased levels of area disadvantage were independently associated with difficultly lifting and reduced car access.
Conclusions: In Melbourne, households with lower individual socio-economic position and area disadvantage have restricted access to food because of a lack of money and/or having physical limitations due difficulty lifting or lack of access to a car for food shopping. Further research is required to explore the relationship between physical restrictions and food access.

Food policy development in the Australian state of Victoria : a case study of the Food Alliance

This article explores the development of a food policy body called the Food Alliance and the role of the organization in encouraging the development of food policy that integrates health and ecological issues. The Food Alliance is located within the Australian state of Victoria. A policy triangle is used as a framework to describe and analyse the work of the Food Alliance. Lessons are drawn about effective strategies for influencing integrated food policy. This occurs in a context where food policy typically favours powerful industry and agricultural interests and where relationships between the health and environmental sectors are in their infancy. The implications for planning and organizing a state-wide food policy are explored from the perspective of policy and the ways in which this can be influenced through working with key stakeholders.

Sociodemographic factors associated with healthy eating and food security in socio-economically disadvantaged groups in the UK and Victoria, Australia

Objective
To investigate the associations between sociodemographic factors and both diet indicators and food security among socio-economically disadvantaged populations in two different (national) contextual settings.

Design
Logistic regression was used to determine cross-sectional associations between nationality, marital status, presence of children in the household, education, employment status and household income (four low income categories) with daily fruit and vegetable consumption, low-fat milk consumption and food security.

Setting
Socio-economically disadvantaged neighbourhoods in the UK and Australia.

Subjects
Two samples of low-income women from disadvantaged neighbourhoods: (i) in the UK, the 2003–05 Low Income Diet and Nutrition Survey (LIDNS; n 643); and (ii) in Australia, the 2007–08 Resilience for Eating and Activity Despite Inequality (READI; n 1340).

Results
The influence of nationality, marital status and children in the household on the dietary outcomes varied between the two nations. Obtaining greater education qualifications was the most telling factor associated with healthier dietary behaviours. Being employed was positively associated with low-fat milk consumption in both nations and with fruit consumption in the UK, while income was not associated with dietary behaviours in either nation. In Australia, the likelihood of being food secure was higher among those who were born outside Australia, married, employed or had a greater income, while higher income was the only significant factor in the UK.

Conclusions
The identification of factors that differently influence dietary behaviours and food security in socio-economically disadvantaged populations in the UK and Australia suggests continued efforts need to be made to ensure that interventions and policy responses are informed by the best available local evidence.