Diurnal foraging‐mode shifts and food availability in nectarivore assemblages during winter

Abstract Temporal fluctuations of food resources and foraging activities have been studied extensively, especially at longer timescales (monthly, seasonally, among years). However, short‐term variation (e.g. within days) is less well understood. Here we systematically quantified diurnal patterns of foraging by nectarivorous birds (meliphagid honeyeaters) that numerically dominated stands of a winter‐flowering eucalypt, the red ironbark, Eucalyptus tricarpa, in central Victoria, Australia. Diurnal variation in food resources also was measured. Data were collected in winter. Anecdotal observations that honeyeaters change from almost exclusive nectarivory early in the day to a higher fraction of insectivory – especially aerial hawking – later in the day were confirmed, although in areas of high flowering intensity, nectar‐feeding remained the dominant foraging activity throughout the day. Local climatic factors (ambient temperature, windiness and cloud cover) all varied systematically through the day. Together, results were consistent with a change in foraging emphasis to greater insectivory as a function of elevated activities of insects (especially aerial ones), which was probably fostered by higher ambient temperatures. Contrary to energetic expectations, the nectarivores were very active early in the morning when ambient temperatures averaged approximately 3°C, well below thermoneutral temperatures. We deduced that the potential benefits of gathering as much energy‐rich nectar as possible before it was depleted outweighed the high costs of activities at low temperatures.     

An Iridovirus from the black beetle,Heteronychus arator (Coleoptera : Scarabaeidae)

Abstract

Iridescent virus type 23 from the black beetle (Heteronychus arator) replicated in Spodoptera frugiperda cells, producing some cell vacuolation after 3 days and extensive vacuolation and detachment of cells 7 days after infection. The virus also replicated in Aedes albopictus cells, and in the larvae and pupae of Galleria mellonella.     

Symposium introduction: The importance of scale in ecology

Abstract Conceptual issues about scale, both spatial and temporal, have had considerable influence on the way in which ecologists view populations, communities and ecosystems. Scale includes two aspects: the extent over which a community or ecosystem is studied, and the resolution or ‘grain’ at which measurements or experiments are conducted. We illustrate the influence of extent and grain on perceptions of ecological patterns and processes, derived from fundamental measurements, field experiments and theory and modelling. These concepts provide background for a series of subsequent papers that were presented at a symposium on spatial and temporal scaling in freshwater systems. These papers conclude that multi-scale measurements and experiments plus novel methodologies for analysing large-scale surveys and manipulations should be priorities for future research in freshwater systems.     

The foraging of New Zealand honeyeaters

Abstract

New Zealand has three species of honeyeaters, all of which feed on nectar, fruit, and ‘insects’. There is disagreement between published data and those becoming available from long-term studies on the relative proportion of these items in the diet. The effect of factors such as body size, dominance status, degree of movement, and time of year on diet and foraging behaviour are outlined, and predictions of differences between species and between sexes are made. A brief comparison of foraging in relation to the flora is made between New Zealand and Australian species.     

An introductory ecological biogeography of the Australo-Pacific Meliphagidae

Abstract

The Meliphagidae, that can readily be defined on tongue characteristics, are a monophyletic group centred in the Australo-Pacific region, but with one African genus (Promerops). The classification of Salomonsen (1967) allows 38 genera and 170 species in the former region, and one genus with two species in the latter. Australia and New Guinea jointly have 23 genera and 108 species, and constitute the centre of diversity of the group. Endemic genera are concentrated in Australia and New Guinea, and around the periphery of the Pacific part of the range (Sulawesi, Bonins, Marianas, Hawaii, New Zealand). The meliphagids are diversified in body size and bill form. They are basically nectarivores and insectivores, with most species combining the two roles to varying degrees. There is a good general correlation between bill form and way of life. A few species feed on trunks and aerial flycatching is well developed in many. Morphological modification is only minor in these instances and the meliphagids as a group remain rather generalised in bodily proportions. A long period of coevolution with Australian plant elements is shown by meliphagids being the major pollinators of several tree and shrub genera.

The group combines monotypic genera with restricted ranges and wide-ranging genera with many species. Of the latter; Myzomela, Lichema, and Philemon are centred in the tropics, and Meliphaga and Phylidonyris in Australia. Most of these co-occur over a wide area, this being favoured by differences in body size and bill morphology.

Comparison of three kinds of meliphagid communities, two typical continental ones, two of isolated forest outlyers in Australia, and six insular Pacific ones, shows the first to be rich (10 and 11 genera, 21 and 17 species), and the second impoverished (6 and 7 genera, 9 and 12 species). Individual Pacific island groups, however, have only 2–5 genera, and 3–6 species. Genus to species ratios are 0.55–0.64 in the major continental communities, but are 1.0 in New Zealand and Samoa.

Morphological distance between species, measured as the percent difference in size between successive members along a size gradient is 5.4 and 5.5% for wing length and 4.9 and 9.3% for bill length in the two continental communities. It increases to 7.8–14.9, and 11.3–12.7%, respectively, in the isolated forest outlyers of Tasmania and southwestern Australia. The figures are 23.0 and 35.0% for wing and bill length in New Zealand, and 41.0 and 51.0% in Fijian forms. This accords with current theory that in impoverished insular environments, size separation of co-occurring species must be greater.

The marked success of the Meliphagidae in the Australo-Pacific region can be attributed to their versatility and adaptibility, and dual role of insectivore and nectarivore in an area exceptionally rich in nectar-producing trees and shrubs.     

Regent Honeyeater Habitat Restoration Project Lurg Hills, Victoria

Summary  The Regent Honeyeater Habitat Restoration Project is a landscape scale community effort to protect and restore all significant remnants of native woodland habitat in the agricultural district of the Lurg hills, Victoria. While focus is placed on the Regent Honeyeater, many other declining birds and mammals also benefit from the restoration project. Over 14 years of sustained effort, the project has involved 115 local landholders (approximately 95% of local farms) and about 17 000 volunteers. Together, they have protected relatively healthy remnants by fencing, planted or direct seeded depleted understoreys and replanted open areas that had been cleared for agriculture. Other restoration activities include ecological thinning of 'pole forests', mistletoe removal, environmental weeding, feral animal control, kangaroo reduction, systematic monitoring of a range of threatened and declining woodland birds, and nest box placement for hollow-dependent mammals. The works have achieved the rapid closing of some high-priority gaps in the local landscape, connecting the Lurg hills project area to other major regional habitats nearby. The oldest tree plantings are now 12 yrs old and 6-m high and the first Ironbarks flowered in 2006. While the Regent Honeyeater has not yet returned in numbers (because the trees have not yet reached optimum flowering age), surveys and nest box monitoring reveal a range of threatened birds and mammals are already using this project's regenerated and reconstructed habitats.     

Levels of understanding in ecology: interspecific competition and community ecology

Abstract Ecological interpretation has been subject to several divisive controversies, involving, for example, the significance of density dependence and interspecific competition as ecological processes. Generally, resolution has been obtained through compromise and concensus or calls for yet more data. Essentially, both sides in the discussion are seen to have been correct to some extent. As a consequence the debates have been portrayed widely as having been sterile. We agree, but only because they have been conducted at a level so superficial that the relevance of the original criticisms to the theoretical structure of ecology has not been widely appreciated, nor resolved. Debate that deals with ecological generalizations must be conducted at a level appropriate to such aims.     

An introduction to primate behavioral ecology suitable for college students?

Review of Primate Behavioral Ecology by Karen B. Strier. Boston, Allyn and Bacon, 2000, viii + 392 pp, 216 fig., 15 tab., $37.00.     

Wing noises,wing slots,and aggression in New Zealand honeyeaters (Aves: Meliphagidae)

Abstract

Two of New Zealand’s honeyeaters, the tui (Prosthemadera novaeseelandiae) and the bellbird (Anthornis melanura) can produce loud wing noises. In both species, modified primary feathers form slots in the wing that presumably make these noises. The slots of bellbirds are similar to those of hummingbirds (Trochilidae). Asymmetries in aggressiveness — as determined from inter- and intraspecific dominance — are closely related to the presence or size of the wing slots.     

Human behavioral ecology: I

New fields of inquiry rarely spring fully grown from the forehead of a single genius, and in addition, it is often difficult to decide when a related set of inquiries has coalesced sufficiently to define a field. As measured by the solicitation and publication of review articles, human behavioral ecology has recently become a self-conscious field, for this is the third essay to review it^1,2 and a book-length survey will appear later this year.³ In this two-part article, I will try to give readers a sense of the field by outlining its theoretical and methodological principles and key issues and by summarizing representative studies and unresolved questions in three main topical areas: subsistence strategies (Part I) and reproductive strategies and social interactions (Part II).     

国际化学生态学文献、实验室网络资源评介

本文介绍了国际上化学生态学的文献和网络资源 ,包括重要著作简介、杂志的特点和网址、实验室的工作内容和网址 ,一些网络讨论组 ,以及主要的组织机构和会议等。     

Human behavioral ecology: II

Human behavioral ecology is an interdisciplinary field of study applying theory from evolutionary ecology to a variety of anthropological questions. In Part I of this essay,¹ which appeared in an earlier issue, I surveyed key theoretical and methodological elements of the field, and summarized representative studies and issues in the topical area of subsistence strategies. In Part II, I turn to studies of reproductive strategies, and those analyzing patterns of cooperation and competition in an ecological and adaptive framework. I conclude with a brief look at possible future developments in the field.     

From introduction to equilibrium: reconstructing the invasive pathways of the Argentine ant in a Mediterranean region

Determining the geographical range of invasive species is an important component of formulating effective management strategies. In the absence of detailed distributional data, species distribution models can provide estimates of an invasion range and increase our understanding of the ecological processes acting at various spatial scales. We used two complementary approaches to evaluate the influence of historical and environmental factors in shaping the distribution of the Argentine ant ( Linepithema humile ), a widespread, highly invasive species native to South America. Occurrence data were combined with environmental data at incremental spatial scales (extent and resolution) to predict the suitable range of the ant invasion using ecological niche models. In addition, we also used a spread model that simulated the jump dispersal of the species to identify the most plausible scenarios of arrival of L. humile in the NE Iberian Peninsula at local scales. Based on the results of both modelling practices, we suggest that L. humile might have reached its maximum geographic range at regional scales in the NE Iberian Peninsula. However, the species does not appear in equilibrium with the environment at small spatial scales, and further expansions are expected along coastal and inland localities of the Costa Brava. Long-distance jumps are ultimately responsible for the spread of the Argentine ant in the area. Overall, our study shows the utility of combining niche based models with spread models to understand the dynamics of species' invasions.     

Predictive ecology: systems approaches

The world is experiencing significant, largely anthropogenically induced, environmental change. This will impact on the biological world and we need to be able to forecast its effects. In order to produce such forecasts, ecology needs to become more predictive--to develop the ability to understand how ecological systems will behave in future, changed, conditions. Further development of process-based models is required to allow such predictions to be made. Critical to the development of such models will be achieving a balance between the brute-force approach that naively attempts to include everything, and over simplification that throws out important heterogeneities at various levels. Central to this will be the recognition that individuals are the elementary particles of all ecological systems. As such it will be necessary to understand the effect of evolution on ecological systems, particularly when exposed to environmental change. However, insights from evolutionary biology will help the development of models even when data may be sparse. Process-based models are more common, and are used for forecasting, in other disciplines, e.g. climatology and molecular systems biology. Tools and techniques developed in these endeavours can be appropriated into ecological modelling, but it will also be necessary to develop the science of ecoinformatics along with approaches specific to ecological problems. The impetus for this effort should come from the demand coming from society to understand the effects of environmental change on the world and what might be performed to mitigate or adapt to them.