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Abstract: Fruit has been identified as an important and potentially population-restricting food for southern red-backed voles (Myodes gapperi (Vigors, 1830)), deer mice (Peromyscus maniculatus (Wagner, 1845)), and woodland jumping mice [...]

Leaf herbivores potentially reduce plant fitness by increasing fruit abortion. The impact of leaf herbivory on fruit abortion, however, may vary with branch height in trees because of differential investment in reproduction among branches, differences among branches in exposure to solar radiation and the mobility, of resource movement among branches following defoliation. Here we describe spatial patterns in abundance of lepidopteran herbivores and resultant damage in the canopy of mature white oak trees, Quercus alba. The effect of foliar damage on fruit abortion for upper and lower canopy branches was also examined. A significant positive correlation occurred between foliar damage and spring herbivore abundance. Damage measured at the end of the season was unevenly distributed throughout the canopy, varying from 10-20% leaf area loss. A significant positive correlation between percent herbivore damage and percent fruit abortion also existed. Moreover, upper canopy branches had a higher percentage of fruit abortion for a given damage level than lower canopy branches, even though herbivore damage did not differ significantly with canopy height. These results suggest that early season leaf-chewing herbivores negatively affected fruit production, but the impact on fruit abortion depended upon the location of the damaged branch. Resources apparently did not move from lesser-damaged branches to more heavily damaged branches to reduce reproductive losses.

In this paper we analyze the seed dispersal stage of the Prunus mahaleb - frugivorous bird interaction from fruit removal through seed delivery within the context of disperser effectiveness. The effectiveness of a frugivorous species as a seed disperser is the contribution it makes to plant fitness. Effectiveness depends on the quantity of seed dispersed ('quantity component') and the quality of dispersal provided each seed ('quality component'). For the main frugivores, we studied abundance, visitation rate, and feeding behavior, the major variables influencing the quantity component of effectiveness, and the postforaging microhabitat use and resultant seed shadows, which set the stage for postdispersal factors that will influence the quality component of effectiveness. Legitimate seed dispersers (SD) swallowed fruits whole and defecated or regurgitated intact seeds; pulp consumers (PC) pecked fruits to obtain pulp and dropped seeds to the ground, but some species occasionally dispersed seeds (PCSD species). Overall numbers of fruits removed (i.e., handled) by avian frugivores were similar in the two study years; however, the estimated percentage of seeds dispersed differed significantly, with lower relative dispersal success in the year with greater relative abundance of PC species. Similar numbers of seeds were dispersed in the two years despite nearly a fourfold difference in number of fruits produced. Fruit crop size explained >80% variance in the number of seeds dispersed per tree. A total of 38 species of birds were recorded during censuses, with frugivores representing 68.8% of them; the relative representation of SD, PC, and PCSD species was 42.2%, 17.2%, and 9.4%, respectively. Individual trees showed extensive variation in visitation rates, ranging from 0.3 to 41.6 visits/10 h in any year. The main visitors were the SD species Phoenicurus ochruros (10.8 visits/10 h), Turdus viscivorus (9.2 visits/10 h), Erithacus rubecula (3.5 visits/10 h), and Sylvia communis (2.6 visits/10 h); and the PC species Fringilla coelebs (16.7 visits/10 h) and Parus ater (4.7 visits/10 h). Species with large quantity components of effectiveness typically had either high visit or high feeding rates, combined with high probability of dispersing a handled seed. Variation among species in fruit-handling behavior, however, was the main factor influencing variation in the quantity component. Visit rate in turn was influenced largely by local abundance. No single frugivore trait, however, can adequately estimate the quantity component of disperser effectiveness. A 'gulper'/'masher' dichotomy helps explain differences in fruit handling among major frugivore types and shows many correlates with other aspects of frugivore activity that ultimately influence the quantity component. Most species showed marked preferences for microhabitats with plant cover, especially P. mahaleb, midheight shrubs, and Pinus (86.1% of the departure flights) and avoided open microhabitats. Most flights were over short distances (77.5% to perches located within 30 m). Among the main frugivores, 40.3% of the exit flights were to perches > 15 m away from the feeding tree, but only 18.5% of these flights were to perches > 15 m from any P. mahaleb. Covered microhabitats received significantly more seeds (39.3 +/- 5.0 seeds dispersed/m(super 2), 1988 [mean +/- 1 SE]; 31.7 +/- 5.9 seeds dispersed/m(super 2), 1989) than open microhabitats (2.8 +/- 0.7 seeds dispersed/m(super 2), 1988; 1.8 +/- 0.4 seeds dispersed/m(super 2), 1989). The potential contribution of each bird species to the seed rain in each microhabitat was estimated from the number of visits recorded, the mean number of seeds, dispersed per visit, and the proportion of exit flights to each microhabitat. Microhabitats differed strongly in the proportions of seeds delivered by the main frugivores, and bird species also differed in the proportions of seeds delivered to a given microhabitat. The seed rain to covered microhabitats was delivered by a more heterogeneous assortment of species than the seed rain to open sites. The resulting seed shadow was a complex result of the interaction between movement patterns of a suite of bird species differing both in the quantity of seed dispersed and microhabitat preferences and in the landscape distribution of these microhabitat patches. This seed shadow was extremely nonrandom due both to a strong overall preference by most of the birds for the relatively scarce covered microhabitats and to species-specific preferences for particular types of covered microhabitats. Different microhabitat types not only received variable amounts of dispersed seed, but also differed in the number and identity of disperser species contributing to that seed rain. Keywords: avian frugivory; fruit removal; fruit size; Mediterranean scrubland; mutualism; plant demography; seed dispersal; seed rain; Spain; Sylvia; Turdus.

Most deciduous fruit trees need sufficient accumulated chilling, or vernalisation, to break winter dormancy. Inadequate chilling due to enhanced greenhouse warming may result in prolonged dormancy, leading to reduced fruit quality and yield. The potential impact of warming on chill accumulation has been analysed using the Utah vernalisation model and temperature data from over 400 climate stations in southern Australia. Two experiments were performed: (i) a sensitivity study where temperatures were increased at all sites by either 1, 2 or 3 [degrees] C; (ii) a scenario study for the year 2030 where temperatures were increased according to spatially- and seasonally-varying warming scenarios derived from five global climate models under enhanced greenhouse conditions. The sensitivity study shows that warming causes greater reduction in chilling at sites with a higher present mean temperature and/or a wider diurnal temperature range. In the scenario study, two warming scenarios for the year 2030 were considered: a low (high) warming scenario which assumes a low (high) rate of increase of greenhouse gas emission, a low (high) global climate sensitivity to increased emissions, and a low (high) regional temperature response. The low warming scenario is less than 1 [degree] C in southern Australia and is unlikely to affect the vernalisation of high-chill fruit, except for pome-fruit grown in south-west Western Australia. The high warming scenario exceeds 1.5 [degrees] C and would significantly increase the risk of prolonged dormancy for both stone-fruit and pome-fruit at many sites.

The behavioral responses of a group of white-faced sakis' (Pithecia pithecia) to fruit and water scarcity are described. In response to the scarcity of fruit, the sakis ate more young leaves, insects and flowers and mean distances between feeding bouts fell significantly and the sakis revisited tress less often.

I investigated the effects of display size and flowering phenology on fruit set in Aucuba japonica, an understory dioecious shrub pollinated by opportunistic insects. Natural variations in display size, flowering phenology, and fruit set were monitored in 1997. A hand-pollination experiment was also conducted to check whether pollen limitation was a factor in fruit set in the field. Increases in floral display size did not affect fruit set; the proportion of flowers that set fruit was almost constant irrespective of the total number of flowers per inflorescence, the total number of inflorescences per plant, and the total number of flowers per plant. The hand-pollination experiment showed that fruit set was not pollen limited despite the low mating probability that resulted from the combination of dioecism and the species' dependence on opportunistic pollinators. This was due, in part, to the fact that female flowers did not have a predetermined period of receptivity, but instead remained receptive until they received pollen. In contrast, flowering phenology did affect fruit set. Fruit set was most abundant when male and female flowering was most abundant. This suggests there was some degree of pollen limitation during the part of the flowering season when male flowers were scarce. Key words: Aucuba japonica; Cornaceae; dioecy; flowering phenology; fruit set, resource limitation.

HANNAH B. SUTHERS, [1,4] JEAN M. BICKAL, [2] PAUL G. RODEWALD [3] ABSTRACT.--We evaluated the effects of plant succession on habitat use and fruit resource availability migratory and resident songbirds [...]

Attractive supermarket displays of tropical fruit conceal ugly environmental and social costs CANADIANS TAKE IT for granted that they can walk into the nearest supermarket in the middle of winter […]

Background. Restaurants are among the most important and promising venues for environmental, policy, and pricing initiatives to increase fruit and vegetable (F&V) intake. This article reviews restaurant-based environmental, policy and pricing strategies for increasing intake of fruits and vegetables and identifies promising strategies, research needs, and innovative opportunities for the future. Methods. The strategies, examples, and research reported here were identified through an extensive search of published journal articles, government documents, the internet, and inquiries to leaders in the field. Recommendations were expanded based on discussion by participants in the CDC/ACS-sponsored Fruit and Vegetable, Environment Policy and Pricing Workshop held in September of 2002. Results. Six separate types of restaurant-based interventions were identified: increased availability, increased access, reduced prices and coupons, catering policies, point-of-purchase (POP) information, and promotion and communication. Combination approaches have also been implemented. Evaluation data on these interventions show some significant impact on healthful diets, particularly with point-of-purchase information. However, most published reports emphasize low-fat eating, and there is a need to translate and evaluate interventions focused on increasing fruit and vegetable intake. Conclusions. Several models for changing environments, policy and pricing to increase fruit and vegetable availability, access, attractiveness and consumption in restaurants have been tested and found to have some promise. There is a need to evaluate fruit and vegetable-specific strategies; to obtain data from industry; to disseminate promising programs; and to enhance public-private partnerships and collaboration to expand on current knowledge.

Chimpanzees (Pan troglodytes verus) at the Fongoli study site in southeastern Senegal were hypothesized to compete over the fruit, Saba senegalensis, with humans of the Bedik, Bassari, Malenke, and Diahanke groups based on preliminary observations of extensive gathering of Saba by local people in May-June 2001. Chimpanzees fed on both unripe and ripe Saba fruit from February-July and focused on this food resource during the driest, hottest months (May-June). Saba seeds were found in most (>69%) chimpanzee feces collected from April 2001-July 2002, with an average of 41 seeds found per sample throughout the study period (N=117). Chimpanzees may therefore be effective dispersal agents for this plant species. Given that S. senegalensis seems to be a keystone food source for chimpanzees here, an assessment of the role that the fruit played in the local economy of people in the area and how this might affect both the S. senegalensis and chimpanzee populations at Fongoli was conducted from May-August 2002. A key informant approach was used to determine the most significant participants in harvesting and marketing Saba. Women and children have recently begun to harvest wild Saba from surrounding woodlands for export to markets in larger cities such as Dakar and Bamako, Mali. The goal of this research is to bettor understand the dynamics among the human, chimpanzee, and Saba senegalensis populations in southeastern Senegal and to design a plan for the sustainable harvest of a fruit species that is important to both humans and chimpanzees in the area.