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Fear of humans and its effect on animal behavior is increasingly being recognized as an important structuring force in ecological landscapes, with consequences for ecological interactions and communities. When aggressive, physically dominant species are displaced by anthropogenic disturbance, physically weaker species exploit competitor and predator downtimes to forage in previously risky places. Birds feeding at outdoor restaurants and cafés in association with humans are exposed to fluctuating levels of perceived danger caused by frequently changing densities of human diners. Consequently, birds must make decisions about which dining tables to visit based on trade-offs between foraging gain and perceived danger from avian competitors and humans. We tested the hypothesis that interspecific differences in response to perceived danger, combined with varying densities of human diners, dynamically alter which bird species predominates at dining tables. We found that house sparrows (Passer domesticus) tolerated higher human diner-densities than larger-sized, more physically dominant Eurasian jackdaws (Coloeus monedula). Sparrows were usually the first birds to visit diner-occupied tables and spent more time there than jackdaws. However, at diner-abandoned tables, this pattern changed: During low diner-densities at surrounding tables, jackdaws were usually the predominant species in first visits and minutes spent visiting, while at high diner-densities sparrows usually predominated. Moreover, along a gradient of increasing human diner-density, sparrows gradually replaced jackdaws as the predominant species in first visits and time at abandoned tables. However, at diner-occupied tables, once a sparrow chose which table to visit, factors other than diner-density influenced its choice of where to forage there (table-top or ground). To our knowledge, our research is the first scientific study of table-visiting behavior by birds at outdoor restaurants and cafés, and the first

Background: Birds frequently visit the outdoor serving areas of restaurants to feed on scraps of food and leftovers. Although this feeding association between humans and birds is widespread and could have significant effects, both positive and negative, for all taxa involved, the authors know of no published studies that have investigated restaurant bird communities. To lay the foundation for future research, the authors conducted a basic study of birds at 80 outdoor restaurants in Sweden, identifying which species and taxonomic clades of birds visited the restaurants and comparing restaurant birds in urban and rural environments. New information: Thirteen species of birds visited the outdoor restaurants. Eight of these species were predominant, i.e. accounting for 51% or more of bird presence (sum of minutes of all individual birds) at one or more restaurants. Every restaurant studied had a predominant species, but species often differed from each other in frequency of predominance in different landscapes. No endangered species were seen visiting restaurants. However, three farmland bird species (House Sparrow Passer domesticus, White Wagtail Motacilla alba, Eurasian Tree Sparrow Passer montanus), whose numbers are reported to be declining in the countryside, were predominant at the majority of restaurants in rural areas, suggesting that rural restaurants might be able to contribute to the conservation of these species. The thirteen species of restaurant-visiting birds belonged to five monophyletic clades. Ninety percent of all restaurants had, as their predominant species, birds from either Clade A (Passeridae, Motacillidae, Fringillidae) or Clade C (Corvidae). Statistical testing revealed that Clade A and Clade C were distributed differently in environments along the urban-rural gradient. At all spatial scales measured, birds of Clade C were predominant at the majority of restaurants in urban areas, while birds of Clade A were the predominant clade at the majorit

The historical account of Aztec Emperor Auitztol's introduction of the great-tailed grackle Quiscalus mexicanus into the Valley of Mexico (1486–1502) is significant because it documents human translocation of wild birds in Mexico over 500 years ago, before the Spanish Conquest of that land. In the present paper, which defends the account from writings that dispute it, I first review the evidence of how the account was obtained and show that its many details are consistent with what is known from other sources about both the great-tailed grackle and the Aztecs (Nahuas). I then review and examine all published criticisms of the account and explain in detail why they are wrong. The critics have to date presented no persuasive evidence to support their speculation that the Aztecs confused, or might have confused, a natural invasion for an introduction. In contrast to these critics, Bernardino de Sahagún’s research group in the 1500s presented a highly credible, peer-reviewed historical account that documented Aztec introduction of the great-tailed grackle. The pioneering work of these Renaissance Mexican scholars continues to stand as one of the most important records of invasive alien species introduction in ancient times.

BACKGROUND: Over the past quarter century, the incidence of tick-borne encephalitis (TBE) has increased in most European nations. However, the number of humans stricken by the disease varies from year to year. A method for predicting major increases and decreases is needed. METHODS: We assembled a 25-y database (1984-2008) of the number of human TBE victims and wildlife and climate data for the Stockholm region of Sweden, and used it to create easy-to-use mathematical models that predict increases and decreases in the number of humans stricken by TBE. RESULTS: Our best model, which uses December precipitation and mink (Neovison vison, formerly Mustela vison) bagging figures, successfully predicted every major increase or decrease in TBE during the past quarter century, with a minimum of false alarms. However, this model was not efficient in predicting small increases and decreases. CONCLUSIONS: Predictions from our models can be used to determine when preventive and adaptive programmes should be implemented. For example, in years when the frequency of TBE in humans is predicted to be high, vector control could be intensified where infested ticks have a higher probability of encountering humans, such as at playgrounds, bathing lakes, barbecue areas and camping facilities. Because our models use only wildlife and climate data, they can be used even when the human population is vaccinated. Another advantage is that because our models employ data from previously-established databases, no additional funding for surveillance is required.

The natural reservoir of influenza A virus is waterfowl, particularly dabbling ducks (genus Anas). Although it has long been assumed that waterfowl are asymptomatic carriers of the virus, a recent study found that low-pathogenic avian influenza (LPAI) infection in Bewick's swans (Cygnus columbianus bewickii) negatively affected stopover time, body mass and feeding behaviour. In the present study, we investigated whether LPAI infection incurred ecological or physiological costs to migratory mallards (Anas platyrhynchos) in terms of body mass loss and staging time, and whether such costs could influence the likelihood for long-distance dispersal of the avian influenza virus by individual ducks. During the autumn migrations of 2002-2007, we collected faecal samples (n=10918) and biometric data from mallards captured and banded at Ottenby, a major staging site in a flyway connecting breeding and wintering areas of European waterfowl. Body mass was significantly lower in infected ducks than in uninfected ducks (mean difference almost 20g over all groups), and the amount of virus shed by infected juveniles was negatively correlated with body mass. There was no general effect of infection on staging time, except for juveniles in September, in which birds that shed fewer viruses stayed shorter than birds that shed more viruses. LPAI infection did not affect speed or distance of subsequent migration. The data from recaptured individuals showed that the maximum duration of infection was on average 8.3 days (s.e. 0.5), with a mean minimum duration of virus shedding of only 3.1 days (s.e. 0.1). Shedding time decreased during the season, suggesting that mallards acquire transient immunity for LPAI infection. In conclusion, deteriorated body mass following infection was detected, but it remains to be seen whether this has more long-term fitness effects. The short virus shedding time suggests that individual mallards are less likely to spread the virus at continental or interconti

When humans, pets and livestock walk along roads, they may encounter questing ticks and tick-borne pathogens. A new field of environmental science called road ecology can help researchers study the complex epidemiology of tick-borne diseases in the unique roadside environment. This paper reviews some of the important ways that roads alter the distribution, abundance and behaviour of wildlife species that are involved in the enzootic cycles of tick-borne diseases. Compared to the surrounding landscape, roadways often constitute a different environment and hence there is no assurance that disease risk along roads will be the same as in the adjacent landscape, or that disease control measures taken in the surrounding landscape will work in the adjacent roadway. Since roadways have their own special ecological conditions, are used extensively by the human populace and play strategic roles in community security, we believe that roadways should be one of the habitats where tick-borne diseases are studied. It is amazing that at this late period of human history, epidemiological research along such important corridors has been almost completely ignored.

Analysing datasets from hunting statistics and human cases of tick-borne encephalitis (TBE), we found a positive correlation between the number of human TBE cases and the number of red fox (Vulpes vulpes). Time lags were also present, indicating that high numbers of red fox in 1 y translated into high numbers of human TBE cases the following y. Results for smaller predators were mixed and inconsistent. Hares and grouse showed negative correlations with human TBE cases, suggesting that they might function as dilution hosts. Combining our findings with food web dynamics, we hypothesize a diversity of possible interactions between predators and human disease - some predators suppressing a given disease, others enhancing its spread, and still others having no effect at all. Larger-sized predators that suppress red fox numbers and activity (i.e. wolf, Canis lupus; European lynx, Lynx lynx) were once abundant in our study area but have been reduced or extirpated from most parts of it by humans. We ask what would happen to red foxes and TBE rates in humans if these larger predators were restored to their former abundances.

Farmers around the world have been urged to eliminate barn swallows (Hirundo rustica) from their buildings, based on the unproven assumption that these birds amplify and spread Salmonella to livestock, humans, and stored food. However, we tested over 500 barn swallows in Sweden and found no evidence that they carry Salmonella. Our results cast doubt on the hypothesis that barn swallows are competent reservoirs of Salmonella and suggest that their role, if any, is limited to being accidental hosts of the bacterium.

Oseltamivir is the main antiviral for treatment and prevention of pandemic influenza. The increase in oseltamivir resistance reported recently has therefore sparked a debate on how to use oseltamivir in non pandemic influenza and the risks associated with wide spread use during a pandemic. Several questions have been asked about the fate of oseltamivir in the sewage treatment plants and in the environment. We have assessed the fate of oseltamivir and discuss the implications of environmental residues of oseltamivir regarding the occurrence of resistance. A series of batch experiments that simulated normal sewage treatment with oseltamivir present was conducted and the UV-spectra of oseltamivir were recorded. Findings: Our experiments show that the active moiety of oseltamivir is not removed in normal sewage water treatments and is not degraded substantially by UV light radiation, and that the active substance is released in waste water leaving the plant. Our conclusion is that a ubiquitous use of oseltamivir may result in selection pressures in the environment that favor development of drug-resistance.

Analysing datasets from hunting statistics and human cases of tick-borne encephalitis (TBE), we found a positive correlation between the number of human TBE cases and the number of red fox (Vulpes vulpes). Time lags were also present, indicating that high numbers of red fox in 1 y translated into high numbers of human TBE cases the following y. Results for smaller predators were mixed and inconsistent. Hares and grouse showed negative correlations with human TBE cases, suggesting that they might function as dilution hosts. Combining our findings with food web dynamics, we hypothesize a diversity of possible interactions between predators and human disease - some predators suppressing a given disease, others enhancing its spread, and still others having no effect at all. Larger-sized predators that suppress red fox numbers and activity (i.e. wolf, Canis lupus; European lynx, Lynx lynx) were once abundant in our study area but have been reduced or extirpated from most parts of it by humans. We ask what would happen to red foxes and TBE rates in humans if these larger predators were restored to their former abundances.

In this study, we present a novel method to isolate and enrich low concentrations of Campylobacter pathogens. This method, Acanthamoeba-Campylobacter coculture (ACC), is based on the intracellular survival and multiplication of Campylobacter species in the free-living protozoan Acanthamoeba polyphaga. Four of the Campylobacter species relevant to humans and livestock, Campylobacter jejuni, C. coli, C. lari, and C. hyointestinalis, were effectively enriched by the coculture method, with growth rates comparable to those observed in other Campylobacter enrichment media. Studying six strains of C. jejuni isolated from different sources, we found that all of the strains could be enriched from an inoculum of fewer than 10 bacteria. The sensitivity of the ACC method was not negatively affected by the use of Campylobacter-selective antibiotics in the culture medium, but these were effective in suppressing the growth of seven different bacterial species added at a concentration of 10(4) CFU/ml of each species as deliberate contamination. The ACC method has advantages over other enrichment methods as it is not dependent on a microaerobic milieu and does not require the use of blood or other oxygen-quenching agents. Our study found the ACC method to be a promising tool for the enrichment of Campylobacter species, particularly from water samples with low bacterial concentrations.

At Bird Island, South Georgia, we studied the effects of the tick Ixodes uriae on survival of chicks at two colonies of the black-browed albatross Diomedea melanophrys, one where most chicks were infested with ticks, the other where most chicks were tick-free. When the two colonies were compared, it was found that the colony heavily-infested with ticks had significantly greater chick mortality than the colony lightly-infested with ticks. However, within each of the two colonies, there was no significant difference in survival between chicks with ticks and those without ticks.