Nuclear weak interaction rates during stellar evolution and collapse

Nuclear weak interaction rates, including electron and positron emission rates, and continuum electron and positron capture rates , as well as the associated v and –/v energy loss rates are calculated on a detailed grid of temperature and density for the free nucleons and 226 nuclei with masses between A = 21 and 60. Gamow-Teller and Fermi discrete-state transition matrix element systematics and the Gamow-Teller T^< →/← T^> resonance transitions are discussed in depth and are implemented in the stellar rate calculations. Results of the calculations are presented on an abbreviated grid of temperature and density and comparison is made to terrestrial weak transition rates where possible. Neutron shell blocking of allowed electron capture on heavy nuclei during stellar core collapse is discussed along with several unblocking mechanisms operative at high temperature and density. The results of one-zone collapse calculations are presented which suggest that the effect of neutron shell blocking is to produce a larger core lepton fraction at neutrino trapping which leads to a larger inner-core mass and hence a stronger post-bounce shock.

Temporal trends (2000–2011) and influences on fishery-independent catch rates for loggerhead sea turtles (Caretta caretta) at an important coastal foraging region in the southeastern United States

Seasonal trawling was conducted randomly in coastal (depths of 4.6–17 m) waters from St. Augustine, Florida, (29.9°N) to Winyah Bay, South Carolina (33.1°N), during 2000–03, 2008–09, and 2011 to assess annual trends in the relative abundance of sea turtles. A total of 1262 loggerhead sea turtles (Caretta caretta) were captured in 23% (951) of 4207 sampling events. Capture rates (overall and among prevalent 5-cm size classes) were analyzed through the use of a generalized linear model with log link function for the 4097 events that had complete observations for all 25 model parameters. Final models explained 6.6% (70.1–75.0 cm minimum straight-line carapace length [SCLmin]) to 14.9% (75.1–80.0 cm SCLmin) of deviance in the data set. Sampling year, geographic subregion, and distance from shore were retained as significant terms in all final models, and these terms collectively accounted for 6.2% of overall model deviance (range: 4.5–11.7% of variance among 5-cm size classes). We retained 18 parameters only in a subset of final models: 4 as exclusively significant terms, 5 as a mixture of significant or nonsignificant terms, and 9 as exclusively nonsignificant terms. Four parameters also were dropped completely from all final models. The generalized linear model proved appropriate for monitoring trends for this data set that was laden with zero values for catches and was compiled for a globally protected species. Because we could not account for much model deviance, metrics other than those examined in our study may better explain catch variability and, once elucidated, their inclusion in the generalized linear model should improve model fits.

Seston capture by Hydropsyche siltalai and the accuracy of capture efficiency estimates

1. Suspension feeding by caseless caddisfly larvae (Trichoptera) constitutes a major pathway for energy flow, and strongly influences productivity, in streams and rivers. 2. Consideration of the impact of these animals on lotic ecosystems has been strongly influenced by a single study investigating the efficiency of particle capture of nets built by one species of hydropsychid caddisfly. 3. Using water sampling techniques at appropriate spatial scales, and taking greater consideration of local hydrodynamics than previously, we examined the size-frequency distribution of particles captured by the nets of Hydropsyche siltalai. Our results confirm that capture nets are selective in terms of particle size, and in addition suggest that this selectivity is for particles likely to provide the most energy. 4. By incorporating estimates of flow diversion around the nets of caseless caddisfly larvae, we show that capture efficiency (CE) is considerably higher than previously estimated, and conclude that more consideration of local hydrodynamics is needed to evaluate the efficiency of particle capture. 5. We use our results to postulate a mechanistic explanation for a recent example of interspecific facilitation, whereby a reduction of near-bed velocities seen in single species monocultures leads to increased capture rates and local depletion of seston within the region of reduced velocity.

Maximising trapping efficiency in reptile surveys : the role of seasonality, weather conditions and moon phase on capture success

Context : Designing an appropriate survey protocol requires understanding of how capture rates of target species may be influenced by factors other than on-ground abundance, such as weather conditions or seasonality. This is particularly relevant for ectotherms such as reptiles, as activity can be affected by environmental conditions such as ambient temperature.
Aims : The present study examines factors affecting capture success of reptiles in semi-arid environments of southern Australia, and addresses the following two main questions: (1) what is the influence of weather and seasonal factors on capture rates of reptiles, and (2) what are the implications for developing an effective protocol for reptile surveys?
Methods : We surveyed reptiles using pitfall traps in spring and summer of 2006/07 and 2007/08 at sites (n = 280) throughout the Murray Mallee region of south-eastern Australia. We used mixed-effect regression models to investigate the influence of seasonal and weather-related variables on species’ capture success.
Key results : Total captures of reptiles, and the likelihood of capture of 15 reptile species, increased with rising daily temperature. Greater numbers of individual species were captured during spring than in summer, even though temperatures were cooler. This probably reflects greater levels of activity associated with breeding. Several species were more likely to be captured when maximum or minimum daily temperatures exceeded a certain level (e.g. Lerista labialis, Delma australis, Nephrurus levis). Other factors, such as rainfall and moon phase, also influenced capture success of some species.
Conclusions : Surveys for reptiles in semi-arid environments are likely to capture the greatest diversity of species on warm days in late spring months, although surveys on hot days in summer will enhance detection of particular species (e.g. Morethia boulengeri, Varanus gouldii). We recommend trapping during periods with maximum temperatures exceeding 25–30C and minimum overnight temperatures of 15C. Finally, trapping during rainfall and full-moon events will maximise chances of encountering species sensitive to these variables (blind snakes and geckoes).
Implications : Selecting the most favourable seasonal and weather conditions will help ensure that reptile surveys maximise the likelihood of capturing the greatest diversity of reptiles, while minimising trap-effort required.

Improving precision and reducing bias in biological surveys: estimating false-negative error rates

The use of presence/absence data in wildlife management and biological surveys is widespread. There is a growing interest in quantifying the sources of error associated with these data. We show that false-negative errors (failure to record a species when in fact it is present) can have a significant impact on statistical estimation of habitat models using simulated data. Then we introduce an extension of logistic modeling, the zero-inflated binomial (ZIB) model that permits the estimation of the rate of false-negative errors and the correction of estimates of the probability of occurrence for false-negative errors by using repeated. visits to the same site. Our simulations show that even relatively low rates of false negatives bias statistical estimates of habitat effects. The method with three repeated visits eliminates the bias, but estimates are relatively imprecise. Six repeated visits improve precision of estimates to levels comparable to that achieved with conventional statistics in the absence of false-negative errors In general, when error rates are less than or equal to50% greater efficiency is gained by adding more sites, whereas when error rates are >50% it is better to increase the number of repeated visits. We highlight the flexibility of the method with three case studies, clearly demonstrating the effect of false-negative errors for a range of commonly used survey methods.

On the context-dependent scaling of consumer feeding rates

The stability of consumer-resource systems can depend on the form of feeding interactions (i.e. functional responses). Size-based models predict interactions - and thus stability - based on consumer-resource size ratios. However, little is known about how interaction contexts (e.g. simple or complex habitats) might alter scaling relationships. Addressing this, we experimentally measured interactions between a large size range of aquatic predators (4-6400 mg over 1347 feeding trials) and an invasive prey that transitions among habitats: from the water column (3D interactions) to simple and complex benthic substrates (2D interactions). Simple and complex substrates mediated successive reductions in capture rates - particularly around the unimodal optimum - and promoted prey population stability in model simulations. Many real consumer-resource systems transition between 2D and 3D interactions, and along complexity gradients. Thus, Context-Dependent Scaling (CDS) of feeding interactions could represent an unrecognised aspect of food webs, and quantifying the extent of CDS might enhance predictive ecology.

An objective study of acid reflux and cough in children using an ambulatory pHmetry-cough logger

Objective There are no objective ambulatory studies on the temporal relationship between reflux and cough in children. Commercial pHmetry loggers have slow capture rates (0.25 Hz) that limit objective quantification of reflux and cough. The authors aimed to evaluate if there is a temporal association between cough and acid pH in ambulatory children with chronic cough. setting and patients The authors studied children (aged <14 years) with chronic cough, suspected of acid reflux and considered for pHmetry using a specifically built ambulatory pHmetry–cough logger that enabled the simultaneous ambulatory recording of cough and pH with a fast (10 Hz) capture rate. Main outcome measures Coughs within (before and after) 10, 30, 60 and 120 s of a reflux episode (pH<4 for >0.5 s). Results Analysis of 5628 coughs in 20 children. Most coughs (83.9%) were independent of a reflux event. Cough–reflux (median 19, IQR 3–45) and reflux–cough (24.5, 13–51) sequences were equally likely to occur within 120 s. Within the 10 and 30 s time frame, reflux–cough (10 s=median 2.5, IQR 0–7.25; 30 s=6.5, 1.25–22.25) sequences were significantly less frequent than reflux–no cough (10 s=27, IQR 15–65; 30 s=24.5, 14.5–55.5) sequences, (p=0.0001 and p=0.001, respectively). No differences were found for 60 and 120 s time frame. Cough–reflux sequence (median 1.0, IQR 0–8) within 10 s was significantly less (p=0.0001) than no cough–reflux sequences (median 29.5, 15–67), within 30 s (p=0.006) and 60 s (p=0.048) but not within 120 s (p=0.47). Conclusions In children with chronic cough and suspected of having gastro-oesophageal reflux disease, the temporal relationship between acid reflux and cough is unlikely causal.

Trapping success and population analysis of Siren lacertina and Amphiuma means

Siren and Amphiuma are two poorly known genera of aquatic salamanders that occur in the Southeastern United States. A primarily bottom-dwelling existence makes these salamanders difficult to detect with conventional sampling methodologies. Therefore, the current status of their populations is unknown. I compared the capture success of modified crayfish traps and plastic minnow traps in capturing these salamanders. In addition, a mark-recapture study of S. lacertina (Greater siren) and A. means (Two-toed amphiuma) was conducted at Okefenokee National Wildlife Refuge (southern Georgia) and at Katharine Ordway Preserve (north-central Florida) from August 2001 until September 2002. Crayfish traps were much more successful than minnow traps in catching siren and amphiuma. Crayfish traps yielded 270 captures for an overall capture success of 16%, whereas minnow traps yielded only 13 captures for an overall success rate of 0.05%. In addition, several marking techniques were evaluated, and of these, only passive integrated transponder (PIT) tags were retained for the duration of the study. Therefore, I recommend this marking technique for long-term monitoring of S. lacertina and A. means. Several variables were found to have significant effects on capture rates of salamanders. A. means were most often captured in summer and the number of captures was positively correlated with water temperature, water level, and rainfall. S. lacertina were most often captured during winter and spring. Number of captures was negatively correlated with water temperature, while no relationship was found with water level or rainfall. Trap day and baiting had no significant effect on number of A. means or S. lacertina captured. Recapture probabilities of both species were low, 0.025-0.03 for S. lacertina and 0.08-0.11 for A. means. Monthly survival rates were high, 0.77-0.97 for A. means and 0.88-1.00 for S. lacertina. Density estimates of 1.3 salamanders/m2 (S. lacertina) and 0.28 salamanders/m2 (A. means) were obtained for Lake Suggs using Jolly-Seber models. Siren and amphiuma make up a substantial part of wetland biomass and can impact many other wetland species. Thus, more attention must be focused on evaluating and monitoring their populations.

Methodologies for a sustainable development of estuarine ecosystems

As zonas costeiras, estuarinas e lagunares são consideradas áreas muito produtivas e dotadas de grande biodiversidade sendo, por isso, consideradas de elevado valor ecológico e económico. No entanto, nas últimas décadas tem vindo a verificar-se um aumento da contaminação destes ecossistemas como resultado de diversas actividades antrópicas. As abordagens actualmente disponíveis para avaliação do impacto da poluição em ecossistemas estuarinos e lagunares apresentam diversos tipos de lacunas, pelo que é importante desenvolver metodologias mais eficazes com organismos autóctones. Neste contexto, o objectivo central desta dissertação consistiu em desenvolver e validar métodos ecologicamente relevantes para avaliação da contaminação estuarina e dos seus efeitos, utilizando o góbio-comum (Pomatoschistus microps), quer como organismo-teste quer como espécie sentinela, devido à importante função que desempenha nas cadeias tróficas de diversos estuários da costa Portuguesa. A Ria de Aveiro foi seleccionada como área de estudo principalmente pelo facto de possuir zonas com diferentes tipos de contaminação predominante e de haver conhecimento científico de base abundante e de elevada qualidade sobre este ecosistema. Na primeira fase do estudo, foram investigados os efeitos agudos de dois hidrocarbonetos aromáticos policíclicos (HAPs) (benzo[a]pireno e antraceno), de um fuel-óleo e de dois metais (cobre e mercúrio) em P. microps, utilizando ensaios laboratoriais baseados em biomarcadores e em parâmetros comportamentais, os quais foram avaliados utilizando um dispositivo expressamente desenvolvido para o efeito, designado por speed performance device (SPEDE). Como biomarcadores foram utilizados parâmetros envolvidos em funções fisiológicas determinantes para a sobrevivência e desempenho dos animais (neurotransmissão, obtenção de energia, destoxificação e defesas anti-oxidantes), nomeadamente a actividade das enzimas acetilcolinesterase, lactato desidrogenase, CYP1A1, glutationa S-transferases, glutationa reductase, glutationa peroxidase, superóxido dismutase, catalase, tendo ainda sido determinados os níveis de peroxidação lipídica como indicador de danos oxidativos. De forma global, os resultados indicaram que os agentes e a mistura testados têm a capacidade de interferir com a função neurológica, de alterar as vias utilizadas para obtenção de energia celular, induzir as defesas antioxidantes e, no caso do cobre e do mercúrio, de causarem peroxidação lipídica. Foram ainda obtidas relações concentração-resposta a nível dos parâmetros comportamentais testados, nomeadamente a capacidade de nadar contra a corrente e a distância percorrida a nadar contra o fluxo de água, sugerindo que os agentes testados podem, por exemplo, diminuir a capacidade de fuga aos predadores, as probabilidades de captura de presas e o sucesso reprodutivo. Na segunda fase, tendo sido já adaptadas técnicas para determinação de vários biomarcadores em P. microps e estudada a sua resposta a dois grupos de poluentes particularmente relevantes em ecossistemas estuarinos e lagunares (metais e HAPs), foi efectuado um estudo de monitorização utilizando P. microps como bioindicador e que incluiu diversos parâmetros ecológicos e ecotoxicológicos, nomedamente: 20 parâmetros indicativos da qualidade da água e do sedimento, concentração de 9 metais em sedimentos e no corpo de P. microps, 8 biomarcadores e 2 índices de condição na espécie seleccionada. A amostragem foi efectuada em quatro locais da Ria de Aveiro, um considerado como referência (Barra) e três com diferentes tipos predominantes de contaminação (Vagueira, Porto de Aveiro e Cais do Bico), sazonalmente, durante um ano. Os resultados obtidos permitiram uma caracterização ecotoxicológica dos locais, incluindo informação sobre a qualidade da água, concentrações de contaminantes ambientais prioritários nos sedimentos e nos tecidos de P. microps, capacidade desta espécie para bioacumular metais, efeitos exercidos pelas complexas misturas de poluentes presentes em cada uma das zonas de amostragem nesta espécie e possíveis consequências para a população. A análise multivariada permitiu analisar de forma integrada todos os resultados, proporcionando informação que não poderia ser obtida analisando os dados de forma compartimentalizada. Em conclusão, os resultados obtidos no âmbito desta dissertação indicam que P. microps possui características adequadas para ser utilizado como organismoteste em ensaios laboratoriais (e.g. abundância, fácil manutenção, permite a determinação de diferentes tipos de critérios de efeito utilizando um número relativamente reduzido de animais, entre outras) e como organismo sentinela em estudos de monitorização da poluição e da qualidade ambiental, estando portanto de acordo com estudos de menor dimensão previamente efectuados. O trabalho desenvolvido permitiu ainda adaptar a P. microps diversas técnicas bioquímicas vulgarmente utilizadas como biomarcadores em Ecotoxicologia e validá-las quer no laboratório quer em cenários reais; desenvolver um novo bioensaio, utilizando um dispositivo de teste especialmente concebido para peixes epibentónicos baseado na performance natatória de uma espécie autóctone e em biomarcadores; relacionar os efeitos a nível bioquímico com parâmetros comportamentais que ao serem afectados podem reduzir de forma drástica e diversificada (e.g. aumento da mortalidade, diminuição do sucesso reprodutivo, redução do crescimento) a contribuição individual para a população. Finalmente, foi validada uma abordagem multidisciplinar, combinando metodologias ecológicas, ecotoxicológicas e químicas que, quando considerada de forma integrada utilizando análises de estatística multivariada, fornece informação científica da maior relevância susceptível de ser utilizada como suporte a medidas de conservação e gestão em estuários e sistemas lagunares.

Habitat Split as a Cause of Local Population Declines of Amphibians with Aquatic Larvae

Most amphibian species have biphasic life histories and undergo an ontogenetic shift from aquatic to terrestrial habitats. In deforested landscapes, streams and forest fragments are frequently disjunct, jeopardizing the life cycle of forest-associated amphibians with aquatic larvae. We tested the impact of habitat split-defined as human-induced disconnection between habitats used by different life-history stages of a species-on four forest-associated amphibian species in a severely fragmented landscape of the Brazilian Atlantic Forest. We surveyed amphibians in forest fragments with and without streams (referred to as wet and dry fragments, respectively), including the adjacent grass-field matrix. Our comparison of capture rates in dry fragments and nearby streams in the matrix allowed us to evaluate the number of individuals that engaged in high-risk migrations through nonforested habitats. Adult amphibians moved from dry fragments to matrix streams at the beginning of the rainy season, reproduced, and returned at the end of the breeding period. Juveniles of the year moved to dry fragments along with adults. These risky reproductive migrations through nonforested habitats that expose individuals to dehydration, predation, and other hazards may cause population declines in dry fragments. Indeed, capture rates were significantly lower in dry fragments compared with wet fragments. Declining amphibians would strongly benefit from investments in the conservation and restoration of riparian vegetation and corridors linking breeding and nonbreeding areas.

Effect of Phytophthora cinnamomi on the habitat utilization of Antechinus stuartii in a Victorian forest

Phytophthora cinnamomi (Cinnamon fungus) is a pathogenic soil fungus which infects plant communities along the south-eastern coast of Australia, and the south-western corner of Western Australia. The symptoms of this disease include chlorosis, death of branches (ie. ‘dieback’), retarded growth and the eventual death of infected plants. This leads to devastating effects upon plant communities by altering both the structural and floristic characteristics of these communities. Small mammal species are dependent on specific features of their habitat such as vegetation structure and floristics. This thesis investigated alterations to the habitat of the insectivorous marsupial mouse, Antechinus stuartii, due to the presence of P. cinnamomi. The study was undertaken in an area of an open forest in the Brisbane Ranges, Victoria. Significant changes were found in both the floristic composition and structure of the vegetation at study sites infected with P, cinnamomi, compared to uninfected sites. The habitat utilization by A. stuartii of uninfected and infected vegetation was investigated using live trapping and radio-telemetric techniques. Capture rates were higher at sites uninfected by P. cinnamomi, and both male and females selected areas free from infection. Home range areas of males were significantly larger than those of females as assessed by telemetry. Both sexes spent a high proportion of time in areas dominated by Xanthorrhoea australis (Austral grass tree). There were significant relationships between the abundance of A. stuartii and the denseness of vegetation above 1 metre in height, and in particular, the proportion of cover afforded by X. australis. There were no significant differences in the cover of Eucalyptus spp. between uninfected and infected sites, but there were significantly more nest hollows in infected areas. The abundance of invertebrates was examined using pitfall traps. There were no significant differences in the abundance of the larger invertebrate taxa at infected and uninfected sites, but higher abundances of some micro-invertebrate groups in infected areas were recorded. The most likely factors considered to be influential in the habitat selection of A. stuartii were vegetation structure, and the presence of X. australis. To assess whether these factors were important the leaves of X. australis were removed with a brushcutter, to mimic the early effects of infection with P. cinnamomi. Animals did not respond to the alteration of vegetation structure in the short term (3-4 days). Longer-term experiments are required to assess the habitat utilization of A. stuartii at different periods following habitat manipulation. The implications of the presence of P. cinnamomi on the conservation of fauna are discussed. The destructive nature of the pathogen, and the slow rate of recovery from the disease, means that P. cinnamomi can be considered a threatening process to plant communities and the fauna that reside within that habitat. Future management of this disease within natural areas must therefore be cognisant of the potential of P. cinnamomi to significantly affect faunal as well as vegetative communities.

Effects of phytophthora cinnamomi on heathland flora and fauna of the Eastern Otway Ranges

The plant pathogen, Phytophthora dnnamomi, is a cause of dieback disease observed in sclerophyll vegetation in Australia, The effects of P. dnnamomi on flora and fauna were studied at two locations in heathland vegetation near the coastal town of Anglesea, Victoria. The pathogen was isolated from soils beneath diseased heathland plants. The extent of diseased vegetation was assessed by the presence and absence of highly sensitive indicator species, Xanthorrhoea australis and hopogon ceratophyllus. The characteristics of heathland vegetation exhibiting dieback disease associated with the presence of P. dnnamomi were investigated. Plant species richness was similar between diseased and non-diseased areas however diseased areas were characterised by significant declines in the cover and frequency of susceptible species, increases in resistant species and increases in percent cover of open ground. Compared to non-diseased areas, diseased areas exhibited fewer shrub species and decreased shrub cover. The percentage cover and number of species of sedges, lilies and grasses were higher in diseased areas. Structural differences were significant between 0-0.6 m with decreased cover of vegetation in diseased areas. Differences in structure between diseased and non-diseased areas were not as great as expected due to increases in the cover of resistant species. A number of regenerating X australis were observed in post-disease areas. Cluster analysis of floristic data could clearly separate diseased and non-diseased trap stations. The population dynamics and habitat use of eight small mammal species present were compared in diseased and non-diseased areas using trapping and radio-tracking techniques. The number of small mammal species captured in post-disease areas was significantly lower than non-diseased areas. Mean captures of Antechinus stuartii and Rattus fiisdpes were significantly lower in diseased areas on Grid B. Mean captures of Rattus lutreolus were significantly lower in diseased areas on both study grids. Significant differences were not observed in every season over the two year study period. Radio tracking revealed more observations of Sminthopsis leucopus in non-diseased vegetation than in diseased. Cercartetus nanus was frequently observed to utilise the disease susceptible X. australis for nesting. At one location, the recovery of vegetation and small mammal communities in non-diseased and diseased vegetation after fuel reduction burning was monitored for three years post-fire. Return of plant species after fire in both disease classes were similar, reaching 75% of pre-fire richness after three years. Vegetation cover was slower to return after fire in diseased areas. Of the seven small mammal species captured pre-fire, five were regularly captured in the three years after fire. General linear model analysis revealed a significant influence of disease on capture rates for total small mammals before fire and a significant influence of fire on capture rates for total small mammals after fire. After three years, the influence of fire on capture rates was reduced no significant difference was detected between disease classes. Measurements of microclimate indicate that diseased, burnt heathland was likely to experience greater extremes of temperature and wind speed. Seeding of diseased heathland with X. australis resulted in the establishment of seedlings of this sensitive species. The reported distributions of the mamma] species in Victoria were analysed to determine which species were associated with the reported distribution of dieback disease. Twenty-two species have more than 20% of their known distribution in diseased areas. Five of these species, Pseudomys novaehollandiae, Pseudomys fumeust Pseudomys shortridgei, Potorous longipes and Petrogale pencillata are rare or endangered in Victoria. Four of the twenty-two species, Sminthopsis leucopus, Isoodon obesulus, Cercartetus nanus and Rottus lutreolus am observed in Victorian heathlands. Phytophthora cinnamomi changes both the structure and floristics of heathland vegetation in the eastern Qtway Ranges. Small mammals respond to these changes through decreased utilisation of diseased heathland. The pathogen threatens the diversity of species present and future research efforts should be directed towards limiting its spread and rehabilitating diseased areas.

Why do Gull-billed Terns Gelochelidon nilotica feed on fiddler crabs Uca tangeri in Guinea-Bissau?

Gull-billed Terns Gelochelidon nilotica wintering in Guinea Bissau mainly fed on fiddler crabs Uca tangeri and were occasionally seen feeding on fish and locusts. As fiddler crabs have a low energy content, terns need a large gross intake to meet daily energy demands. Fiddler crabs also have a low ratio of digestible flesh to exoskeleton, and therefore tern food intake may be limited by gut capacity. Activity budgets of Gullbilled Terns feeding on fiddler crabs showed that a considerable part of the time was spent resting. The duration of resting intervals increased with energy intake and was positively correlated with the metabolisable energy content of the crab eaten, suggesting that resting periods were required for a proper digestion. The poor quality of fiddler crabs was offset by high capture rates. So daily energy expenditure of the terns could easily be met by feeding on fiddler crabs. Even when resting pauses were included in foraging time, foraging for only 1.5 hours on fiddler crabs satisfied the terns’ daily energy demands. Instead, feeding on energy-rich fish would require about 2.5 hours to satisfy daily energy demands. Compared to the more specialised piscivorous Little Tern Sternula albifrons and Sandwich Tern Sterna sandvicensis, capture rate of fish was poor in Gull-billed Terns. From an energetic point of view, wintering Gull-billed Terns feeding on fiddler crabs seem to have an easy living in Guinea Bissau.

Field evaluation of melolure, a formate analogue of cuelure, and reassessment of fruit fly species trapped in Sydney, New South Wales, Australia

In Australia, tephritids are usually attracted to either cuelure or methyl eugenol. Methyl eugenol is a very effective lure, but cuelure is less effective likely due to low volatility. A new formate analogue of cuelure, melolure, has increased volatility, resulting in improved efficacy with the melon fruit fly, Bactrocera cucurbitae Coquillett. We tested the efficacy of melolure with fruit fly species in Sydney as part of the National Exotic Fruit Fly Monitoring programme. This monitoring programme has 71 trap sites across Sydney, with each trap site comprising separate Lynfield traps containing either cuelure, methyl eugenol, or capilure lure. In 2008, an additional Lynfield trap with melolure plugs was added to seven sites. In 2009 and 2010, an additional Lynfield trap with melolure wicks was added to 11 trap sites and traps were monitored fortnightly for 2 yr. Capture rates for melolure traps were similar to cuelure traps for Dacus absonifacies (May) and Dacus aequalis (Coquillet), but melolure traps consistently caught fewer Bactrocera tryoni (Froggatt) than cuelure traps. However, trap sites with both a cuelure and melolure traps had increased capture rates for D. absonifacies and D. aequalis, and a marginally significant increase for B. tryoni. Melolure plugs were less effective than melolure wicks, but this effect may be related to lure concentration. The broader Bactrocera group species were attracted more to cuelure than melolure while the Dacus group species were attracted more to melolure than cuelure. There is no benefit in switching from cuelure to melolure to monitor B. tryoni, the most important fruit fly pest in Australia.

Biologia populacional comparada de duas espécies de heliconius (Lepidoptera: Nymphalidae) em um ambiente sazonal de floresta atlântica do nordeste brasileiro

Tropical environments often face strong seasonal variations in climate, such as alternate periods of dry and rain, that may often be important influence in the annual X the organisms lives. Here we assess how population dynamics of two butterfly species (Heliconius erato and Heliconius mepomene) respond to environmental and seasonal variations. A mark-release-recapture study carried out in an Atlantic forest reserve, 15 Km from Natal, Rio Grande do Norte, Brazil, for 3 years, during the dry and rainy season, with three visits weekly done. Information such as species, wing lenght, site of capture, pollen load and phenotype (number of spots) (in H. erato only) were noted for each capture. Seasonal variation exists in capture rates of the two species, with great capture rates during the rainy season. Despite finding differences in the mean density of individuals of the two species among the different collection areas, this difference was only significant between floodplain and central areas, and no influence of seasonality was observed in the mean density between the areas. Seasonality in wing size was only observed for H. erato, with larger wings during the rainy season. Females carried larger pollen loads than males both species, but species were similar. Only males differed seasonally, with larger pollen loads during the rainy season. The distribution of the number of wing spots did not vary between the dry and rainy seasons, and the number of spots in males and females was similar. Therefore, we conclude that there was a strong influence of seasonal variation in the population dynamic of the two Heliconius species, as well as in several aspects of their biology