Nest site selection and reproductive parameters of the threatened Atlantic Royal Flycatcher(Onychorhynchus swainsoni)and their significance for conservation

Background:Patterns of rarity can be explained by reproductive rates,levels of endemism,and habitat specificity,and knowledge on these parameters is important to understand the levels of vulnerability of each species and to formulate conservation strategies.Here,we studied nest-site selection and breeding biology of the Atlantic Royal Flycatcher(Onychorhynchus swainsoni),a poorly known vulnerable bird endemic to the Brazilian Atlantic Forest.Methods:We addressed nest site selection in three different levels:first,we searched for nests near and far from water to investigate whether birds could select water proximities to construct nests;second,we examined if they could select certain streams in detriment of others,and we analyzed the characteristics of used and non-used streams,and third,in streams in which nests were found,we addressed nest site selectivity by comparing a number of parameters between nest sites and random sites.Further,we provide information on breeding biology parameters related to annual fecundity.Results:During five breeding seasons,we found 23 nests in a well-preserved forest continuum.All of the nests were constructed above water,and they were found in streams that were about 4 m in width,instead of smaller streams with about 1.5 m in width.Modeling analyses revealed that within the used streams,nests were constructed in sites with lower vegetation density in relation to random points,while stream width,water speed,and canopy cover presented no significant correlation.Atlantic Royal Flycatchers in our study had a 22-day incubation period and 24 to 27-day nestling period.Overall nest survival was comparatively high(62%),but clutch size was small(N=2 eggs)and Along the nesting streams,we found an average of 1.62±0.07 breeding pairs/km.Conclusions:These data suggest that nesting habitat specificity and low annual fecundity are among the factors contributing to the rarity of the Atlantic Royal Flycatcher in large forest continuums and to its absence in fragmented environments.It reinforces the importance of large well-preserved forest continuums for the conservation of habitat specialist Atlantic Forest bird species.

Short-term forecast in the early stage of the COVID-19 outbreak in Italy. Application of a weighted and cumulative average daily growth rate to an exponential decay model

To estimate the size of the novel coronavirus(COVID-19)outbreak in the early stage in Italy,this paper introduces the cumulated and weighted average daily growth rate(WR)to evaluate an epidemic curve.On the basis of an exponential decay model(EDM),we provide estimations of the WR in four-time intervals from February 27 to April 07,2020.By calibrating the parameters of the EDM to the reported data in Hubei Province of China,we also attempt to forecast the evolution of the outbreak.We compare the EDM applied to WR and the Gompertz model,which is based on exponential decay and is often used to estimate cumulative events.Specifically,we assess the performance of each model to short-term forecast of the epidemic,and to predict the final epidemic size.Based on the official counts for confirmed cases,the model applied to data from February 27 until the 17th of March estimate that the cumulative number of infected in Italy could reach 131,280(with a credibility interval 71,415-263,501)by April 25(credibility interval April 12 to May 3).With the data available until the 24st of March the peak date should be reached on May 3(April 23 to May 23)with 197,179 cumulative infections expected(130,033e315,269);with data available until the 31st of March the peak should be reached on May 4(April 25 to May 18)with 202,210 cumulative infections expected(155.235 e270,737);with data available until the 07st of April the peak should be reached on May 3(April 26 toMay 11)with 191,586(160,861-232,023)cumulative infections expected.Based on the average mean absolute percentage error(MAPE),cumulated infections forecasts provided by the EDM applied to WR performed better across all scenarios than the Gompertz model.An exponential decay model applied to the cumulated and weighted average daily growth rate appears to be useful in estimating the number of cases and peak of the COVID-19 outbreak in Italy and the model was more reliable in the exponential growth phase.

Preliminary Study on Feeding Habits of Anthocidaris crassispina

Abstract Employing experimental-ecological methods, the feeding and vitality of adult Anthocidaris crassispina were investigated. The results showed that A. cras- sispina exhibited an obvious preference on five different seaweeds, with the preference order of Betaphycus gelatinum 〉 Sargassum hemiphyllum 〉 Gelidium amansii 〉 Ulva lactuca 〉 Codium fragile. The daily feed intake of A. crassispina differed among U. lactuca, S. hemiphyllum and B. gelatinum. The feeding was affected by water temperature, seaweed species and body weight. The optimal vitality and feed intake were observed under 23 -27℃, which were inhibited under whether too higher or too lower temperature. Under the optimal temperature for feeding, the daily feed intake of adult A. crassispina assumed an exponentially-decreasing trend with increase of body weight.

On China’s Exchange Rate Flexibility and Stability: The More Flexible against the U.S. Dollar, the More Stable in Effective Terms

The Chinese authorities have often emphasized the importance of maintaining the renminbi＇s stable exchange rate without stating explicitly how this stability should be measured. This paper argues that the relevant concept for this stability should be in terms of the rnminbi＇s effective exchange rate, rather than its rate against any particular currency, such as the U. S. dollar. Under the current circumstances where key currencies＇ exchange rates fluctuate freely, if the authorities wish to maintain the stability of the renmnibi＇s effective exchange rate, they would want to let the renminbi＇s exchange rate fluctuate much more against the U. S. dollar than in the past because such fluctuations would greatly reduce the magnitude of the renminbi＇s fluctuations against other key currencies and thus its effective exchange rate. This point has been demonstrated by illustrative figures and by comparing the renminbi＇s hypothetical, greater exchange rate fluctuations with its actual fluctuations.