Migrant Semipalmated Sandpipers (Calidris pusilla) Have Over Four Decades Steadily Shifted Towards Safer Stopover Locations

Peregrine falcons (Falco peregrinus) have undergone a steady hemisphere-wide recovery since the ban on DDT in 1973, resulting in an ongoing increase in the level of danger posed for migrant birds, such as Arctic-breeding sandpipers. We anticipate that in response migrant semipalmated sandpipers (Calidris pusilla) have adjusted migratory behavior, including a shift in stopover site usage toward locations offering greater safety from falcon predation. We assessed semipalmated sandpiper stopover usage within the Atlantic Canada Shorebird Survey dataset. Based on 3,030 surveys (totalling ~32M birds) made during southward migration, 1974–2017, at 198 stopover locations, we assessed the spatial distribution of site usage in each year (with a “priority matching distribution” index, PMD) in relation to the size (intertidal area) and safety (proportion of a site\u27s intertidal area further than 150 m of the shoreline) of each location. The PMD index value is >1 when usage is concentrated at dangerous locations, 1.0 when usage matches location size, and <1 when usage is concentrated at safer locations. A large majority of migrants were found at the safest sites in all years, however our analysis of the PMD demonstrated that the fraction using safer sites increased over time. In 1974, 80% of birds were found at the safest 20% of the sites, while in 2017, this had increased to 97%. A sensitivity analysis shows that the shift was made specifically toward safer (and not just larger) sites. The shift as measured by a PMD index decline cannot be accounted for by possible biases inherent in the data set. We conclude that the data support the prediction that increasing predator danger has induced a shift by southbound migrant semipalmated sandpipers to safer sites

Kerr Noise Reduction and Squeezing

We introduce a model of squeezing and noise reduction in the Kerr effect that accounts for noise in all quadratures of the driving field. Consequently we show that Kerr squeezing is much more sensitive to driving noise than squeezing produced by second harmonic generation (SHG).We experimentally demonstrate this sensitivity using a nonlinear system that tunes between strong classical SHG and Kerr behaviours. Whilst the system experiences strong squeezing in the SHG limit, it experiences no squeezing in the Kerr limit, although it does experience strong classical noise reduction, or classical squeezing

Complete genome sequence of Alicyclobacillus acidocaldarius type strain (104-IA).

Alicyclobacillus acidocaldarius (Darland and Brock 1971) is the type species of the larger of the two genera in the bacillal family 'Alicyclobacillaceae'. A. acidocaldarius is a free-living and non-pathogenic organism, but may also be associated with food and fruit spoilage. Due to its acidophilic nature, several enzymes from this species have since long been subjected to detailed molecular and biochemical studies. Here we describe the features of this organism, together with the complete genome sequence and annotation. This is the first completed genome sequence of the family 'Alicyclobacillaceae'. The 3,205,686 bp long genome (chromosome and three plasmids) with its 3,153 protein-coding and 82 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project