Characterization of microsatellite loci for a threatened species, the King Rail, Rallus elegans, using a next-generation sequencing protocol

The King Rail Rallus elegans (Audubon) has experienced population declines of 4.6 % per year on average since the 1960s. Wetland loss, most severely affecting inland marshes, has significantly reduced this species\u27 distribution to the coastal margins of its historic range. Polymorphic microsatellite markers were generated by 454 pyrosequencing of genomic DNA from King Rails, and Clapper Rails R. longirostris from Louisiana after AFLP enrichment and barcoding of restriction fragment cut sites across individuals. Of 1,419 microsatellite-containing sequences, 20 hypervariable microsatellite loci with up to 20 different alleles were identified at the alignment stage. We characterized nine loci, tested variability in 45 Atlantic coast King Rail samples, and detected 4-19 alleles per locus. Cross-species amplification revealed variability in the Virginia Rail, R. limicola, and Sora, Porzana carolina. These loci will be useful for studying secretive marsh rails, many of which are threatened or endangered. © 2013 Springer Science+Business Media Dordrecht

LSST: from Science Drivers to Reference Design and Anticipated Data Products

(Abridged) We describe here the most ambitious survey currently planned in the optical, the Large Synoptic Survey Telescope (LSST). A vast array of science will be enabled by a single wide-deep-fast sky survey, and LSST will have unique survey capability in the faint time domain. The LSST design is driven by four main science themes: probing dark energy and dark matter, taking an inventory of the Solar System, exploring the transient optical sky, and mapping the Milky Way. LSST will be a wide-field ground-based system sited at Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m effective) primary mirror, a 9.6 deg$^2$ field of view, and a 3.2 Gigapixel camera. The standard observing sequence will consist of pairs of 15-second exposures in a given field, with two such visits in each pointing in a given night. With these repeats, the LSST system is capable of imaging about 10,000 square degrees of sky in a single filter in three nights. The typical 5$\sigma$ point-source depth in a single visit in $r$ will be $\sim 24.5$ (AB). The project is in the construction phase and will begin regular survey operations by 2022. The survey area will be contained within 30,000 deg$^2$ with $\delta<+34.5^\circ$, and will be imaged multiple times in six bands, $ugrizy$, covering the wavelength range 320--1050 nm. About 90\% of the observing time will be devoted to a deep-wide-fast survey mode which will uniformly observe a 18,000 deg$^2$ region about 800 times (summed over all six bands) during the anticipated 10 years of operations, and yield a coadded map to $r\sim27.5$. The remaining 10\% of the observing time will be allocated to projects such as a Very Deep and Fast time domain survey. The goal is to make LSST data products, including a relational database of about 32 trillion observations of 40 billion objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures available from https://www.lsst.org/overvie