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In migratory marine species, demographic estimates are often generated from capture-mark-recapture (CMR) studies conducted at terrestrial breeding sites. However, when logistical difficulties limit the geographic area of these surveys, demographic estimates are vulnerable to biases. We compared demographic rates generated from CMR data of nesting loggerhead turtles (Caretta caretta) collected between 2010 and 2017 at one focal site (Wassaw Island, Georgia, USA; 31.89° N, 80.97° W) with estimates generated from the same group of turtles but including all other nesting events from adjacent sites in Georgia, South Carolina, and North Carolina. We found that estimates of annual recruitment at the focal site were overestimated: each year, 29–45% putative first-time nesters at the focal beach had, in fact, nested on a different beach in a previous season. Estimates of clutch frequency and breeding frequency generated at the focal site were biased low and skewed towards values of one, while estimates for remigration interval were not significantly over- or underestimated. Additionally, estimates of annual and total population productivity in terms of clutches, eggs, and hatchlings were underestimated by more than half at the focal site. Our results show how weak fidelity to a focal nesting/tagging site can affect demographic estimates in marine turtle populations and highlight the need to reconsider estimates from other populations that might be vulnerable to similar biases. [ABSTRACT FROM AUTHOR]

Capture–mark–recapture (CMR) studies on marine turtle nesting beaches provide data on reproductive periodicity that inform population trends and models. Annual survival is estimated from observations of remigration, the return of females in subsequent nesting seasons. However, a significant proportion of tagged females are never encountered remigrating in many studies, presumably due to weak nest site fidelity (NSF). We employed a genetic CMR approach based on subpopulation-scale clutch sampling to conduct a 5-year evaluation of inter-seasonal recapture rates and NSF for Northern Recovery Unit loggerhead turtles (Caretta caretta). Of 1770 females genetically tagged from Georgia through Maryland in 2010, 1156 (65%) remigrated between 2011 and 2015. Inter-seasonal NSF, measured as shifts in median latitude nesting locations between years, was highly variable among individuals but strong overall (mean: 15.08 (± 44.61) km, median: 1.84 km). Among three focal beaches with nocturnal tagging projects, 69 of 173 females (40%) remigrated onsite whereas 115 (66%) were detected overall. Regional genetic sampling therefore yielded significantly higher inter-seasonal recapture rates, which may improve precision in future survival analyses. However, despite sampling ~ 1000 km with high annual detection probabilities (p* ≥ 0.94), 35% of 2010-females were not detected remigrating. Several non-exclusive hypotheses to explain these remaining "missing" remigrants should be considered: longer remigration intervals, imperfect detection within the study area, emigration to Florida, anthropogenic mortality, and natural mortality or senescence. This genetic tagging approach can be applied over large spatial scales where nesting densities permit, better characterizing inter-seasonal dispersal. [ABSTRACT FROM AUTHOR]

Population assessments conducted at reproductive sites of migratory species necessitate understanding the foraging-area origins of breeding individuals. Without this information, efforts to contextualize changes in breeding populations and develop effective management strategies are compromised. We used stable isotope analysis of tissue samples collected from loggerhead sea turtles (Caretta caretta) nesting at seven sites in the Northern Recovery Unit (NRU) of the eastern United States (North Carolina, South Carolina and Georgia) to assign females to three separate foraging areas in the Northwest Atlantic Ocean (NWA). We found that the majority of the females at NRU nesting sites (84.4%) use more northern foraging areas in the Mid-Atlantic Bight, while fewer females use more proximate foraging areas in the South Atlantic Bight (13.4%) and more southerly foraging areas in the Subtropical Northwest Atlantic (2.2%). We did not find significant latitudinal or temporal trends in the proportions of NRU females originating from different foraging areas. Combining these findings with previous data from stable isotope and satellite tracking studies across NWA nesting sites showed that variation in the proportion of adult loggerheads originating from different foraging areas is primarily related differences between recovery units: individuals in the NRU primarily use the Mid-Atlantic Bight foraging area, while individuals from the three Florida recovery units primarily use the Subtropical Northwest Atlantic and Eastern Gulf of Mexico foraging areas. Because each foraging area is associated with its own distinct ecological characteristics, environmental fluctuations and anthropogenic threats that affect the abundance and productivity of individuals at nesting sites, this information is critical for accurately evaluating population trends and developing effective region-specific management strategies. [ABSTRACT FROM AUTHOR]

Summary: Major complications of laryngoscopy and tracheal intubation are rare. However, mucosal trauma during airway management can lead to the introduction of oropharyngeal bacterial flora into the deep neck spaces, with the potential for fatal complications. This report describes the development of a paratracheal abscess in a healthy 62‐year‐old man following an outpatient herniorrhaphy. The patient was treated with intravenous antibiotics and underwent ultrasound‐guided needle aspiration of the abscess. He was later re‐admitted to the hospital with re‐accumulation of the abscess, which was successfully treated by open surgical drainage. Though deep neck space infection following laryngoscopy is more common in patients with significant comorbidities and when tracheal intubation has been difficult, this case highlights the need for careful airway management in all patients. [ABSTRACT FROM AUTHOR]

Green turtle nesting has been recorded in North Carolina, since 1980, but how these nesting females fit into the broader regional context genetically has not been determined. Genetic tagging through microsatellite genotyping of clutches laid in northern South Carolina, North Carolina, and Delaware from 2010 through 2014 identified at least 52 individual nesting females. The mitochondrial control region haplotype frequencies of these individuals were significantly different from all northern Greater Caribbean suhpopulations, including those in Florida, suggesting that these northern US females represent an incipient subpopulation that warrants distinct management unit status. [ABSTRACT FROM AUTHOR]

mRNA in eukaryotic cells is packaged into highly compacted ribonucleoprotein particles (mRNPs) in the nucleus and exported to the cytoplasm for translation. mRNP packaging and export require the evolutionarily conserved transcription-export (TREX) complex. TREX facilitates loading of various RNA-binding proteins on mRNA through the action of its DDX39B subunit. SARNP (Tho1 [transcriptional defect of Hpr1 by overexpression 1] in yeast) is shown to interact with DDX39B and affect mRNA export. The molecular mechanism of how SARNP recognizes DDX39B and functions in mRNP assembly is unclear. Here, we determine the crystal structure of a Tho1/DDX39B/RNA complex, revealing a multivalent interaction mediated by tandem DDX39B interacting motifs in SARNP/Tho1. The high-order complex of SARNP and DDX39B is evolutionarily conserved, and human SARNP can engage with five DDX39B molecules. RNA sequencing (RNA-seq) from SARNP knockdown cells shows the most affected RNAs in export are GC rich. Our work suggests the role of the high-order SARNP/DDX39B/RNA complex in mRNP assembly and export. [Display omitted] • Crystal structure of a ScTho1SARNP/DDX39B/RNA complex • SARNP binds DDX39B through multivalent interaction with tandem DDX39B interacting motifs • mRNAs that are dependent on SARNP for nuclear export show high GC content • SARNP, ALYREF, and DDX39B could coordinate to facilitate mRNP assembly Xie et al. describe a multivalent interaction between the mRNA export factors SARNP and DDX39B. They present the crystal structure of a ScTho1SARNP/DDX39B/RNA complex and show that SARNP features tandem DDX39B interacting motifs. This study highlights the role of DDX39B in regulating mRNP dynamics and assembly through high-order structures. [ABSTRACT FROM AUTHOR]

Nest counts are often used as indices for nesting female abundance in marine turtle monitoring, but accurately interpreting nest count trends requires context on the scale of demographic connectivity and estimates of reproductive parameters. Weak nest site fidelity (NSF) relative to the scale of tagging effort may bias parameter estimates. The reproductive ecology of Northern Recovery Unit (NRU) loggerhead turtles ( Caretta caretta) was assessed through subpopulation-scale genetic capture-recapture via clutch sampling from approximately 1000 km of coastline from Georgia to Maryland, USA (30.75-38.06°N and 75.24-81.45°W). Of 20,682 clutches recorded from 2010 to 2012, 20,222 sampled clutches were assigned to 5684 unique females through microsatellite genotyping. Approximately 73% of females detected laying multiple clutches deposited them within a 20-km span, suggesting the possibility of demographic structuring across NRU rookeries that warrants further investigation. Estimated clutch frequencies (ECF) generated from open robust design modeling were 4.28 (4.02-4.54) in 2010, 4.63 (4.45-4.80) in 2011, and 4.57 (4.28-4.77) in 2012, and were significantly higher than observed clutch frequencies. ECF generated from single-island data were biased low by 23-50% relative to those from regional genetic tagging. Among females that nested at least once on a physical tagging beach, 54% also nested elsewhere, with 81% of these 'permanently' emigrating during the nesting season. This pattern of relatively strong NSF, but distributed across multiple nearby islands, confounded modeling of detection in single-island datasets and highlights the need for regional coverage for generating robust estimates of demographic parameters for marine turtles. [ABSTRACT FROM AUTHOR]