Habitat dimensions of calanoid copepods in the western Gulf of Mexico

The vertical distributions of 49 species (53 taxa) of calanoid copepods were determined in cyclonic and anticyclonic hydrographic features in the western Gulf of Mexico for three seasons of the year. The relative intensities of the features varied among seasons, while within seasons the physical structure between features was different. Since the same copepod species were present in both features for all seasons sampled, the contrasting hydrography provided a natural experiment in which to study the mechanisms, biological or physical, acting to influence species vertical distribution patterns. Hierarchial classification analysis revealed that groups of samples characterized by relatively homogeneous biotic characteristics were related more to depth of the sample than to the season or location (hydrographic feature) in which the sample was taken. Species groups defined by the classification analysis also tended to occupy different depth zones, but the species groups overlapped strongly in the vertical dimension. Significant species structure was found as well, with stability of the rank order of species abundances. Both species and vertical structure persisted over time and were resistant to nonseasonal hydrographic variability. A weighted version of multiple discriminant analysis was used to relate the species patterns to the environmental patterns. The most important extrinsic variable correlated with where species were likely to occur was depth, although the depth distributions of chlorophyll and nitrate cannot be ignored. In the absence of corresponding abiotic patterns, biotic factors are suggested as the dominant causative agents of copepod vertical distribution patterns. It is proposed that on a broad scale the observed constancy of copepod species and vertical spatial structure is related to the “nutrient-limited” and “light-limited” physiological regimens documented for oceanic phytoplankton species

Occurrence of Corbicula manilensis Phillipi in the Lower Minnesota River

On March 2, 1978, several empty shells of the fresh water clam, Corbicula manilensis Phillipi, were collected in the Minnesota River near the Blackdog electric generating plant in Burnsville, Minnesota. Since this Asiatic species was first observed in America in 1935, it has spread into all major river systems of North America. Its northernly extension in the Mississippi River system was, however, thought to end in northeast Iowa and to exclude Minnesota. Occurrence of this species is a potential liability because it often exerts a disruptive influence in the community that it invades

Toward a descriptive model of galactic cosmic rays in the heliosphere

Researchers review the elements that enter into phenomenological models of the composition, energy spectra, and the spatial and temporal variations of galactic cosmic rays, including the so-called anomalous cosmic ray component. Starting from an existing model, designed to describe the behavior of cosmic rays in the near-Earth environment, researchers suggest possible updates and improvements to this model, and then propose a quantitative approach for extending such a model into other regions of the heliosphere

POTENTIAL BIRD REPELLENTS TO REDUCE BIRD DAMAGE TO LETTUCE SEED AND SEEDLINGS

The authors evaluated the effectiveness of ReJeX-iT® AG-145, Mesurol®, activated charcoal, lime, and fipronil to reduce homed lark damage to lettuce seeds and seedlings. In Experiment 1, homed larks consumed significantly more feed mixture (50:50 grains and lettuce seed) than untreated clay-coated lettuce seed in a three-day choice-test. In Experiment 2, where clay-coated lettuce seed was treated with ReJeX-iT® AG- 145, Mesurol®, activated charcoal, or lime, there was no significant difference in consumption of untreated clay-coated lettuce seed and treated clay-coated lettuce seed. Homed larks consumed insignificant amounts of all seed treatments including untreated coated lettuce seed. In this experiment homed larks lost an average of 28 % of their body weight over the three-day test period. It was concluded that the clay seed coating alone reduced damage significantly. In the aviary test, flats of sprouting lettuce seedlings were sprayed with Mesurol® (4 kg/ha), ReJeX-iT® AG-145 (64 kg/ha), lime (32 kg/ha), activated charcoal (32 kg/ha), and fipronil(4 kg/ha). Mesurol®, ReJeX-iT® AG-145, and lime significantly reduced consumption of lettuce seedlings over a four-day test period. Even though lime significantly reduced consumption, homed larks still consumed over 50% of the available lettuce seedlings. Field evaluations are warranted with Mesurol® and ReJeX-iT® AG-145

GRB 071028B, a burst behind large amounts of dust in an unabsorbed galaxy

We report on the discovery and properties of the fading afterglow and underlying host galaxy of GRB 071028B, thereby facilitating a detailed comparison between these two. Observations were performed with the Gamma-ray Burst Optical and Near-infrared Detector at the 2.2 m telescope on the La Silla Paranal Observatory in Chile. We conducted five observations from 1.9 d to 227.2 d after the trigger and obtained deep images in the g'r'i'z' and JHKs bands. Based on accurate seven-channel photometry covering the optical to near-infrared wavelength range, we derive a photometric redshift of z = 0.94 +0.05 -0.10 for the unabsorbed host galaxy of GRB 071028B. In contrast, we show that the afterglow with an intrinsic extinction of AV(SB) = (0.70 +/- 0.11) mag is moderately absorbed and requires a relatively flat extinction curve. According to the reported Swift/BAT observations, the energetics yield an isotropic energy release of E(gamma,iso.,rest) = (1.4 +2.4 -0.7) x 10^51 erg.Comment: 8 pages, 5 figures, accepted for publication in A&

Translocating Common Nighthawks at McConnell Air Force Base, Kansas to Reduce Aircraft Strikes

McConnell Air Force Base (MAFB) experiences a unique bird/aircraft hazard problem with migrating common nighthawks (Chordeiles minor) from August-October. Nighthawks are the most commonly struck species at MAFB, representing about 38% of total reported bird/aircraft strikes and 82% of the strikes from August-October. Factors that contribute to an over abundance of nighthawks on MAFB are: abundant foraging opportunities in close proximity to the airfield, available roosting habitat for nighthawks on and around the airfield, the lack of a Bird Aircraft Strike Hazard program to address nighthawks, and the location of MAFB on a nighthawk migration route. Approaches for managing nighthawks on and around airfields are limited because of their nocturnal behavior, logistics, and an incomplete understanding of nighthawk behavior. At MAFB, we determined the number of nighthawks using the airfield; their foraging, loafing and roosting areas; and their feeding habits. Based on this information, we developed a management strategy to reduce the nighthawk hazard to aircraft. From August-October in 1999 and 2000, we recorded 540 and 920 observations, respectively, of nighthawks using the airfield. The number of individuals increased rapidly during August and September, reaching a peak between 9-14 September in 1999 and 27-30 September in 2000. During one 2-hour survey period each in 1999 and 2000, 37 and 59 nighthawks, respectively, were flushed from the airfield. Most nighthawk foraging activity at the airfield occurred between 1800-2200. Nighthawks started roosting on the airfield about 1800 with a peak between 2200-0200. Thirty-seven nighthawks collected during the study period consumed a variety of insects, consisting mostly of corn earworm moths (Noctuidae—47% of stomach contents) and beetles (Scarabaeidae). Insect sweeps of the airfield indicated a low density of these species of insects, suggesting that most nighthawks foraging activity occurred away from the airfield. Management of nighthawks on MAFB has been difficult because commonly used hazing techniques seem to be ineffective. Furthermore, nighthawks have a behavior of returning to the same roosting location after being flushed which can present an even greater risk to aircraft. We developed and evaluated a unique live-capture technique for nighthawks using the airfield for the purpose of evaluating nighthawk relocation. During 1999 and 2000, 215 nighthawks were captured and relocated to sites 44 km north and 88 km south from MAFB. Only one nighthawk returned to MAFB after being relocated 44 km north. The nighthawk returned after 11 days to within 100 m of its capture location. Relocation of nighthawks from MAFB in 1999 and 2000 reduced nighthawk/aircraft strikes from 9 in 1998 when no relocation was conducted to 0 in 1999 and 3 in 2000

Local variations in spatial synchrony of influenza epidemics

Background: Understanding the mechanism of influenza spread across multiple geographic scales is not complete. While the mechanism of dissemination across regions and states of the United States has been described, understanding the determinants of dissemination between counties has not been elucidated. The paucity of high resolution spatial-temporal influenza incidence data to evaluate disease structure is often not available. Methodology and Findings: We report on the underlying relationship between the spread of influenza and human movement between counties of one state. Significant synchrony in the timing of epidemics exists across the entire state and decay with distance (regional correlation = 62%). Synchrony as a function of population size display evidence of hierarchical spread with more synchronized epidemics occurring among the most populated counties. A gravity model describing movement between two populations is a stronger predictor of influenza spread than adult movement to and from workplaces suggesting that non-routine and leisure travel drive local epidemics. Conclusions: These findings highlight the complex nature of influenza spread across multiple geographic scales. © 2012 Stark et al

Targeted ocean sampling guidance for tropical cyclones

This paper is not subject to U.S. copyright. The definitive version was published in Journal of Geophysical Research: Oceans 122 (2017): 3505–3518, doi:10.1002/2017JC012727.A 3-D variational ocean data assimilation adjoint approach is used to examine the impact of ocean observations on coupled tropical cyclone (TC) model forecast error for three recent hurricanes: Isaac (2012), Hilda (2015), and Matthew (2016). In addition, this methodology is applied to develop an innovative ocean observation targeting tool validated using TC model simulations that assimilate ocean temperature observed by Airborne eXpendable Bathy Thermographs and Air-Launched Autonomous Micro-Observer floats. Comparison between the simulated targeted and real observation data assimilation impacts reveals a positive maximum mean linear correlation of 0.53 at 400–500 m, which implies some skill in the targeting application. Targeted ocean observation regions from these three hurricanes, however, show that the largest positive impacts in reducing the TC model forecast errors are sensitive to the initial prestorm ocean conditions such as the location and magnitude of preexisting ocean eddies, storm-induced ocean cold wake, and model track errors.ONR Grant Numbers: N0001416WX01949, N0001416WX01384, N0001416WX01262; NOAA Grant Number: NA13OAR483023

MANAGING COMMON NIGHTHAWKS AT MCCONNELL AIR FORCE BASE, KANSAS, TO REDUCE AIRCRAFT STRIKES

McConnell Air Force Base (AFB) experiences a unique bird/aircraft hazard problem with migrating common nighthawks from August to October. Nighthawks are the most commonly struck species at McConnell AFB, representing about 38% of reported bird/aircraft strikes. During August and September, nighthawks represented 82% of the bird strikes found on the airfield. Approaches for managing nighthawks on and around airfields are limited because of the night environment, logistics and an incomplete understanding of nighthawk behavior. We determined the number of nighthawks using McConnell AFB and associated foraging, loafing and roosting areas, analyzed their food habits, and developed a translocation management strategy to reduce hazards to aircraft. During 1998, 1999 and 2000, we observed 600, 540 and 920 nighthawks, respectively, on the airfield. The greatest activity on the airfield occurred from September 27-30 in 1998, September 9- 14 in 1999, and September 6-8 in 2000. The peak number of nighthawks observed using the airfield during these periods was 142, 90 and 118, respectively. Nighthawks foraged around the airfield mainly between 1800 and 2200 and usually roosted on the airfield about 1800 with a peak between 2200 and 0200. During one 2-hour survey period in 1999 and 2000, 37 and 59 nighthawks, respectively, were flushed from the airfield. Thirty-seven nighthawks collected during the study consumed mostly corn earworm moths (Noctuidae) and beetles (Scarabaeidae). Management of nighthawks on McConnell AFB has been difficult because commonly used hazing techniques seem to be ineffective; these birds usually return to the same roosting location after being flushed, which can present an even greater risk to aircraft. We developed and evaluated a unique technique for capturing and translocating nighthawks from the airfield. Only 1 of 214 nighthawks translocated 88 km from McConnell AFB returned. Nighthawk/aircraft strikes at McConnell AFB declined from 9 in 1998, when no translocation was conducted, to 0 in 1999 and 3 in 2000