Leveraging satellite technology to create true shark sanctuaries

Shark sanctuaries are an ambitious attempt to protect huge areas of ocean space to curtail overfishing of sharks. If shark sanctuaries are to succeed, effective surveillance and enforcement is urgently needed. We use a case study with a high level of illegal shark fishing within a shark sanctuary to help motivate three actionable opportunities to create truly effective shark sanctuaries by leveraging satellite technology: (1) require vessel tracking systems; (2) partner with international research organizations; and (3) ban vessels previously associated with illegal fishing from shark sanctuaries. Sustaining the level of fishing mortality observed in our case study would lead even a healthy shark population to collapse to <10% of its unfished state in fewer than five years. We outline implementations pathways and provide a roadmap to pair new and emerging satellite technologies with existing international agreements to offer new hope for shark conservation successes globally

An evaluation of the effectiveness of the crew resource management programme in naval aviation

The US Navy’s Crew Resource Management (CRM) training programme has not been evaluated within the last decade. Reactions were evaluated by analysing 51,570 responses to an item pertaining to CRM that is part of a safety climate survey. A total of 172 responses were obtained on a knowledge test. The attitudes of 553 naval aviators were assessed using an attitudes questionnaire. The CRM mishap rate from 1997 until 2007 was evaluated. It was found that naval aviators appear to think than CRM training is useful, are generally knowledgeable of, and display positive attitudes towards, the concepts addressed in the training. However, there is a lack of evidence to support the view that CRM training is having an effect on the mishap rate. As the next generation of highly automated aircraft becomes part of naval aviation, there is a need to ensure that CRM training evolves to meet this new challenge

Gut microbiota in HIV-pneumonia patients is related to peripheral CD4 counts, lung microbiota, and in vitro macrophage dysfunction.

Pneumonia is common and frequently fatal in HIV-infected patients, due to rampant, systemic inflammation and failure to control microbial infection. While airway microbiota composition is related to local inflammatory response, gut microbiota has been shown to correlate with the degree of peripheral immune activation (IL6 and IP10 expression) in HIV-infected patients. We thus hypothesized that both airway and gut microbiota are perturbed in HIV-infected pneumonia patients, that the gut microbiota is related to peripheral CD4+ cell counts, and that its associated products differentially program immune cell populations necessary for controlling microbial infection in CD4-high and CD4-low patients. To assess these relationships, paired bronchoalveolar lavage and stool microbiota (bacterial and fungal) from a large cohort of Ugandan, HIV-infected patients with pneumonia were examined, and in vitro tests of the effect of gut microbiome products on macrophage effector phenotypes performed. While lower airway microbiota stratified into three compositionally distinct microbiota as previously described, these were not related to peripheral CD4 cell count. In contrast, variation in gut microbiota composition significantly related to CD4 cell count, lung microbiota composition, and patient mortality. Compared with patients with high CD4+ cell counts, those with low counts possessed more compositionally similar airway and gut microbiota, evidence of microbial translocation, and their associated gut microbiome products reduced macrophage activation and IL-10 expression and increased IL-1β expression in vitro. These findings suggest that the gut microbiome is related to CD4 status and plays a key role in modulating macrophage function, critical to microbial control in HIV-infected patients with pneumonia

Sprinkler Irrigation as an Energy and Water Saving Approach to Rice Production and Management of Riceland Pests

Rice is currently produced on approximately 400,000 acres in the Texas Coastal Prairie. This rice consumes 1.8 million acre-feet of water a year or 13 percent of Texas' renewable water resources. The Texas Coastal Prairie is a delicate ecosystem providing winter homes for many birds and water fowl and breeding grounds for marine life in the marshes of the Gulf Coast. The Texas Coastal Prairie has been experiencing rapid population and industrial growth. These areas of growth are placing increased demands on the water of the area. Continued rice production will require water conservation practices. This research evaluated the potential water conservation for sprinkler irrigation in rice production. The research evaluated the potential production of prominent commercial cultivars under various levels of moisture stress, the adaptability of 10 major soil series to the utilization of sprinkler irrigation, and the use of adjuvants to increase the infiltration on one low infiltration soil. Some cultivars did exhibit resistance defined as sustained production under reduced water supply. However, these cultivars were not the most productive. The cultivars which are the highest yielding under flood irrigation were also the highest yielding under sprinkler irrigation. The medium grains appear to be the most adaptive. However, some long grains did show potential. Adjuvants tested did increase the water infiltration into the Nada soil. Yield levels within 15 percent of those from flood irrigations were achieved. However, the high levels of adjuvants used were phytotoxic to the rice. Lower rates or other adjuvants might be better adapted to use on rice. Soil water infiltration as determined by rainfall simulator did reveal differences in infiltration rates of the soils tested. The clay soils had the highest infiltration rate at saturation. The fine sandy loam soils developed a crust after initial applications which reduced later infiltration rates significantly. All soils could be irrigated but some of the soils such as the Nada fine sandy loam had a saturated infiltration of less than 0.65 cm per hour which could be prohibitive to a commercial rice production system

Herbivores at the Highest Risk of Extinction Among Mammals, Birds, and Reptiles

As a result of their extensive home ranges and slow population growth rates, predators have often been perceived to suffer higher risks of extinction than other trophic groups. Our study challenges this extinction-risk paradigm by quantitatively comparing patterns of extinction risk across different trophic groups of mammals, birds, and reptiles. We found that trophic level and body size were significant factors that influenced extinction risk in all taxa. At multiple spatial and temporal scales, herbivores, especially herbivorous reptiles and large-bodied herbivores, consistently have the highest proportions of threatened species. This observed elevated extinction risk for herbivores is ecologically consequential, given the important roles that herbivores are known to play in controlling ecosystem function

Growth and life history variability of the grey reef shark (Carcharhinus amblyrhynchos) across its range

For broadly distributed, often overexploited species such as elasmobranchs (sharks and rays), conservation management would benefit from understanding how life history traits change in response to local environmental and ecological factors. However, fishing obfuscates this objective by causing complex and often mixed effects on the life histories of target species. Disentangling the many drivers of life history variability requires knowledge of elasmobranch populations in the absence of fishing, which is rarely available. Here, we describe the growth, maximum size, sex ratios, size at maturity, and offer a direct estimate of survival of an unfished population of grey reef sharks (Carcharhinus amblyrhynchos) using data from an eight year tag-recapture study. We then synthesized published information on the life history of C. amblyrhynchos from across its geographic range, and for the first time, we attempted to disentangle the contribution of fishing from geographic variation in an elasmobranch species. For Palmyra’s unfished C. amblyrhynchos population, the von Bertalanffy growth function (VBGF) growth coefficient k was 0.05 and asymptotic length L∞ was 163.3 cm total length (TL). Maximum size was 175.5 cm TL from a female shark, length at maturity was estimated at 116.7–123.2 cm TL for male sharks, maximum lifespan estimated from VBGF parameters was 18.1 years for both sexes combined, and annual survival was 0.74 year-1. Consistent with findings from studies on other elasmobranch species, we found significant intraspecific variability in reported life history traits of C. amblyrhynchos. However, contrary to what others have reported, we did not find consistent patterns in life history variability as a function of biogeography or fishing. Ultimately, the substantial, but not yet predictable variability in life history traits observed for C. amblyrhynchos across its geographic range suggests that regional management may be necessary to set sustainable harvest targets and to recover this and other shark species globally

Evening choruses in the Perth Canyon and their potential link with Myctophidae fishes

An evening chorus centered at near 2.2 kHz was detected across the years 2000 to 2014 from seabed receivers in 430-490 m depth overlooking the Perth Canyon, Western Australia. The chorus reached a maximum level typically 2.1 h post-sunset and normally ran for 2.1 h (between 3 dB down points). It was present at lower levels across most of the hours of darkness. Maximum chorus spectrum levels were 74-76 dB re 1 µPa2/Hz in the 2 kHz 1/3 octave band, averaging 6-12 dB and up to 30 dB greater than pre-sunset levels. The chorus displayed highest levels over April to August each year with up to 10 dB differences between seasons. The spatial extent of the chorus was not determined but exceeded the sampling range of 13-15 km offshore from the 300 m depth contour and 33 km along the 300 m depth contour. The chorus comprised short damped pulses. The most likely chorus source is considered to be fishes of the family Myctophidae foraging in the water column. The large chorus spatial extent and its apparent correlation with regions of high productivity suggest it may act as an acoustic beacon to marine fauna indicating regions of high biomass

Resetting predator baselines in coral reef ecosystems

What did coral reef ecosystems look like before human impacts became pervasive? Early efforts to reconstruct baselines resulted in the controversial suggestion that pristine coral reefs have inverted trophic pyramids, with disproportionally large top predator biomass. The validity of the coral reef inverted trophic pyramid has been questioned, but until now, was not resolved empirically. We use data from an eight-year tag-recapture program with spatially explicit, capture-recapture models to re-examine the population size and density of a key top predator at Palmyra atoll, the same location that inspired the idea of inverted trophic biomass pyramids in coral reef ecosystems. Given that animal movement is suspected to have significantly biased early biomass estimates of highly mobile top predators, we focused our reassessment on the most mobile and most abundant predator at Palmyra, the grey reef shark (Carcharhinus amblyrhynchos). We estimated a density of 21.3 (95% CI 17.8, 24.7) grey reef sharks/km2, which is an order of magnitude lower than the estimates that suggested an inverted trophic pyramid. Our results indicate that the trophic structure of an unexploited reef fish community is not inverted, and that even healthy top predator populations may be considerably smaller, and more precarious, than previously thought

Population Genetic Structure Of A Coral Reef Ecosystem Apex Predator, The Gray Reef Shark (Carcharhinus Amblyrhynchos)

Sharks play a major functional role as apex predators in coral reef ecosystems, raising concerns that their ongoing overexploitation will compromise the integrity and sustainability of reefs. The gray reef shark (Carcharhinus amblyrhynchos) is a strongly coral reef associated species whose populations are known to have declined substantially in some regions. There is no information on population structure in this species to aid in their management and conservation. We are assessing genetic structure in this species by using entire mitochondrial control region sequences and 15 nuclear microsatellite loci as markers. 93 gray reef shark samples were obtained from across the species’ Indo-Pacific distribution (eastern Indian Ocean [Madagascar/Seychelles], Central Pacific [Hawaii], Southwestern Pacific (eastern Australia, Palmyra, Palau, Cocos (Keeling) Islands]). Mitochondrial (AMOVA) and microsatellite (STRUCTURE) data concordantly identify the Hawaii population as a distinct genetic group relative to other sampling locations. The microsatellite data further identify 3 distinct overall gray reef shark groups (eastern Indian Ocean, Central Pacific, and Southwestern Pacific). Our current analyses do not show any evidence of population structure among islands of the Southwestern Pacific, although this question is being further addressed with additional samples from more locations. These results show strong genetic differentiation exists in gray reef shark populations separated by expanses of open ocean, and suggest proper management of this declining species will have to occur at the very least on a regional geographic scale