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AbstractThe increasing rate of biological invasions resulting from human transport or human‐mediated changes to the environment has had devastating ecological and public health consequences. The kissing bug, Triatoma infestans, has dispersed through the Peruvian city of Arequipa. The biological invasion of this insect has resulted in a public health crisis, putting thousands of residents of this city at risk of infection by Trypanosoma cruzi and subsequent development of Chagas disease. Here, we show that populations of Tria. infestans in geographically distinct districts within and around this urban centre share a common recent evolutionary history although current gene flow is restricted even between proximal sites. The population structure among the Tria. infestans in different districts is not correlated with the geographical distance between districts. These data suggest that migration among the districts is mediated by factors beyond the short‐range migratory capabilities of Tria. infestans and that human movement has played a significant role in the structuring of the Tria. infestans population in the region. Rapid urbanization across southern South America will continue to create suitable environments for Tria. infestans, and knowledge of its urban dispersal patterns may play a fundamental role in mitigating human disease risk.

The complex processes involved with animal migration have long been a subject of biological interest, and broad-scale movement patterns of many marine turtle populations still remain unresolved. While it is widely accepted that once marine turtles reach sexual maturity they home to natal areas for nesting or reproduction, the role of philopatry to natal areas during other life stages has received less scrutiny, despite widespread evidence across the taxa. Here we report on genetic research that indicates that juvenile hawksbill turtles ( Eretmochelys imbricata ) in the eastern Pacific Ocean use foraging grounds in the region of their natal beaches, a pattern we term natal foraging philopatry. Our findings confirm that traditional views of natal homing solely for reproduction are incomplete and that many marine turtle species exhibit philopatry to natal areas to forage. Our results have important implications for life-history research and conservation of marine turtles and may extend to other wide-ranging marine vertebrates that demonstrate natal philopatry.

A new material (Alg–TSC), based on alginate (Alg) chemically modified with thiosemicarbazide (TSC), has been synthesized and tested as an effective biomaterial to remove Pb(II) and Cd(II) ions in aqueous solutions. The synthesis was carried out by controlling the following steps, i/partial oxidation process of alginate in NaIO to obtain AlgOx, ii/reacting of AlgOx, at 40–45 °C, with TSC in NaBH. Alg–TSC has been characterized by Field Emission Scanning Electron Microscopy (FESEM/EDS), Fourier Transform Infrared Spectroscopy (ATR-IR), solid state C NMR spectroscopy and Point of Zero Charge (pH) measuremenmts. In order to enhance the sorption process, the effect of contact time, sorbent dosage, initial concentration and reusability of the novel sorbent were investigated becoming the Alg–TSC a promising material capable of removing high concentrations of heavy metal ions such as Pb(II) (up to 950 mg/g at pH 3) and Cd(II) (up to 300 mg/g at pH 7) in aqueous solutions. Peer Reviewed

Author(s): Garcon, V; Karstensen, J; Palacz, A; Telszewski, M; Aparco Lara, T; Breitburg, D; Chavez, F; Coelho, P; Cornejo-D’Ottone, M; Santos, C; Fiedler, B; Gallo, ND; Gregoire, M; Gutierrez, D; Hernandez-Ayon, M; Isensee, K; Koslow, T; Levin, L; Marsac, F; Maske, H; Mbaye, BC; Montes, I; Naqvi, W; Pearlman, J; Pinto, E; Pitcher, G; Pizarro, O; Rose, K; Shenoy, D; Van der Plas, A; Vito, MR; Weng, K | Abstract: Multidisciplinary ocean observing activities provide critical ocean information to satisfy ever-changing socioeconomic needs and require coordinated implementation. The upper oxycline (transition between high and low oxygen waters) is fundamentally important for the ecosystem structure and can be a useful proxy for multiple observing objectives connected to eastern boundary systems (EBSs) that neighbor oxygen minimum zones (OMZs). The variability of the oxycline and its impact on the ecosystem (VOICE) initiative demonstrates how societal benefits drive the need for integration and optimization of biological, biogeochemical, and physical components of regional ocean observing related to EBS. In liaison with the Global Ocean Oxygen Network, VOICE creates a roadmap toward observation-model syntheses for a comprehensive understanding of selected oxycline-dependent objectives. Local to global effects, such as habitat compression or deoxygenation trends, prompt for comprehensive observing of the oxycline on various space and time scales, and for an increased awareness of its impact on ecosystem services. Building on the Framework for Ocean Observing (FOO), we present a first readiness level assessment for ocean observing of the oxycline in EBS. This was to determine current ocean observing design and future needs in EBS regions (e.g., the California Current System, the Equatorial Eastern Pacific off Ecuador, the Peru–Chile Current system, the Northern Benguela off Namibia, etc.) building on the FOO strategy. We choose regional champions to assess the ocean observing design elements proposed in the FOO, namely, requirement processes, coordination of observational elements, and data management and information products and the related best practices. The readiness level for the FOO elements was derived for each EBS through a similar and very general ad hoc questionnaire. Despite some weaknesses in the questionnaire design and its completion, an assessment was achievable. We found that fisheries and ecosystem management are a societal requirement for all regions, but maturity levels of observational elements and data management and information products differ substantially. Identification of relevant stakeholders, developing strategies for readiness level improvements, and building and sustaining infrastructure capacity to implement these strategies are fundamental milestones for the VOICE initiative over the next 2–5 years and beyond.

El objetivo del estudio fue evaluar el efecto del tipo de yema de huevo (codorniz-YC vs gallina-YG) sobre la calidad del semen de paco (Piaractus brachypomus) (volumen, color, concentración, motilidad, vitalidad y fertilidad) congelado. Se utilizaron 18 reproductores (15 machos y 3 hembras) cuya espermiación y ovulación, respectivamente, fue inducida con extracto de hipófisis de carpa. El semen fue colectado mediante masaje del abdomen del pez. El semen fresco fue evaluado y luego diluido con una solución crioprotetora que incluyó YC o YG. El semen diluido fue congelado y descongelado a los 30 días para la evaluación pos-descongelación y prueba de fertilidad. Se encontró una notoria disminución de los parámetros seminales por efecto de la congelación. La motilidad fue menor para la YC comparado a la YG (14.8 vs. 18.8%; p<0.05), mientras que la vitalidad (31 vs. 28.8%), tiempo de activación (1.4 vs. 1.3 min) y la fertilidad (18.4 vs. 20.4%) fueron similares entre grupos. En conclusión, la motilidad fue mejorada con la adición de yema de huevo de gallina, mientras que la vitalidad, tiempo de activación y fertilidad no fueron influenciados por el tipo de yema. The objective of the study was to evaluate the effect of the type of egg yolk (quail-YC vs hen-YG) on the quality of frozen paco (Piaractus brachypomus) semen (volume, colour, concentration, motility, vitality and fertility). Eighteen breeders (15 males and 3 females) were used, whose spermiation and ovulation, respectively, were induced with carp pituitary extract. Semen was collected by massaging the abdomen of the fish. Fresh semen was evaluated and then diluted with a cryoprotective solution that included YC or YG. Diluted semen was frozen and thawed at 30 days for post-thaw evaluation and fertility testing. A notable decrease in seminal parameters was found due to the effect of freezing. Motility was lower for YC compared to YG (14.8 vs. 18.8%; p<0.05), while vitality (31 vs. 28.8%), activation time (1.4 vs. 1.3 min) and fertility (18.4 vs. 20.4%) were similar between groups. In conclusion, the motility was improved with the addition of chicken egg yolk, while the vitality, activation time and fertility were not influenced by the type of yolk.

The impact of intraseasonal coastal-trapped waves on the nearshore Peru ecosystem is investigated using observations and a regional eddy-resolving physical-ecosystem coupled model. Model results show that intraseasonal variability over the period 2000-2006 represents about one fourth of the total surface chlorophyll variance and one third of the carbon export variance on the Peruvian shelf. Evidence is presented that subsurface nutrient and chlorophyll intraseasonal variability are mainly forced by the coastally trapped waves triggered by intraseasonal equatorial Kelvin waves reaching the South American coast, and propagate poleward along the Peru shore at a speed close to that of high order coastal trapped waves modes. The currents associated with the coastal waves induce an input of nutrients that triggers a subsequent phytoplankton bloom and carbon export. The impact of the local wind-forced intraseasonal variability on the ecosystem is of a similar order of magnitude to that remotely forced in the northern part of the Peru shelf on [50-90] day time scales and dominates over the entire shelf on [20-30] day time scales. International audience

Climate change is expected to affect marine mercury (Hg) biogeochemistry and biomagnification. Recent modeling work suggested that ocean warming increases methylmercury (MeHg) levels in fish. Here, we studied the influence of El Niño Southern Oscillations (ENSO) on Hg concentrations and stable isotopes in time series of seabird blood from the Peruvian upwelling and oxygen minimum zone. Between 2009 and 2016, La Niña (2011) and El Niño conditions (2015–2016) were accompanied by sea surface temperature anomalies up to 3 °C, oxycline depth change (20–100 m), and strong primary production gradients. Seabird Hg levels were stable and did not co-vary significantly with oceanographic parameters, nor with anchovy biomass, the primary dietary source to seabirds (90%). In contrast, seabird Δ$^{199}$Hg, proxy for marine photochemical MeHg breakdown, and δ$^{15}$N showed strong interannual variability (up to 0.8 and 3‰, respectively) and sharply decreased during El Niño. We suggest that lower Δ$^{199}$Hg during El Niño represents reduced MeHg photodegradation due to the deepening of the oxycline. This process was balanced by equally reduced Hg methylation due to reduced productivity, carbon export, and remineralization. The non-dependence of seabird MeHg levels on strong ENSO variability suggests that marine predator MeHg levels may not be as sensitive to climate change as is currently thought. Publisher: American Chemical Society International audience