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In the tropics, limestone caves in karstic areas are known for their unique biodiversity. However, many caves remain unstudied and little is known about underlying gradients that determine diversity and biomass in aquatic microhabitats. Here, we sampled zooplankton and benthos in a set of 12 aquatic caves, locally called closed cenotes in Yucatán, Mexico. Our aim was to explain diversity patterns and differences in biomass with particular attention for correlations between bat colony characteristics and other biota. Compared with caves that support photosynthesis, diversity was low with an average of four planktonic and two benthic species in these dark caves. Undetectable phosphorus concentrations in the water suggest this nutrient is limiting. Several associations hint at a potential link between bat abundance and functional guild composition, water quality and aquatic biota. As such, more bats were linked to higher nitrate concentrations. Yet this was not translated to higher invertebrate biomass, probably since phosphorus is limiting. Overall, the trends found in this survey suggest that bats could be important as fertilizers of the caves although mechanistic links that mediate the flux of nutrients need to be confirmed experimentally.

Bat acoustic libraries are important tools that assemble echolocation calls to allow the comparison and discrimination to confirm species identifications. The Sonozotz project represents the first nation‐wide library of bat echolocation calls for a megadiverse country. It was assembled following a standardized recording protocol that aimed to cover different recording habitats, recording techniques, and call variation inherent to individuals. The Sonozotz project included 69 species of echolocating bats, a high species richness that represents 50% of bat species found in the country. We include recommendations on how the database can be used and how the sampling methods can be potentially replicated in countries with similar environmental and geographic conditions. To our knowledge, this represents the most exhaustive effort to date to document and compile the diversity of bat echolocation calls for a megadiverse country. This database will be useful to address a range of ecological questions including the effects of anthropogenic activities on bat communities through the analysis of bat sound., The Sonozotz project represents the first nation‐wide library of bat echolocation calls for a megadiverse country.

This study longitudinally investigated the association between Triatoma dimidiata infestation, triatomine infection with Trypanosoma cruzi and household/backyard environmental characteristics in 101 homesteads in Molas and Yucatan, Mexico, between November 2009 (rainy season) and May 2010 (dry season). Logistic regression models tested the associations between insect infestation/infection and potential household-level risk factors. A total of 200 T. dimidiata were collected from 35.6% of the homesteads, mostly (73%) from the peridomicile. Of all the insects collected, 48% were infected with T. cruzi. Infected insects were collected in 31.6% of the homesteads (54.1% and 45.9% intra- and peridomiciliary, respectively). Approximately 30% of all triatomines collected were found in chicken coops. The presence of a chicken coop in the backyard of a homestead was significantly associated with both the odds of finding T. dimidiata (OR = 4.10, CI 95% = 1.61-10.43, p = 0.003) and the presence of triatomines infected with T. cruzi (OR = 3.37, CI 95% = 1.36-8.33, p = 0.006). The results of this study emphasize the relevance of chicken coops as a putative source of T. dimidiata populations and a potential risk for T. cruzi transmission. Investigamos longitudinalmente la asociación entre la infestación por Triatoma dimidiata, su infección con Trypanosoma cruzi y las características ambientales de los domicilios/peridomicilios en 101 viviendas de Molas, Yucatán, México entre Noviembre de 2009 (temporada lluviosa) y Mayo de 2010 (temporada seca). Mediante modelos de regresión logística se probaron asociaciones entre la infestación/infección de T. dimidiata y factores de riesgo potenciales a nivel de las viviendas. Se colectó un total de 200 individuos de T. dimidiata en el 35.6% de las viviendas, mayormente del peridomicilio (73%). De todos los triatominos colectados el 48% se encontraron infectados con T. cruzi. Los triatomas infectados fueron colectados en el 31.6% de las viviendas (54.1% y 45.9% en intra y peridomicilio respectivamente). Aproximadamente el 30% de todos los triatominos colectados, fueron encontrados en gallineros. La presencia de un gallinero en el peridomicilio de una vivienda se asoció significativamante tanto con las posibilidades de encontrar T. dimidiata (OR = 4.10, CI 95% = 1.61-10.43, p = 0.003) como con la presencia de triatominos infectados con T. cruzi (OR = 3.37, CI 95% = 1.36-8.33, p = 0.006). Los resultados de este estudio enfatizan la relevancia de los gallineros como fuente putativa de poblaciones de T. dimidiata y como una fuente potencial de riesgo de transmisión de T. cruzi.

Background Dengue, recognized by the WHO as the most important mosquito-borne viral disease in the world, is a growing problem. Currently, the only effective way of preventing dengue is vector control. Standard methods have shown limited effect, and there have been calls to develop new integrated vector management approaches. One novel tool, protecting houses with long lasting insecticidal screens on doors and windows, is being trialled in a cluster randomised controlled trial by a joint UADY/WHO TDR/IDRC study in various districts of Acapulco, Mexico, with exceptionally high levels of crime and insecurity. This study investigated the community’s perspectives of long lasting insecticidal screens on doors and windows in homes and in schools, in order to ascertain their acceptability, to identify challenges to further implementation and opportunities for future improvements. Methods This was a sequential mixed-methods study. The quantitative arm contained a satisfaction survey administered to 288 houses that had received the intervention examining their perspectives of both the intervention and dengue prevention in general. The qualitative arm consisted of Focus Group Discussions (FGDs) with those who had accepted the intervention and key informant interviews with: schoolteachers to discuss the use of the screens in schools, program staff, and community members who had refused the intervention. Results Overall satisfaction and acceptance of the screens was very high, with only some operational and technical complaints relating to screen fragility and the installation process. However, the wider social context of urban violence and insecurity was a major barrier to screen acceptance. Lack of information dissemination and community collaboration were identified as project weaknesses. Conclusions The screens are widely accepted by the population, but the project implementation could be improved by reassuring the community of its legitimacy in the context of insecurity. More community engagement and better information sharing structures are needed. The screens could be a major new dengue prevention tool suitable for widespread use, if further research supports their entomological and epidemiological effectiveness and their acceptability in different social and environmental contexts. Further research is needed looking at the impact of insecurity of dengue prevention programmes. Electronic supplementary material The online version of this article (doi:10.1186/1471-2458-14-846) contains supplementary material, which is available to authorized users.

I Department olZoology, University 01Aberdeen, TilIydrone Avenue, Aberdeen, UK. AB24 2T2. e-mail: m.c.macswiney@abdn.ac.uk 2Secretaria de Ecologia, Gobierno del Estado de Yucatan, Direccion de Conservacion y Manejo de recursos naturales. Calle 64 #437 x 53 y 47-A. Col. Centro, Mel'ida Yucatan, Mexico. 3Departamento de Zoologia, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autonoma de Yucatan. A. P. 4-116/tzimna, Mirida, Yucatan, Mexico.