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Harvestmen exhibit substantial responses to environmental conditions, disturbances, and modifications of their habitat. We examined the abundance and species distribution of harvestmen along an elevational gradient in the Luquillo Experimental Forest (LEF) on Puerto Rico 6-12 weeks before and 9-10 months after Hurricane Maria passed over the island in September, 2017. This provided a unique opportunity to examine the effects of a major storm on litter-dwelling arthropod populations, as the storm led to a much greater abundance of leaf litter and downed branches. The abundance of harvestmen was measured in quadrat samples from 300 to 1,000 m elevation using Winkler samplers. We observed greater harvestmen abundance post-storm, which was similar to the results for most other arthropod groups. Pre-storm, harvestmen showed greater abundance in palm habitat, as compared to forests that were a mix of broadleaf and palm vegetation. Across all sampling periods, harvestmen were most abundant at low to medium elevations (300-600 m), especially for the two dominant taxa (Stygnomma spinula and Metacynortoides obscura obscura). Our findings are similar to results obtained from manipulative studies in the LEF several years prior to the hurricane. A challenge for the future is to understand the ways that the projected increase in storm severity due to climate change can affect various invertebrate groups such as harvestmen, and how tropical forests can remain resilient to such disturbances. [ABSTRACT FROM AUTHOR]

Disturbances like hurricanes can affect diversity and community composition, which may in turn affect ecosystem function. We examined how a simulated hurricane disturbance affected insect communities inhabiting the phytotelma (plant‐held waters) of Heliconia caribaea in the Luquillo Experimental Forest of eastern Puerto Rico, a tropical island that frequently experiences hurricanes. We hypothesized that disturbance would alter diversity and that larger Heliconia would attract more species following disturbance due to the area‐diversity relationship described by the Theory of Island Biogeography. Individual flower parts (bracts) of Heliconia inflorescences (racemes) were artificially disturbed via removal of existing insect communities, then after refilling with water, cohorts of Heliconia were destructively sampled biweekly for 6 weeks to assess recolonization patterns of α (bract level), β, and γ (summed across bracts; raceme level) diversity over time and across raceme sizes. Although we found no support for our hypothesis about the effect of raceme size on recolonization, our hypothesis regarding recolonization patterns over time was supported; species richness, evenness, and abundance of bracts increased directly after the disturbance and then decreased below pre‐disturbance levels, and community composition at the raceme level changed significantly over time during recolonization. β Diversity was also greater in smaller racemes compared to larger racemes, suggesting high heterogeneity across bracts of Heliconia racemes exacerbated by raceme size and age. Overall, our results highlight the importance of scale and appropriate measurements of diversity (particularly α) in experiments aiming to extrapolate conclusions about the ecological impacts of disturbances across different habitats and ecosystems. [ABSTRACT FROM AUTHOR]

The ability of ecosystems to regulate water quality and flood events has been linked to health outcomes, including mosquito-borne illnesses. In the San Juan Bay Estuary watershed of Puerto Rico, habitat alterations and land-use development have disrupted watershed hydrology, exacerbating wastewater discharges and subjecting some neighborhoods to frequent flooding events. In 2016, the mosquito-borne illness Zika became a new cause for concern. We hypothesized that nutrient-enriched flood water could provide pulses of supplemental nutrients to local mosquito populations. We conducted a field study in six neighborhoods adjacent to the estuary to assess whether environmental variability of nutrient inputs could be linked to breeding habitat containers, Aedes aegypti larvae and adults, and the acquisition of Zika virus by adult mosquitoes. The most frequently flooded neighborhood had consistently higher levels of nitrogen in estuary water, leaf detritus, containers, and adult mosquitoes compared to other neighborhoods. Adult body nitrogen was significantly related to both nitrogen content of containers and leaf detritus from the local trapping area. Disseminated Zika concentration in adult Ae. aegypti tended to decrease as body carbon and nitrogen increased. Our study provides preliminary evidence that environmental variability in nutrient inputs can influence viral acquisition by mosquito vectors. This suggests that management actions to reduce flooding and improve water quality should go hand-in-hand with more traditional vector control methods, such as aerial spraying, to help control spread of vector-borne diseases. [ABSTRACT FROM AUTHOR]

• 31 species of mosquitoes were collected on the islands of Puerto Rico and Vieques. • One new species record was identified Aedes obturbator (Dyar and Knab). • The invasive Aedes albopictus (Skuse) was not collected from either island. We conducted an island-wide survey of the Caribbean islands Puerto Rico and Vieques, U.S.A. during late 2018 and early 2019 to document the current richness of mosquitoes (Diptera: Culicidae). We used a combination of larval surveys and adult trapping using baited CDC light traps and BG-Sentinel traps across 41 of the 78 municipalities. We collected 9 genera, 12 subgenera, and 31 species, which when combined with past studies yields 44 species on the islands. We also note species occurrences across habitat types and elevations from around the islands. One new record, Aedes (Ochlerotatus) obturbator Dyar and Knab, is noted. However we found no evidence of the presence of Aedes albopictus (Skuse), an invasive found throughout the Caribbean, or Aedes (Fredwardsius) vittatus (Bigot), an exotic species recently reported in the Dominican Republic and Cuba. Habitat associations and information regarding the medical importance of species are also included. Given that the islands often experience outbreaks of several arboviruses, obtaining a complete picture of the species present is of high importance. [ABSTRACT FROM AUTHOR]

Simple Summary: Understanding the biodiversity of urban ecosystems is critical for management of invasive and pest species, conserving native species, and disease control. Mosquitoes (Culicidae) are ubiquitous and abundant in urban ecosystems, and rely on blood meals taken from vertebrates. We used DNA from freshly blood-fed mosquitoes to characterize the diversity of vertebrate host species in the San Juan Metropolitan Area, Puerto Rico. We collected two mosquito species that fed on a variety of vertebrates. Culex quinquefasciatus fed on 17 avian taxa (81.2% of blood meals), seven mammalian taxa (17.9%), and one reptilian taxon (0.85%). Aedes aegypti blood meals were from a less diverse group, with two avian taxa (11.1%) and three mammalian taxa (88.9%) identified. Domestic chickens dominated the blood meals of Cx. quinquefasciatus, both temporally and spatially, and no statistically significant shift from birds to mammals was detected. The species we detected from the mosquito blood meals provided a snapshot of the vertebrate community in the San Juan Metropolitan Area, most of which were domestic species. However, we also identified a variety of native and nonnative wild species. These results add knowledge about potential ecological factors that impact vector-borne disease management in urban habitats. Urban ecosystems are a patchwork of habitats that host a broad diversity of animal species. Insects comprise a large portion of urban biodiversity which includes many pest species, including those that transmit pathogens. Mosquitoes (Diptera: Culicidae) inhabit urban environments and rely on sympatric vertebrate species to complete their life cycles, and in this process transmit pathogens to animals and humans. Given that mosquitoes feed upon vertebrates, they can also act as efficient samplers that facilitate detection of vertebrate species that utilize urban ecosystems. In this study, we analyzed DNA extracted from mosquito blood meals collected temporally in multiple neighborhoods of the San Juan Metropolitan Area, Puerto Rico to evaluate the presence of vertebrate fauna. DNA was collected from 604 individual mosquitoes that represented two common urban species, Culex quinquefasciatus (n = 586) and Aedes aegypti (n = 18). Culex quinquefasciatus fed on 17 avian taxa (81.2% of blood meals), seven mammalian taxa (17.9%), and one reptilian taxon (0.85%). Domestic chickens dominated these blood meals both temporally and spatially, and no statistically significant shift from birds to mammals was detected. Aedes aegypti blood meals were from a less diverse group, with two avian taxa (11.1%) and three mammalian taxa (88.9%) identified. The blood meals we identified provided a snapshot of the vertebrate community in the San Juan Metropolitan Area and have potential implications for vector-borne pathogen transmission. [ABSTRACT FROM AUTHOR]

Recurrence of local transmission of Zika virus in Puerto Rico is a major public health risk to the United States, where mosquitoes Aedes aegypti (Linnaeus) and Aedes mediovittatus (Coquillett) are abundant. To determine the extent to which Ae. mediovittatus are capable of transmitting Zika virus and the influence of viremia, we evaluated infection and transmission in Ae. mediovittatus and Ae. aegypti from Puerto Rico using serial dilutions of infectious blood. Higher doses of infectious blood resulted in greater infection rates in both mosquitoes. Aedes aegypti females were up to twice as susceptible to infection than Ae. mediovittatus, indicating a more effective midgut infection barrier in the latter mosquito species. Aedes aegypti exhibited higher disseminated infection (40-95%) than Ae. mediovittatus (<5%), suggesting a substantial midgut escape barrier in Ae. mediovittatus. For Ae. aegypti, transmission rates were low over a range of doses of Zika virus ingested, suggesting substantial salivary gland barriers., (© The Author(s) 2021. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)