SciCombinator

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Concept: Costa Rica

174

A major interest has recently emerged in understanding how telomere shortening, mechanism triggering cell senescence, is linked to organism ageing and life history traits in wild species. However, the links between telomere length and key history traits such as reproductive performances have received little attention and remain unclear to date. The leatherback turtle Dermochelys coriacea is a long-lived species showing rapid growth at early stages of life, one of the highest reproductive outputs observed in vertebrates and a dichotomised reproductive pattern related to migrations lasting 2 or 3 years, supposedly associated with different environmental conditions. Here we tested the prediction of blood telomere shortening with age in this species and investigated the relationship between blood telomere length and reproductive performances in leatherback turtles nesting in French Guiana. We found that blood telomere length did not differ between hatchlings and adults. The absence of blood telomere shortening with age may be related to an early high telomerase activity. This telomere-restoring enzyme was formerly suggested to be involved in preventing early telomere attrition in early fast-growing and long-lived species, including squamate reptiles. We found that within one nesting cycle, adult females having performed shorter migrations prior to the considered nesting season had shorter blood telomeres and lower reproductive output. We propose that shorter blood telomeres may result from higher oxidative stress in individuals breeding more frequently (i.e., higher costs of reproduction) and/or restoring more quickly their body reserves in cooler feeding areas during preceding migration (i.e., higher foraging costs). This first study on telomeres in the giant leatherback turtle suggests that blood telomere length predicts not only survival chances, but also reproductive performances. Telomeres may therefore be a promising new tool to evaluate individual reproductive quality which could be useful in such species of conservation concern.

Concepts: Senescence, Organism, Turtle, Telomere, Costa Rica, Hawksbill turtle, Leatherback turtle, Sea turtle

147

This is the first comprehensive epidemiological analysis of rabies in Costa Rica. We characterized the occurrence of the disease and demonstrated its endemic nature in this country. In Costa Rica, as in other countries in Latin America, hematophagous vampire bats are the primary wildlife vectors transmitting the rabies virus to cattle herds. Between 1985 and 2014, a total of 78 outbreaks of bovine rabies was reported in Costa Rica, with documented cases of 723 dead cattle. Of cattle outbreaks, 82% occurred between 0 and 500 meters above sea level, and seasonality could be demonstrated on the Pacific side of the country, with significantly more outbreaks occurring during the wet season. A total of 1588 animal samples, or an average of 55 samples per year, was received by the veterinary authority (SENASA) for rabies diagnostic testing at this time. Of all samples tested, 9% (143/1588) were positive. Of these, 85.6% (125/1588) were from cattle; four dogs (0.3% [4/1588]) were diagnosed with rabies in this 30-year period. Simultaneously, an extremely low number (n = 3) of autochthonous rabies cases were reported among human patients, all of which were fatal. However, given the virus' zoonotic characteristics and predominantly fatal outcome among both cattle and humans, it is extremely important for healthcare practitioners and veterinarians to be aware of the importance of adequate wound hygiene and postexpositional rabies prophylaxis when dealing with both wild and domestic animal bites.

Concepts: Epidemiology, Spanish language, Veterinary medicine, Bat, Rabies, Latin America, Nicaragua, Costa Rica

69

Traditionally, animal species diversity and abundance is assessed using a variety of methods that are generally costly, limited in space and time, and most importantly, they rarely include a permanent record. Given the urgency of climate change and the loss of habitat, it is vital that we use new technologies to improve and expand global biodiversity monitoring to thousands of sites around the world. In this article, we describe the acoustical component of the Automated Remote Biodiversity Monitoring Network (ARBIMON), a novel combination of hardware and software for automating data acquisition, data management, and species identification based on audio recordings. The major components of the cyberinfrastructure include: a solar powered remote monitoring station that sends 1-min recordings every 10 min to a base station, which relays the recordings in real-time to the project server, where the recordings are processed and uploaded to the project website (arbimon.net). Along with a module for viewing, listening, and annotating recordings, the website includes a species identification interface to help users create machine learning algorithms to automate species identification. To demonstrate the system we present data on the vocal activity patterns of birds, frogs, insects, and mammals from Puerto Rico and Costa Rica.

Concepts: Biodiversity, Conservation biology, Evolution, Species, Machine learning, Automation, Puerto Rico, Costa Rica

36

Mesoamerican jaguars (Panthera onca) have been extirpated from over 77% of their historic range, inhabiting fragmented landscapes at potentially reduced population sizes. Maintaining and restoring genetic diversity and connectivity across human-altered landscapes has become a major conservation priority; nonetheless large-scale genetic monitoring of natural populations is rare. This is the first regional conservation genetic study of jaguars to primarily use fecal samples collected in the wild across five Mesoamerican countries: Belize, Costa Rica, Guatemala, Honduras, and Mexico. We genotyped 445 jaguar fecal samples and examined patterns of genetic diversity and connectivity among 115 individual jaguars using data from 12 microsatellite loci. Overall, moderate levels of genetic variation were detected (NA = 4.50 ± 1.05, AR = 3.43 ± 0.22, HE = 0.59 ± 0.04), with Mexico having the lowest genetic diversity, followed by Honduras, Guatemala, Belize, and Costa Rica. Population-based gene flow measures (FST = 0.09 to 0.15, Dest = 0.09 to 0.21), principal component analysis, and Bayesian clustering applied in a hierarchical framework revealed significant genetic structure in Mesoamerican jaguars, roughly grouping individuals into four genetic clusters with varying levels of admixture. Gene flow was highest among Selva Maya jaguars (northern Guatemala and central Belize), whereas genetic differentiation among all other sampling sites was moderate. Genetic subdivision was most pronounced between Selva Maya and Honduran jaguars, suggesting limited jaguar movement between these close geographic regions and ultimately refuting the hypothesis of contemporary panmixia. To maintain a critical linkage for jaguars dispersing through the Mesoamerican landscape and ensure long-term viability of this near threatened species, we recommend continued management and maintenance of jaguar corridors. The baseline genetic data provided by this study underscores the importance of understanding levels of genetic diversity and connectivity to making informed management and conservation decisions with the goal to maintain functional connectivity across the region.

Concepts: Guatemala, Population genetics, Central America, Nicaragua, Mesoamerica, Costa Rica, Tiger, Jaguar

29

The objective of this work is to assess the downscaling projections of climate change over Central America at 8-km resolution using the Eta Regional Climate Model, driven by the HadGEM2-ES simulations of RCP4.5 emission scenario. The narrow characteristic of continent supports the use of numerical simulations at very high-horizontal resolution. Prior to assessing climate change, the 30-year baseline period 1961-1990 is evaluated against different sources of observations of precipitation and temperature. The mean seasonal precipitation and temperature distribution show reasonable agreement with observations. Spatial correlation of the Eta, 8-km resolution, simulations against observations show clear advantage over the driver coarse global model simulations. Seasonal cycle of precipitation confirms the added value of the Eta at 8-km over coarser resolution simulations. The Eta simulations show a systematic cold bias in the region. Climate features of the Mid-Summer Drought and the Caribbean Low-Level Jet are well simulated by the Eta model at 8-km resolution. The assessment of the future climate change is based on the 30-year period 2021-2050, under RCP4.5 scenario. Precipitation is generally reduced, in particular during the JJA and SON, the rainy season. Warming is expected over the region, but stronger in the northern portion of the continent. The Mid-Summer Drought may develop in regions that do not occur during the baseline period, and where it occurs the strength may increase in the future scenario. The Caribbean Low-Level Jet shows little change in the future. Extreme temperatures have positive trend within the period 2021-2050, whereas extreme precipitation, measured by R50mm and R90p, shows positive trend in the eastern coast, around Costa Rica, and negative trends in the northern part of the continent. Negative trend in the duration of dry spell, which is an estimate based on evapotranspiration, is projected in most part of the continent. Annual mean water excess has negative trends in most part of the continent, which suggests decreasing water availability in the future scenario.

Concepts: Time, Precipitation, Climate, Weather, North America, Caribbean, Central America, Costa Rica

29

To develop effective environmental policies, we must understand the mechanisms through which the policies affect social and environmental outcomes. Unfortunately, empirical evidence about these mechanisms is limited, and little guidance for quantifying them exists. We develop an approach to quantifying the mechanisms through which protected areas affect poverty. We focus on three mechanisms: changes in tourism and recreational services; changes in infrastructure in the form of road networks, health clinics, and schools; and changes in regulating and provisioning ecosystem services and foregone production activities that arise from land-use restrictions. The contributions of ecotourism and other ecosystem services to poverty alleviation in the context of a real environmental program have not yet been empirically estimated. Nearly two-thirds of the poverty reduction associated with the establishment of Costa Rican protected areas is causally attributable to opportunities afforded by tourism. Although protected areas reduced deforestation and increased regrowth, these land cover changes neither reduced nor exacerbated poverty, on average. Protected areas did not, on average, affect our measures of infrastructure and thus did not contribute to poverty reduction through this mechanism. We attribute the remaining poverty reduction to unobserved dimensions of our mechanisms or to other mechanisms. Our study empirically estimates previously unidentified contributions of ecotourism and other ecosystem services to poverty alleviation in the context of a real environmental program. We demonstrate that, with existing data and appropriate empirical methods, conservation scientists and policymakers can begin to elucidate the mechanisms through which ecosystem conservation programs affect human welfare.

Concepts: Biodiversity, Poverty, Empiricism, Empirical, Policy, Empirical research, Poverty reduction, Costa Rica

28

A comprehensive taxonomic study is presented for the four genera and 286 species of the doryctine tribe Heterospilini occurring in Costa Rica. The tribe is represented almost entirely by the 280 species of the genus Heterospilus Haliday. Keys for identification of the genera and species are provided and the genera and species are described and illustrated. An interactive key to the species of Heterospilus also was prepared using Lucid Builder. The following new genus and species are described from Costa Rica: Paraheterospilus gen. n., P. ceciliaensis sp. n., P. eumekus sp. n., P. wilbotgardus sp. n., Heterospilus achi sp. n., H. achterbergi sp. n., H. aesculapius sp. n., H. agujas sp. n., H. agujasensis sp. n., H. alajuelus sp. n., H. albocoxalis sp. n., H. alejandroi sp. n., H. amuzgo sp. n., H. angelicae sp. n., H. angustus sp. n., H. aphrodite sp. n., H. apollo sp. n., H. arawak sp. n., H. areolatus sp. n., H. artemis sp. n., H. athena sp. n., H. attraholucus sp. n., H. aubreyae sp. n., H. austini sp. n., H. azofeifai sp. n., H. bacchus sp. n., H. barbalhoae sp. n., H. bennetti sp. n., H. bicolor sp. n., H. boharti sp. n., H. borucas sp. n., H. braeti sp. n., H. brethesi sp. n., H. breviarius sp. n., H. brevicornus sp. n., H. bribri sp. n., H. brullei sp. n., H. bruesi sp. n., H. cabecares sp. n., H. cacaoensis sp. n., H. cachiensis sp. n., H. cameroni sp. n., H. cangrejaensis sp. n., H. careonotaulus sp. n., H. caritus sp. n., H. carolinae sp. n., H. cartagoensis sp. n., H. catiensis sp. n., H. catorce sp. n., H. cero sp. n., H. chaoi sp. n., H. chilamatensis sp. n., H. chocho sp. n., H. chorotegus sp. n., H. chorti sp. n., H. cinco sp. n., H. cocopa sp. n., H. colliletus sp. n., H. colonensis sp. n., H. complanatus sp. n., H. conservatus sp. n., H. cora sp. n., H. corcovado sp. n., H. corrugatus sp. n., H. costaricensis sp. n., H. cressoni sp. n., H. cuatro sp. n., H. curtisi sp. n., H. cushmani sp. n., H. dani sp. n., H. demeter sp. n., H. dianae sp. n., H. diecinueve sp. n., H. dieciocho sp. n., H. dieciseis sp. n., H. diecisiete sp. n., H. diez sp. n., H. doce sp. n., H. dos sp. n., H. dulcus sp. n., H. eberhardi sp. n., H. ektorincon sp. n., H. emilius sp. n., H. empalmensis sp. n., H. enderleini sp. n., H. escazuensis sp. n., H. fahringeri sp. n., H. fischeri sp. n., H. flavidus sp. n., H. flavisoma sp. n., H. flavostigmus sp. n., H. foersteri sp. n., H. fonsecai sp. n., H. fournieri sp. n., H. gahani sp. n., H. garifuna sp. n., H. gauldi sp. n., H. golfodulcensis sp. n., H. gouleti sp. n., H. granulatus sp. n., H. grisselli sp. n., H. guanacastensis sp. n., H. guapilensis sp. n., H. hachaensis sp. n., H. halidayi sp. n., H. hansoni sp. n., H. hansonorum sp. n., H. haplocarinus sp. n., H. hedqvisti sp. n., H. hera sp. n., H. heredius sp. n., H. hespenheidei sp. n., H. holleyae sp. n., H. huddlestoni sp. n., H. huetares sp. n., H. hypermekus sp. n., H. itza sp. n., H. ixcatec sp. n., H. ixil sp. n., H. jabillosensis sp. n., H. jakaltek sp. n., H. janzeni sp. n., H. jennieae sp. n., H. jonmarshi sp. n., H. jupiter sp. n., H. kellieae sp. n., H. kiefferi sp. n., H. kikapu sp. n., H. kulai sp. n., H. kuna sp. n., H. lapierrei sp. n., H. lasalturus sp. n., H. laselvus sp. n., H. leenderti sp. n., H. leioenopus sp. n., H. leiponotaulus sp. n., H. lenca sp. n., H. levis sp. n., H. leviscutum sp. n., H. levitergum sp. n., H. limonensis sp. n., H. longinoi sp. n., H. longisulcus sp. n., H. longius sp. n., H. luteogaster sp. n., H. luteoscutum sp. n., H. luteus sp. n., H. macrocarinus sp. n., H. macrocaudatus sp. n., H. magnus sp. n., H. malaisei sp. n., H. mam sp. n., H. maritzaensis sp. n., H. mars sp. n., H. masneri sp. n., H. masoni sp. n., H. mellosus sp. n., H. menkei sp. n., H. mercury sp. n., H. milleri sp. n., H. miskito sp. n., H. mixtec sp. n., H. monteverde sp. n., H. mopanmaya sp. n., H. muertensis sp. n., H. muesebecki sp. n., H. nahua sp. n., H. neesi sp. n., H. nemestrinus sp. n., H. nephilim sp. n., H. nephus sp. n., H. nigracapitus sp. n., H. nigragonatus sp. n., H. nigricoxus sp. n., H. nixoni sp. n., H. noyesi sp. n., H. nueve sp. n., H. nunesi sp. n., H. once sp. n., H. orbitus sp. n., H. orosi sp. n., H. paloverde sp. n., H. pappi sp. n., H. parkeri sp. n., H. parvus sp. n., H. pech sp. n., H. penosa sp. n., H. petiolatus sp. n., H. petralbus sp. n., H. phaeocoxus sp. n., H. phaeoskelus sp. n., H. pharkidodus sp. n., H. phytorius sp. n., H. pitillaensis sp. n., H. poqomchi sp. n., H. poqomom sp. n., H. puertoviejoensis sp. n., H. puntarensis sp. n., H. qanjobal sp. n., H. quickei sp. n., H. quitirrisi sp. n., H. racostica sp. n., H. rama sp. n., H. ramirezi sp. n., H. ratzeburgi sp. n., H. reagani sp. n., H. reinhardi sp. n., H. retheospilus sp. n., H. rhabdotus sp. n., H. ricacosta sp. n., H. rinconensis sp. n., H. robbieae sp. n., H. rohweri sp. n., H. rojasi sp. n., H. romani sp. n., H. rugosus sp. n., H. sabrinae sp. n., H. saminae sp. n., H. sanjosensis sp. n., H. santarosensis sp. n., H. sanvitoensis sp. n., H. saturn sp. n., H. seis sp. n., H. sergeyi sp. n., H. sharkeyi sp. n., H. shawi sp. n., H. shenefelti sp. n., H. shonan sp. n., H. siete sp. n., H. similis sp. n., H. sinuatus sp. n., H. smithi sp. n., H. spiloheterus sp. n., H. staryi sp. n., H. stelfoxi sp. n., H. strazanaci sp. n., H. sumo sp. n., H. szepligeti sp. n., H. terrabas sp. n., H. thereospilus sp. n., H. tobiasi sp. n., H. tolupan sp. n., H. townesi sp. n., H. trece sp. n., H. tres sp. n., H. tricolor sp. n., H. trienta sp. n., H. tuberculatus sp. n., H. turrialbaensis sp. n., H. tzutujil sp. n., H. ugaldei sp. n., H. uno sp. n., H. variabilis sp. n., H. veinte sp. n., H. veintidos sp. n., H. veintitres sp. n., H. veintiuno sp. n., H. vierecki sp. n., H. villegasi sp. n., H. vittatus sp. n., H. vulcanus sp. n., H. wahli sp. n., H. warreni sp. n., H. washingtoni sp. n., H. wesmaeli sp. n., H. whartoni sp. n., H. whitfieldi sp. n., H. wildi sp. n., H. wilkinsoni sp. n., H. wrightae sp. n., H. xanthus sp. n., H. xerxes sp. n., H. xinca sp. n., H. yaqui sp. n., H. ypsilon sp. n., H. zapotec sp. n., H. zeus sp. n., H. zitaniae sp. n., H. zoque sp. n., H. zunigai sp. n., H. zurquiensis sp. n. One new combination is proposed, Pioscelus costaricensis (Marsh) comb. n.

Concepts: Costa Rica, Athena

27

Recent investigations have demonstrated that unusually ‘hairy’ yeti crabs within the family Kiwaidae associate with two predominant filamentous bacterial families, the Epsilon and Gammaproteobacteria. These analyses, however, were based on samples collected from a single body region, the setae of pereopods. To more thoroughly investigate the microbiome associated with Kiwa puravida, a yeti crab species from Costa Rica, we utilized barcoded 16S rRNA amplicon pyrosequencing, as well as microscopy and terminal restriction fragment length polymorphism analysis. Results indicate that, indeed, the bacterial community on the pereopods is far less diverse than on the rest of the body (Shannon indices ranged from 1.30-2.02 and 2.22-2.66, respectively). Similarly, the bacterial communities associated with juveniles and adults were more complex than previously recognized, with as many as 46 bacterial families represented. Ontogenetic differences in the microbial community, from egg to juvenile to adult, included a dramatic under-representation of the Helicobacteraceae and higher abundances of both Thiotrichaceae and Methylococcaceae for the eggs, which paralleled patterns observed in another bacteria-crustacean symbiosis. The degree to which abiotic and biotic feedbacks influence the bacterial community on the crabs is still not known, but predictions suggest that both the local environment and host-derived factors influence the establishment and maintenance of microbes associated with the surfaces of aquatic animals.

Concepts: Archaea, Bacteria, Microbiology, Crustacean, Microorganism, Crab, Costa Rica, Kiwa hirsuta

27

Drought tolerance is a key factor for the establishment and survival of tree species in tropical ecosystems. Specific mechanisms of drought resistance can be grouped into four functional ecotypes based on differences in leaf fall behavior: deciduous, brevi-deciduous, stem succulent and evergreen. To identify the key factors influencing phenology and cambial activity and thus drought tolerance, we tested the stomatal conductance, leaf water potential and stable carbon isotopes in the leaves and wood of 12 species from a tropical dry forest in Costa Rica. With wood anatomical techniques, we further studied seasonal cambial activity and a suite of wood traits related to water transport for each of the functional ecotypes. Using a principal component analysis, we identified two groups of variables that can be related to (i) hydraulic conductivity and (ii) control of transpiration and water loss. Hydraulic conductivity is controlled by vessel size as the limiting variable, water potential as the driving force and wood density as the stabilizing factor of the anatomical structure of an effective water transport system. Stomatal control plays a major role in terms of water loss or saving and is the dominant factor for differences in phenological behavior. Stem succulent species in particular developed a rarely identified but highly effective strategy against drought stress, which makes it a successful pioneer species in tropical dry forests.

Concepts: Hydrology, Factor analysis, Principal component analysis, Plant physiology, Leaf, Costa Rica, Deciduous, Tropical and subtropical dry broadleaf forests

26

We previously screened 400 elderly Costa Ricans for neurodegenerative disease. Those reporting occupational pesticide exposure (18%) had an increased Parkinson׳s disease (PD) risk (OR 2.57, 95% CI 0.91-7.26), and worse cognition (Mini-Mental States Exam (MMSE) 24.5 versus 25.9 points, p=0.01). We subsequently measured long-lasting organochlorine pesticides (β-HCH, DDE, DDT, and dieldrin) in a sub-sample (n=89). Dieldrin and β-HCH have been linked to PD, and DDE to Alzheimer׳s disease.

Concepts: Neurodegeneration, Pesticide, Insecticide, DDT, Neurodegenerative diseases, Costa Rica