TY - JOUR T1 - Size dependent occurence of different types of web decorations and a barrier web in the tropical spider Argiope argentata (Fabricius 1775) (Araneae Araneidae) JF - Tropical Zoology Y1 - 2008 A1 - Uhl, Gabriele SP - 97 EP - 108 KW - barrier web KW - ontogenetic changes KW - plasticity KW - predator-prey relationship KW - St Andrews cross spider KW - stabilimentum KW - web decoration AB -

Web decorations occur in a wide range of spiders and are constructed using various materials such as leaves, carcasses or silk. Silk decorations, so called stabilimenta, have attracted most attention since they are an obvious feature of the webs of several orb web species and are highly visible to the human eye. Silk decorations are mainly discshaped, linear or cruciate. The functions of silk decorations remain a controversial issue. More comparative and experimental work is needed, apart from the assessment of environmental prerequisites for the construction of web decorations. I collected data on the occurrence and type of silk decorations, along with a measure of body size, for a population of the tropical spider Argiope argentata (Fabricius 1775) in the Bijagual biological reserve in Costa Rica. In addition, I recorded whether a barrier web was present or not. I found that whether a discoid or cruciate decoration was produced significantly depended on body size: smaller spiders constructed mainly discoid decorations whereas larger spiders constructed at least part of a cruciate decoration or none at all. Barrier webs predominantly occurred in smaller spiders and were rarely present in larger spiders. The data contradict those of an earlier census performed on the Galapagos Islands, which suggested that the difference in biotic and abiotic environmental parameters not only causes differences in variability of web building behaviour but near complete reversal.

VL - 21 ER - TY - JOUR T1 - Revision of the Neotropical general Bocageopsis, Onychopetalum, and Unonopsis (Annonaceae) JF - Blumea Y1 - 2007 A1 - Maas, Paul J.M. A1 - Lubbert Y. Th. Westra A1 - Marloes Vermeer SP - 413 EP - 554 AB -

A taxonomic revision is made of the Neotropical genera Bocageopsis, Onychopetalum, and Unonopsis (Annonaceae). The closeness of these three genera was expressed by Fries when he placed them in his (informal) Unonopsis group (Fries, 1959), and the close relationship is supported by more recent phylogenetic research as well. Four species are recognized in Bocageopsis and two species in Onychopetalum. Unonopsis is by far the largest of the three genera with close to 50 species, of which no less than 23 species are here described as new. One species (Unonopsis umbilicata) had to be shelved as insufficiently known for lack of data, and another, obviously new, species from Colombia is too incomplete and is described provisionally as Unonopsis spec. A.

Several keys are provided, one for the genera and one each for the species of Bocageopsis and Onychopetalum. For the species of Unonopsis a key to all species and, in addition, a key to the species of Mexico and Central America are provided. The species treatments include full descriptions, geographical and ecological notes, distribution maps, synonymy, taxonomic notes, and vernacular names. A complete list of exsiccatae is appended.

Parallel to the taxonomic revision, a leaf anatomical survey was made by E.-J. van Marle, and is included here.

VL - 52 ER - TY - JOUR T1 - Assessing species traits and landscape relationships of the mammalian carnivore community in a neotropical biological corridor JF - Biodiversity and Conservation Y1 - 2016 DO - 10.1007/s10531-016-1089-7 A1 - Pardo Vargas, Lain E. A1 - Cove, Michael V. A1 - Spinola, R. Manuel A1 - de la Cruz, Juan Camilo A1 - Saénz, Joel C. SP - 739 EP - 752 KW - Biological corridor KW - camera traps KW - Carnivores KW - Mesopredators KW - Occupancy models KW - Omnivores AB -

Mammalian carnivores play an important role in regulating food webs and ecosystems. While many carnivore populations are facing various threats such as habitat loss and fragmentation, poaching, and illegal trade, others have adapted to human-dominated landscapes. Information about Neotropical carnivore communities in particular is limited, especially in disturbed landscapes. We conducted a camera trap survey at 38 sites across the San Juan–La Selva Biological Corridor in Costa Rica to assess occupancy and detection probabilities of the carnivore community. We developed hypotheses within a likelihood-based framework in order to determine the landscape features and species traits (diet and size) that influenced their occupancy. We detected nine of the 13 native carnivores predicted to occur in the corridor. When modeled separately, each species responded to land cover changes differently, suggesting no strong community-wide predictors of occupancy. We then modeled three separate guilds within the carnivore community: omnivorous mesopredators, obligate carnivorous mesopredators, and apex predators. These community guild models revealed a negative relationship between omnivorous mesopredators and increasing forest and tree plantation cover, suggesting omnivores utilize forest fragments and edge habitats in agricultural landscapes. Obligate carnivorous mesopredator models did not reveal any strong habitat relationships, but landscape effects tended to contradict our a priori predictions. Apex predators were positively associated with increasing forest and tree plantation cover, protected areas, and increasing distances to villages. Alarmingly, apex predators and obligate carnivorous mesopredators were generally rare within the biological corridor. A lack of top-down control alone might result in heightened occupancy for all mesopredators, but because the community is dominated by omnivorous species, bottom-up release from human-induced land cover changes and resource provision may better explain their high occupancy.

VL - 25 UR - http://link.springer.com/10.1007/s10531-016-1089-7 IS - 4 JO - Biodivers Conserv ER - TY - JOUR T1 - Factors influencing the occurrence of the Endangered Baird's tapir Tapirus bairdii : potential flagship species for a Costa Rican biological corridor JF - Oryx Y1 - 2014 DO - 10.1017/S0030605313000070 A1 - Cove, Michael V. A1 - Pardo Vargas, Lain E. A1 - de la Cruz, Juan Camilo A1 - Spinola, R. Manuel A1 - Jackson, Victoria L. A1 - Saénz, Joel C. A1 - Chassot, Olivier SP - 402 EP - 409 AB -

Baird’s tapir Tapirus bairdii is categorized as Endangered on the IUCN Red List and is considered rare and locally extirpated from most of its historic range in Costa Rica. We conducted camera-trap and track surveys at 38 forested sites in and around the San Juan–La Selva Biological Corridor in the Northern Zone of Costa Rica. Cameras were set along established game trails and natural funnels and operated for 14–38 days per site. Additionally, we documented tapir tracks at many sites. We used survey photographs and track presence to create detection histories to estimate the habitat and survey-specific variables that influence the probability of detection and the probability of occurrence of Baird’s tapir. The two major protected areas within and adjacent to the corridor were most positively associated with tapir occurrence, and forest cover and native and exotic tree plantations were also positively associated with tapirs’ use of sites. Although the Baird’s tapir is rare, our findings suggest that it is more resilient and better able to use available habitat in the fragmented corridor than previously thought. This is most likely a consequence of increased forest cover from reforestation and tree plantations and limited hunting pressure. Given its charismatic nature we recommend that Baird’s tapir could be used as a flagship species for the San Juan–La Selva Biological Corridor, to raise local awareness about conservation and increase economic growth from ecotourism.

VL - 48 UR - http://www.journals.cambridge.org/abstract_S0030605313000070https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0030605313000070 IS - 03 JO - Oryx ER - TY - CONF T1 - Native tree survivorship and growth rates in mixed species plots: Neotropical timber plantations can promote associated biodiversity. T2 - 100th Ecological Society of America Annual Meeting Y1 - 2015 A1 - Foster, Paul F. A1 - Cris G. Hochwender A1 - Samantha Montgomery A1 - Kelsey Williams A1 - Stephanie Tran A1 - Christie Hubbard A1 - Nicole Kreuzman KW - Costa Rica KW - reforestation KW - restoration AB -

Background/Question/Methods

Forests have been converted at an alarming rate in tropical and subtropical regions, and tree plantations are replacing both primary and secondary forests. Unfortunately, tree plantations are typically monocultures of non-native species with understories maintained devoid of all other plants. More data on growth rates of native timber species and potential associated biodiversity are needed if native species are to be utilized effectively in diverse plantation systems. This study analyzed survivorship and growth rates of native tree species and associated plant diversity colonizing mixed tree plantations in a lowland wet forest in Costa Rica. Seven native species were planted in abandoned pasture in two sites. Survival, height, and diameter at breast height (DBH) were periodically monitored in six plots of 49 trees each over 13 years. In addition, understory diversity associated with the plantations was examined. Two parallel transects were run in five of the six plots. Sets of 12 quadrats (0.5 m x 0.5 m) were created within each transect to measure percent cover. Within each plot, 2x20 m transects were used to tally and measure DBH for all stems above 1.0 m.  All individual plants in quadrats and transects were identified to species.

Results/Conclusions

Two tree species grew rapidly, achieving mean DBHs greater than 20 cm after 13 years of growth—Cordia bicolor and Terminalia amazonia. T. amazonia is an economically useful species that produces hard, durable wood used for furniture, paneling, and flooring. While C. bicolor is useful only for fence posts, its rapid growth makes it a valuable early successional tree. Moreover individuals of C. bicolor have begun reproducing, thereby attracting frugivores to the plots where it occurs. Associated plant diversity in the plantations was high with 142 species from 57 families colonizing the understory of the plantations in the 400 m2 area sampled. These findings demonstrate that using a mixture of native tree species in a plantation setting can provide trees of timber value, while also allowing for rapid re-establishment of understory diversity. We discuss our findings in the context of a mixed-species tree plantation providing harvestable timber while also supporting biodiversity and ecosystem services.

JF - 100th Ecological Society of America Annual Meeting CY - Baltimore, Maryland ER - TY - JOUR T1 - A new species of Macbrideola from Costa Rica JF - Boletín de la Sociedad Micológica de Madrid Y1 - 2014 A1 - Walker, L. M. A1 - Moreno, G. A1 - Stephenson, S. L. KW - ecology KW - mycobiota KW - Protozoa KW - Reserva Ecológica Bijagual KW - Stemonitales KW - taxonomy AB -

Macbrideola spinosispora is described as a species new to science based on material collected in a lowland tropical rainforest in Costa Rica. This new species can be distinguished from other members of the genus by the violaceous color of the sporotheca, the loose and flexuous capillitium and the conspicuously spiny spores. Images are provided of diagnostic morphological features.

VL - 38 ER - TY - CONF T1 - Neoichnology of Costa Rican bats: track morphology and trackmaking ability of phyllostomid and emballonurid bats T2 - 2014 Annual Meeting of the Geological Society of America Y1 - 2014 A1 - Jones, M. T. A1 - Hasiotis, S. T. KW - Reserva Ecológica Bijagual AB -

Of the four groups of animals to have developed powered flight, only bats are unknown from the trace fossil record. In comparison, pterosaurs, flying quadrupeds like bats, are recognized from at least three valid ichnogenera that are known from every continent except Antarctica. With a body fossil record of over 52 million years combined with the rapid colonization of most continents, bats are ideal candidates to have produced trace fossils. Modern bats display a wide range of terrestrial abilities, from aerial insectivores, to those that forage for insects and other arthropods on the ground, to the New Zealand short-tailed bat and common vampire bat that possess a suite of terrestrial behaviors including running and hopping. We present the first broad survey of trackmaking ability in an ecologically diverse family of Neotropical bats, the Phyllostomidae, as well as representatives from another New World family, the Emballonuridae. In late June and early July 2014, trackmaking trials were conducted with members of the five Costa Rican subfamilies of Phyllostomidae: Carollia perspicillata and C. sowelli (Carollinae), Lonchorhina aurita and Micronycteris microtus (Phyllostominae), Demanura phaeotis and Artibeus lituratus (Stenodermatinae), Desmodus rotundus (Desmodontinae), and Hylonycteris underwoodi (Glossophaginae), and the emballonurid Saccopteryx bilineata. These bats represent different ecological niches and hindlimb morphologies resulting in differing terrestrial behaviors and track morphology. Most bats were limited to an uncoordinated terrestrial gait that we have termed the breaststrokelike crawl, while a few, notably Desmodus, proved terrestrially adept. Tracks produced corresponded primarily to the forelimbs, while hindlimb tracks were much less likely to be preserved. Various track morphologies produced include linear and arcuate tracks corresponding to digit one of the manus, and isolated and clustered pedal traces featuring four or five subparallel digit impressions. Only Desmodus produced definitive trackways. This research will better illuminate what bat tracks and trackways may look like in the rock record, and future research will address how trackways, such as those produced by Desmodus, compare to pterosaur trackways.

JF - 2014 Annual Meeting of the Geological Society of America CY - Vancouver, British Columbia ER - TY - CONF T1 - Neoichnology and Tracemaking Behavior of Desmodus rotundus T2 - 44th Annual Symposium of the North American Society for Bat Research Y1 - 2014 A1 - Jones, Matthew A1 - Hasiotis, Stephen KW - Reserva Ecológica Bijagual AB -

Trace fossils are useful tools for interpreting the behavior of extinct and ancient organisms as well as providing clues to the potential distribution and occurrence of organisms in areas where body fossils are absent. Tracks and trackways of flying organisms are present in the fossil record, including insects, birds, and pterosaurs; bat trace fossils, however, are not known. The absence of bat trace fossils may be due to their small size, unfavorable preservation conditions of the environment, or misidentification. The lack of traces is likely not due to an aversion to terrestrial locomotion, as modern bats display a range of terrestrial abilities from strictly aerial insectivores to the unique terrestrial behaviors of the common vampire bat (Desmodus rotundus) and the New Zealand short-tailed bat (Mystacina tuberculata). We present the first study of the trackway-making ability of the common vampire bat, and compare it to the terrestrially inept genus Carollia. Four Desmodus rotundus were captured at Reserva Ecológica Bijagual de Sarapiquí in the Caribbean lowlands of Costa Rica during early summer 2014. A custom-built Plexiglas® and PVC enclosure allowed the bats to walk across sediment but prevented them from flying. The resulting trackmaking behaviors were video recorded and trackways were cast with plaster and analyzed. All Desmodus exhibited a more typical quadrupedal gait than did Carollia. Desmodus, in contrast, did not display the breaststrokelike crawl performed by the less terrestrially-adept species. Trackways produced by Desmodus are characterized by deep manus impressions and scattered, more infrequent pedal tracks.

JF - 44th Annual Symposium of the North American Society for Bat Research CY - Albany, New York ER - TY - JOUR T1 - Effect of clonal reproduction on genetic structure in Pentaclethra macroloba (Fabaceae: Mimosoideae) JF - Revista de Biología Tropical Y1 - 2014 A1 - Keith D. Gaddis A1 - Helen L. Zukin A1 - Inca A. Dieterich A1 - Elizabeth Braker A1 - Victoria L. Sork KW - Costa Rica KW - genetic diversity KW - La Selva Biological Station KW - Reserva Ecológica Bijagual KW - sprouting KW - tropical forest VL - 62 IS - 2 ER - TY - JOUR T1 - Molecular phylogenetics and morphological evolution of Thunbergioideae (Acanthaceae) JF - Taxon Y1 - 2008 A1 - Borg, Agneta Julia A1 - McDade, Lucinda A. A1 - Schönenberger, Jürg KW - Acanthaceae KW - chloroplast DNA KW - morphology KW - phylogeny KW - Reserva Ecológica Bijagual KW - Thunbergioideae AB -

Based on nucleotide sequences from three chloroplast DNA regions (rps16, rpl16, trnT-trnL), we infer detailed phylogenetic relationships within the subfamily Thunbergioideae (Acanthaceae) and among major lineages of the family as a whole. Taxa were sampled to cover the geographic distribution of Thunbergioideae and to include all subgenera of the largest genus Thunbergia. All other major lineages of Acanthaceae were sampled to test monophyly and intrafamilial position of Thunbergioideae. Both parsimony and Bayesian analyses support Thunbergioideae as monophyletic. The mangrove genus Avicennia is consistently placed as sister to Thunbergioideae although with only moderate support. Thunbergia and Mendoncia are both monophyletic in all analyses, and Mendoncia is placed as sister to Thunbergia plus Pseudocalyx. Relationships within the two largest genera Mendoncia and Thunbergia are highly resolved and most branches are strongly supported. Our results suggest that the existing morphology-based classification of Thunbergia partially holds, but needs revision. Based on the phylogenetic relationships we found it likely that a twining habit is ancestral for the genus Thunbergia. The thecal awns, characteristic for many species in the genus, have probably evolved from unicellular bristles. Longitudinal dehiscence over the whole length of the thecae, which is present in many Thunbergia species, most likely evolved from short slits or pores as present in Pseudocalyx and Mendoncia.

VL - 57 IS - 3 ER - TY - JOUR T1 - Observations of cavity-roosting behavior in Costa Rican Lophostoma brasiliense (Chiroptera: Phyllostomidae) JF - Mammalian Biology Y1 - 2008 A1 - York, Heather A. A1 - Foster, Paul F. A1 - Jones, M. F. A1 - Schwarz, Walter H. KW - Costa Rica KW - Lophostoma KW - Phyllostomidae KW - Reserva Ecológica Bijagual KW - roosting behavior KW - termite nest VL - 73 ER - TY - JOUR T1 - Reproductive strategies and natural history of the arboreal Neotropical vesper mouse, Nyctomys sumichrasti JF - Mammalia Y1 - 2013 A1 - Romero, Andrea A1 - Timm, Robert M. KW - Central America KW - embryo balance KW - litter size KW - Reserva Ecológica Bijagual KW - seasonality KW - sex ratios AB -

The vesper mouse, Nyctomys sumichrasti (Rodentia: Cricetidae), a poorly known, arboreal, nocturnal, rodent found in Central America, has been considered rare, and limited information is available about its biology, especially reproduction. We obtained vesper mice from several sites in Costa Rica and prepared them as scientific specimens with standard external measurements and reproductive data recorded. We expanded our dataset by including specimens from museum collections. Vesper mice have 1:1 sex ratios throughout their range. They reproduce year-round and litters may occur in rapid succession. Testis size is positively correlated with body mass; however, we could not determine the onset of sperm production. The onset of reproduction for females, based on mass, is variable but most females are parous by 60 g. Litter size is small with a mode of two, and embryos are not evenly distributed across the uterine horns. Vesper mice exhibit striking morphological differences in terms of tooth-wear and pelage patterns across their range. Much work is needed to fully appreciate N. sumichrasti, its role in tropical habitats, and its reproductive biology.

VL - 77 IS - 4 ER - TY - JOUR T1 - Stable-isotope Analysis of Diets of Short-tailed Fruit Bats (Chiroptera: Phyllostomidae: Carollia ) JF - Journal of Mammalogy Y1 - 2009 DO - 10.1644/08-MAMM-A-382R.1 A1 - York, Heather A A1 - Billings, Sharon A SP - 1469 EP - 1477 KW - Carollia KW - feces KW - frugivory KW - habitat use KW - insectivory KW - niche partitioning KW - Reserva Ecológica Bijagual KW - stable isotopes KW - trophic level AB -

The coexistence of multiple species of short-tailed fruit bats (Phyllostomidae: Carollia) is common throughout the range of the genus. Previous studies of fecal and stomach contents have documented differences in dietary breadth and in habitat use as mechanisms by which these species may partition dietary niches. By comparing values of ð15N and δ13C across species of Carollia from 17 sites in Central and South America, we show that co-occurring Carollia frequently differ in dietary breadth, foraging habitats, and level of insectivory. Values of δ15N, which tended to be enriched in C. castanea, depleted in C. perspicillata, and intermediate in C. brevicauda and C. sowelli, indicate trophic stratification. Values of δ13C followed the opposite trend, tending to be enriched in C. perspicillata and depleted in C. castanea, suggesting interspecific differences in breadth of the foraging area. Isotopic comparisons among Carollia, other bat species, and potential food items at 5 of our sites illustrate that populations of Carollia tend to be trophically intermediate between strictly phytophagous and strictly insectivorous organisms, and, contrary to the paucity of insect remains found in fecal samples, indicate that the consumption of insects by Carollia is more common and potentially more important than previously was thought.

VL - 90 IS - 6 JO - Journal of Mammalogy ER -