74 research outputs found

    Aquatic invertebrate communities in tank bromeliads: how well do classic ecological patterns apply?

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    Tank bromeliads (Bromeliaceae) often occur in high densities in the Neotropics and represent a key freshwater habitat in montane forests, housing quite complex invertebrate communities. We tested the extent to which there are species richness–altitude, richness–environment, richness–size, richness–habitat complexity and richness–isolation relationships for the aquatic invertebrate communities from 157 bromeliads in Cusuco National Park, Honduras. We found that invertebrate species richness and abundance correlated most strongly, and positively, with habitat size, which accounted for about a third of the variance in both. Apart from bromeliad size (equivalent of the species– area relationship), we found remarkably little evidence of classic biogeographic and ecological relationships with species richness in this system. Community composition correlated with altitude, bromeliad size and position, though less than 20% of the variation was accounted for by the tested variables. The turnover component of dissimilarity between the communities correlated with altitude, while the nestedness-resultant component was related to bromeliad size. The unexplained variance could reflect a large stochastic component in the system, associated with the ephemerality of the habitat patches (both the plants themselves and the fluctuations in their water content) and stochasticity due to the dispersal dynamics in the system. We conclude that there is a small contribution of classic biogeographic factors to the diversity and community composition of aquatic invertebrates communities in bromeliads. This may be due to the highly dynamic nature of this system, with small patch sizes and high emigration rates. The patterns may mostly be driven by factors affecting colonisation success

    Pools "on the rocks" : freshwater rock pools as model system in ecological and evolutionary research

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    Rock pools inarguably exhibit a number of characteristics which make them attractive as a model system in ecological and evolutionary research. They are usually small, pristine, clearly delineated and structurally simple systems that occur on a global scale. They facilitate the quantification of important population and community structuring processes which are often hard or impossible to quantify in larger more complex systems. Basic properties and spatial configuration of rock pools also closely resemble theoretical metapopulation and metacommunity models. Due to the simple morphometry of rock pool basins and the lack of any groundwater interactions, rock pool hydrologies are simple allowing to reliably reconstruct the disturbance regime against which patterns of variation in life histories, population genetics, species diversity and community structure can be interpreted.Sin lugar a dudas las pozas en rocas presentan numerosas características que las hacen atractivas para su uso como sistema modelo en la investigación evolutivo-ecológica. Normalmente son sistemas vírgenes de pequeño tamaño, estructuralmente sencillos y claramente delineados, que se encuentran a escala global. Permiten la cuantificación de importantes procesos estructuradores de poblaciones y comunidades que, a menudo, son muy difíciles o imposibles de cuantificar en sistemas mayores más complejos. Las propiedades básicas y la configuración espacial de las pozas en rocas también muestran una estrecha semejanza con los modelos teóricos de metapoblación y metacomunidad. Debido a la morfometría simple de las cubetas de estas pozas y a la carencia de interacciones con las aguas subterráneas, las hidrologías de estas pozas son de poca complejidad, lo que permite reconstruir con fiabilidad el régimen de perturbación determinante de los patrones de variación de los ciclos de vida de los organismos, de la genética de poblaciones, diversidad de especies y estructura de comunidades

    The value of eco-volunteer projects for biodiversity conservation - butterfly monitoring in Krka National Park (Croatia) with an updated checklist

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    The biogeographical importance of Dalmatia, bordered by the Dinaric Alps and the Adriatic Sea, is evident through the rich biodiversity of this region and its network of protected areas. One of those areas, Krka National Park (NP), supports a wide range of natural habitats, but rapidly increasing tourism puts high pressure on its ecosystems, despite its protected status. Accurate knowledge of species and their distributions within natural places such as Krka is essential to direct and prioritize future conservation efforts. As collecting biodiversity data is time and resource-intensive, alternative ways to obtain this information are needed. One possibility is monitoring based on eco-volunteering. From June to August of 2019, an Operation Wallacea/BIOTA scientific team surveyed a section of Krka NP and its surrounding boundaries, within the vicinity of the village of Puljane, to study its butterfly richness and abundance. Pollard walks and static count surveys were conducted with the help of eco-volunteers, testing the effectiveness of gathering field data through this approach. Overall, 57 butterfly species were found throughout the study, including four new records for Krka NP. Three further new species for the park were detected close to its boundaries and are also expected to occur within its borders. Here, we present an updated butterfly checklist for Krka NP, highlighting the positive impact of eco-volunteering initiatives and the importance of combined research efforts to study and protect the rich biodiversity and ecosystems of protected areas.info:eu-repo/semantics/publishedVersio

    Toward a Global Phylogeny of the “Living Fossil" Crustacean Order of the Notostraca

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    Tadpole shrimp (Crustacea, Notostraca) are iconic inhabitants of temporary aquatic habitats worldwide. Often cited as prime examples of evolutionary stasis, surviving representatives closely resemble fossils older than 200 mya, suggestive of an ancient origin. Despite significant interest in the group as ‘living fossils’ the taxonomy of surviving taxa is still under debate and both the phylogenetic relationships among different lineages and the timing of diversification remain unclear. We constructed a molecular phylogeny of the Notostraca using model based phylogenetic methods. Our analyses supported the monophyly of the two genera Triops and Lepidurus, although for Triops support was weak. Results also revealed high levels of cryptic diversity as well as a peculiar biogeographic link between Australia and North America presumably mediated by historic long distance dispersal. We concluded that, although some present day tadpole shrimp species closely resemble fossil specimens as old as 250 mya, no molecular support was found for an ancient (pre) Mesozoic radiation. Instead, living tadpole shrimp are most likely the result of a relatively recent radiation in the Cenozoic era and close resemblances between recent and fossil taxa are probably the result of the highly conserved general morphology in this group and of homoplasy

    Non-volant mammal inventory of Cusuco National Park, northwest Honduras: reporting the presence of Jaguar, Panthera onca (Linnaeus, 1758), and demonstrating the effects of zonal protection on mammalian abundance

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    Neotropical cloud forests are one of the most biodiverse yet threatened ecosystems with deforestation and hunting creating major problems. We report a non-volant mammal species inventory for Cusuco National Park, Honduras, spanning 2006–2016. Data were collected using 4 methods: tracks and signs, camera trapping, direct sightings and live trapping. Recorded species of conservation importance included Central American red brocket (Mazama temama (Kerr, 1792)), Baird’s tapir (Tapirus bairdii (Gill, 1865)), margay (Leopardus wiedii (Schinz, 1821)), and jaguar (Panthera onca (Linnaeus, 1758)); the latter recorded for the first time. Cusuco National Park is a site of strategic geographical importance within the Central American jaguar corridor. In total, 43 species were recorded from 26 families. We demonstrate the impact of zonal protection measures with higher mammal abundance recorded in the park’s highly protected core compared to the less protected buffer zone. We advise continued monitoring to provide robust time-series of population trends

    Dominant predators mediate the impact of habitat size on trophic structure in bromeliad invertebrate communities

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    Local habitat size has been shown to influence colonization and extinction processes of species in patchy environments. However, species differ in body size, mobility, and trophic level, and may not respond in the same way to habitat size. Thus far, we have a limited understanding of how habitat size influences the structure of multitrophic communities and to what extent the effects may be generalizable over a broad geographic range. Here, we used water-filled bromeliads of different sizes as a natural model system to examine the effects of habitat size on the trophic structure of their inhabiting invertebrate communities. We collected composition and biomass data from 651 bromeliad communities from eight sites across Central and South America differing in environmental conditions, species pools, and the presence of large-bodied odonate predators. We found that trophic structure in the communities changed dramatically with changes in habitat (bromeliad) size. Detritivore : resource ratios showed a consistent negative relationship with habitat size across sites. In contrast, changes in predator : detritivore (prey) ratios depended on the presence of odonates as dominant predators in the regional pool. At sites without odonates, predator : detritivore biomass ratios decreased with increasing habitat size. At sites with odonates, we found odonates to be more frequently present in large than in small bromeliads, and predator : detritivore biomass ratios increased with increasing habitat size to the point where some trophic pyramids became inverted. Our results show that the distribution of biomass amongst food-web levels depends strongly on habitat size, largely irrespective of geographic differences in environmental conditions or detritivore species compositions. However, the presence of large-bodied predators in the regional species pool may fundamentally alter this relationship between habitat size and trophic structure. We conclude that taking into account the response and multitrophic effects of dominant, mobile species may be critical when predicting changes in community structure along a habitat-size gradient.Fil: Petermann, Jana S.. Freie Universitat Berlin. Institute of Biology; AlemaniaFil: Farjalla, Vinicius F.. Universidade Federal do Rio de Janeiro; BrasilFil: Jocque, Merlijn. State University Of New Jersey; Estados UnidosFil: Kratina, Pavel. Queen Mary University Of London. School of Biological and Chemical Sciences; Reino UnidoFil: Macdonald, Andrew. University Of British Columbia; CanadáFil: Marino, Nicholas. Universidade Federal do Rio de Janeiro; BrasilFil: de Omena, Paula. Universidade Estadual de Campinas; BrasilFil: Piccoli, Gustavo. Universidade de Sao Paulo; BrasilFil: Richardson, Michael. Universidad de Puerto Rico; Puerto RicoFil: Richardson, Barbara. Universidad de Puerto Rico; Puerto RicoFil: Romero, Gustavo. Universidade Estadual de Campinas; BrasilFil: Videla, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinario de Biología Vegetal (p); Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Investigaciones Entomológicas de Córdoba; ArgentinaFil: Srivastava, Diane. University Of British Columbia; Canad

    Initiating a collaborative monitoring system to survey Maltese orchids

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    Orchids have always garnered the interest of enthusiastic amateurs and nonprofessional researchers as a charismatic species group and have become a flagship for Mediterranean flora. At the same time they are a decent indicator for biodiversity and environmental quality through their association with specific pollinators and mycorrhizal fungi. Historical records for orchids occurring in the Maltese Islands number some 30 different species, but there is little to no comprehensive data on their abundance and distribution.peer-reviewe

    A review of the ecological value of Cusuco National Park an urgent call forconservation action in a highly threatened Mesoamerican cloud forest

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    Cloud forests are amongst the most biologically unique, yet threatened, ecosystems in Mesoamerica. We summarize the ecological value and conservation status of a well-studied cloud forest site: Cusuco National Park (CNP), a 23,440 ha protected area in the Merendón mountains, northwest Honduras. We show CNP to have exceptional biodiversity; of 966 taxa identified to a species-level to date, 362 (37.5%) are Mesoamerican endemics, 67 are red-listed by the IUCN, and at least 49 are micro-endemics known only from the Merendón range. CNP also provides key ecosystem services including provision of drinking water and downstream flood mitigation, as well as carbon sequestration, with an estimated stock of 3.5 million megagrams of carbon in 2000. Despite its ecological importance, CNP faces multiple environmental threats and associated stresses, including deforestation (1,759 ha since 2000 equating to 7% of total forest area), poaching (7% loss of mammal relative abundance per year), amphibian declines due to chytridiomycosis (70% of species threatened or near-threatened), and climate change (a mean 2.6 °C increase in temperature and 112 mm decrease in rainfall by 2100). Despite conservation actions, including community ranger patrols, captive-breeding programmes, and ecotourism initiatives, environmental degradation of CNP continues. Further action is urgently required, including reinforcement and expansion of ranger programmes, greater stakeholder engagement, community education programmes, development of alternative livelihood projects, and legislative enforcement and prosecution. Without a thorough and rapid response to understand and mitigate illegal activities, the extirpation and extinction of species and the loss of vital ecosystem services are inevitable in the coming decades

    Modelling Hurricane Exposure and Wind Speed on a Mesoclimate Scale: A Case Study from Cusuco NP, Honduras

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    High energy weather events are often expected to play a substantial role in biotic community dynamics and large scale diversity patterns but their contribution is hard to prove. Currently, observations are limited to the documentation of accidental records after the passing of such events. A more comprehensive approach is synthesising weather events in a location over a long time period, ideally at a high spatial resolution and on a large geographic scale. We provide a detailed overview on how to generate hurricane exposure data at a meso-climate level for a specific region. As a case study we modelled landscape hurricane exposure in Cusuco National Park (CNP), Honduras with a resolution of 50 m×50 m patches. We calculated actual hurricane exposure vulnerability site scores (EVVS) through the combination of a wind pressure model, an exposure model that can incorporate simple wind dynamics within a 3-dimensional landscape and the integration of historical hurricanes data. The EVSS was calculated as a weighted function of sites exposure, hurricane frequency and maximum wind velocity. Eleven hurricanes were found to have affected CNP between 1995 and 2010. The highest EVSS's were predicted to be on South and South-East facing sites of the park. Ground validation demonstrated that the South-solution (i.e. the South wind inflow direction) explained most of the observed tree damage (90% of the observed tree damage in the field). Incorporating historical data to the model to calculate actual hurricane exposure values, instead of potential exposure values, increased the model fit by 50%
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