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Spatial and temporal patterns of bird species diversity in the Pantanal of Mato Grosso, Brazil: implications for conservation
Figueira, J. E. C.;Cintra, R.;Viana, L. R.;Yamashita, C.;
Brazilian Journal of Biology , 2006, DOI: 10.1590/S1519-69842006000300003
Abstract: analysis of a three-year bird survey in the pantanal of poconé revealed that most of the resident and seasonal birds are habitat generalists, using two or more habitats. in this study, previously sampled habitats were ranked in relation to species richness and stability (as measured by the ratio of seasonal to resident species). in all, nine habitats were grouped into three categories; results are as follows: 1) forests: more species-rich and more stable; 2) cerrado: intermediate levels; and 3) aquatic: less species-rich and less stable. the number of seasonal species remained relatively constant in forests throughout the year, while increasing in the other habitats during the dry season. the abundance of resident species seems to be related to species use of multiple habitats. although many species were found to be habitat generalists, we discuss possible consequences of habitat loss and other human impacts on efforts to conserve this important bird community.
A successful case of biological invasion: the fish Cichla piquiti, an Amazonian species introduced into the Pantanal, Brazil
Resende, EK.;Marques, DKS.;Ferreira, LKSG.;
Brazilian Journal of Biology , 2008, DOI: 10.1590/S1519-69842008000400014
Abstract: the "tucunaré", cichla piquiti, an exotic amazonian fish has become established along the left bank of the paraguay river in the pantanal. it was introduced by escaping from culture ponds in the upper piquiri river and spread downstream, along the lateral flooded areas of that river, continuing through the clear waters of the left bank of the paraguay river and reaching south as far as the paraguai mirim and negrinho rivers. adult spawners have been found in the region, meaning that it is a self-sustained population. reproduction occurs in the period of low waters. they were found feeding on fishes of lentic environments belonging to the families characidae, cichlidae and loricariidae. until the end of 2004, its distribution was restricted to the left bank of the paraguay river, but in march 2005, some specimens were found on the right bank, raising a question for the future: what will be the distribution area of the tucunaré in the pantanal? information about its dispersion is increasing: it is known to be in the tuiuiú lake, pantanal national park and in the bolivian pantanal, all of them on the right bank of the paraguay river. the hypothesis that the "tucunaré" could not cross turbid waters, such as in the paraguay river, was refuted by these recent findings. possibly, the tucunaré's capacity to lay more than one batch of eggs in a reproductive period, as well as its care of eggs and young, lead them to establish themselves successfully in new environments, as has been observed in the pantanal and other localities.
Cultural Keystone Species: Implications for Ecological Conservation and Restoration  [cached]
Ann Garibaldi,Nancy Turner
Ecology and Society , 2004,
Abstract: Ecologists have long recognized that some species, by virtue of the key roles they play in the overall structure and functioning of an ecosystem, are essential to its integrity; these are known as keystone species. Similarly, in human cultures everywhere, there are plants and animals that form the contextual underpinnings of a culture, as reflected in their fundamental roles in diet, as materials, or in medicine. In addition, these species often feature prominently in the language, ceremonies, and narratives of native peoples and can be considered cultural icons. Without these "cultural keystone species," the societies they support would be completely different. An obvious example is western red-cedar (Thuja plicata) for Northwest Coast cultures of North America. Often prominent elements of local ecosystems, cultural keystone species may be used and harvested in large quantities and intensively managed for quality and productivity. Given that biological conservation and ecological restoration embody human cultures as crucial components, one approach that may improve success in overall conservation or restoration efforts is to recognize and focus on cultural keystone species. In this paper, we explore the concept of cultural keystone species, describe similarities to and differences from ecological keystone species, present examples from First Nations cultures of British Columbia, and discuss the application of this concept in ecological restoration and conservation initiatives.
A conservation agenda for the Pantanal's biodiversity
Alho, CJR;Sabino, J;
Brazilian Journal of Biology , 2011, DOI: 10.1590/S1519-69842011000200012
Abstract: the pantanal's biodiversity constitutes a valuable natural resource, in economic, cultural, recreational, aesthetic, scientific and educational terms. the vegetation plus the seasonal productivity support a diverse and abundant fauna. many endangered species occur in the region, and waterfowl are exceptionally abundant during the dry season. losses of biodiversity and its associated natural habitats within the pantanal occur as a result of unsustainable land use. implementation of protected areas is only a part of the conservation strategy needed. we analyse biodiversity threats to the biome under seven major categories: 1) conversion of natural vegetation into pasture and agricultural crops, 2) destruction or degradation of habitat mainly due to wild fire, 3) overexploitation of species mainly by unsustainable fishing, 4) water pollution, 5) river flow modification with implantation of small hydroelectric plants, 6) unsustainable tourism, and 7) introduction of invasive exotic species.
Conservation and implications of eukaryote transcriptional regulatory regions across multiple species
Lin Wan, Dayong Li, Donglei Zhang, Xue Liu, Wenjiang J Fu, Lihuang Zhu, Minghua Deng, Fengzhu Sun, Minping Qian
BMC Genomics , 2008, DOI: 10.1186/1471-2164-9-623
Abstract: We constructed a hierarchical stochastic language (HSL) model for the identification of core TRRs in yeast based on regulatory cooperation among TRR elements. The HSL model trained based on yeast achieved comparable accuracy in predicting TRRs in other species, e.g., fruit fly, human, and rice, thus demonstrating the conservation of TRRs across species. The HSL model was also used to identify the TRRs of genes, such as p53 or OsALYL1, as well as microRNAs. In addition, the ENCODE regions were examined by HSL, and TRRs were found to pervasively locate in the genomes.Our findings indicate that 1) the HSL model can be used to accurately predict core TRRs of transcripts across species and 2) identified core TRRs by HSL are proper candidates for the further scrutiny of specific regulatory elements and mechanisms. Meanwhile, the regulatory activity taking place in the abundant numbers of ncRNAs might account for the ubiquitous presence of TRRs across the genome. In addition, we also found that the TRRs of protein coding genes and ncRNAs are similar in structure, with the latter being more conserved than the former.The identification of transcriptional regulatory elements that control the expression of each transcript is a fundamental and challenging problem in biology. Although tremendous progress has been made, both experimentally and computationally, the regulatory elements of genes are still not well understood, and only a handful of them have so far been experimentally verified [1]. The computational identification of regulatory elements is difficult for several reasons. First, genomic regulatory elements are usually short and degenerate [2]. Second, they are usually distributed across large genomic regions from the distant 5' upstream regions to the 3' downstream regions [3]. Meanwhile, ENCODE, a pilot project to identify all functional elements in the human genome sequence, has revealed that at least 93% of the human genome is transcribed in different cells and that
Germination in seed species ingested by opossums: implications for seed dispersal and forest conservation
Cáceres, Nilton Carlos;Monteiro-Filho, Emygdio Leite de Araújo;
Brazilian Archives of Biology and Technology , 2007, DOI: 10.1590/S1516-89132007000700002
Abstract: seed germination in plant species consumed by opossums, genus didelphis, was investigated in southern brazil, in order to improve knowledge of the strategies of zoochorous plants in the neotropics. seeds were obtained from opossum feces. thirteen of the most frequent species in the diet of local opossums were tested for germination rates and germination responses under different qualities (red/far red ratio) and different intensities of light. most seeds from feces germinated similarly to the control groups, except for seeds of rubus rosifolius, which appeared to depend on gut passage. other experiments revealed that most seeds in the opossums' diet were of pioneer species, with most germination occurring during favorable humid conditions in the rainy season. a few species showed negative photoblastism, or no dormancy pattern. small mammals are suggested as possible tools for area recuperation programs, through seed dispersal of many pioneer and some shade-tolerant plants, under suitable management.
Maintenance of Genetic Diversity in an Introduced Island Population of Guanacos after Seven Decades and Two Severe Demographic Bottlenecks: Implications for Camelid Conservation  [PDF]
Benito A. González, Pablo Orozco-terWengel, Rainer von Borries, Warren E. Johnson, William L. Franklin, Juan C. Marín
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0091714
Abstract: Fifteen guanacos were introduced to Staats Island in the Falklands/Malvinas archipelago from Patagonia in the 1930s. Twenty five years later, the population was culled from 300 to 10–20 individuals, but quickly rebounded to a population of almost 400 animals that today retain the genetic signature of the founding event and later bottleneck. The goals of this study were to (i) make a genetic assessment of this island population through comparisons with mainland populations and simulations, and (ii) assess the likely source-population of the introduced guanacos. Genetic variation was estimated from 513 bp of mitochondrial DNA sequence and 15 microsatellite loci among 154 guanacos collected from eight localities, including the adjacent mainland and the islands of Tierra del Fuego and Staats Island. Of the 23 haplotypes observed among our samples, the Staats Island population only contained three haplotypes, all of which were shared with the coastal Monte Leon population in southern Patagonia. Mitochondrial DNA and microsatellite variations on Staats Island were comparable to most mainland populations and greater than those observed on Tierra del Fuego. Patterns of genetic structure suggest that the Staats Island guanaco population was founded with animals from southern Patagonia (as opposed to northern Patagonia or Tierra del Fuego), but that effective reductions in population size lasted only a few generations and that surviving animals were a random sample of the pre-bottleneck genetic variation.
Species Richness and Community Structure on a High Latitude Reef: Implications for Conservation and Management  [PDF]
Alison M. Jones,Ray Berkelmans,Wayne Houston
Diversity , 2011, DOI: 10.3390/d3030329
Abstract: In spite of the wealth of research on the Great Barrier Reef, few detailed biodiversity assessments of its inshore coral communities have been conducted. Effective conservation and management of marine ecosystems begins with fine-scale biophysical assessments focused on diversity and the architectural species that build the structural framework of the reef. In this study, we investigate key coral diversity and environmental attributes of an inshore reef system surrounding the Keppel Bay Islands near Rockhampton in Central Queensland, Australia, and assess their implications for conservation and management. The Keppels has much higher coral diversity than previously found. The average species richness for the 19 study sites was ~40 with representatives from 68% of the ~244 species previously described for the southern Great Barrier Reef. Using scleractinian coral species richness, taxonomic distinctiveness and coral cover as the main criteria, we found that five out of 19 sites had particularly high conservation value. A further site was also considered to be of relatively high value. Corals at this site were taxonomically distinct from the others (representatives of two families were found here but not at other sites) and a wide range of functionally diverse taxa were present. This site was associated with more stressful conditions such as high temperatures and turbidity. Highly diverse coral communities or biodiversity ‘hotspots’ and taxonomically distinct reefs may act as insurance policies for climatic disturbance, much like Noah’s Arks for reefs. While improving water quality and limiting anthropogenic impacts are clearly important management initiatives to improve the long-term outlook for inshore reefs, identifying, mapping and protecting these coastal ‘refugia’ may be the key for ensuring their regeneration against catastrophic climatic disturbance in the meantime.
Ecology and Fish Biodiversity of Man-Made Lakes of Southern Benin (West Africa): Implications for Species Conservation and Fisheries Management  [PDF]
Houehanou M. A. G. Gbaguidi, Alphonse Adite, Edmond Sossoukpe
Journal of Environmental Protection (JEP) , 2016, DOI: 10.4236/jep.2016.76079
Abstract:

Man-made lakes are alternative and potential habitats for biodiversity conservation, fisheries and extensive aquaculture. We investigated the ecology and the fish community structure of two (2) sand-dragged man-made lakes, Lake Ahozon and Lake Bewacodji of Southern Benin, with implications for species conservation, fisheries management and aquaculture valorization. From August 2014 to July 2015, habitats conditions were evaluated and fishes were sampled monthly with seine, cast net, experimental gill net and hooks in the open water and aquatic vegetation habitats of both lakes. Overall, the water quality of Lake Ahozon was globally favorable for the growth and the survival of the fish resources whereas Lake Bewacodji exhibited a poor water quality indicated mainly by an acid pH (mean: 6.32 ± 0.58) and low dissolved oxygen concentrations (mean: 3.52 ± 1.25 mg/l) caused by dense floating plants, Nymphea sp mainly and huge daily dumping of domestic wastes. The study revealed low species richness, d = 5.89 and d = 3.87, and low species diversity, H’ = 0.76 and H’ = 0.48 for Lakes Ahozon and Bewacodji, respectively, with Lake Ahozon more diverse than Lake Bewacodji. The fish community of Lake Ahozon comprised six (6) species, 3 cichlids Sarotherodon galilaeus, Oreochromis niloticus and Tilapia guineensis, the silver catfish, Chrysichthys nigrodigitatus (Claroteidae), the African bonytongue, Heterotis niloticus (Osteoglossidae), and the African catfish, Clarias gariepinus (Clariidae). Numerically, S. galilaeus dominated Lake Ahozon and made 85.21% of the sample. In Lake Bewacodji, the fish composition comprised four (4) species, Sarotherodon galilaeus multifasciatus, the dominant species making numerically 91.58% of the total sample, T. guineensis, C. gariepinus and C. nigrodigitatus. With regard to trophic?structure, the fish assemblages of both lakes were numerically dominated by planktinovores/ detritivores, mainly S. galilaeus, O. niloticus, T. guineensis and C. nigrodigitatus making together 99.46% of Lake Ahozon fish community, and S. galilaeus multifasciatus, T. guineensis and C. nigrodigitatus?accounting together for about 98.59% of Lake Bewacodji. In Lake Ahozon, standard length (SL) frequencies histograms showed an unimodal size distribution for

Host-Parasite Relationship of Ticks (Acari: Ixodidae and Argasidae) and Feral Pigs (Sus scrofa) in the Nhecolandia Region of the Pantanal Wetlands in Mato Grosso do Sul  [PDF]
P. H. D. Can?ado,J. L. H. Faccini,H. M. Herrera,L. E. R. Tavares,G. M. Mour?o,E. M. Piranda,R. C. S. Paes,C. C. D. U. Ribeiro,T. C. Borghesan,A. K. Piacenti,M. A. Kinas,C. C. Santos,T. M. Ono,F. Paiva
ISRN Parasitology , 2013, DOI: 10.5402/2013/610262
Abstract: Feral pigs (S. scrofa) were introduced to the Pantanal region around 200 years ago and the population appears to be in expansion. Its eradication is considered to be impossible. The population of feral pigs in the Pantanal wetlands is currently estimated at one million. Two scientific excursions were organized. The first was conducted during the dry season, when 21 feral pigs were captured and the second was during the wet season, when 23 feral pigs were captured. Ticks were collected and the oviposition and hatching process were studied to confirm the biological success of each tick species. Three tick species were found to be feeding on feral pigs: Amblyomma cajennense, A. parvum, and Ornithodoros rostratus. During the dry season, 178 adult A. cajennense were collected, contrasting with 127 A. cajennense specimens in the wet season. This suggests that the seasonality of these ticks in the Brazilian Pantanal wetlands could be different from other regions. The results indicate that A. parvum and A. cajennense are biologically successful parasites in relation to feral pigs. A. cajennense appears to have adapted to this tick-host relationship, as well as the areas where feral pigs are abundant, and could play a role in the amplification of this tick population. 1. Introduction Ticks have coevolved with various wild animal hosts which are reservoir hosts for pathogens such as fungi, bacteria, viruses, rickettsiae, and protozoan which can be transmitted to domestic mammals and humans [1–3]. Ticks that feed on feral or domestic pigs (Sus scrofa) and their tick-borne diseases have been previously studied worldwide [4–7]. The most common tick species reported in association with domestic pigs in Brazil is Amblyomma cajennense (Fabricius, 1787), an eclectic tick that has a broad range of hosts and widespread distribution [8–10]. In Brazil, this hard tick is an important vector of Rickettsia rickettsii to humans [11]. A second genus reported in association with Brazilian pigs is the genus Ornithodoros, which has two species: O. rostratus and O. brasiliensis. Both of these species have also been reported in association with wild native pigs (Tayassu sp.) [8, 9]. The Pantanal ecosystem is considered to be one of the most well-preserved biomes in Brazil and was added to the UNESCO World Heritage List in 2000. The Brazilian Pantanal has been described as a “biological hotspot” for conservation and one of the richest and the most diverse ecosystems in the world. In this biome, wild animals and their parasites engage in complex and dynamic interactions. However, this
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