scholarly journals Abundance, distribution and conservation of Rio Branco Antbird Cercomacra carbonaria and Hoary-throated Spinetail Synallaxis kollari

2007 ◽  
Vol 17 (3) ◽  
pp. 245-257 ◽  
Author(s):  
Mariana M. Vale ◽  
J. Bruce Bell ◽  
Maria Alice S. Alves ◽  
Stuart L. Pimm
Keyword(s):  
Population Density ◽  
Population Size ◽  
Threatened Species ◽  
Total Population ◽  
Local Population ◽  
Iucn Red List ◽  
Red List ◽  
Conservation Units ◽  
Total Population Size ◽  
Species Lists

AbstractCercomacra carbonaria and Synallaxis kollari are passerine birds endemic to the gallery forests of Roraima state in northernmost Brazil and adjacent Guyana. The IUCN Red List of Threatened Species lists both as Vulnerable but they have been removed from Brazil's list of threatened species because of data deficiency. They are poorly known, reflecting both Roraima state's distance from Brazil's main population centres and the inaccessibility of their habitat. In 2004 and 2005, we conducted bird surveys along the major rivers that provided previous sightings, and expanded records from only a handful to several dozens. We found C. carbonaria at 29% of the points surveyed, and estimated its local population density at approximately 80 individuals km−2 and total population size to exceed 15,000 individuals. The species has 723 km2 of available habitat, 8% of which is inside conservation units. We found S. kollari at 44% of the points surveyed, and estimated its local population density as approximately 60 individuals km−2, with an estimated total population size exceeding 5,000 individuals. It has 206 km2 of available habitat, none of which is inside conservation units. We recommend that C. carbonaria be down-listed on the IUCN Red List to the Near Threatened category, and that S. kollari be listed as Endangered. Both species live in areas vulnerable to habitat loss. We also recommend that both species re-enter the Brazilian list of threatened species and highlight the importance of indigenous reserves to their conservation.ResumoCercomacra carbonaria e Synallaxis kollari são aves passeriformes das matas de galeria do Estado de Roraima em sua parte mais ao norte do Brasil e da Guiana adjacente. Ambas as espécies são catalogadas como “Vulneráveis” pela lista vermelha de espécies ameaçadas da IUCN, mas foram excluídas da lista de espécies ameaçadas do Brasil devido è insuficiência de dados. Estas espécies são pouco conhecidas, refletindo tanto a distância do Estado de Roraima dos principais centros urbanos quanto a inacessibilidade do seu hábitat. Em 2004 e 2005, realizamos censos de aves anteriormente avistadas ao longo de rios maiores, aumentando assim os registros de apenas alguns poucos números para diversas dezenas. Encontramos C. carbonaria em 29% dos pontos amostrados e estimamos sua densidade local em ∼80 indivíduos km−2 e o tamanho populacional total em mais de 15.000 indivíduos. A espécie possui 723 km2 de habitat disponível, 8% do qual está incluído em unidades de conservação. Encontramos S. kollari em 44% dos pontos amostrados e estimamos sua densidade populacional local em ∼60 indivíduos km−2, com uma estimativa de tamanho populacional total em mais de 5,000 indivíduos. Esta espécie tem 206 km2 de habitat disponível, nenhum dos quais incluído em unidades de conservação. Recomendamos que C. carbonaria seja rebaixada para a categoria ‘Quase Ameaçada’ e S. kollari categorizada como ‘Ameaçada’ na lista vermelha da IUCN. Ambas as espécies vivem em áreas vulneráveis em relação è perda de seu hábitat. Recomendamos, também, que ambas as espécies sejam re-incluídas na lista de espécies ameaçadas do Brasil, destacando a importância das reservas indígenas para a sua conservação.

scholarly journals Reintroduction of illegally extracted Melocactus violaceus (Cactaceae) in Brazil

Oryx ◽  
2020 ◽  
pp. 1-4
Author(s):  
Haissa de Abreu Caitano ◽  
Valquíria Ferreira Dutra ◽  
Rodrigo Theófilo Valadares ◽  
Luana Silva Braucks Calazans
Keyword(s):  
Environmental Monitoring ◽  
Threatened Species ◽  
Natural Habitat ◽  
Iucn Red List ◽  
Red List ◽  
Natural Area ◽  
Conservation Units ◽  
Threatened Plant ◽  
Plant Families ◽  
Espirito Santo

Abstract Cactaceae is one of the most threatened plant families, in part as a result of the illegal extraction of plants for ornamental use. However, reports of the seizure and reintroduction of cacti are scarce and do not include species of Melocactus, the genus of Cactaceae in Brazil that has the highest number of threatened species. The coroa-de-frade Melocactus violaceus is endemic to Brazil and categorized as Vulnerable on the IUCN Red List. We report the seizure of 37 individuals of coroa-de-frade extracted illegally from their natural habitat, the results of their reintroduction to Paulo César Vinha State Park, in Espírito Santo state, Brazil, and provide information for environmental monitoring agencies regarding how to proceed in seizure cases, with the goal of minimizing the impacts of this illegal practice on the species. After seizure, 25 individuals were cultivated in a greenhouse and 12 were reintroduced in restinga, the natural area of occurrence of the species. After 6 months, survival was 76% for those individuals cultivated in the greenhouse and 84% for those planted in restinga, showing that rapid reintroduction of species with ornamental appeal, preferentially in their natural habitat, can reduce the impacts of illegal extraction. This reintroduction protocol can be used by managers of conservation units, contributing to the maintenance of threatened cactus species in their natural habitat.

A downlist is not a demotion: Red List status and reality

Oryx ◽  
2017 ◽  
Vol 51 (4) ◽  
pp. 605-609 ◽  
Author(s):  
David P. Mallon ◽  
Rodney M. Jackson
Keyword(s):  
Population Size ◽  
Giant Panda ◽  
Total Population ◽  
Extinction Risk ◽  
Conservation Status ◽  
Field Research ◽  
Iucn Red List ◽  
Red List ◽  
Ailuropoda Melanoleuca ◽  
Snow Leopard

AbstractAssessments of biodiversity status are needed to track trends, and the IUCN Red List has become the accepted global standard for documenting the extinction risk of species. Obtaining robust data on population size is an essential component of any assessment of a species’ status, including assessments for the IUCN Red List. Obtaining such estimates is complicated by methodological and logistical issues, which are more pronounced in the case of cryptic species, such as the snow leopardPanthera uncia. Estimates of the total population size of this species have, to date, been based on little more than guesstimates, but a comprehensive summary of recent field research indicates that the conservation status of the snow leopard may be less dire than previously thought. A revised categorization, from Endangered to Vulnerable, on the IUCN Red List was proposed but met some opposition, as did a recent, similar recategorization of the giant pandaAiluropoda melanoleuca. Possible factors motivating such attitudes are discussed. Downlisting on the IUCN Red List indicates that the species concerned is further from extinction, and is always to be welcomed, whether resulting from successful conservation intervention or improved knowledge of status and trends. Celebrating success is important to reinforce the message that conservation works, and to incentivize donors.

scholarly journals Conservation possibilities of Isophya costata (Orthoptera: Tettigoniidae: Phaneropterinae) based on frequency, population size, and habitats

2021 ◽  
Vol 30 (1) ◽  
pp. 35-41
Author(s):  
Zoltán Kenyeres ◽  
Norbert Bauer
Keyword(s):  
Data Collection ◽  
Population Size ◽  
Threatened Species ◽  
Natura 2000 ◽  
Iucn Red List ◽  
Red List ◽  
Dicotyledonous Plants ◽  
Species Area ◽  
Different Origin ◽  
Bush Cricket

Isophya costata Brunner von Wattenwyl, 1878, commonly called the Keeled Plump Bush-cricket, is an endemic Natura 2000 species in the Carpathian Basin and is included in the IUCN Red List of Threatened species. We used extensive data collection from Hungary retrieved between 2004 and 2019 from 700 sampling sites spread over an area of 12,700 km2 to examine the occurrence of the species in different regions in grasslands of similar structure but different origin, naturalness, and character. The results confirmed that I. costata currently occurs with the highest number of populations and highest density in regularly mowed, mesophilic hayfields rich in dicotyledonous plants (Arrhenatheretalia). The species also appears in smaller numbers in grasslands adjacent to hayfields, such as wetland meadows (Molinion coeruleae), marsh meadows (Deschampsion caespitosae, Alopecurenion pratensis), and edge habitats dominated by herbaceous plants. However, the results show that the extension of these habitats has a negatively significant correlation with both the occurrence of the species and its density. Isophya costata occurs in steppe meadows much less frequently than in mesophilic hayfields. The species is endemic to the Pannonian Steppe, and the key to their conservation is by maintaining stocks of hayfields in the species’ area of distribution. According to this study, overseeding of mowed grasslands leads to the decline of the species. To preserve I. costata, it is necessary to eliminate trampling in its areas of occurrence (prohibition of grazing) and encourage late-season mowing adapted to the phenology of the species (not as early as mid-July) or, if this is not feasible, mosaic-type treatment leaving unmown patches (e.g., 1/3 of the plot).

scholarly journals Large and medium-sized mammals of Carajás National Forest, Pará state, Brazil

Check List ◽  
2014 ◽  
Vol 10 (1) ◽  
pp. 1 ◽  
Author(s):  
Andréa Siqueira Carvalho ◽  
Frederico Drummond Martins ◽  
Francilma Mendes Dutra ◽  
Donald Gettinger ◽  
Fernanda Martins-Hatano ◽  
...  
Keyword(s):  
Threatened Species ◽  
Iucn Red List ◽  
Red List ◽  
The State ◽  
Camera Traps ◽  
National Forest ◽  
Conservation Units ◽  
Amazonian Region ◽  
Mineral Reserves ◽  
Brazilian Biodiversity

The Carajás National Forest is located in the Amazonian region, Pará State, Brazil and is part of a mosaic of conservation units comprising over one million hectares. This region has been explored for its mineral reserves, but knowledge of the distribution of animals and plants is lacking. The objective of this paper is to provide a list of the medium and large-sized mammals recorded from the Carajás NF. We used four methods to record mammals: linear transects, camera traps, records of road-killed animals, and opportunistic observations. We recorded 45 species distributed in nine taxonomic orders, eight of them currently on the Brazilian list of threatened species and seven in the IUCN red list. The area has high mammalian diversity and holds 56% of the threatened species known for the State, confirming that the study area is correctly categorized as Extremely High Priority for the conservation of Brazilian biodiversity.

scholarly journals Giant otter Pteronura brasiliensis density and abundance in Llanos Orientales de Colombia in the Orinoco basin

Oryx ◽  
2020 ◽  
pp. 1-4
Author(s):  
Germán Garrote ◽  
Beyker Castañeda ◽  
Jose Manuel Escobar ◽  
Laura Pérez ◽  
Brayan Marín ◽  
...  
Keyword(s):  
South America ◽  
Population Size ◽  
20Th Century ◽  
Conservation Status ◽  
Species Conservation ◽  
Iucn Red List ◽  
Red List ◽  
Recreational Fishing ◽  
Pteronura Brasiliensis ◽  
Direct Counts

Abstract The giant otter Pteronura brasiliensis, categorized as Endangered on the IUCN Red List, was once widely distributed throughout South America. By the middle of the 20th century the giant otter had become locally extinct along the main rivers of the Orinoco basin. Although some populations seem to have recovered, the paucity of information available does not permit a full evaluation of the species' conservation status. The objective of this study was to estimate the abundance and density of the giant otter population along the Orinoco river in the municipality of Puerto Carreño, Vichada, Colombia, where there is important commercial and recreational fishing. Thirty-nine linear km were surveyed, repeatedly, with a total of 315 km of surveys. Population size was estimated by direct counts of individuals. All individuals detected were photographed and identified individually from their throat pelage patterns. In total, 30 otters were identified, giving a minimum density of 0.77 individuals per km, one of the highest reported for the species in Colombia. Given the high density in this well-developed area, our results highlight the importance of this population for the conservation of the species.

scholarly journals Conservation Status of Marine Biodiversity in Oceania: An Analysis of Marine Species on the IUCN Red List of Threatened Species

2011 ◽  
Vol 2011 ◽  
pp. 1-14 ◽  
Author(s):  
Beth A. Polidoro ◽  
Cristiane T. Elfes ◽  
Jonnell C. Sanciangco ◽  
Helen Pippard ◽  
Kent E. Carpenter
Keyword(s):  
Threatened Species ◽  
Environmental Changes ◽  
Extinction Risk ◽  
Conservation Status ◽  
Marine Species ◽  
Iucn Red List ◽  
Red List ◽  
Marine Biodiversity ◽  
Conservation Priorities ◽  
Conservation Action

Given the economic and cultural dependence on the marine environment in Oceania and a rapidly expanding human population, many marine species populations are in decline and may be vulnerable to extinction from a number of local and regional threats. IUCN Red List assessments, a widely used system for quantifying threats to species and assessing species extinction risk, have been completed for 1190 marine species in Oceania to date, including all known species of corals, mangroves, seagrasses, sea snakes, marine mammals, sea birds, sea turtles, sharks, and rays present in Oceania, plus all species in five important perciform fish groups. Many of the species in these groups are threatened by the modification or destruction of coastal habitats, overfishing from direct or indirect exploitation, pollution, and other ecological or environmental changes associated with climate change. Spatial analyses of threatened species highlight priority areas for both site- and species-specific conservation action. Although increased knowledge and use of newly available IUCN Red List assessments for marine species can greatly improve conservation priorities for marine species in Oceania, many important fish groups are still in urgent need of assessment.

Adjustment of fecundity and sex ratio in response to social environments in a haplodiploid mite

2022 ◽  
Author(s):  
Nuwan Weerawansha ◽  
Qiao Wang ◽  
Xiong Zhao He
Keyword(s):  
Population Density ◽  
Sex Ratio ◽  
Population Size ◽  
Local Population ◽  
Female Offspring ◽  
Social Environments ◽  
Positive Interaction ◽  
Offspring Sex Ratio ◽  
Offspring Sex ◽  
Large Populations

Animals can adjust reproductive strategies in favour of corporation or competition in response to local population size and density, the two key factors of social environments. However, previous studies usually focus on either population size or density but ignore their interactions. Using a haplodiploid spider mite, Tetranychus ludeni Zacher, we carried out a factorial experiment in the laboratory to examine how ovipositing females adjust their fecundity and offspring sex ratio during their early reproductive life under various population size and density. We reveal that females laid significantly more eggs with increasing population size and significantly fewer eggs with increasing population density. This suggests that large populations favour cooperation between individuals and dense populations increase competition. We demonstrate a significant negative interaction of population size and density that resulted in significantly fewer eggs laid in the large and dense populations. Furthermore, we show that females significantly skewed the offspring sex ratio towards female-biased in small populations to reduce the local mate competition among their sons. However, population density incurred no significant impact on offspring sex ratio, while the significant positive interaction of population size and density significantly increased the proportion of female offspring in the large and dense populations, which will minimise food or space competition as females usually disperse after mating at crowded conditions. These results also suggest that population density affecting sex allocation in T. ludeni is intercorrelated with population size. This study provides evidence that animals can manipulate their reproductive output and adjust offspring sex ratio in response to various social environments, and the interactions of different socio-environmental factors may play significant roles.

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