Ludmilla Aguiar | Universidade de Brasília - UnB (original) (raw)

Papers by Ludmilla Aguiar

Restingas are coastal ecosystems associated with the Atlantic Forest. They are threatened by habi... more Restingas are coastal ecosystems associated with the Atlantic Forest. They are threatened by habitat degradation and forest fragmentation due to intense human occupation. Many restingas have coastal lagoons formed by bay sedimentation of bays, the presence of river estuaries, or emerging groundwater. The distance between lagoons and the ocean influences the biotic community in them. This study aimed to compare the diversity (composition, abundance and richness) of bat communities associated with three lagoons within the Paulo Cesar Vinha State Park, Espírito Santo state. Two lagoons ('Feia' and 'Vermelha' lagoons) are 2 km away from the ocean, while the third ('Caraís' lagoon) is just a few meters distant from the ocean. Species composition did not differ among the lagoons. Abundance of Carollia perspicillata and Glossophaga soricina was higher in the 'Caraís' lagoon. Abundance of Artibeus lituratus and Platyrrhinus lineatus was higher in the 'Vermelha' lagoon. Species with higher abundance in the 'Vermelha' are usually associated with urban and disturbed environments. 'Vermelha' lagoon is closer to human settlements and this could be a major driver of bat species abundance associated with this lagoon instead of distance from the ocean. These results may be used to guide conservations efforts in the restingas or habitats associated with restingas.

Mammalia, May 12, 2023

Bats provide essential ecosystem services and some are cave dependent. Caves favour the associati... more Bats provide essential ecosystem services and some are cave dependent. Caves favour the association of bats with ectoparasite Diptera, however, they are poorly sampled in the Amazon biome. Here we present the first description of a community of bats and bat flies from the largest sandstone cave in Brazil, the Planaltina cave, located in the municipality of Brasil Novo, state of Pará. Diptera were removed from captured bats and taken to the laboratory for identification. From nine species of bats belonging to four families we recorded 17 species of Diptera, 13 were monoxenous. A possible explanation for the monoxenous parasites collected is that flies have poor survival in unusual hosts. These results are an indicator that the Streblid species are host-specific since even if the hosts take refuge in the same cave, they will not share their parasites. Therefore, the present study provides important information on the parasite-host dynamics in a cave, thus highlighting the importance of cave as are essential shelters for bat species and, despite reported cases of cohabitation, mixed colonies are unlikely to form.

Journal of Applied Ecology, Mar 9, 2011

1. Species richness is a state variable of some interest in monitoring programmes but raw species... more 1. Species richness is a state variable of some interest in monitoring programmes but raw species counts are often biased due to imperfect species detectability. Therefore, monitoring programmes should quantify detectability for target taxa to assess whether it varies over temporal or spatial scales. We assessed the potential for tropical bat monitoring programmes to reliably estimate trends in species richness. 2. Using data from 25 bat assemblages from the Old and New World tropics, we estimated detectability for all species in an assemblage (mean proportion of species detected per sampling plot) and for individual species (species-specific detectability). We further assessed how these estimates of detectability were affected by external sources of variation relating to time, space, survey effort and biological traits. 3. The mean proportion of species detected across 96 sampling plots was estimated at 0AE76 (range 0AE57-1AE00) and was significantly greater for phytophagous than for animalivorous species.

One of the most widely used organisms division is that of beneficial and adverse (or pest) organi... more One of the most widely used organisms division is that of beneficial and adverse (or pest) organisms (BROWN et al. 2001). In agriculture, pests include those that feed on plants parts, either above or below-ground, during a particular phase of their life cycle, leading to potentially important decreases in plant production (BROWN et al. 2001). Insectivorous bats are major predators of nocturnal insects and have the potential to act as biological pest control agents in farmlands (LEELAPAIBUL et al. 2005). Myotis nigricans (Schinz, 1821) and Eptesicus furinalis (d'Orbigny, 1847) are considered to be insectivorous species, feeding typically on small invertebrates (AGUIRRE et al. 2003). They are small bats (3-8 g) belonging to the Vespertilionidae family, and both are widely distributed over the Neotropical Region. Myotis nigricans is found from Nayarit and Taumalipas (Mexico) to Peru, Bolivia, north Argentina, Paraguay and Brazil, and Eptesicus furinalis from north Argentina, Paraguay, Bolivia, Brazil, and the Guyanas east to Peru and north to Jalisco and Taumalipas (Mexico) (SIMMONS 2005). Both species are sympatric over most of their range. Knowledge of food habits enables the identification of agricultural pests consumed by bats (WHITAKER 1995). Besides that, insectivorous bats are susceptible to the accumulation of toxins such as pesticides because of their high trophic rank and longevity (CLAWSON & CLARK 1989). So, knowledge of bats food habitats is also useful in identifying potential sources of toxins (CLAWSON & CLARK 1989

Bioacoustics-the International Journal of Animal Sound and Its Recording, Apr 1, 2022

The AGCV is a sustainable use protected area (equivalent to the IUCN management category VI), bei... more The AGCV is a sustainable use protected area (equivalent to the IUCN management category VI), being created in 1986 with 25,000 ha in the Southern of Brasília city (15 o 55' Lat S-47 o 52' Long W). The dominant natural vegetation in AGCV is the cerrado sensu stricto, with the presence of seasonally flooded grassland, campo cerrado, and tall savanna (cerradão). The second studied area is the Brasilia National Park (PNB) (15 o 40'Lat S-47 o 59' Long W), a strictly protected area corresponding to the IUCN Category II. The PNB was created in 1961 with 60,000 ha and currently has 42,335 ha. Its vegetation is characterized by the predominance of cerrado sensu stricto phytophysiognomy, gallery forest (along the streams), and grasslands with sparce cerrado trees. The third area is the Chapada dos Veadeiros National Park (PNCV) (14 o 06' Lat S-47 o 43' Long W), equivalent to the IUCN Category II). The Park was created in 1961 with 620,000 ha and now has 240,586 ha, with predominant vegetation of montane savanna, riparian forests, flooded forest with buritis palms (Mauritia flexuosa), and grasslands.

Perspectives in Ecology and Conservation

Protected areas (PAs) are a widely recognized tool for biodiversity and ecosystem conservation. H... more Protected areas (PAs) are a widely recognized tool for biodiversity and ecosystem conservation. However, megadiverse countries struggle to manage, maintain, and expand PAs as they face mounting human pressures. The Brazilian Cerrado biome (a biodiversity hotspot) is experiencing increasing land-use changes paired with a loss of natural vegetation, and only 3.2% of its land area is under strict protections. The Brazilian Long-Term Ecological Research Program (LTER) was created in 1997 to monitor long-term changes in protected and non-protected areas in Brazilian biomes. The Environmental Protected Area of the Gama and Cabeça de Veado (AGCV) watersheds in Central Brazil's core distribution of the Cerrado (Brasília, Federal District), was one of the first sites to participate in the Brazilian LTER. The main goal of the AGCV-LTER site is to monitor long-term changes and ecological processes in aquatic and terrestrial ecosystems in PAs that are surrounded by landscapes facing extreme ecosystem shifts. Over 22 years, we investigated the effects of drivers such as fire, noise and light pollution, eutrophication, and biological invasions on aquatic (invertebrates and water quality) and terrestrial ecosystems (vegetation, vertebrates, and invertebrates). The results indicate that even within a PA, changes in the surrounding landscape affects biodiversity and ecosystem functions, revealing the essential nature of continuous monitoring for biodiversity conservation.

Acta Chiropterologica, Aug 18, 2022

O Bioma Cerrado tem destaque nos cenários nacional e internacional em virtude de sua dimensão, ce... more O Bioma Cerrado tem destaque nos cenários nacional e internacional em virtude de sua dimensão, cerca de 24% do território brasileiro, de sua expressiva riqueza biológica estimada em cerca de 320 mil espécies vegetais, animais e de microrganismos, além da expressiva produção agropecuária. No entanto, nas últimas décadas, os recursos naturais têm sido tratados de forma fracionada, como se eles não fossem componentes de um sistema dinâmico. Essa visão cartesiana tem trazido prejuízos consideráveis ao meio ambiente e até mesmo à produção agropecuária por causa do ataque de pragas e doenças, escassez de água, perda de biodiversidade e expansão dos processos de erosão do solo. Trabalhar de forma sistêmica e desenvolver tecnologias menos agressivas ao meio ambiente contribui para a conservação e a utilização planejada dos recursos, constituindo o desafio atual da Embrapa Cerrados. Nesse sentido, este livro tem como objetivo apresentar os avanços da Embrapa Cerrados no desenvolvimento de tecnologias compatíveis com os cenários atuais e futuro, entendendo que a conservação dos recursos naturais condiciona o desenvolvimento econômico, o tecnológico e o social de uma nação.bitstream/item/224037/1/CERRADO-Desafios-oportunidas.pd

Frontiers in Ecology and Evolution

Ecosystem services (ES) are essential for human society worldwide. ES originate from ecological p... more Ecosystem services (ES) are essential for human society worldwide. ES originate from ecological processes commonly occurring in well-preserved regions. Bats play an essential role in providing such services, primarily insect suppression, plant pollination, and seed dispersal. Human activities have affected Earth’s systems, compromising species and ecosystems and, consequently, the ES provision. Brazil is a country with many bat species but is also one of the world’s leaders in deforestation. Here we aimed to identify regions with high potential for bats ecosystem services provision, assuming that the predicted presence of the species represents the existence of the services. First, we used a Maximum Entropy algorithm to model the distribution of 128 bat species, which correspond to 71% of the Brazilian species. We classify all species into 10 different groups, which resulted from a combination of three body sizes and four predominant trophic guilds (i.e., frugivores, insectivores, n...

Mastozoología Neotropical, 2021

We study the following problem: given an integer k ≥ 3 and a simple graph G, sample a connected i... more We study the following problem: given an integer k ≥ 3 and a simple graph G, sample a connected induced k-node subgraph of G uniformly at random. This is a fundamental graph mining primitive with applications in social network analysis, bioinformatics, and more. Surprisingly, no efficient algorithm is known for uniform sampling; the only somewhat efficient algorithms available yield samples that are only approximately uniform, with running times that are unclear or suboptimal. In this work we provide: (i) a near-optimal mixing time bound for a well-known random walk technique, (ii) the first efficient algorithm for truly uniform graphlet sampling, and (iii) the first sublinear-time algorithm for ε-uniform graphlet sampling.

Chiroptera Neotropical, 2014

O Rio de Janeiro foi o quarto Estado brasileiro a criar a sua lista estadual de especies de anima... more O Rio de Janeiro foi o quarto Estado brasileiro a criar a sua lista estadual de especies de animais ameacados de extincao e o terceiro a usar as categorias de status da IUCN (IUCN 1994). O Rio de Janeiro, a exemplo do estado de Sao Paulo, adotou a mesma metodologia criada para a definicao do status de ameaca dos morcegos brasileiros.

Perspectives in Ecology and Conservation, 2021

h i g h l i g h t s • Estimation of over 4740 road-killed bats during a 5-year period. • Phyllost... more h i g h l i g h t s • Estimation of over 4740 road-killed bats during a 5-year period. • Phyllostomidae bats were the most affected by roadkill in the study area. • Road casualties were more numerous during rainy season. • Collisions occurred 12 times more in four-lane highways than in two-lane ones.

Chiroptera Neotropical, 2011

Atualmente a perda de habitats nativos por desmatamentos tem sido a principal causa de ameaca a b... more Atualmente a perda de habitats nativos por desmatamentos tem sido a principal causa de ameaca a biodiversidade. Estima-se que mais de 88% das aves, 80% dos mamiferos e 88% dos anfibios globalmente ameacados estejam nessa condicao em funcao da supressao de seus habitats nativos. Embora tenha sido considerada uma ameaca teorica ate pouco tempo, ha um consenso de que as mudancas climaticas que estao sendo projetadas pelo Painel Internacional de Mudancas Climaticas (IPCC) para as proximas decadas podem trazer serias consequencias para a biodiversidade.

Anais da Academia Brasileira de Ciências, 2021

The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all ... more The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes.

Biological Conservation, 2018

Tropical dry forests (TDF) are threatened worldwide, affected by conversion to agriculture, fragm... more Tropical dry forests (TDF) are threatened worldwide, affected by conversion to agriculture, fragmentation, fires, and climate change. Most of the remaining TDF are in South America, including Brazil's Caatinga. Understanding how the biota of TDFs responds to habitat loss and climate change is a scientific challenge, especially to diversified groups, such as bats, whose richness and ecological roles in TDF are usually underestimated. We updated and synthesized occurrence data and generated distribution models for Caatinga bats considering present and future scenarios. At least 96 species, 48 genera, and eight families were recorded, including two endemic species; five additional species may occur in the biome. The highest potential species richness occurs in the east, in the Caatinga/Atlantic Forest ecotone; the lowest in the west, in the Caatinga/Cerrado ecotone. Current and projected deforestation led to a reduction of 65% in areas with very high potential richness, and only 0.4% will remain within current protected areas. In a business as usual scenario (i.e., high and fast habitat loss + low in situ protection + high potential exposure to climate change) the bat fauna of the Caatinga will be negatively impacted. Improving the conservation of roosting and foraging sites, with the expansion and/or creation of protected areas is urgently needed.