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1.
Environ Manage ; 73(2): 395-407, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37796334

ABSTRACT

Promoting the diversity of biological communities in areas of agricultural production is a very current debate since protected areas may not be sufficient to ensure biodiversity conservation. Among the biological communities affected by the production areas are birds, which show rapid responses to changes in the landscape. Here we seek to understand how landscape planning, concerning its composition and configuration, in areas with a matrix of planted Eucalyptus spp. forests influences the functional diversity of bird assemblages in the Atlantic Forest. Our results show that the spatial distribution design of planted forests in terms of age, land cover and clone types have effects on bird diversity with regard to functional divergence, functional evenness and species richness. These results reinforce the importance of good management for the maintenance of bird diversity. We found that bird functional diversity in planted forest matrices increased with the proximity index, proportion of native vegetation and age importance value, and is negatively influenced by edge density and proportion of forest plantation. For bird conservation, it is thus better to associate Eucalyptus spp. with other cover types in the landscape. These results corroborate that, to increase bird functional diversity, it is possible to associate conservation and production in the same landscape. Mosaic landscapes have great potential to contribute to the conservation of bird biodiversity outside protected areas. However, decisions regarding the management of planted forests and planning of improved areas intended for conservation seem to be decisive to ensure the maintenance of bird biodiversity.


Subject(s)
Eucalyptus , Animals , Forests , Biodiversity , Biota , Birds/physiology , Ecosystem
2.
Biota Neotrop. (Online, Ed. ingl.) ; 24(2): e20231569, 2024. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1564051

ABSTRACT

Abstract The Atlantic Forest and Cerrado (Brazilian Savannah) contain a large number of endemic species and high species diversity, particularly for medium and large-bodied mammals. However, there is no large-scale assessment of these animals and their spatial distribution. Our study synthesises the literature on medium and large-bodied mammal surveys in the Cerrado and Atlantic Forest to provide insights into their distributions across large spatial scales and identify knowledge gaps to guide future research. We synthesised papers published in three databases, focusing on mammals weighing more than 1kg. Of the 84 papers we found, the majority (57.14%) were on mammals in the Atlantic Forest, while 42.85% were on mammals found in the Cerrado. We gathered records for 116 species, the most common of which were Cerdocyon thous (Linnaeus, 1766), Procyon cancrivorus (Cuvier, 1798) and Chrysocyon brachyurus (Illiger, 1815) (Cerrado); Dasypus novemcinctus (Linnaeus, 1758), Cerdocyon thous (Linnaeus, 1766) and Nasua nasua (Linnaeus, 1766; Atlantic Forest). Our study allowed us to access, for the first time in the Atlantic Forest and Cerrado, the information available about medium and large-bodied mammals. We also highlight important sampling gaps, especially concerning the northern parts of both biomes that we need to address, as well as the differences in density of sampling points that are caused by a smaller concentration of sampling efforts in the Atlantic Forest than what we found in Cerrado. As a consequence, larger extensions of Cerrado present knowledge gaps concerning mammal surveys that need to be investigated in future research.


Resumo A Mata Atlântica e o Cerrado brasileiro abrigam uma enorme quantidade de espécies endêmicas e alta diversidade de espécies, especialmente de mamíferos de médio e grande porte. No entanto, não há uma avaliação em larga escala desses animais e de sua distribuição espacial. Nosso estudo sintetiza a literatura sobre levantamentos de mamíferos de médio e grande porte no Cerrado e na Mata Atlântica, com o objetivo de fornecer informações sobre suas distribuições em larga escala e identificar lacunas no conhecimento para guiar futuras pesquisas. Sintetizamos artigos publicados em três bases de dados, com foco em mamíferos com peso superior a 1 kg. Dos 84 artigos encontrados, a maioria (57,14%) tratava de mamíferos na Mata Atlântica, enquanto 42,85% abordavam mamíferos encontrados no Cerrado. Coletamos registros para 116 espécies, sendo as mais comuns Cerdocyon thous (Linnaeus, 1766), Procyon cancrivorus (Cuvier, 1798) e Chrysocyon brachyurus (Illiger, 1815) (Cerrado); Dasypus novemcinctus (Linnaeus, 1758), Cerdocyon thous (Linnaeus, 1766) e Nasua nasua (Linnaeus, 1766; Mata Atlântica). Nosso estudo também mostra as lacunas no levantamento especialmente em relação às distribuições ao norte dos biomas, que precisam ser resolvidas, assim como a diferença na densidade de pontos que é causada pela menor concentração de amostragens na Mata Atlântica do que o que encontramos no Cerrado. Como consequência, existem largas extensões do Cerrado que apresentam lacunas no levantamento de mamíferos que precisam ser investigados em pesquisas futuras.

3.
Nature ; 618(7965): 444-445, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37268838
4.
J Environ Manage ; 343: 118256, 2023 Oct 01.
Article in English | MEDLINE | ID: mdl-37247542

ABSTRACT

Although a growing body of literature recognises the importance of rarity for biodiversity conservation, it is unclear how the interaction of different forms of rarity, extrinsic causes of extinction, and protection affect species' vulnerability. Here we addressed the extinction vulnerability of 2203 shrub and tree species of the South American savanna (SAS). For this, species were attributed a form of rarity, a synergistic risk index (SRI), and a protection index (PI). The SRI combines three extrinsic causes of extinction (climate hazard, fire frequency, and human footprint). The PI is the ratio between the number of a species occurrences within protected areas and the total number of occurrences in the SAS. By combining the SRI and PI, we classified common and rare species into five vulnerability classes. Some regions of the SAS show high values of climate hazard, fire frequency, human footprint, and SRI. Each extrinsic cause of extinction is differently distributed across the SAS and shows no or low spatial congruence with the SRI. Many species show a low ratio of occurrences within PAs, which in combination with high SRI results in high vulnerability to extinction. Surprisingly, the number of common species in the higher vulnerability classes is higher than of rare species. Common and rare species in different vulnerability classes occur in somewhat different locations across the SAS and mainly constitute spatially incongruent centres with high species richness. Given our results, we propose that strategies for the effective conservation of SAS species are challenging and must be carefully designed.


Subject(s)
Conservation of Natural Resources , Trees , Humans , Grassland , Biodiversity , South America , Ecosystem , Extinction, Biological
7.
PeerJ ; 11: e14027, 2023.
Article in English | MEDLINE | ID: mdl-36643651

ABSTRACT

The genus Radiodiscus includes minute terrestrial snails occurring throughout the American continent. We assessed the conservation status of eight poorly known Chilean Radiodiscus species using the International Union for Conservation of Nature (IUCN) and NatureServe categories and criteria. Under the IUCN guidelines the species were assessed using the Criterion B of geographic range, which considers the extent of occurrence (EOO) and area of occupancy (AOO) as subcriteria. For NatureServe we used these two parameters plus the number of occurrences, ecological viability, and threats. Considering species rarity and possible sampling bias, we also used ecological niche modeling to determine climate and environmental tolerances and predict potential species distributions analyzing bioclimatic and geographical layers. Radiodiscus australis, R. coarctatus and R. quillajicola were listed as Critically Endangered by IUCN and NatureServe standards; R. coppingeri, R. flammulatus, R. magellanicus and R. villarricensis as Endangered by both methods; while R. riochicoensis as Endangered by IUCN standards and Vulnerable by NatureServe standards. Niche modeling results indicated that Radiodiscus species respond to different environmental conditions and that the predicted distribution areas contain suitable habitats beyond the current ranges, which may be helpful for future management plans. Nature-based sport tourism, forestry activities, urbanization, roads, pollution, mining, forest fires, livestock, volcanism, tsunamis, soil erosion and introduced species are among the major threats affecting these snails. Based on the low number of occurrences and the threats identified, the most at-risk species are R. coarctatus and R. quillajicola (one record), R. australis (two records) and R. villarricensis (three records); the latter two lacking occurrences within protected areas. Compiling our findings, we propose a list of actions to preserve Chilean Radiodiscus species.


Subject(s)
Endangered Species , Gastropoda , Animals , Extinction, Biological , Chile , Ecosystem
12.
Nature ; 601(7892): 178-179, 2022 01.
Article in English | MEDLINE | ID: mdl-35017710
13.
PeerJ ; 9: e11952, 2021.
Article in English | MEDLINE | ID: mdl-34532157

ABSTRACT

The endangered Chiapas killifish Tlaloc hildebrandi is an endemic freshwater species that lives in four subbasins of the Grijalva and Usumacinta basins, and one of the most geographically restricted species of the Produndulidae family. The species was originally described as endemic to springs in the high limestone plateau in San Cristóbal de Las Casas in the Río Amarillo subbasin (upper Grijalva basin). However, it was recently recorded in the Jataté and Tzaconejá subbasins in the upper Usumacinta basin, thereby expanding its known distribution range. The discovery of these populations is relevant not only for the conservation of the species but also for a better understanding of its evolutionary history. Currently, the scarce populations of T. hildebrandi, found in only a few localities in the Grijalva and Usumacinta basins, are fragmented and living under unfavorable conditions. Here, we analyzed three mitochondrial (mt-atp8&6 and mt-nd2) and one nuclear (nuc-s7) marker in order to assess the genetic diversity and population structure of T. hildebrandi. We found that, in comparison with other endangered freshwater fish species from Mexico, T. hildebrandi showed a lower level of genetic diversity (mt-nd2: h = 0.469, π = 0.0009; mt-atp8&6: h = 0.398, π = 0.001; and nuc-S7: h = 0.433, π = 0.001). Moreover, the analyzed populations exhibited a strong genetic structure in accordance with their geographic distribution, and can be placed into three genetic clusters: (1) Amarillo plus Chenhaló in the upper Grijalva basin, (2) Jataté, and (3) Tzaconejá, both in the upper Usumacinta basin. On the basis of our results, we propose the recognition of at least three evolutionarily significant units (ESUs) for the species and the urgent implementation of ex situ and in situ conservation and management efforts that consider the genetic background of the species.

15.
J Environ Manage ; 292: 112732, 2021 Aug 15.
Article in English | MEDLINE | ID: mdl-33992867

ABSTRACT

Several strategies have been adopted to optimize biodiversity conservation. The use of fauna and flora species as flagships can help increase public commitment and raise funds for their conservation. However, species choices must be well balanced, considering not only intrinsic aspects (e.g., risk of extinction and ecological role), but also social, cultural, and economic aspects of the region where the flagship will be adopted. Brazil is one of the countries with the greatest diversity on the planet. Nevertheless, there are several challenges associated with natural resources conservation. Flagships have been adopted informally for decades throughout the country but there are no efforts to evaluate these strategies results for the preservation of the selected species. The aim of this study was to carry out an extensive survey on regional flagship species, their conservation status, level of endemism, and domestic legislation currently in force for their protection or human use. A total of 62 flagships were identified, with at least one species of flora and one of fauna for each of the 27 Brazilian Federative Units. The animals most commonly used as regional symbols are birds, followed by mammals. Flora species used as regional symbols are quite diverse. However, they are all somehow used by humans. As for legal protection, there are government measures for endangered species. Nevertheless, most species used as regional symbols are not at risk of extinction and, for this reason, do not receive any legal protection. Moreover, while some flagships are endemic, others are alien species, indicating that this criterion is not considered when choosing regional symbols. In the overall analysis it was noted that species choice could be optimized to highlight the national biodiversity. Despite efforts to establish legal measures for their preservation, few effective results have been observed. Therefore, improved effective measures for their conservation should be adopted to guarantee the effectiveness of flagship species for biodiversity conservation.


Subject(s)
Biodiversity , Conservation of Natural Resources , Animals , Brazil , Endangered Species , Government , Humans
16.
Zootaxa ; 4959(1): zootaxa.4959.1.1, 2021 Apr 15.
Article in English | MEDLINE | ID: mdl-33903576

ABSTRACT

Syrphidae, more commonly known as flower flies, are considered one of the most important Diptera families worldwide because of their critical role in pollination, biological control and decomposition of organic matter. The study of these flies in Chile has stagnated due to a lack of local experts as well as the absence of an updated catalog of species. This study is an attempt to remedy the latter of these issues by providing an illustrated and updated catalog to the Syrphidae of Chile. Species are presented under currently accepted names, with synonyms and previous combinations listed and original references. Type localities, world and Chilean distribution by geopolitical Chilean regions, taxonomic and biological notes, a complete record of bibliographic references and extinction risk under IUCN Red List criteria are provided. This catalog recognizes 132 species of Syrphidae, belonging to four subfamilies (Eristalinae, Microdontinae, Pipizinae and Syrphinae), 13 tribes and 47 genera. A total of 46 species (34.84 %) is restricted to the geopolitical territory of Chile. Eight species are considered exotic, one is considered incertae sedis and three are based on doubtful records. Seventeen species of 10 different genera (Copestylum Macquart, 1846; Dolichogyna Macquart, 1842; Eosalpingogaster Hull, 1949b; Eupeodes Osten Sacken, 1877; Meromacrus Rondani, 1848; Palpada Macquart, 1834; Paragus Latreille, 1804; Sphiximorpha Rondani, 1850; Sterphus Philippi, 1865 and Toxomerus Macquart, 1855) are reported from Chile for the first time. A total of 44 species (33.33 %) reported from Chile are directly threatened by human activities such as agriculture, forestry, mining and/or urbanization and indirectly by climate change. The gaps found in the geographic distribution of Chilean flower fly species and what it means for its use by disciplines such as ecology, floral biology and agronomy, are discussed. In addition, the use of this illustrated catalog for biological conservation, the potential definition of priority areas and ecosystem management plans based on this group of Diptera are also discussed.


Subject(s)
Diptera , Animal Distribution , Animals , Chile , Diptera/anatomy & histology , Diptera/classification , Ecosystem , Flowers , Pollination , Species Specificity
18.
Mol Ecol ; 29(14): 2567-2582, 2020 07.
Article in English | MEDLINE | ID: mdl-32542770

ABSTRACT

Monarch butterflies are known for their spectacular annual migration in eastern North America, with millions of monarchs flying up to 4,500 km to overwintering sites in central Mexico. Monarchs also live west of the Rocky Mountains, where they travel shorter distances to overwinter along the Pacific Coast. It is often assumed that eastern and western monarchs form distinct evolutionary units, but genomic studies to support this notion are lacking. We used a tethered flight mill to show that migratory eastern monarchs have greater flight performance than western monarchs, consistent with their greater migratory distances. However, analysing more than 20 million SNPs in 43 monarch genomes, we found no evidence for genomic differentiation between eastern and western monarchs. Genomic analysis also showed identical and low levels of genetic diversity, and demographic analyses indicated similar effective population sizes and ongoing gene flow between eastern and western monarchs. Gene expression analysis of a subset of candidate genes during active flight revealed differential gene expression related to nonmuscular motor activity. Our results demonstrate that eastern and western monarchs maintain migratory differences despite ongoing gene flow, and suggest that migratory differences between eastern and western monarchs are not driven by select major-effects alleles. Instead, variation in migratory distance and destination may be driven by environmentally induced differential gene expression or by many alleles of small effect.


Subject(s)
Animal Migration , Butterflies , Gene Flow , Genetics, Population , Alleles , Animals , Butterflies/genetics , Flight, Animal , Genome, Insect , Genomics , Mexico , Phenotype , Polymorphism, Single Nucleotide
19.
Biol Rev Camb Philos Soc ; 95(5): 1467-1478, 2020 10.
Article in English | MEDLINE | ID: mdl-32515886

ABSTRACT

Herein, I review existing criticisms of the field of invasion biology. Firstly, I identifiy problems of conceptual weaknesses, including disagreements regarding: (i) definitions of invasive, impact, and pristine conditions, and (ii) ecological assumptions such as species equilibrium, niche saturation, and climax communities. Secondly, I discuss methodological problems include the misuse of correlations, biases in impact reviews and risk assessment, and difficulties in predicting the effects of species introductions or eradications. Finally, I analyse the social conflict regarding invasive species management and differences in moral and philosophical foundations. I discuss the recent emergence of alternatives to traditional invasion biology approaches, including the concept of novel ecosystems, conciliation biology, and compassionate conservation. Understanding different value systems will be the first step to reconciling the different perspectives related to this controversial topic.


Subject(s)
Ecosystem , Introduced Species , Biology
20.
Zookeys ; 926: 95-131, 2020.
Article in English | MEDLINE | ID: mdl-32336922

ABSTRACT

The Lesser Antilles, in the Eastern Caribbean, is inhabited by three Iguana species: the Lesser Antillean iguanaIguana delicatissima, which is endemic to the northernmost islands of the Lesser Antilles, the introduced common iguana from South America, Iguana iguana iguana, represented also by the two newly described endemic subspecies Iguana iguana sanctaluciae from Saint Lucia and Iguana iguana insularis from Saint Vincent and the Grenadines, and Grenada, and the introduced Iguana rhinolopha from Central America. Drawing on both morphological and genetic data, this paper describes the Iguana populations from Saba and Montserrat as a new species, Iguana melanoderma. This species is recognized on the basis of the following combination of characteristics: private microsatellite alleles, unique mitochondrial ND4 haplotypes, a distinctive black spot between the eye and tympanum, a dorsal carpet pattern on juveniles and young adults, a darkening of body coloration with aging (except for the anterior part of the snout), a black dewlap, pink on the jowl, the high number of large tubercular nape scales, fewer than ten medium sized-triangular dewlap spikes, high dorsal spikes, and lack of horns on the snout. This new melanistic taxon is threatened by unsustainable harvesting (including for the pet trade) and both competition and hybridization from escaped or released invasive alien iguanas (I. iguana iguana and I. rhinolopha) from South and Central America, respectively. The authors call for action to conserve Iguana melanoderma in Saba and Montserrat and for further research to investigate its relationship to other melanistic iguanas from the Virgin Islands and coastal islands of Venezuela.

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