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Several studies have associated the chytrid fungus Batrachochytrium dendrobatidis with anuran population declines worldwide. To date, the fungus has been found in Africa, the Americas, Australia, and Europe. However, it has never been reported to occur in the Atlantic forest or Brazil. Based on morphological, histological, and molecular data, we encountered evidence of B. dendrobatidis infection in a high-altitude stream-dwelling Brazilian anuran species, Hylodes magalhaesi (Leptodactylidae). One population (Municipality of Camanducaia, State of Minas Gerais) was surveyed from 2001 to 2005. Tadpoles lacking teeth were observed and collected in 2004. Histological and molecular analyses identified infection by B. dendrobatidis. Although infected tadpoles seem nowadays to co-exist with the disease, our results are alarming due to the highly endangered situation of the Brazilian Atlantic forest and its fauna. Effects of the chytrid infection on the studied population are still unknown. Further investigations are needed to provide information on its distribution in relation to other populations of H. magalhaesi.
The use of phylogenies in ecology is increasingly common and has broadened our understanding of biological diversity. Ecological sub-disciplines, particularly conservation, community ecology and macroecology, all recognize the value of evolutionary relationships but the resulting development of phylogenetic approaches has led to a proliferation of phylogenetic diversity metrics. The use of many metrics across the sub-disciplines hampers potential meta-analyses, syntheses, and generalizations of existing results. Further, there is no guide for selecting the appropriate metric for a given question, and different metrics are frequently used to address similar questions. To improve the choice, application, and interpretation of phylo-diversity metrics, we organize existing metrics by expanding on a unifying framework for phylogenetic information.
Generally, questions about phylogenetic relationships within or between assemblages tend to ask three types of question: how much; how different; or how regular? We show that these questions reflect three dimensions of a phylogenetic tree: richness, divergence, and regularity. We classify 70 existing phylo-diversity metrics based on their mathematical form within these three dimensions and identify ‘anchor’ representatives: for α-diversity metrics these are PD (Faith's phylogenetic diversity), MPD (mean pairwise distance), and VPD (variation of pairwise distances). By analysing mathematical formulae and using simulations, we use this framework to identify metrics that mix dimensions, and we provide a guide to choosing and using the most appropriate metrics. We show that metric choice requires connecting the research question with the correct dimension of the framework and that there are logical approaches to selecting and interpreting metrics. The guide outlined herein will help researchers navigate the current jungle of indices.
Reintroductions of plant species are increasingly popular in conservation practice. Steppe grasslands contain many rare and endangered plant species that are potential objects for such reintroductions. Most reintroduction projects, however, can only target a restricted number of species, which raises the question of how species should be prioritised. Here, we present a method to select priority species for reintroduction based on species' characteristics that are widely used in conservation practice. We first determined the local species pool containing those vascular plant species that occurred both in our target region (Thuringia, Germany) and target habitat (steppe grasslands), yielding 369 species. With the help of an a priori filter that selected currently endangered species with limited distribution, 136 potential target species were determined. These potential target species had experienced stronger decline, had a narrower phytosociological amplitude and were more likely to be species of the Festuco-Brometea class and the Festucetalia valesiacae order than non-target species. Potential target species were then ranked by a points system based on ten conservation-relevant characteristics of the species from the categories "threat and protection status", "distribution and decline", and "habitat affiliation". In the ranking, six steppe grassland plant species (Astragalus exscapus, Bothriochloa ischaemum, Prunella laciniata, Pulsatilla pratensis subsp. nigricans, Scorzonera purpurea, and Seseli hippomarathrum) achieved the highest scores. An additional seven species not specifically characteristic for steppe grasslands also scored highly. A post hoc evaluation of these 13 highest scoring species based on additional conservation criteria left five species (Astragalus exscapus, Linum leonii, Orchis morio, Pulsatilla pratensis subsp. nigricans and Scorzonera purpurea) as species with highest priority for reintroductions and another five species as highly suitable for reintroductions. Associations between the ranking order and different ranking criteria revealed that a species’ threat and rarity in Thuringia and its protection status had the highest representation in the ranking, followed by threat in Germany, regional decline and habitat affiliation. In contrast, international threat and responsibility of Thuringia for its conservation had only low representation in the ranking, probably because these characteristics applied to only a few species. The ranking list gives a selection of species for reintroductions, which combined with additional information based on comprehensive local and floristic knowledge, allows the identification of the species with the highest priority. Our method can be transferred to other regions or habitat types.
The Stachytarpheta longispicata complex is a group of seven accepted infraspecific taxa endemic to the Brazilian Cerrado, defined by its pedicellate flowers with salmon or dark red corollas. Due to the great morphological variation and very brief original descriptions, these taxa have controversial circumscriptions. We evaluated the morphological variation through the morphometric analysis of 11 natural populations in addition to nomenclatural types to assess the current infraspecific circumscriptions and clarify the limits of these taxa. A set of 36 continuous vegetative and reproductive characters was measured for each of the 115 specimens sampled, encompassing the morphological variability in the group and its geographic distribution. A compiled data matrix formed the basis for the multivariate analysis (UPGMA, PCA, and DA). Our results recovered five consistent groups corresponding to the four subspecies, and all three recognised varieties treated in the same morphological group. Quantitative and qualitative characters not previously studied in detail are important to delimit the five groups. A taxonomic rearrangement is proposed for the complex, circumscribing five distinct species: Stachytarpheta brevibracteata, S. longipedicellata, S. longispicata, S. minasensis, and S. ratteri. The taxonomic treatment includes four new combinations and names at new rank, two new synonyms, and one lectotype. Descriptions, an identification key, geographical distribution map, illustrations, and provisional conservation assessments are also provided.
A new species of Microphotina Beier, 1935 (Mantodea: Photinaidae: Microphotinini), Microphotina cristalino sp. nov., is described from Mato Grosso, Brazil based on two male specimens. The new species extended the distribution of Microphotina to the southern limits of the Amazon rainforest, in the Cerrado-Amazônia ecotone. A synthesis of the taxonomy, systematics, natural history, and geographic distribution of Microphotina spp. is provided, along with an updated dichotomous key to species. The hypothesis that Microphotina represents a canopy-dwelling lineage is formulated. The role of praying mantises as flagship species for insect and Amazon conservation is briefly discussed.
Juga is a genus of freshwater snails distributed from northern Washington to central California. The taxonomy and classification of the genus has a long and complex history, driven mainly by the features of their highly variable shells. The number of recognized species has fluctuated from ~9 to 11; however, it has been claimed that the actual diversity may be three times that number. We here present a systematic revision using a recently published molecular phylogeny as a framework, which supported the interpretation that there are only nine valid species. Comprehensive review of type material and original descriptions for all available species-group names indicates that almost all species previously considered valid were para- or polyphyletic grades of organization in shell morphology. Most species previously suggested to be putatively new were confirmed to be morphological variants of species already described. Species accounts include complete synonymies and partial chresonymies; the shells and radulae are illustrated and described. Lectotypes are designated for Melania plicifera Lea, 1838, M. silicula Gould, 1847, and M. rudens Reeve, 1860. Three species, Juga caerulea sp. nov., J. canella sp. nov., and J. douglasi sp. nov., are described as new and one species is excluded from the genus. The subgenera Calibasis D.W. Taylor, 1966 and Idabasis D.W. Taylor, 1966 are synonymized with Juga.
Our recent surveys of the herpetological diversity of the West African Togo Hills documented a total of 65 reptile and amphibian species, making Kyabobo National Park one of the most diverse sites surveyed in Ghana. We provide accounts for all species recorded along with photographs to aid in identification. We recorded 26 amphibians, including six new records for Kyabobo N. P., one of which is a record for the Togo Hills. Our collection of reptile species (22 lizards, 16 snakes, and one crocodile) also provides new records and range extensions for Kyabobo N. P., such as the first observation of the dwarf crocodile, Osteolaemus tetraspis. Amphibian species still lacking from our surveys in the Togo Hills include several species that are adapted to fast running water or large closed forests, like the Togo toad, Bufo togoensis and the slippery frog, Conraua derooi. Appropriate habitat for such species still remains in Kyabobo, highlighting the need for additional survey work. We draw attention to the importance of conserving forest stream habitats, which will in turn help ensure the persistence of forest-restricted species. We also highlight those species that may prove most useful for evolutionary studies of West African rain forest biogeography.
We report on the activities of the European Dry Grassland Group (EDGG) during the last year, namely the 8th European Dry Grassland Meeting in Uman', Ukraine in June 2011, the 3rd EDGG Research Expedition in Bulgaria in August 2011, the 4th EDGG Research Expedition in Sicily in April 2012, as well as the completed and forthcoming EDGG-coordinated special features in international journals. Then we provide a brief bibliometrical analysis of the Dry Grassland Special Features in Tuexenia since 2005. The 32 contributions of the years 2005–2011 constituted approx. 17% of the overall content of Tuexenia in this period. Including this 7th Dry Grassland Special Feature, sixty-one authors from 12 countries have contributed to these Special Features, guest-edited by yearly changing teams from a total of 16 guest editors. In the years with statistically reliable data, contributions in the Dry Grassland Special Features have been cited approximately four times as much as regular Tuexenia contributions. It is likely that this fact together with the internationality of the Special Features has contributed to the final inclusion of the journal in the Web of Science in 2011. Finally, we introduce the four research articles of this 7th Dry Grassland Special Feature. Two of them are focusing on vegetation change and restoration issues of cryptogam-rich sand dunes in the Netherlands and calcareous grasslands in Bavaria (Germany), respectively. The others, dealing with siliceous grasslands in Hesse (central Germany) and the results of EDGG Research Expedition 2009 to Transylvania (Romania), focus on syntaxonomy.
Bumblebees (Bombus Latreille, 1802), because of their large body size, bright colours and activity at times and places that coincide with biologists, are an example of a group of insects that is particularly well represented in museum collections. This is important if taxonomic revisions are to achieve greater comparability among species. Bumblebees have also attracted particular attention because they are especially ecologically and economically valuable for pollination in north temperate regions, where they are now becoming increasingly threatened. I argue that the what, the where, and the how of effective conservation management may be informed by understanding the divergent characteristics that have affected their biogeographical past: by helping us to see ‘the woods’, not just ‘the trees’, of their habitat needs. Identifying suitable habitat should be part of reconstructing historical biogeography within taxonomic revisions. For bumblebees, for example, biogeographical analysis associates major taxonomic groups either with flower-rich lowland grasslands or with flower-rich montane grasslands, highlighting their contrasting requirements for: nest sites, flowers of different depths, pollen-plant families, and especially the differing importance of early spring and late summer flowers for breeding success. This broad view of species groups helps filter the less important idiosyncrasies from local case studies in order to focus conservation actions.
The continuous conversion of natural wildlife habitats into agricultural areas, as well as the fragmentation of the last wildlife refuges, is increasing the interface between people and wildlife. When wildlife negatively impacts on people and vice versa, we speak about human-wildlife conflicts (HWCs). This definition includes losses on both sides and takes into consideration the rooting of most of these conflicts between different groups of interest, such as advocates for nature conservation and economic groups. The centres of highest biodiversity are located in developing countries, which are also characterized by poverty. In African and Asian countries, people living in the vicinity of national parks and other conservation areas mostly receive only little support through the government or conservation organisations. Especially for those people who are dependent on agriculture, damage to fields and harvests can have catastrophic consequences. If the species causing damage is protected by national or even international law, the farmer is not allowed to use lethal methods, but has to approach the authority in charge. If this agency, however, cannot offer appropriate support, resentment, anger or even hate develops, and the support for wildlife conservation activities declines. For this reason, HWCs were declared as one of the most important conservation topics today, being particularly relevant for large and threatened species such as the African and Asian elephant, hippopotamus and the greater one-horned rhino, as well as for large predators. Up to today, no general assessment scheme has been recommended for damage caused by protected wildlife species.
In my study, HWCs in Asia and Africa are compared, focussing on all herbivorous species identified which damaged crops. For the French NGO Awely, des animaux et des hommes, I developed a detailed assessment scheme suitable for all terrestrial ecosystems, and any type of HWCs and any species (Chapter 2). This HWC assessment scheme was used in four different study areas located in two African countries (South Luangwa/Zambia (SL), Tarangire/Tanzania (TA)) and two Asian countries (Bardia/Nepal (BA) and Manas/India (MA)). This scheme ran for six consecutive years (2009 to 2014) for Zambia, Nepal and India and two years (2010 to 2011) for Tanzania. To carry out the assessments, I trained local HWC officers (Awely Red Caps) to assess HWCs by field observations (measurement of damage, identification of species through signs of presence, landscape attributes etc.) and interviews with aggrieved parties (socio economic data). Results of this assessment are presented in Chapters 2-4.
To determine whether elephants prefer or avoid specific crop species, two field experiments were carried out, one in SL and one in BA (Chapter 5 and 6). For this, two test plots were set up and damage by elephants (and other herbivores) were quantified.
Within this doctoral thesis, 3306 damage events of 7408 aggrieved parties were analysed. In three out of the four study areas (SL, BA, MA), elephants caused the highest number of damage events compared to all other wildlife species, however, in TA, most fields were damaged by zebra. Furthermore, the greater one-horned rhino, hippopotamus, wild boar, bushpig, deer and antelope, as well as primates, caused damage to fields and harvests. Damage to houses and other property were nearly exclusively caused by elephants.
With this doctoral thesis I was able to show that season, crop availability, type and the phenological stage of the crop played an important role for crop damaging behavior of herbivores (Chapter 2). Elephants especially damaged rice, maize and wheat and preferred all crop types in a mature stage of growth. In contrast, rhinos preferred wheat to rice and similar to antelope and deer, they preferred crops at earlier stages of growth, before ripening. Crop damage by wildlife species varied strongly in size; most damages fell below 40% of the total harvest per farmer, but in several cases (3 to 8% depending on the study area), harvests were completely destroyed. Interestingly, during times of low nutritional availability in the natural habitat (dry season), crop damages in all four study areas were significantly less than during other seasons.
In all four study areas, crop protection strategies, such as active guarding in the fields, chasing wildlife with noise or fire torches or erecting barriers, were used. In some cases protection strategies were combined. Analysis of data revealed that traditional protection strategies did not reduce the costs of damage (Chapter 3). In some cases, costs of damage, on protected fields were even higher than for unprotected fields. Only in MA did strategic and cohesive guarding significantly reduce crop damage by wildlife species.
Besides damage in the fields, elephants also caused damage to properties in the villages. In search for stored staple crops, they damaged houses, grain stores and kitchens. Such damage was analysed in three study areas (SL, BA, MA) (Chapter 4). Although property damage occurred less frequently compared to crop damage in the fields, the mean cost of this damage was found to be double in BA/MA and four times higher in SL, compared to the costs of crop damage in the fields. It is further remarkable that property damage significantly increased towards the dry season, when the harvest was brought into the villages.
The findings of this study underpin the assumption that wildlife herbivores, especially elephants, are lured to fields and crops because the highly nutritional food (crop) being readily available. Traditional crop protection is cost and labour intensive and does not reduce the costs of damage. For this reason, crop types, which are thought to be not consumed by elephants were systematically tested on their attractiveness in field experiments in SL and BA (Chapter 5 and 6). In SL, lemon grass, ginger and garlic were proven to be less attractive to African elephants than maize and in BA, basil, turmeric, chamomile, coriander, mint, citronella and lemon grass were found to be less attractive to Asian elephants than rice.
The results of this doctoral thesis are relevant for the management of wildlife conservation as they can lead to new approaches to the mitigation of HWCs in African and Asian countries. Finally, specific needs for more scientific research in this field have been identified.