Senckenberg Natural History Collections Dresden

Herpetology

Research

tree stump fsc

 

 

 

anthropogenic Impacts on biodiversity 

 
Selected projects
 
Amphibians on the Cutting Edge

 

Iwokrama Forest

According to the Millennium Ecosystem Assessment (MEA), habitat change has a major and growing impact on tropical forest ecosystems. Unsustainable wood extraction ranks among the number one direct causes of deforestation and forest degradation. In fact, timber harvesting is currently the most common commercial utilisation activity in tropical forests and it has been identified as one of the major threats to global vertebrate diversity. As a result of its paramount role in altering tropical forest ecosystems it has recently been brought at a centre stage in discussions on biodiversity mainstreaming and the development of new concepts aimed at bringing increasing deforestation to a halt.

Tropical amphibians are a diverse vertebrate group that is threatened by multiple factors. Since their first appearance approximately 299-251 million years ago, this group has evolved into what could be the most diverse group of tetrapod vertebrates. Currently, more than 7,000 amphibian species are recognized. Since the mid 1980s the total number of recognized species has increased by over 60% and given these rates of new descriptions, amphibians could possibly outnumber bird and reptile species within the next years. Despite this alleged evolutionary success story, many amphibian species throughout the world are facing severe population declines or even extinction. Due to their physiology, mostly short generation times, and predominantly biphasic lifecycle, amphibians are particularly sensitive with respect to habitat changes and altered microclimatic conditions that accompany these changes.

marked treeWithin the scope of several projects in Brazil, Guyana, Suriname, and West Africa, we address the question of whether and how anthropogenic habitat alteration, such as logging, affects diversity patterns in complex tropical amphibian communities. We particularly focus on functional aspects of diversity and interactions between different diversity levels (species, functional, trophic diversity) at different scales (local, regional, cross-regional). Our general goal is to elucidate the interactions between biodiversity and ecosystem functioning in complex tropical systems under the influence of human induced changes.
 

In combination with supplementary amphibian community data sets from other globally important regions,  e.g. Southeast Asia, these data sets are used in large-scale meta-analyses with the ultimate aim of establishing models of ecosystem change and decay that incorporate empirical patterns of diversity change and potential ecological cascading.   

Projects supported by DFG (ER 589/2-1), DAAD, and Tropenbos International Suriname

Find out more about these projects: 

Overview of activities in the Guiana ShieldASG/IUCN FrogLog 100th anniversary issue, Global Focus, 52-53. ]

SEED Research Library: The Green Heart of Guyana Project

Iwokrama News Wire 2011: Amphibian Diversity in selectively logged forests of Iwokrama 

Sustainable Management of Tropical Rainforests -The CELOS Management System: Recovery of an anuran community from logging disturbance

Senckenberg Expedition Log: Guiana Shield Expedition

 

Tropical agroecosystems under land-use and climate change

 

Caatinga Itaparica

Human alteration of the global environment, including anthropogenic climate change and habitat alteration through land-use, has triggered the sixth major extinction event in the history of life. These changes in biodiversity alter ecosystem processes and change the resilience of ecosystems to environmental change. This has profound consequences for services that humans derive from ecosystems. Recent studies suggest that declining biodiversity and habitat alteration synergistically influence the predictability of ecosystem functioning. Amphibians play a pivotal role in the functioning of ecosystems and they support many ecosystem services (ESS), particularly in regions recently undergoing dramatic land use changes. At the same time this diverse vertebrate group is particularly susceptible to environmental degradation and experiences dramatic global population declines. Within the scope of the bi-national interdisciplinary project INNOVATE funded by the Federal Ministry of Education and Research, we investigate the impact of land-use and climate change on the amphibian (and reptile) diversity of the Itaparica reservoir, a largely impacted Caatinga (xerix shrubland and dry forest) area located in the northeastern part of Brazil.


We specifically take into account the effects of land-use change on coupled predator-prey interactions in agro-ecosystems and the impacts of agrochemicals on amphibian populations. A paramount ESS in these human-impacted ecosystems is biological pest control by vertebrate predators, in case of the Caatinga biome, particularly mostly opportunistic amphibian and reptile predators. We will therefore analyze the links between amphibian and reptile diversity and arthropod-pest species abundance along an existing land use gradient.

innovate logo

INNOVATE consists of twenty-two, bi-nationally staffed research modules that belong to seven sub-projects (SP). German partners are the Technical University Berlin (TUB), University of Hohenheim (UHOH), University of Applied Sciences Dresden (HTW), Senckenberg Natural History Collections Dresden (SNSD), Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB), and the Potsdam Institute for Climate Impact Research (PIK). The Brazilian partners comprise two federal universities at Recife (UFPE and UFRPE), the Agricultural Institute of Pernambuco state (IPA), the Technology Institute of Pernambuco (ITEP), the soil section of the Brazilian Agricultural Research Corporation (EMBRAPA Solos), and the National Institute of the Semi-Arid Region (INSA). 

Projects supported by BMBF/DLR (BMBF 01LL0904A), SP4 in collaboration with TU Berlin & HTW Dresden

Find out more about Innovate:   

Official project web siteInterplay among multiple uses of water reservoirs via innovative coupling of substance cycles in aquatic and terrestrial ecosystems

BMBF / FONA site: Modul A Sustainable Land Management - Interactions between climate change, land management and ecosystem services 

PhD-Blog : Innovate PhD platform and information pool

Facebook site: Innovate on face book

 

Biological Invasions and exotic species


selected projects
 
Non-invasive invaders from the Caribbean
 

Eleu. johnstonei The neotropical frog Eleutherodactylus johnstonei (Johnstone’s Whistling frog) has been referred to as a highly invasive species on grounds of its wide distribution and is expected to extend its range significantly based on recent climate model assumptions. The frog was introduced to a number of South American mainland localities, including Guyana, French Guiana, Venezuela, and Colombia. Other species of the genus have become invasive on oceanic islands such as Hawaii where they pose serious biological and economical problems. In this project we assess the actual status and invasion potential of the introduced E. johnstonei using statistical habitat models in combination with field monitoring routines of introduced populations in French Guiana and Guyana.  Field based studies are complemented by detailed quasi-experimental studies on introduced greenhouse populations in several European botanical gardens, in which frogs were introduced both deliberately and unintentionally via plants from original field localities. 

Project in collaboration with David Massemin (St. Laurent du Maroni, Fr. Guiana) and Ingo Kowarik (Ecosystem Science, Technische Universität Berlin, Germany), Heinz Schneider (Botanical Garden and Institute, Universität Basel, Switzerland)

IUCN/SSC (ISSG) Report featuring this study

 

population Ecology and Conservation


selected projects

Bridging the gap
 

Hyla arborea

The European tree frog (Hyla arborea), once widespread in the German lowlands, has experienced tremendous population declines in the last few decades. It has therefore become one of the flag ship species for conservation in Central Europe and is now listed as endangered within most of its Central European range. Many declines were caused by massive habitat destruction and intensive land use during recent years. The continuous modification of landscapes by human activities leads to the damage and loss of natural habitats as well as to their fragmentation. The European tree frog is particularly prone to fragmentation of suitable habitats, i.e. warm low-watered non-eutrophicated ponds without fish. Although conservation areas have been safeguarded in many countries, they often are spatially isolated remnants in otherwise intensively used landscapes. Isolation and fragmentation prevent the species from migrating and may furthermore lead to increased genetic subdivision of populations, higher inbreeding and the loss of genetic diversity within populations.
In this project we assess the population structure and population dynamics of tree frog populations in the Biosphere Reserve “Flußlandschaft Elbe”, Brandenburg, northern Germany. Populations in the area are known to be fragmented but it is not understood whether this is due to historical distribution and dispersal patterns or recent fragmentation of habitats. In a synthetic approach that combines population ecological (habitat models and meta-population analysis) and population genetic (micro satellites) methods, we aim at resolving current distribution patterns and elucidating the population structure in order to provide crucial data needed for potential reintroduction efforts.

Final Report (in German only)

Conservation flagships or doomed to become extinct?

 

Atelopus sp

Governments of the Guiana Shield (GS) countries in northern South America are at a crossroads concerning decisions and tradeoffs among utilisation, conservation and preservation of their forests and thus substantial parts of the region’s biodiversity.The Guyana based organisation Iwokrama International Centre for Rainforest Conservation and Development(www.iwokrama.org/), an international not-for-profit organisation that was established by the Government of Guyana and the Commonwealth Secretariat aims at fostering this decision making process by providing crucial impulses to the debate. The organisation manages nearly one million acres (371,000 ha) of pristine GS rainforest with the aims of testing the concept of a truly sustainable forest, where conservation, environmental balance and economic use can be mutually reinforcing. This concept includes sustainable forestry (e.g. NonTimberForestProducts, selective logging) as well as ecotourism. The latter is often hailed as one of the few indisputable examples of sustainable development at work because it is not only compatible with biodiversity conservation but it also generates economic revenue from land set aside for nature protection. Moreover, ecotourism can help to educate the general public on conservation issues and thereby supports a better management of protected areas.  Turu Falls 

In a joint project we investigate the possibilities and limits of concepts aimed at reconciling ecotourism and (amphibian) conservation in a prospective ecotourism site, the so called Turu Falls, located within the Iwokrama Forest Ecosystem. We particularly assess the population status of two species of the frog genera Atelopus and Allobates and evaluate their potential as conservation flagship species. The project seeks to combine population ecological and conservation genetic analyses of the target species with public awareness aspects within the scope of a scientifically founded feasibility study. 

 

Projects supported by Stiftung Artenschutz (Species Conservation Foundation) Amphibien-Fonds & VDZ Amphibian Conservation Projects,  in collaboration with Dr. Heiko Stuckas, Population Genetics, Senckenberg Dresden & Philippe Kok, Royal Belgian Institute of Natural Sciences & Amphibian Evolution Lab Free University of Brussels

 

Biodiversity Exploration


selected projects
 
Hidden jewels in a forgotten biodiversity hotspot
 

leptoThe last remaining rainforest patches of northern Angola have been largely neglected in biodiversity surveys. However, due to an assumed link with the large Congolese Forest Bioregion and their unique position within the range of Angolan ecosystems they promise to harbour an exceptionally rich herpetofauna. At the same time they are facing immense pressures from increasing deforestation and fragmentation. We are currently conducting rapid biodiversity assessments to generate basic faunistic data through field observations, bioacoustic surveys and DNA barcoding that will ultimately contribute to a better understanding of northern Angolan forest biodiversity. These activities are currently embedded in a “Qualitätsnetz Biodiversität” program of the German Academic Exchange Service (DAAD) under the auspices of the TU Dresden and Universidade Kimpa Vita, Uíge and partially funded by the TU Dresden and Paul Ungerer Stiftung. . 

Project supported byPaul Ungerer Stiftung,  TU Dresden & Universidade Kimpa Vita

Amazing discoveries

 

Community phylogenetics and trait-based ecology

selected projects 
Time to merge - the phylogenetics behind community assembly

data sets

The study of biological diversity has mainly advanced along two lines of research associated with two (only recently) largely separate scientific disciplines (evolutionary biology and ecology). Whereas evolutionary biologists traditionally focus on understanding genetic diversity within populations, while frequently ignoring ecological processes of species assembly in communities, ecologists often focus on understanding community dynamics and usually ignore evolution. This historic and somewhat artificial separation of disciplines has significantly impeded the development of a more comprehensive and profound understanding of biodiversity and its importance for ecosystem functioning and the multiple services that ecosystems provide.

However, the connection between evolutionary history and community ecology has long been recognized as is apparent in Darwin’s (1859) quote:

As species of the same genus have usually, though by no means invariably, some similarity in habits and constitution, and always in structure, the struggle will generally be more severe between species of the same genus, when they come into competition with each other, than between species of distinct genera

At the heart of any evolutionary interpretation of community organisation and thus biodiversity are three general principles that are highlighted in this statement: species are organized and interact in communities, interactions are driven by (extended) phenotypic (trait) differences and/or similarities between species, and (phenotypic) variation has a historical, evolutionary basis. A comprehensive theory of biological communities must therefore contain these three elements: phylogeny, community composition and trait information. Traits sensu lato are indeed key to advances in many fields of the natural sciences and trait-based analyses may in fact represent the only viable approach for community ecology to produce general principles and make sound predictions of community assembly and ecosystem functioning. In aiming for a unified theory of biodiversity, an integration of research between the two disciplines seems inevitable. Recent advances in analytical and computational procedures and an exponential increase in available phylogenetic data provide ideal conditions for both disciplines to merge again.
framework

 

Within the framework of interdisciplinary projects that focus on phylogenetic community ecology of tropical amphibians in changing environments, we analyse patterns of phylogentic structure in communities and potential phylogentic signal in species traits in order to come up with mechanistic predictions of community assembly in space and time. In these projects we combine the outlined elements by integrating phylogenetic analyses (multi-gene community phylogenies) and trait-based community ecological models (phylogenetic comparative and direct trait-based statistical procedures) in a unified approach. 

 

 

 

Projects in collaboration with Frank Dziock (Tierökologie / Angewandter Umweltschutz , Hochschule für Technik und Wirtschaft Dresden, Germany), Miguel Vences (Evolutionary Biology, Technische Universität Braunschweig, Germany), Alexander Keller (DNA Analytics Core Facility, Universität Würzburg)

 

Phylogenetics and Biogeography  

 
selected projects
 
Cryptic Diversity in Changing Times

 

HyalinobatrachiumThe Guiana Shield accounts for more than 25 percent of the world’s remaining tropical rain forests, and it is an important area of diversity and endemism within the Neotropics. The region has long been recognized as one of the major Pleistocene refugia for the Pan-Amazon region. More precisely, it has probably hosted multiple refugia during the late Pliocene and Pleistocene, rather then a single refugium, as previously assumed. Species distributions and distributional boundaries, as well as their evolutionary histories remain largely unknown. In several cooperative projects we address the problems of unresolved phylogeographic patterns, cryptic species complexes and refugial theory within the framework of an integrative approach (molecular, ecological, bioacoustic, morphological).

 

 Atelopus

 

 

This research centres on such enigmatic and charismatic groups as Guiana Shield glass frogs (mainly Hyalinobatrachium spp.) Stubfoot toads (Atelopus spp.), Slender-legged treefrogs (Osteocephalus spp.), Fitzinger Neotropical Treefrogs (Dendropsophus spp.), and small Suriname toads (Pipa spp.)

 

 

 

 

 

 

Projects in collaboration with David Massemin (St. Laurent du Maroni, Fr. Guiana), Karl-Heinz Jungfer (Gaildorf, Germany), Miguel Vences (Evolutionary Biology, Technische Universität Braunschweig, Germany, and Santiago Castroviejo Fisher, Frost Lab, AMNH, New York, USA), Jörn Köhler (Hessisches Landesmuseum Darmstadt, Germany), Ignacio J. De la Riva (Museo Nacional de Ciencias Naturales, Madrid, Spain),

 

Alpha-taxonomy 

Cold-blooded Diversity
 

A. krokosua

These foul and loathsome animals are abhorrent because of their cold body, pale color, cartilaginous skeleton, filthy skin, fierce aspect, calculating eye, offensive smell, harsh voice, squalid habitation, and terrible venom; and so their Creator has not exerted his powers to make more of them
Carl von Linné, Systema naturae 1758


Well, more then one would expect. And an essential part of our work is therefore alpha-taxonomy, i.e. scientifically describing new species. These descriptions represent the backbone of modern biodiversity studies as in many cases the species is the unit of interest. Our field work has resulted in a number of new descriptions, among them some inconspicuous yet ecologically amazing species, such as the recently described cuckooing frog Allobates spumaponens. In this species, the male carries the tadpoles on its back and eventually drops them in the foam nests of syntopic leptodactylid frogs. This is the only case of interspecific brood parasitism in the entire animal kingdom, in which the male parent is the acting parasite.

 A spumaponens

Species described:

Bufo taiensis Rödel & ERNST, 2000. herpetofauna, Weinstadt, 22 (125): 9-16 (Amphibia, Anura, Bufonidae).

 Kassina schioetzi Rödel, Grafe, Rudolf & ERNST, 2002. Copeia, Lawrence, 2002 (3): 800-814 (Amphibia, Anura, Hyperoliidae).

Atheris hirsuta ERNST & Rödel, 2002. Herpetological Journal, London, 12: 55-61 (Reptilia, Serpentes, Viperidae).

Phrynobatrachus phyllophilus Rödel & ERNST, 2002. Journal of Herpetology, St. Louis, 36: 561-571 (Amphibia, Anura, Petropedetidae).

Acanthixalus sonjae Rödel, Kosuch, Veith & ERNST, 2003. Journal of Herpetology, St. Louis, 37: 43-52 (Amphibia, Anura, Hyperoliidae).

Allobates spumaponens Kok,& ERNST, 2007. Zootaxa 1555: 21-38 (Amphibia, Anura, Aromobatidae).

Arthroleptis krokosua ERNST, Agyei, & Rödel, 2008. Zootaxa 1697: 58–68 (Amphibia, Anura, Arthroleptidae).

Arthroleptis perreti Blackburn, Gonwouo, ERNST, Rödel. 2009. Breviora (Museum of Comparative Zoology) 515: 1-22. (Amphibia, Anura, Arthroleptidae). 

Paracontias kankana Köhler, Vieites, Glaw, KAFFENBERGER, Vences  2009. African Journal of Herpetology 58:98-105. (Squamata, Sauria, Scincidae).

Cyrtodactylus wayakonei Nguyen, Kingsada, Rösler, AUER, Ziegler 2010. Zootaxa 2652: 1–16. (Squamata, Sauria, Gekkonidae). 

Gekko canhi RÖSLER, Nguyen, Doan, Ho, Nguyen, Ziegler, 2010. Zootaxa 2329: 57. (Squamata, Sauria, Gekkonidae). 

Cyrtodactylus pageli Schneider, Nguyen, Schmitz, Kingsada, AUER, Ziegler 2011. Zootaxa 2930: 1–21. (Squamata, Sauria, Gekkonidae). 

Hyalinobatrachium kawense Castroviejo-Fisher, Vilà, Ayarzagüena, Blanc, ERNST, 2011 Zootaxa 3132: 1–55  (Amphibia, Anura, Centrolenidae)

Hyalinobatrachium tricolor Castroviejo-Fisher, Vilà, Ayarzagüena, Blanc, ERNST, 2011 Zootaxa 3132: 1–55  (Amphibia, Anura, Centrolenidae)

Allobates amissibilis Kok, HÖLTING, ERNST, 2013 Organisms Diversity & Evolution DOI: 1010.1007/s13127-013-0144-4 (Amphibia, Anura, Aromobatidae)

Dendropsophus counani Fouquet, Orrico, ERNST, Blanc, Martinez, Vacher, Rodrigues, Ouboter, Jairam,  Ron, 2015, Zootaxa, 4052: 44. (Amphibia, Anura, Hylidae)

Amietia moyerorum Channing, Dehling, Lötters, ERNST, 2016, Zootaxa, 4155: 1. (Amphibia: Pyxicephalidae: Amietia)

 

https://die-welt-baut-ihr-museum.de/en