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On February the 25th, the Behavioural Ecology Group was visited by Dr. Jürgen Ott (see below for details). Jürgen Ott has worked for several years on a wide range of topics, all related to conservation. These include landscape planning, management plans, river restoration, monitoring studies, environmental impact assessment, limnological studies, urban ecology, environmental education and climate change. Mostly, he uses populations of damsel- and dragonflies as flag species. Please feel free to have a look at the abstract of Jürgen Ott’s talk in our group (below).
We, the Behavioural Ecology Group, pride ourselves on the rise of our newest research avenue: the conservation of Mexican rivers, streams and wetlands. Up to this moment, most of the studies carried out by us, concentrated on basic, hardcore science. Nonetheless, we are conscious of the growing problems imposed by climate change, global warming and in general, human activities, on all natural habitats. Therefore, since we firmly believe that research groups can team up together, pursue a common goal and learn from each other, we seek to create research, monitoring and conservation plans that will be applied in Mexico. The visit of Jürgen Ott to our group is the first step into the consolidation of a formal collaboration between our groups.
I thank Jürgen Ott for this unique opportunity.
M. A. Serrano-Meneses
Behavioural Ecology Group, coordinator
Jürgen Ott
L.U.P.O.GmbH, Friedhofstr. 28, D-67705 Trippstadt, Germany – ott@lupogmbh.de
University of Landau, Dep. Of Environmental Sciences, D-76829 Landau
Approximately two decades ago, a strong change in the distribution patterns of European dragonflies started and this process is still ongoing – presently even again increasing. Firstly, Mediterranean species were moving to the north invading central and northern Europe (e.g. Coenagrion scitulum, Erythromma viridulum, Crocothemis erythraea, Anax imperator, Aeshna mixta, Aeshna affinis), and recently also African species were invading Europe and presently expanding their ranges rapidly (e.g. Trithemis kirbyi, Selysiothemis nigra).
These trends are mainly the result of the changes in the abiotic factors “temperature” and “precipitation”, altering the biology of the species as well as of the biotopes. E.g. the higher temperature in the waters leads to more generations: an example is Ischnura pumilio in Germany, becoming now bivoltine and having also bigger populations with stronger tendencies to expand in new waters.
Furthermore, the lack of water due to the reduced precipitation in some areas leads to strong changes in the biocoenosis: mainly moorland and alpine species (e.g. Somatochlora arctica, S. alpestris, Aeshna juncea, Leucorrhinia dubia, Coenagrion hastulatum) are negatively effected by drying out of their biotopes, as well as species of springs and small rivulets (e.g. Cordulegaster bidentata). As a result of this process the moorland species are losers of these climatic changes and remain on the Red Lists and some are even in higher rankings.
The ubiquitous and euroecious species (Anax imperator, Libellula quadrimaculata and L. depressa, Ischnura elegans) on the other side are the winners. This process also leads to a change of the whole coenosis in the waters, as not only the composition of the dragonfly fauna changes: the effects are registered in all taxa resulting in a general change in the food webs and biodiversity of the waters.
Presently a new threat becomes more and more important: Alien Invasive Species (AIS). As a consequence of the globalisation, introductions by aquarists and fishermen many new species can be found in the waters. Some of them also do reproduce and are increasing their ranges, out of these species some are having negative – some even dramatic – effects on the biocoenosis.
In particular some fish (e.g. Ctenopharyngodon idella) and crayfish species (e.g. Orconectes limosus, Procambarus sp., Procambarus clarkii) could be identified as dangerous for the native dragonfly fauna, as they are altering the biotic conditions or the food chain (e.g. reduction of water plants – lack of substrate for oviposition) or as they are strong direct predators for the larvae.
As these AIS often are favoured by higher temperatures, both factors now may have synergistic and cumulative effects. After a short review on recent developments and trends of the distribution and ecology of Odonata in Europe the possible consequences for nature conservation and the future for native dragonfly populations are outlined.
We, the Behavioural Ecology Group, pride ourselves on the rise of our newest research avenue: the conservation of Mexican rivers, streams and wetlands. Up to this moment, most of the studies carried out by us, concentrated on basic, hardcore science. Nonetheless, we are conscious of the growing problems imposed by climate change, global warming and in general, human activities, on all natural habitats. Therefore, since we firmly believe that research groups can team up together, pursue a common goal and learn from each other, we seek to create research, monitoring and conservation plans that will be applied in Mexico. The visit of Jürgen Ott to our group is the first step into the consolidation of a formal collaboration between our groups.
I thank Jürgen Ott for this unique opportunity.
M. A. Serrano-Meneses
Behavioural Ecology Group, coordinator
Abstract: Climate change and Alien Invasive Species (AIS) - a deadly cocktail for dragonflies?
Jürgen Ott
L.U.P.O.GmbH, Friedhofstr. 28, D-67705 Trippstadt, Germany – ott@lupogmbh.de
University of Landau, Dep. Of Environmental Sciences, D-76829 Landau
Approximately two decades ago, a strong change in the distribution patterns of European dragonflies started and this process is still ongoing – presently even again increasing. Firstly, Mediterranean species were moving to the north invading central and northern Europe (e.g. Coenagrion scitulum, Erythromma viridulum, Crocothemis erythraea, Anax imperator, Aeshna mixta, Aeshna affinis), and recently also African species were invading Europe and presently expanding their ranges rapidly (e.g. Trithemis kirbyi, Selysiothemis nigra).
These trends are mainly the result of the changes in the abiotic factors “temperature” and “precipitation”, altering the biology of the species as well as of the biotopes. E.g. the higher temperature in the waters leads to more generations: an example is Ischnura pumilio in Germany, becoming now bivoltine and having also bigger populations with stronger tendencies to expand in new waters.
Furthermore, the lack of water due to the reduced precipitation in some areas leads to strong changes in the biocoenosis: mainly moorland and alpine species (e.g. Somatochlora arctica, S. alpestris, Aeshna juncea, Leucorrhinia dubia, Coenagrion hastulatum) are negatively effected by drying out of their biotopes, as well as species of springs and small rivulets (e.g. Cordulegaster bidentata). As a result of this process the moorland species are losers of these climatic changes and remain on the Red Lists and some are even in higher rankings.
The ubiquitous and euroecious species (Anax imperator, Libellula quadrimaculata and L. depressa, Ischnura elegans) on the other side are the winners. This process also leads to a change of the whole coenosis in the waters, as not only the composition of the dragonfly fauna changes: the effects are registered in all taxa resulting in a general change in the food webs and biodiversity of the waters.
Presently a new threat becomes more and more important: Alien Invasive Species (AIS). As a consequence of the globalisation, introductions by aquarists and fishermen many new species can be found in the waters. Some of them also do reproduce and are increasing their ranges, out of these species some are having negative – some even dramatic – effects on the biocoenosis.
In particular some fish (e.g. Ctenopharyngodon idella) and crayfish species (e.g. Orconectes limosus, Procambarus sp., Procambarus clarkii) could be identified as dangerous for the native dragonfly fauna, as they are altering the biotic conditions or the food chain (e.g. reduction of water plants – lack of substrate for oviposition) or as they are strong direct predators for the larvae.
As these AIS often are favoured by higher temperatures, both factors now may have synergistic and cumulative effects. After a short review on recent developments and trends of the distribution and ecology of Odonata in Europe the possible consequences for nature conservation and the future for native dragonfly populations are outlined.
