Taxonomic Notes
Coenagrion vanbrink Lohmann, 1993 is considered a junior synonym of C. ornatum (Kosterin and Ahmad 2018).
Justification
European regional assessment: Least Concern (LC)
EU 27 regional assessment: Least Concern (LC)
Coenagrion ornatum is confined to streams, seepages and small streams nowadays nearly always found in an agricultural landscape. It ranges in Europe from eastern France and northern Germany, where it is often rare to very rare with rather disjunct populations and only few large populations, to southeastern Europe where it is more widespread and locally also common. In Slovenia, Croatia, Bosnia and Herzegovina as well as in other Balkan countries many new, also large to very large, populations are now known thanks to a slightly better field coverage from 2010 onwards. Nevertheless, further research is still much needed in this region and almost throughout the species' range. In Poland the species is very rare. Romania, Moldova, Ukraine and south European Russia are too under-surveyed to have a good insight if the species is indeed rare or just not observed. Its existence in Belarus needs to be confirmed. Its present Extent of Occurrence (EOO) and Area of Occupancy (AOO) are larger than any of the threatened category thresholds for criterion B. Thus, this species is listed as Least Concern for both European and EU 27 Members.
The main threat concerning C. ornatum are the increasingly intensive agricultural practices, leading to higher nutrient loads into slow-flowing waters and so to fastening habitat overgrowth by tall grasses and bushes, together with inappropriate renewal of ditches and poor management of bank-side vegetation. A decline in habitat loss in the future due to agricultural intensification and climate warming might occur, however this reduction is not expected to be severe over the next 10 years on a European scale. Flourishing populations still occur in many countries, but their survival is definitely incompatible with modern intensive agricultural practices. From the past decade, for C. ornatum there are no indications of severe decline in Europe apart from Poland.
As an Annex II species of the European Habitats Directive all member states of the EU27 must take the necessary measures so that the conservation status of the species is favourable, this includes the necessary conservation measures in and outside the Natura 2000 network. The need for systematic solutions and collaboration between landscape park management, water management and nature conservation authorities are emphasised to secure the species' stable populations and prevent its decline.
Member states of the EU27 must also set up monitoring schemes for the species, however at the moment it is not in place in all the members within the species' range (e.g., not in place in Slovenia and only being initiated in Croatia).
Further research into the species' ecology and biology is needed, together with distribution studies. Special conservation attention has to be given to populations outside the EU and on the border of species range, including Poland. The development of the species' population trends should be monitored, and if a change in a more negative direction occurs, a different assessment in the future may be relevant.
Geographic Range Information
Coenagrion ornatum ranges from eastern France and northern Germany, where it is often rare to very rare, to southeastern Europe where it is more widespread and locally also common, to Türkiye, the Levant, Iran and the Caucasian countries (Boudot and Kulijer 2015, Kosterin and Ahmadi 2018, Boudot et al. 2021). Most localities in the west and the north of its range are rather disjunct from the core range of the species, and it is unclear if this multiple fragmentation is natural or resulting from human activities. It seems that the species is rare or even absent from the mountainous areas in Europe.
In the European region the area where the species is reasonably widespread and locally common runs from Hungary and Slovenia southwards to Bulgaria, Türkiye and the Peloponnese in Greece. In Poland, it is very rare and severely endangered (Bernard et al.2009). The species went extinct in Switzerland (Boudot and Kulijer 2015) (unmapped). It was perceived extinct also in Italy, although on two recent occasions the species was rediscovered, with only a few or only a single adult imago recorded in the far south of Italy in Apulia (Mastropasqua and Liuzzi 2016) and in the northeast (Zandigiacomo et al.2020). It seems likely that the species is more present in the east of the Italian province Friuli Venezia Giulia as it has strong populations in the adjacent part of Slovenia (Vinko 2016). Romania, Moldova, Ukraine and south European Russia are too under-surveyed to have a good idea if the species is indeed rare or just not observed. Its existence in Belarus needs to be confirmed as the data are not reliable (Kitel 2022).
Population Information
Population trends for C. ornatum in most of its European range are unknown due to the lack of surveys, but the trend for the species seems to be more or less stable. In eastern France and in Germany populations are mostly small, but large populations are found in the Danube valley in Bavaria (southern Germany), and the Nièvre and Saône departments in eastern France (Boudot and Kulijer 2015). The area where the species is reasonably widespread and locally common runs from Hungary and Slovenia southwards to Bulgaria, Türkiye and the Peloponnese in southern Greece. Information on the population status is missing from Ukraine, Romania, Moldova and southern Russia. In the Balkans, new populations have been discovered recently, indicating that the species is more common and abundant throughout the region as previously thought. In Slovenia few large populations have been proven, or discovered, throughout the country, mostly in flatlands. During a short study in Central Slovenia conducted in 2013 on a 500 metre stretch of a single channel, over 2,000 individuals were marked, with estimated population size up to 7,000 individuals (Erbida 2016). The species seems to show an increase in Slovenia (Vinko et al. 2022) as well as in the rest of the western Balkans, and in the Czech Republic, although the results are not significant and are at least to some extent connected with an increase in surveys and the lack of species oriented studies in the past. In Germany, the species shows a moderate increase (Bowler et al. 2021), while for Poland a severe decrease was reported more than a decade ago (Bernard et al. 2009).
Habitat and Ecology Information
Coenagrion ornatum is a specialised species confined to small sunny brooks, streamlets and ditches, but also sunny seepage waters in peat- and marshlands with a thin water film. The species' habitat must have at least a slow current and moderately dense hygrophilous herbaceous vegetation, and in most cases there is organic mud and detritus on the stream-bed. The water, which is in most cases shallow, is often calcareous and relatively warm. Natural habitat types where these conditions occur are marshes with slow-flowing seepage waters, karstic springs and streams. Most of the European populations are however found in agricultural areas, at small ditches and streams, which are the species' secondary habitat. Many of these depend on both the cyclic cleaning of water courses and the mowing of bank side vegetation to prevent the habitat from becoming overgrown. In Slovenia and Germany, it was noted that the species readily colonises new suitable habitats. In most of its European range the species favours largely open habitats below 600 m, in most countries it inhabits plains and flats below 300 m asl. However, in the Balkan Peninsula populations have been found even up to 1,400 m asl.
Threats Information
At the moment, the species is not threatened on a European scale and there is no report of a species decline apart from in Poland. The main threat concerning C. ornatum is the habitat’s overgrowth, together with increasingly intensive agriculture and inappropriate renewal of species habitat (e.g. cleaning of ditches etc.) with large scale of clearance and mowing of banks during the species' flight period. Other serious threats in large parts of Europe for this highly specialised species are draining operations for intensive agriculture, habitat drying up and their destruction due to rainfall deficit and drought periods, swamp and soil drainage, water extraction and water table lowering through water abstractions, which will become even more important threats in the future due to global warming. Due to intensification of agriculture also water pollution has a high effect on species presence together with agriculture shifts from grasslands to ploughed fields, the worst situation being reached with maize (a crop that is irrigated throughout the summer months). Flourishing populations still occur in many countries, but their survival is definitely incompatible with modern intensive agricultural practices.
Use and Trade Information
There is no trade or use of this species.
Conservation Actions Information
Coenagrion ornatum is included on the Annex II of the European Habitats Directive and thus all member states of the EU27 must take the necessary measures for the conservation status of the species is favourable. The species must receive the necessary conservation measures in and outside the Natura 2000 network. In some areas, the continuation of soft cleaning of ditches in traditional agricultural landscapes contribute to the conservation of the species, but the application of hard cleaning technologies to brooks and ditches as well as the development of draining procedures to wet soils and grasslands destroy the habitat of this specialised species. Therefore, the suggested measures include cutting of overshadowing trees and bushes, timely adjusted mowing of overgrown vegetation in the ditches and on the banks and, finally, renewal of ditches with removal of vegetation that keeps the vegetation open and accumulated mud with excavators according to species habitat preferences. Intensification of agriculture should be avoided.
Conservation measures should also include expansion of water treatment plants, improved watercourse management as well as the preservation of good quality water resources. In areas that are embedded in the Natura 2000 network, changes in management plans must be made regarding use of water. Catchment management plans should be drawn up with particular attention to ecological flows in accordance with the European Water Framework Directive. This should mitigate or even prevent water abstraction for agricultural or domestic use from streams and ditches.
Member states of the EU27 within the species range must create and implement systematic monitoring schemes for the species. However, they are not in-place throughout all member states, even not in the species core distribution range, such as in Slovenia for example.
As the species is one of the least known Coenagrion species in Europe, further research on its ecology and biology is needed as well as population studies. As it is shown for Slovenia, Croatia and Bosnia and Herzegovina for example (although further research is still much in need there also), species oriented research resulted in better understanding of the species' distribution and in some cases provided information on several fairly large populations in the species' core range. Special conservation attention has to be given to populations outside the species core range.