species of the week # 58 – ornate bluet
The only breeding water known in Rhineland-Palatinate at present is located in the Bruchbach-Otterbachniederung in the Southern Palatinate. Here the species occurs in large populations.
|Distribution status||Threatened with extinction|
|Last sightning in Rhineland-Palatinate||current|
|Habitat||Sunny, clean streams and ditches in grassland|
|Threat||Mown banks and embankments, overfertilisation, drought|
As a warmth-loving species, the ornate blutet inhabits slow-flowing, sunny, shallow but permanently water-bearing ditches and streams that are warm in summer and winter, mainly in grassland areas.
With a length of about 3 cm and a wingspan of up to 4.8 cm, the ornate bluet is a relatively small dragonfly species. However, it appears somewhat more compact overall than other species of the Coenagrionidae family. The male is a strong blue colour with black markings. A special feature is a black “U” on the second abdominal segment, which is probably meant to remind of the erect wings of a bird.
Both too intensive ditch clearing or extensive mowing of the embankments and adjacent grassland as well as failure to maintain the ditch or fallowing of the surrounding grassland affect the population. Other causes of endangerment are also groundwater lowering with summer drought and strong sediment and nutrient inputs as a result of intensification of agricultural use, for example through grassland conversion.
– Establishment of wide riparian strips over the entire area.
– Preservation of grassland in riparian areas
– Halting climate change
Photo: By Christian Fischer, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=50334055