Friday, September 21, 2012

Red Veined Darter at the Quarry

Female Red Veined Darter, Sympetrum fonscolombii
Human activity often leads to dramatic changes in our landscapes (1). These changes in turn can lead to often irreversible damage to our freshwater habitats. The building activity in Ireland during the boom in the 2000's involved drainage and development of sites that directly and indirectly lead to the destruction of many of the countries wetlands habitats. The crazed excesses of the so called "Celtic Tiger" are not wholly to blame however, as wetland destruction has been a feature of the Ireland's changing ecology for some years. For example the extensive wetland complex located around the Douglas and Tramore rivers near Cork city was replaced with the municipal dump for over 20 years. Such destruction generally leads to a homogenisation of biodiversity and the local extinction of many plants and animals (1).
Ballyhemiken Quarry
However this is not always the case. Sometimes human induced changes on the landscape have a positive effect on biodiversity. A prime example of this is unused quarries. When in use, water entering these sites is drained or pumped away. When no longer in use, this water is allowed to collect, forming wetlands that are not naturally present on Ireland (2). One such site is located in Ballyhemiken, a townland about 17 km from Cork city center. Unused for a number of years, this quarry has many shallow pools that provides the perfect habitat for odonates. A number of species have been recorded here, namely Beautiful Demoiselle (Calopteryx virgo), Emerald Damselfly (Lesta sponsa), Variable Damselfly (Coenagroin pulchellum), Common Blue Damselfly (Enallagma cyathigerum), Common Bluetip (Ischmura elegans), Large Red Damselfly (Pyrrhosoma nymphula), Migrant Hawker (Aeshna mixta), Emperor Dragonfly (Anax imperator), Four Spotted Chaser (Libellula quadrimaculata), Ruddy Darter (Sympetrum sanguineum), Black Darter (S. danae) and Common Darter (S. striolatum) (2).
Shallow Pond at Ballhemiken Quarry
On a recent visit to the quarry I was lucky to spot several Red Veined Darters (S. fonscolombii). This is a rare sighting for Ireland, as it is only seen here as a migrant, and seldom at that with only twenty records for Ireland, mostly near the coast. As far as I can tell, the record reported here is the westernly most sighting for S. fonscolombii in Ireland. All individuals were female, and two consecutive visits showed no males. They were very wary and took to wing upon my approach, flying a short distance before alighting on the surrounding Yellowworts, mint, low growing willow, Reed Mace and rushes. When undisturbed, the females congregated around shallow pools, some of which had dried up.
Female Red Veined Darter, Sympetrum fonscolombii
There are no record of S. fonscolombii ever breeding in Ireland, however in Britain there has been an increase in numbers breeding. It is predicted that Ireland may follow suit and the numbers of sightings may increase in the future (3).
Female Red Veined Darter, Sympetrum fonscolombii

  1. Dolný and Harabiš, 2012. Biological Conservation 145 pp. 109-117
  2. Nelson and Thompson, 2004. The Natural History of Ireland's Dragonflies p. 391
  3. Nelson and Thompson, 2004. The Natural History of Ireland's Dragonflies pp. 301-305

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