This study investigates the ecology of the Sandhill Rustic moth <i>Luperina nickerlii leechi </i>and its foodplant Sand Couch-grass <i>Elytrigia juncea. </i>The subspecies <i>leechi</i> occurs only at one site, Loe Bar near Helston in Cornwall, and hence is considered to be of high nature conservation concern. The population of this isolated colony is shown to be variable, with estimates for peak count numbers ranging between 69 (in 1991) and 746 (in 2000). The total area of <i>Elytrigia juncea </i>on Loe Bar varied during the course of this study between 11549 m<sup>2</sup> and 13930m<sup>2</sup>; not all of this area is utilised by Sandhill Rustic larvae. A strong female bias is shown (2.8:1 female to male) and the adult females show a clumped distribution. No moth was observed to move more than 349 metres, with females in particular crawling rather than flying; males are more active but rarely fly at wind speeds above 2.8m/s. Adult moths appear able to tolerate both high daytime temperatures (over 30°C) at high salinity levels on the exposed shingle near the sea. They are associated with the coarser element of sand and shingle present on Loe Bar, perhaps because the larvae can move more easily through the larger sand particles. Sandhill Rustic moths prefer the more vigorous <i>Elytrigia juncea </i>plants that occur near the sea; these plants have a large underground biomass (suitable for the larvae which spend 60% of their time feeding underground) and grow in large clumps joined together by extensive rhizomes along which the larvae can move. The conservation of Sandhill Rustics on Loe Bar depends in the medium term on controlling visitor pressure, maintaining habitat quality and increasing habitat size. In the longer term, Sandhill Rustics here are threatened by climate change, in particular sea level rise and an increased number of storm events.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:499731 |
| Date | January 2008 |
| Creators | Spalding, Adrian |
| Publisher | University of Aberdeen |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=25935 |
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