BR. J. ENT. NAT. HIST., 7: 1994 



In the European context, the Ulex gallii/Calluna vulgaris heath is a scarce vegetation 

 type (NCC, 1989). 



Happily, in 1990, I found the grasshopper to be widely distributed over the 

 peninsula. Although most areas of maritime grassland and heath were occupied, 

 densities appeared to be greatest in the seaward half of the peninsula, and especially 

 around rocky outcrops. In the landward half of the peninsula, the grasshopper 

 occurred only along the eastern edge of the golf course, where maritime turf and 

 heath were restricted to a narrow strip of rocky outcrops and slopes above the shore. 

 Here, and elsewhere, the grasshopper occurred on the edges of cliffs and to within 

 several metres of high water. Evidently, the species is tolerant of vegetation receiving 

 considerable quantities of sea spray. However, in contrast to its occurrence in these 

 exposed conditions, the grasshopper was apparently absent from the golf course and 

 areas of tall grassland in the centre of the peninsula (including areas of former 

 arable land). 



Isolated colonies recorded previously (Burton, 1965) on the edge of the golf course 

 near Derby Haven could not be located. However, in some measure of compensation, 

 the grasshopper was found in a narrow strip of fore-dune (measuring roughly 200 m 

 by 20 m), sandwiched between the golf course and the shingle beach at Sandwick 

 in Castletown Bay (Fig. 1). This site represents the first record of S. stigmaticus 

 landward of the peninsula's narrow neck. 



Due to the proximity of Sandwick to Ronaldsway Airport, and the uncertainty 

 as to the species' origin on the island, the opportunity was taken to search the 

 abandoned Second World War hangar areas, runway aprons and grasslands within 

 the airport's perimeter. A careful search of the southern coastal fringe between Douglas 

 Head (OS grid reference SC382742) and The Chasms (SCI 92665) was also undertaken 

 (Cherrill, 1990). Both searches, conducted in July 1990, drew a blank, despite ideal 

 weather and seemingly suitable vegetation at many sites. The three other species of 

 grasshopper recorded from the island were widespread. Of these, M. maculatus and 

 C. brunneus were found to occur with S. stigmaticus on the peninsula and at Sandwick. 

 The third species, Omocestus viridulus (L.), was recorded in the vicinity of Derby 

 Haven in the late 1960s (Dr Garrad pers. comm.), but now seems to be absent from 

 the areas occupied by S. stigmaticus. 



Overall, my observations on the distribution of S. stigmaticus were encouraging, 

 with the species occurring more widely than was previously thought. Nonetheless. 

 closer consideration of the species' habitat requirements suggests that there may be 

 little cause for complacency amongst those seeking to secure the future of the 

 grasshopper on the Isle of Man. 



Habitat requirements 



In Continental Europe, S. stigmaticus occurs in a range of habitats, including sheep 

 pasture, moorland and woodland glades. However, only the driest, warmest sites with 

 short turf are occupied (Harz, 1975; Bellmann, 1988; van Wingerden & Bongers. 1 °S^; 

 van Wingerden et al., 1991a, 1991b, 1992). Hoist (1986) notes that S. stigmaticus 

 occurs at sites similar to, but warmer and drier than, those favoured by the congeneric 

 species, 5. lineatus. This observation serves to emphasize the curious isolation of 

 S. stigmaticus on the Isle of Man, because in Britain S. lineatus is restricted to Southern 

 England. Nonetheless, the ecological requirements of S. stigmaticus at Langness and 

 in Continental Europe appear to be broadly similar. 



My observations on Langness peninsula suggest that S. stigmaticus is never found 

 far from short turf (usually less than 5-10 cm tall) and reaches high densities only 



