Western Conifer Seed Bug

Whilst the pectoral sandpiper at Filey and Monarch butterfly and lesser yellowlegs at Flamborough, may have claimed the attention, in respect to recent North American vagrants, over the past week, another North American species the Western conifer seed bug continues to gain a stronghold in the region, almost unbeknown. Although the westerly wind which have brought across the more notable species are unlikely to have contributed to its arrival in North Yorkshire. The species was initially reported from Italy in 1999, from where it spread rapidly across Europe. It is thought that the initial Italian find was due to animals imported with timber. Now the species readily breeds across Europe, each autumn sees an influx along the south coast of England.

I was lucky enough to find an individual in 2011, which symbolized one of the most northerly British records to data (in East Yorkshire). This year the trend has continued and the species remains, in the region (North Yorkshire). As their name suggests they are a species with primarily feeds on conifers. They tend to be closely associated with Scots pine Pinus sylvestris in Britain as well as lodgepole pine Pinus contorta, Corsican/black pine Pinus nigra and Douglas fir Pseudotsuga menziesii. It is reported to a lesser extent on spruce Picea and larch Larix. Like many insects (especially none-native ones) wintering sites involve buildings, large numbers of this species can group up and enter houses, where they spend the winter in loft spaces. Naturally bird nests, squirrel dreys and cracks in bark are used. It is perhaps in houses where they are most likely to be encountered, especially in the spring when they try to leave the hibernacula to breed. Nymphs of the species have been found in Britain indicating some breeding has occurred.

This species can be a significant pest to conifer plantations in the USA and Canada, however so far it has not exhibited any significant signs of damage to British nurseries.  FERA have monitored the species and seem unconcerned about its potential impact in Britain, subsequently there is no need to report sightings other than for ecological data recording purposes.    

  

With a basic knowledge of British shieldbugs Leptoglossus occidentalis can easily be separated from other species. It is notably quite large and elongate and has distinctively flattened hind tibiae. This specimen was recorded in North Yorkshire in a garden.