Wednesday, 31 October 2012

Helophilus trivittatus in 2012

2012 must surely go down as one of the oddest since detailed hoverfly recording started. It was spectacular because of its poor showing of many species, but there were high points. What was especially noticeable was the large numbers of eristalines seen at many localities. In some cases hogweed flowers were back to the state they were in during the 1980s - or at least they were in terms of Eristalis!

One species, Helophilus trivittatus, has occurred in exceptional numbers. It is a big brightly coloured hoverfly that obviously attracts attention from photographers as can be seen in Figure 1. The simple numbers in Figure 1 suggest a huge rise in numbers of records, but 2012 has also been an exceptional year for photographic records in which the level of recording grew by 33% in this one year. So, Figure 2, which shows the proportion of each year's records since 2004 is more representative.

Figure 1. Numbers of photographic records of Helophilus trivittatus from 2004 to 2012

Figure 2. The proportion of photographs of Helophilus trivittatus in each year from 2004 to 2012

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