Moths Count Newsletter 2013
Total Page：16
File Type：pdf, Size：1020Kb
Moths Count Ne wsl etter 2013 15 million moths and counting... The National Moth Recording Scheme (NMRS) database continues to expand; since last year’s newsletter we have received an additional 1.3 million moth records taking the grand total to 15,532,135. Eighty-four vice-county (VC) datasets have been received over the past year, 25 of which are still to be imported into the database. Two important Brimstone Moth (H. McDonald) additions to the NMRS database were 6,473 records for the Isle of Rum and 23,967 additional records from NMRS data continue to be used by our conservation partners Cumbria and Westmorland, filling in significant previous via the National Biodiversity Network (NBN) Gateway. We are gaps in coverage. Once all of these datasets have been also collaborating with academic institutions following requests imported to the NMRS, the online species distribution maps for NMRS data to investigate land-use and species distribution (viewable at www.mothscount.org ) will be refreshed. change. The NMRS data were used as corroborative evidence to support moth population trends in The State of Britain’s There has been no change in the top three vice-counties; Larger Moths 2013 report which was published in February South Hampshire (853,836 records), Hertfordshire of this year, see page 04 for further details. (620,665 records) and Dorset (610,414 records) have the largest datasets. In the NMRS database as a whole Some preliminary analysis of the NMRS data has been 36% of records are historical (pre 2000), however, two-thirds happening ‘in-house’. A sub-set of data (46 VC datasets of vice-county datasets have a lower proportion of historical with comprehensive annual coverage) from the NMRS records than this and, more worryingly, seven VC datasets were compared to look at the mean number of records still do not contain any historical records at all. This is a per vice-county from 2000 to 2012 (figure 1). >> great shame as there can be no assessment of distribution y 9000 t change over time for any moth species in these counties n u o c 8000 while this situation remains. We really need to improve the - e c i v 7000 historical baseline of the NMRS! Historical data from the r e p s 6000 John Heath/Biological Records Centre scheme were sent d r o c e 5000 r to County Moth Recorders (CMRs) several years ago, h t o 4000 yet some of these data have still not been incorporated m f o r 3000 into VC datasets. e b m u 2000 n e g 1000 a The picture is similar for the Rothamsted light trap network r e v data. Once verified by CMRs, all these data will be extremely A 0 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 valuable at both VC and national level. We know that we have Year a relatively comprehensive dataset in the NMRS for 2000 Figure 1: Average number of records per vice-county in the NMRS onwards, so by 2020 we will have a 20 year data run that for the 46 vice-county datasets with comprehensive annual coverage. will lend itself more easily to data exploration and analysis. 02 Moths Count Newsle tter 2013 >> This shows a general increase in the number of records 10,000+ 5,001 to 10,000 over time, presumably due to factors such as improvements 1,001 to 5,000 in data flow and increasing numbers of people involved 501 to 1,000 301 to 500 in moth recording. The best years in terms of the average 101 to 300 number of records were 2006, 2010 and 20 11. The density 1 to 100 of records at 10km resolution for 20 11 can be seen right in figure 2. In 20 11, the top five most widespread moths at 10km resolution were; Large Yellow Underwing (58% of recorded squares); Dark Arches, (55% of recorded squares); Figure 2: Density of 2011 records per 10km Brimstone Moth (53% of recorded squares); Silver-ground in the NMRS database. Carpet (51% of recorded squares) and Flame Shoulder (50% of recorded squares). Figure 3 shows the number of species recorded per VC and Northern Ireland to-date in the NMRS database. From the map it appears that some areas such as the East Midlands and Cornwall are less species rich than you would expect, however, this is an artefact of lack of data in the NMRS rather than moths. Unsurprisingly, given the weather, the number of moth records per VC dipped last year and may fall further when the 2013 data are collated. Until the recent spell of hot sunny weather, moth abundance and species richness were considerably lower than in previous years across most of the UK. In addition to this species flight periods were delayed. Last year’s wet summer followed by the recent long cold > 99 101 to 200 winter and late spring, the coldest for 50 years, are likely 201 to 300 301 to 400 to be contributory factors. 401 to 500 501 to 600 601+ It will be very interesting to look at long term changes in distribution, abundance and species richness over time. However, in order to do this we need annual updates of vice-county datasets. It is clear from the coverage gaps in Figure 3: Number of species recorded figure 2 that not all VC datasets are up to date. As reported per VC and Northern previously, we encourage all CMRs to submit their datasets Ireland to-date in the NMRS database. to us by 31st March each year. It would be great to receive all moth data from the previous year to enable some simple analysis and provide feedback on the most recent recording season to the moth recording community in this annual newsletter, and to enable effective moth conservation at local and national levels. The NMRS is not just about producing distribution maps; it is an amazing resource that has many potential applications. Many recorders note the abundance of all the moth species that they catch in their traps and many CMRs are keen to capture such information. At the simplest level, abundance information can provide important information for conservation by revealing the presence of breeding colonies of species, whereas a species record without abundance might just be a single vagrant individual. 03 So, in an ideal world, we would like to encourage everyone to record the numbers of moth species that they see and Moth Night 2013 CMRs to capture this level of information in their VC datasets. Moth Night 2013 will run from 8th -10th August, including However, we recognise that this is not always feasible both day time and nocturnal sightings. This year’s theme e.g. trapping at night with a lamp and sheet; or necessarily is ‘the tigers’, a group of large, colourful moths that are a priority for some moth recorders. In some cases it is not experiencing mixed fortunes in the UK. The Garden Tiger, practical to count every single Large Yellow Underwing, well known for its ‘woolly bear’ caterpillar is a severely so in instances such as these, perhaps an estimate of declining species; the day-flying Jersey Tiger, on the other abundance could be recorded. Just because a species hand, is expanding its range rapidly in London and southern is apparently common and widespread now doesn’t mean England. Both trends may be driven by climate change. that it will be in the future! The NMRS provides us all with The Ruby Tiger will also be on the wing across the UK an excellent opportunity to add value to the masses of moth during Moth Night. data that are recorded. Collecting abundance data over a long time period may enable us to determine population All three of these species are spectacularly beautiful and trends for moths as well as distribution patterns, and to will prove popular at public events, converting even the most assess whether populations are stable, increasing or ardent moth sceptic. To find details of events local to you decreasing at a national and regional scale. please visit the Moth Night website www.mothnight.info or if you are running an event please submit the details Many people do record species abundance already and to the website. such information is captured in the VC datasets and NMRS. For example, in the NMRS database there are 162,831 Moth Night is the annual records of Garden Carpet. Only 1,452 (0.9%) of these celebration of moths and records do not have a figure for abundance. Ninety-two moth recording run by percent (150,264) of Garden Carpet records are from sites Atropos and Butterfly which recorded Garden Carpet in more than one year. Conservation, in association There are 379 repeatedly trapped grid squares with detailed with the Centre for Ecology Garden Carpet records for nine or more years. We are & Hydrology. You don’t now undertaking statistical examination of how these data have to focus on the tiger compare with trends from more systematic recording moth theme; feel free to schemes such as the Rothamsted Insect Survey light-trap pursue your own target network. We will keep you posted on this and any other species or venture to interesting discoveries based on the NMRS dataset. different trapping sites. An aim of Moth Night is to raise awareness of moths and moth recording and, most importantly, to have fun! Please submit your results via the online system www.mothnight.info . Online data submission is the only way that we can sustain Moth Night as we do not have the resources to deal with the vast array of recording formats that were previously received.