Moth Conservation
The Art and Science of Studying Moths
04/02/2024
The recording of moths is critical to the protection of these beautiful and important animals. Only by knowing where species are, where they are moving to and how their populations change over the longer term can we firstly recognise there is a problem and secondly figure out what we can do about it.
As many of our moths are largely nocturnal, this makes them more of a challenge to record and to understanding their ecology and distribution. Over the years naturalists have had devise ways to over come this.
Moths have been recorded for the than three centuries. Initially by observations and netting and by 1800 most of larger moths were known. “Dusking” involves netting moths on warm evenings and can still be very effective for some species. Beating bushes to find caterpillars and then rearing them to adulthood improved the understanding through the life cycle and identifying food plants. This is why so many of our moths, such as the Puss moth, thorns and tussocks are named after the caterpillar.
In 1842 a new technique to attract adult moths was discovered. Moths were found to be attracted to sugary substances and all sorts of concoctions of fermenting fruit and alcohol were tried to attract them. Wine roping and “sugaring” are still used to attract moths.
Artificial light technology improved in the 19th century with more powerful oil buring lamps which would attract moths. With electricity came more advanced and effective moth traps and by the 1930’s designs similar to those today were available.
The traps do not harm the moths but rather stores some of those attracted to the light until the they can identified, counted, recorded and then released. Light in the ultra-violet part of the spectrum is the most effective. Moths traps come in various shapes, sizes and bulb types. In recent years I have been experimenting with UV LEDs as a low energy and light weight alternative to fluorescent or mercury vapour bulbs. This has allowed me to carry traps further and into more inaccessible areas.
One off light trapping only tells part of the story, as moths, especially males, can fly long distances. A one-off record does not prove the species uses the area, but only through regular trapping of a location can a true picture of it’s moths be built up.
Moths can be searched for visually by day but this is difficult and often results in very limited records. To definitively prove a local population though involves larval searches. This requires painstaking investigations of known and potential food plants. Often finding the food plants of some specialist species can almost be as difficult as finding the larvae.
The information collected about moths is only of value when it shared, verified and collated to get the bigger picture of what is going on. It is vital that all records get passed to your county/regional moth recorder. In Ireland records can submitted via the MothsIreland website. MothsIreland
What is the analysis of all of these millions of records telling us?
Moths have been recorded for the than three centuries. Initially by observations and netting and by 1800 most of larger moths were known. “Dusking” involves netting moths on warm evenings and can still be very effective for some species. Beating bushes to find caterpillars and then rearing them to adulthood improved the understanding through the life cycle and identifying food plants. This is why so many of our moths, such as the Puss moth, thorns and tussocks are named after the caterpillar.
In 1842 a new technique to attract adult moths was discovered. Moths were found to be attracted to sugary substances and all sorts of concoctions of fermenting fruit and alcohol were tried to attract them. Wine roping and “sugaring” are still used to attract moths.
Artificial light technology improved in the 19th century with more powerful oil buring lamps which would attract moths. With electricity came more advanced and effective moth traps and by the 1930’s designs similar to those today were available.
Homemade LED UV Moth Trap on the Slopes below Fair Head. The white sheet helps with finding moths that settle around the trap rather than in it.
The traps do not harm the moths but rather stores some of those attracted to the light until the they can identified, counted, recorded and then released. Light in the ultra-violet part of the spectrum is the most effective. Moths traps come in various shapes, sizes and bulb types. In recent years I have been experimenting with UV LEDs as a low energy and light weight alternative to fluorescent or mercury vapour bulbs. This has allowed me to carry traps further and into more inaccessible areas.
One off light trapping only tells part of the story, as moths, especially males, can fly long distances. A one-off record does not prove the species uses the area, but only through regular trapping of a location can a true picture of it’s moths be built up.
Moths can be searched for visually by day but this is difficult and often results in very limited records. To definitively prove a local population though involves larval searches. This requires painstaking investigations of known and potential food plants. Often finding the food plants of some specialist species can almost be as difficult as finding the larvae.
The information collected about moths is only of value when it shared, verified and collated to get the bigger picture of what is going on. It is vital that all records get passed to your county/regional moth recorder. In Ireland records can submitted via the MothsIreland website. MothsIreland
What is the analysis of all of these millions of records telling us?