Friday, August 2, 2013

National Moth Week

Last week saw the second, annual National Moth Week here in the US and CMBO was pleased to be a part of this great event for the second year. Insects have suffered from some pretty bad press over the years and, but for butterflies and dragonflies, most insect groups are still lumped here under the catch-all heading of 'bugs' and to most people bugs mean one thing - get the bug spray out!

But times they are a-changing and an interest in moths in the US has gone hand in hand with the publication of a new Peterson Guide on the subject (available at our store of course!). In the UK, a National Moth Night scheme has been running annually since 1999 and the amount of interest and knowledge of moths generated from this scheme has been spectacular. In the county of Norfolk, where I lived before moving to the USA, over 1700 species of moths have not only been identified by local enthusiasts, they have also been photographed, mapped and recorded for posterity. Long-running databases such as these are vital in providing solid background knowledge on the status of our natural heritage, so that important planning decisions can be made accurately and with due thought and process.

The current year has been relatively quiet for moths in our little corner of Cape May County and our catch for National Moth Week was much less than this time last year. With just two years of data, it is impossible to make much of this and my guess is that the wet and mild winter, followed by a wet spring, has had a temporarily negative effect on our moth populations. However, such natural events - if they turn out not to be a trend - often have short-term effects and populations should bounce back.

If interest in moths and other insects continues to increase in the US, in the way it did in the past in many European countries, then this can only be a good thing for the environment - which means it is a good thing for the planet, which means it is a good thing for us!! Here's a sampler of some of the moth species we identified on our National Moth Week session last week. Note that all moths were released alive after study.

Perhaps the classic idea of a moth - a grubby brown thing with little going for it! The Rustic Quaker is certainly uninspiring and was originally named a quaker for its austere appearance. This species is useful as a teaching tool however, as it clearly shows many of the wing features common to the majority of larger moths. This includes the positioning of the pale lines (often referred to as Antemedian and Postmedian lines) and the two circular marks on each forewing, known technically as the reniform (ie kidney-shaped) stigma and the orbicular stigma (rounded) [photo by Mike Crewe].

Common Looper is named after its caterpillar, which has a habit of forming loops with its body as it inches along. Many North American moths still await a useable English name and were originally named after their larval stages as these were recognized as pest species of agricultural crops or garden plants. This species is a member of a group known as the Plusias, most of which have extraordinary gold or silver blobs in the center of their forewings. Note also the long tufted hairs on the back which break up the moths outline and help it to escape detection from predators while at rest during the day [photo by Mike Crewe]. 

Though you may not know it, you will almost certainly have seen this species if you live in Eastern North America. This is the Isabelline Tiger, the moth that starts its life as a woolly bear caterpillar. Woolly bears vary in the amount of black versuses chestnut hair that they have and this is often taken as an indication of the hardness of the coming winter - sadly such old customs have no scientific foundation, but there can often be a long term trend in weather patterns that sees a certain type of winter following a certain type of summer. People who's lives depend on the outdoor world often pick up on these trends over time and the origins of such beliefs are always of interest [photo by Mike Crewe].

When you start getting into moths fully, you sooner or later have to decide whether you are going to take on the so-called Microlepidoptera. At just 4mm long, Homostinea curviliniella is a classic example of what is, quite frankly, a tedious little brown job! No-one has yet bothered to bless it with an English name, you won't find it in the new Peterson Guide and many people would probably lose the will to live before taking on the task of identifying it! However, all such things have a place in our world; this moth is in the Tineidae, a family of moths that mostly feed on dry remains and many started out as species that lived their lives feeding on the detritus in bird nests. Once Humans started settling into permanent homes, some species soon switched to munching our soft furnishings (after all, wool is just dead animal remains!) and became the moths that chewed holes in our carpets and clothing. Modern textiles and applications of moth repellents to materials has made these more or less a thing of the past and this little guy probably grew up in a bird nest and not in my CMBO T-shirts [photo by Mike Crewe].

A large and important family of moths are the tortrixes. The word tortrix means to twist, and these moths are named after the habits of their larvae, which twist up leaves to make feeding places that are safe from predators. This habit has resulted in many of them being known as leafrollers and this Sumacleaf Tortrix is typical of the group. Though small, many tortrix moths have intricate and interesting patterns [photo by Mike Crewe].

Tortrix moths come roughly in two forms - those that fold their wings tent-like (like the Sumac Tortrix above) and those that fold their wings flattened over the back. This Sulphur Sparganothis (the larva is known as Sparganothis Fruitworm) is typical of the flat-backed group and is an abundant species in Eastern North America. This is also a good example of a highly variable species and it seems that you never catch two that are quite alike, with many having a much more variegated look than this one [photo by Mike Crewe].

Micromoths come in an almost overwhelming amount of colors, shapes and forms. The Crambids and Pyralids form a large cluster of closely-related species which present an amazing array of variation. This Darker Moodna is in a group of Pyralids that rest with wings folded into a tube and many have attractive shades of mahogany and purplish brown on their wings [photo by Mike Crewe].

OK, so you can start by deciding whether you have a micromoth or a macromoth based on size... well, no, of course not, this is nature after all! This Common Spragueia is a so-called Macromoth, yet it is less than 10mm long. Though small, it is well worth seeking out as the colors and markings really are pretty amazing; it's a fairly common moth and its larvae feed on bindweeds [photo by Mike Crewe].

Many moth species are well-known for their cryptic appearance, an adaptation that allows them to successfully pass the day un-noticed by potential predators. The Juniper-twig Geometer is a classic example of a moth that readily passes itself off as a dead leaf. The strongly-hooked wing tips of this individual suggest that it is a female [photo by Mike Crewe].

Regular monitoring and recording of moths has demonstrated that many species move great distances as migrants, while others are local but still move around a surprising amount. The Waterlily Leafcutter (above) is one of an interesting group of Crambid moths that have aquatic larvae - the larvae feeding below water level on aquatic plants. Though tied to water for breeding, adults clearly move a lot in search of new breeding areas and in search of mates and this species is regular in our moth trap - though we have little or no suitable breeding habitat for it for at least a mile in any direction [photo by Mike Crewe].

This year's National Moth Week catch was a little quiet for us and there was little in the way of big and spectacular to post. However, we did catch a nice Ultronia Underwing. The underwings have cryptic forewings to keep them concealed during the day, but the hindwings are often brilliantly colored in red or orange. If investigated by a predator, the sudden appearance of this color when the wings are flicked open can be enough to startle the attacker and allow the moth to escape. In the past, the underwings were heavily collected purely for Human desire and some species have become much rarer than they once were. Thankfully we now live in times where 'collecting' for pleasure can be done with nothing more deadly than a digital camera. There is a wonderful natural symmetry about moths and it is a shame that the old Victorian tradition of pinning specimens in unnatural poses became so popular in the past [photo by Mike Crewe].

It's another year now until the next National Moth Week rolls around, but don't let that stop you from putting an outdoor light on in the evening, getting yourself a copy of the Peterson Guide to Moths and driving yourself crazy trying to identify the beasties that turn up. If you can't wait that long, don't forget that we often look at moths on our Sunday morning Belleplain Wildlife walks - so come aong and see what you have been missing!

Some of this year's moth group get stuck into the egg cartons [photo by Megan Crewe].