Collection and Study of Spiders

Amateur and professional study of spiders is not as unusual as one might think, given the often negative press given to these interesting organisms. The American Arachnological Society has over 500 members and the International Congress of Arachnology at the Field Museum in Chicago drew nearly 300 Arachnologists, of which 40% were from outside the United States. Before serious study can be undertaken, a sample of the spiders involved must usually be captured, killed and preserved, so that a proper identification can be made. Exact determinations of species usually depend on details of the anatomy that are not easily observed while the spider is alive. It is then much easier to place living spiders in the same geographic area into their proper species. Collecting of spiders or any organisms can be complicated by local or national regulations designed primarily to protect endangered or threatened species or habitats. Because of this the potential collector should always seek permission to collect on land not his or her own. National Parks and Monuments are generally off limits, except under special circumstances involving professional research. Even this involves the application for and the actual receipt of special permits from the Interior Department. The United States Fish and Wildlife Service also has regulations in regard to collecting and may require a research permit. The United States Bureau of Land Management (Interior Department) and the United States Forest Service (Agriculture Department) may or may not require special permits and it is wise to check with their offices on the current regulations. These are being developed. State agencies may also require a permit, especially in state parks. In addition, private landowners should be consulted before entering their land to collect. Most people will not mind your catching a few spiders, but some may object and all will appreciate knowing who is on their land and why.

In addition, one should be aware of any federal or state endangered or threatened species (there are a few spiders on the lists, although so far none from the area covered by this site) and avoid damaging or killing these. Most spiders can be legally collected, given the conditions above. Even so it is a good policy to take only what you may need for study purposes, especially of very localized populations. Cave dwelling species are especially vulnerable and should probably not be collected unless an important study is involved.

Spiders can be found almost anywhere in the Southwest, from the very tops of high mountains to the low deserts only a hundred feet or so above sea level (and even below sea level in the deserts of California, just outside of our defined range). Capturing them can be as unsophisticated as using a wide mouthed peanut butter jar to more specialized, and sometimes expensive, traps, with most of the techniques being relatively inexpensive. Spiders can be found on the foliage of herbs, shrubs or trees, on or under the bark of trees and shrubs, inside dead trees, under ground, in leaf litter, on sand, gravel or rock surfaces (including cliff faces), under rock overhangs, along the edges of ponds, lakes, creeks and rivers, inside sheds, under rubbish, inside houses, under roof overhangs, under rocks and dead plants- in fact just about everywhere except open water.

Once collected, the spider should be examined while alive to make sure that it is adult. Male spiders have often complicated and swollen palpi while most adult females have a darkened and hardened epigynal plate on the anterior underside of the abdomen. Exceptions are found in female mygalomorphs, such as tarantulas, and haplogyne spiders, such as the violin spiders and spitting spiders. The females of these may have to be gauged by size to determine if they are adults. Immature spiders are usually difficult to determine to species, but sometime these are all you can get. The specimen, preferably adult, can be killed by dropping it directly in 70% isopropyl (rubbing) alcohol (or 75-80% ethyl alcohol if it is obtainable), freezing overnight in a freezer, or dropping the spider directly in water just off the boil and letting it cool to room temperature. All specimens should be stored in 70% isopropyl or 75-80 % ethyl alcohol. This should be changed if it becomes discolored. The container in which the specimen is stored should have a tight fitting lid or stopper. The use of neoprene stoppers has lessened because most of those on the market will deteriorate with age, leaching chemicals into the alcohol and becoming swollen and difficult to remove. For long term storage vials can be either stoppered, capped or stuffed with cotton and placed in old style canning jars with tight seals. The old rubber rings may deteriorate, however, and all storage containers should be checked periodically for leaks.

A specimen is of no value unless it has a label. The label is ideally made from some reasonably stable paper, preferably acid free, and either printed with a heat treating laser printer, a carbon-ribbon typewriter (rare these days), or by hand with a pencil (temporary labels only), or pen and India ink. Test any labels made with printers by storing them overnight in alcohol and rubbing them with a finger. Also, keep in mind that India ink should be allowed to thoroughly dry and that occasionally such inks will run. The minimum data are state, county, exact locality, date, and collector. It is helpful to also note the plant or habitat involved.