Insect & Other Invertebrate Tracks and Sign

Arachnids (spiders and scorpions) have 8 legs and therefore leave tracks with groups of 4 dots on each side of the trail. Sometimes it can be quite difficult to make out all 4 dots when the hindmost foot disrupts the marks from a previous foot.

Crustaceans (primarily crayfish and crabs here) have quite distinctive tracks. Crayfish walk primarily on 8 legs and have small claws at the end of their legs. If you look closely at their tracks you will find pairs of dots from each part of the claw. This is a very helpful characteristic for identification. Also look for two drag marks created by the sides of the tail. Crabs have 8 legs and walk sideways and leave a repetitive somewhat tire-tread like trail. Some species of crabs like horseshoe and hermit crabs leave distinct patterns that allow for easy identification.

Gastropods (mainly slugs and snails here) leave a number of signs including: slime trails, scats, and feeding signs. Slugs often feed on algae on tree bark and other surfaces and leave distinctive patterns in the process. Snail and slug scat forms long twisted ropes that are easily identified in the field.

Insects are an enormous group of animals. Insects that often leave tracks include: ants, beetles, crickets, grasshoppers, mantids, millipedes, wasps, and many, many more. Insects can be very difficult to identify from an actual specimen and identifying them to the species from tracks can at times be impossible. Sometimes the best we can do is identify to the order level.

Tracks & Sign of Insects and Other Invertebrates opened my eyes to an entire new world of animal tracking. Charley Eiseman and Noah Charney included an incredible amount of insect sign, from feeding signs to egg cases to scats. This guide is a valuable resource for anyone interested in learning about insects and it is a great way for trackers to expand their knowledge. These guys also have some great videos on identifying insect tracks and sign on their website.

Animal Tracks and Scat of California is a regional guide, but many of the species are found throughout North America. This guide includes mammals, birds, and even some reptiles, amphibians, and invertebrates. It is a great general tracking guide (full disclosure: I am a co-author of this guide) and is a great bet if you want a single guide that covers more than just mammals. This book includes some drawings of various insect and invertebrate trails.

Wildlife of the Pacific Northwest is a regional guide written by my friend and excellent tracker David Moskowitz. While this book primarily focuses on the Northwest, a lot of information applies nationwide. This tracking guide includes mammals, birds, reptiles, amphibians, and invertebrates. It dedicates 8 pages specifically to insects and other invertebrates at the end and has a really cool section on identifying beetle galleries created in tree bark. The guide also contains excellent original artwork by Dave and some incredible photography.