Hi Benjamin - I'm afraid (admiting that this question lies outside my field of expertise) there's not much we can generalize here: all this probably entirely depends on the species under consideration? I know of long-distance migrating butterflies (both in the U.S. and Europe), but of course there are migratory birds; on the other hand, many (most?) insects (probably) usually fly only short distances, but non-migratory birds might, too. This lack in generalization is probably the reason for the lack in cross-taxon comparison?

Maybe you could profit from studies on bark beetles. The dispersal abilities of e.g. mountain pine beetles and Ips typographus have been studied in detail due to the economic relevance of these species.

Great question! As Martin suggested, it may be hard to generalize. I found a range of estimates for aquatic insects (i.e., the adult stages) in temperate areas, but most were relatively short (less than 1km). The stoneflies I studied flew on average ~200 m, which seemed like a long distance for a small insect (less than 1 cm long). There were some that flew farther, but I think these likely represent typical aquatic insects in that they are not known for particularly long or interesting migrations. There are some incredible anecdotes about dragonflies - e.g., long distance flights over the open ocean, butterflies, and some beetles, but certainly within each order there will be a huge amount of variation. Because tagging typical insects is generally more difficult than banding birds and other vertebrates, you may try looking into the genetics literature that uses population structure estimates to infer dispersal. That wouldn't be an ideal comparison, but it may help resolve the lack of direct dispersal measurements for many invertebrates.

I very much like Kate's suggestion re. looking at genetic population structure (we are currently doing this in a totally different context with soil invertebrates (which obviously seem to have an even smaller range) and will hopefully get some answers on inter-population exchange): with this tool (or information from literature), you may get some idea on migration being the basis for gene fluxes...

Thanks for the suggestions everyone!

I agree this is a great question. Regarding insect dispersal, there is evidence of mosquitos and biting midges being transported over pretty large distances by wind, though this might not be as relevant for ground-dwelling insects. We actually have some evidence of mosquitos carrying diseases to a near-shore island in Australia over a distance of 70km, so in certain areas (and for certain insect groups) this process shouldn't be ignored when trying to quantify dispersal potential!

Much of the following is migration focused, but you might want to see some of the following literature:

Hobson, K. A., Anderson, R. C., Soto, D. X., & Wassenaar, L. I. (2012). Isotopic evidence that dragonflies (Pantala flavescens) migrating through the Maldives come from the Northern Indian Subcontinent. PloS one, 7(12), e52594.

Hobson, K. A., Soto, D. X., Paulson, D. R., Wassenaar, L. I., & Matthews, J. H. (2012). A dragonfly (δ2H) isoscape for North America: a new tool for determining natal origins of migratory aquatic emergent insects. Methods in Ecology and Evolution, 3(4), 766-772.

Miller, N. G., Wassenaar, L. I., Hobson, K. A., & Norris, D. R. (2012). Migratory connectivity of the monarch butterfly (Danaus plexippus): patterns of spring re-colonization in eastern North America. PloS one, 7(3), e31891.

Rubenstein, D. R., & Hobson, K. A. (2004). From birds to butterflies: animal movement patterns and stable isotopes. Trends in Ecology & Evolution, 19(5), 256-263.

Dockx, C., Brower, L. P., Wassenaar, L. I., & Hobson, K. A. (2004). Do North American monarch butterflies travel to Cuba? Stable isotope and chemical tracer techniques. Ecological Applications, 14(4), 1106-1114.

Miller, N. G., Wassenaar, L. I., Hobson, K. A., & Norris, D. R. (2011). Monarch butterflies cross the Appalachians from the west to recolonize the east coast of North America. Biology letters, 7(1), 43-46.

Wassenaar, L. I., & Hobson, K. A. (1998). Natal origins of migratory monarch butterflies at wintering colonies in Mexico: new isotopic evidence. Proceedings of the National Academy of Sciences, 95(26), 15436-15439.

Chin, K. S., & Taylor, P. D. (2009). Interactive effects of distance and matrix on the movements of a peatland dragonfly. Ecography, 32(5), 715-722.

Jonsen, I. D., & Taylor, P. D. (2000). Fine‐scale movement behaviors of calopterygid damselflies are influenced by landscape structure: an experimental manipulation. Oikos, 88(3), 553-562.

Jonsen, I., & Taylor, P. D. (2000). Calopteryx damselfly dispersions arising from multiscale responses to landscape structure. Conservation Ecology, 4(2), 4.