Hi Jim -- they're probably tiny insects called "snow fleas" or "springtails" which are very active on warmer days in winter. Small, but VERY abundant - up to 300 million per acre in grassland habitats. They're not fleas, but of an order called Collembola. A quick reference from North Carolina State University offers: Life History & Ecology: The snowflea, Hypogastrura nivicola, is a dark blue collembolan that is often found on the surface of melting snow in late winter or early spring. The springtails are among the most abundant of all soil-dwelling arthropods. They live in a variety of habitats where they feed as scavengers on decaying vegetation and soil fungi. Most species are small (less than 6 mm in length) and quite susceptible to desiccation unless they remain in a moist environment. A unique, tube-like structure, the collophore is located ventrally on the first abdominal segment of most species. The exact function of this organ is unknown, but it probably helps maintain water balance by absorbing moisture from the environment. Springtails are named for a forked jumping organ (the furcula) found on the fourth abdominal segment. The furcula is retracted against the ventral wall of the abdomen and held there, in cocked position, by a special catch (the tenaculum) on the third abdominal segment. Releasing the tenaculum causes the furcula to snap down against the substrate and flip the organism some distance through the air. This device, present in all but a few genera, seems to be an effective adaptation for avoiding predation. Immature collembola are similar in appearance to adults. They usually molt 4-5 times before reaching sexual maturity, and continue to molt periodically throughout the rest of their life. Unlike most other arthropods, springtails appear to have evolved in a cool climate. Their relative abundance in the soil tends to increase as the mean annual temperature decreases and their development is most rapid under cool, humid conditions. _______________________________________________ Bob Hinkle Chief of Outdoor Education Cleveland Metroparks 11350 Broadway Ave Garfield Heights, Ohio 44125 (216) 341-9225 Interpretation is a mission-based communication process that forges emotional and intellectual connections between the interests of the audience and the meanings inherent in the resource. -----Original Message----- From: Ohio birds [mailto:[log in to unmask]] On Behalf Of James Dolan Sent: Wednesday, February 21, 2007 11:27 AM To: [log in to unmask] Subject: [Ohio-birds] More Interesting Robin Behavior Monday afternoon I got out for a walk in the woods. At one point I observed a Robin walking on top of the crusted snow. The bird was busy feeding on something, but there were no berry bushes or weeds around. As I looked closer, I saw that there were small insects walking across the snow. I don't know what kind of bugs they were,(I'm not an entomologist). The Robin was actually eating the insects. The bird would have to eat an awful lot of the bugs to get filled up. Has anyone else ever seen this? Jim Dolan ______________________________________________________________________ Ohio-birds mailing list, a service of the Ohio Ornithological Society. Our thanks to Miami University for hosting this mailing list. Additional discussions can be found in our forums, at www.ohiobirds.org/forum/. You can join or leave the list, or change your options, at: http://listserv.muohio.edu/scripts/wa.exe?LIST=OHIO-BIRDS Send questions or comments about the list to: [log in to unmask] ______________________________________________________________________ Ohio-birds mailing list, a service of the Ohio Ornithological Society. Our thanks to Miami University for hosting this mailing list. Additional discussions can be found in our forums, at www.ohiobirds.org/forum/. You can join or leave the list, or change your options, at: http://listserv.muohio.edu/scripts/wa.exe?LIST=OHIO-BIRDS Send questions or comments about the list to: [log in to unmask]