16 September 2011

A pickup for slugs

Last Sunday we took a walk along a wooded park in a slightly rural area. Near the end of the park there were some isolated houses and in front of one of them was an old, dirty pickup truck.

I noticed some peculiar marks on the dust-covered hood of the truck.

On close inspection, they turned out to be slug feeding tracks.

These slugs normally graze on layers of blue-green algae (cyanobacteria, actually). But what was covering the hood of the truck didn't look anything like algae to me. It was for like a blackened crust of street dust. There must be something nourishing in it, though.

Here is another post about the discovery of slug tracks in an unexpected spot.


Cindy said...

They look a lot like snail grazing tracks to me. How do you tell them apart?


I can't tell them apart. I am assuming that they are slug tracks, because we don't have snails large enough to leave tracks like those around here.

Coyote said...

I have seen Lehmannia valentiana feeding on the pollen fallen from hollyhock flowers. Perhaps there is some pollen in all that other gunk.


Henk Mienis e-mailed this comment:

"In most cases the "blackened crust of street dust" consist of a sooty mold i.e. a microfungi which is breaking down honeydew produced by aphids and scale insects living on the leaves (in this case probably the foliage of the tree next to the pickup) above the black-covered objects."