Date: July 1, 2026

Time: around 2pm

Weather: hot and hazy.

Place: at a building site in Southern Guelph (Ontario, Canada) off Kortright Rd W. A map and the site are shown below.

Latitude: 43° 31′ 0.522″ N
Longitude: 80° 12′ 57.282″ W

Reference:
– [1] ‘Bird Tracks & Sign’, Mark Elbroch and Eleanor Marks, Stackpole Books (1st Ed.), 2001.
– [2] ‘Bird Tracks’, Jonathan Poppele, Adventure Quick Guides, 2023
– [3] ‘Tracks & Sign of Insects and other Invertebrates: A Guide to North American Species’, Charley Eiseman and Noah Charney, Stackpole Books (1st Ed.), 2010

Context:
The hot weather had begun to dry up the large area of standing water, exposing fine, damp sediment that was perfect for registering tracks. This photograph shows the level of detail preserved in the mud.

You can see some nice crow and killdeer tracks here.

Observations:
The first observation I saw was of a wasp collecting mud, which I knew was a mud dauber. They collect mud to use in the construction of their nests.

Here are some photos of the mud dauber itself.

In the second photo, there is also a nice coyote track. Zooming in, we can see the details that identify this species as a Yellow-Legged Mud Dauber Wasp (Sceliphron caementarium). Here is a close-up:

According to Wikipedia the yellow-legged mud dauber (Sceliphron caementarium) is a slender solitary wasp, roughly 2–3 cm long, with a mostly glossy black body, conspicuous yellow markings on the thorax and legs, tawny-brown wings, and an extremely long, threadlike waist connecting the thorax to the abdomen. Females gather wet soil from puddles and water edges and use it to build clusters of cylindrical mud chambers, often beneath eaves, bridges, rock ledges, and other sheltered structures. Each chamber is stocked with spiders that the female has captured and paralyzed, after which she lays an egg and seals the chamber; the larva consumes the stored spiders, pupates, and eventually emerges as an adult. Adults feed mainly on flower nectar and are commonly seen during summer. Although imposing in appearance, these wasps are generally docile, live independently rather than in colonies, and rarely sting people unless roughly handled (see here).

The sign that this wasp makes when it collects mud is described on page 445 of [3]:

“The black and yellow mud dauber (Sphecidae: Sceliphron caementarium) leaves conspicuous little digs at the edges of water bodies where it collects mud to use in its nests. In each trip to the collecting spot, it scrapes up a pea-size ball using its mandibles, holding it with its front feet. In coarser mud, this leaves an indistinct pockmark about 6 to 8 mm across, but in fine sediment, it shows up as a distinct cluster of paired mandible marks.“

The next set of observations was the tracks of a medium-sized bird, which is a Mourning Dove – the only common dove we have here in Southern Ontario.

The following is a screenshot from [2]:

The characteristics fit very well, particularly the size, splay, and short stride. According to [1, p. 64], the metatarsal registers only weakly or may be absent altogether, a feature visible in most of the photographs above.

Finally, I could not resist photographing the tracks of a raccoon. The level of detail in these tracks is amazing:

The claw marks in raccoon tracks don’t always register, but here they are very clear.

Final thoughts:
I’m amazed by how changeable and fleeting the tracking conditions are at this building site. As the standing water evaporates, it leaves a narrow ring of damp mud around its edge that is ideal for registering tracks. Once this mud dries, the tracks quickly deteriorate or crumble away. Then the next rainfall replenishes the water, and the cycle begins again.