Let’s take a look at some tracks and scat from an animal that is a sure sign of spring: Canada Goose (Branta canadensis).
Elsewhere in this blog, I’ve looked at classic bird tracks (called ‘anisodactyl’, with Crow, Raven, and Great Blue Heron as examples) and game bird tracks. (with Ruffed Grouse as an example). Today we have the third of five types of bird tracks: webbed (called ‘palmate’). Like game bird tracks, these have three long toes pointing forward and one short toe pointing back. The difference is they have webbing between each of the front toes (the webbing may or may not show in the track), and the small rear toe rarely leaves an imprint.
Just like the birds themselves, Canada Goose tracks are easy to identify (Photo 1). They are 4 to 4.75 inches long; no other PEI bird has palmate tracks that large. The next closest would be Greater Black-backed Gull, whose tracks top out at about 3.75 inches. Even if the webbing isn’t visible in the track, Canada Goose prints are distinctive.
Where you see Canada Goose tracks, you’ll see goose scat (Photo 2), as any golfers in the crowd will know all to well! Often found in piles, it’s cylindrical, typically two to four inches long, and a bit smaller in diameter than a finger. With birds, scat shape tells you a lot about their diet. Cylindrical scat points to a herbivore, which geese are. Carnivores and scavengers leave a splash; insect eaters’ scat tends to be larger at one end; fruit eaters’ scat will usually be coloured by the fruit; and seed-eaters leave deposits that are more loosely packed than those of plant-eaters.
Bird scat often has one white end (as seen here), or white throughout the whole deposit. Unlike mammals, birds don’t dissolve nitrogen-rich metabolic wastes in water to create urine. This has two advantages for the bird: no need to store water “on board”, thus keeping weight low for flight; and less need for fresh water, which is a benefit for birds that hang out in (or migrate over) salt water or dry habitats.
Instead of urine, birds produce a pasty, white substance - traditionally believed to be uric acid - that is excreted with their scat. It’s not particularly water-soluble, which is why it’s such a pain to wash off your car. I say “traditionally believed” as a recent study suggests the uric acid is actually processed into other compounds before being excreted. (Apparently bird pee is a hot research topic!). Regardless, white ends on bird scat are essentially urine, while the dark part is faeces. This two-tone appearance is a good indicator that the source was avian.
Scat can tell you a lot about who’s been around and what they’ve been eating. And there’s the added benefit of being able to tell people you really know your sh!t. It’s all part of PEI untamed!
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