Project Results

Project Photo Highlights

Offal Wildlife Watching by the numbers

raccoon and Virginia opossum at gut pile

first year of image collection

fisher in snow facing camera

hunters who have deployed cameras throughout Minnesota since project inception

gut pile in grass field

gut piles filmed since project inception

adult bald eagles and crows feeding on deer carcass

different species captured on camera visiting project gut piles

black bear near gut pile

images collected since 2018

gray fox in snow passing in front of trail camera set up on tree trunk

Zooniverse volunteers who have helped identify and classify project images

Offal as Hunting Grounds

One of the best aspects of participatory science is that volunteers can observe and suggest things that are going on at gut piles that researchers might miss. One hunter volunteer suggested that there is more going on than just scavenging. Barred owls, for example, are recorded on many of the gut pile images. We know they are feeding on the guts themselves because we see this in several images. What’s interesting, however, is what might be attracting owls to this food resource. Owls detect their prey through sight and sound. Since gut piles aren’t moving or making noise, what is attracting owls to the gut piles? The volunteer suggested that perhaps they were hunting other scavengers. And lo and behold, we see this in some images! 

The question now is: are owls hunting rodents and getting a free meal of guts after, or do they find the gut pile and opportunistically use it to hunt rodents? We don’t just see this in owls, we have also recorded bobcats playing with captured rodents. 

Read the full publication here.

patterns of rodent and barred owl detections at gut piles throughout the day from OWW participant cameras. 

images of barred owls with rodent in mouth, hunting on ground
bobcat on hind legs with rodent in front paws

Dominant Wildlife at Offal in Minnesota Biomes 

diagram of the state of Minnesota with different biomes labeled

The graph below shows the proportion of images (not individuals within the images) in each biome that recorded a certain species group from 2018-2021. Each bar represents a different species grouping. Unsurprisingly, birds dominate most of the images we see. However, in the prairie, we see more carnivore images. Since the prairie region is pretty open, we expected birds to see gut piles quickly and dominate them, often before carnivores can even smell them, but the data shows carnivores are finding them quickly.