What critter in Walnut Creek is swallowing acorns and leaving evidence?

DEAR JOAN: We live in an area with a good variety of wild animals. Lately, I have found instances of scat containing several whole acorns. What animal would eat whole acorns and not be able to digest them?

— Tom, Walnut Creek

DEAR TOM: The thing about acorns is they aren’t intended to be digested whole, so any animal that eats them that way is going to expel them that way.

Some seeds, which are what acorns are, need animals to pass them through their digestive tract. The journey helps to break down the outer protective covering and make it easier for the seeds to germinate.

Acorns, however, don’t require that, relying on the animals for a different reason. The acorns are meant to be cached and buried, providing a moist environment that allows them to germinate, and offering some protection from being eaten right away.

Squirrels, other rodents and a variety of birds typically do the caching, storing the acorns to be eaten later when conditions soften the outer shell.

None of those foraging and storing animals are likely to eat the acorns whole, but there are larger animals that are known to scarf the acorns down.

The three most likely culprits are bears, wild boars and dogs. I haven’t seen any reports of bears wandering around Walnut Creek, but the area does have wild boars. Have you seen any damage in the neighborhood, such as plowed up lawns, broken fences or torn up garden beds? That would be a sign of wild boars.

If not, then the scat might be from neighborhood dogs. I love dogs, but let’s face it, most of them will swallow anything they come across whether it’s meant to be eaten or not. Coyotes, the dogs’ cousins, will eat acorns, but they don’t swallow them whole.

DEAR JOAN: I was wondering about bird droppings. I have noticed some large messy droppings in my backyard. Is this any indication that birds might have an illness?

They look like the birds, or whatever animal it might be, have diarrhea. I only have a hummingbird bird feeder, no other bird feeder. I also have a running fountain which I keep very clean. Any thoughts?

— Kathleen, Walnut Creek

DEAR KATHLEEN: The appearance of bird droppings changes with the season. In autumn, birds shift from an insect-centric, protein-rich diet to one higher in fat, eating more seeds, fruits and nuts. The goal is to pack on a little extra fat that will help keep them warm and nourished in the colder days of winter.

The splats are more likely to stain, but instead of being a sign of illness, they are a sign the birds are eating well. A sign I keep having to wash off my car.

Halloween alert

Every year birds, butterflies, lizards and other critters die after becoming tangled in those fake spider webs we like to use to make our homes look suitably spooky. Please don’t use them, and if you think you just have to, then put them up on Halloween and take them down the next day. The wildlife thanks you.

The Animal Life column runs on Mondays. Contact Joan Morris at AskJoanMorris@gmail.com.