Big Red has arrived and he’s shaking things up in my yard.

He dominates a single feeder or several if more are in his line of sight, he terrorizes every other hummingbird that attempts a sip, and he trills, unseen, within the foliage of nearby trees when he takes five from his vigilantism. This is not a discreet bird despite his less than four-inch length, and sometimes, Big Red is a she.

Backyard birders along the Wasatch Front are reporting unprecedented numbers of rufous hummingbirds at their feeders this year. Some hosts are reporting rufous hummers in their yards for the first time ever.

The phenomenon that brought the hummingbird windfall is likely the dry conditions and resulting subdued crop of wildflowers in high elevations through which the hummingbirds usually migrate. Rufous hummingbirds follow an elliptical migration path that takes them north through the Pacific lowlands as far as Alaska in the spring, and south through the Rocky Mountains in the fall.

They’re early migrants, and fall migration coincides with peak wildflower season. This year, however, the birds have to work harder to find nectar sources to sustain them during their passage to wintering areas in Mexico and beyond.

I knew Big Red had arrived in my yard when I heard his wing-trill. The sound is similar to the wing-trill of our broad-tailed hummingbird males, but not as metallic or loud. It’s decidedly thinner and buzzier and is identifiable to the rufous. My husband also noticed the new arrival and informed me with the pronouncement, “You’ve got a MEAN hummingbird out in the yard.”

And mean they are. And cantankerous. And bellicose. And militant. And I love it, especially at dusk when all the birds are gorging on sugar water at a frenzied pace to make it through the night.

Some mountain feeders are hosting so many hummingbirds of several species that the rufous have no choice but to put their cranky natures aside because they can’t defend the food source from all comers. I visited a campsite with three feeders last week. A single male successfully defended one of the feeders, a swarm of three species including two male rufous and at least four female rufous fed mostly in peace around a second feeder, and most of the birds avoided the third feeder.

Spending time in a hummingbird haven like that is like stepping into a beehive. The activity is mesmerizing, all the while inspiring thoughts of impending impalement as the tiny terrors zoom around the yard and around you, unafraid.

The males seem big and bold not only due to their demeanor, but also due to their color. Their rusty-orange stands out in a crowd of green and white broad-tailed, black-chinned and calliope hummingbirds, even though the males of those three species radiate a bright swath of color at their throats in the right light. And the rufous’ throat gorget seems to be the brightest of all, red coated with an iridescent dusting of orange.

Females can be just as aggressive as males and might defend a feeder or patch of nectar-producing flowers as well. Their behavior is a bit different, however; instead of only chasing away competitors, they may hover while flaring their tails threateningly to show off both the bright rust at the base of the tail feathers, and the flashy black and white at the tips.

Females differ in appearance in other ways as well; their back and wings are green, and they sport a triangular red throat spot and a rusty wash down the sides of an otherwise white breast.

I continue to hope an enduring cranky rufous of either sex finds my feeders like the one that stayed six weeks a couple years ago. She withstood no approach from others, she allowed no stolen sips and she gave no quarter. Watching her was some big-time summer fun.

It’s not too late to place hummingbird feeders in your yard even if you missed spring migration and longer-term breeding birds. The birds likely to use the feeders now are fall migrants moving southward and young recently liberated from nest sites. You might host new individuals every day.

Just remember to use a one-to-four ratio of sugar to water; wash the feeder with hot water and refill it every few days even if the birds haven’t used all the nectar; and don’t dye the water red. Those preparations just might attract Big Red to your yard, too.

Kristin Purdy can be reached at gobirding@comcast.net.