When the “pterodactyls” return to Colorado

When the herons return to Crane Hollow, Summer then will certainly follow, Their young are raised on nests of sticks, High in the trees they have their picks. Of places to roost year after year, And raise their young without any fear.

(With apology to Sally King)

By Greg Lowell Redstone Review

LYONS – Great blue herons are among the most dramatic birds we have here along the Front Range. Four to five feet tall with a wingspan of seven feet, their appearance in flight harkens back to prehistoric pterodactyls.

Among the most ubiquitous of North America’s wading birds, the great blue heron can be found in nearly every state from freshwater ponds and rivers to seacoast marshes and even beaches, where I once watched one stalk the Florida tidal wrack dodging sunbathers and swimmers.

They’re solitary birds, except when they pair up and nest every spring in large rookeries that are used year after year. Like the proverbial swallows returning to the same cathedral in Capistrano, blue herons gather every year in the same rookeries to mate, nest and raise their young.

Communal nesting

Locally, there’s a rookery off the misnamed Crane Hollow Road in Hygiene. Early settlers to the region incorrectly called the herons “cranes,” which suggests that there may have been a rookery there as long ago as the 19th century.

The Crane Hollow rookery can be seen from the road. It’s best to keep your distance from the rookery during nesting season for the benefit of the birds. Boulder County Parks and Open Space owns the land the Crane Hollow rookery is on, at the back of Pella Crossing Ponds, and enforces such protection. It also goes without saying that observers should respect the landowner opposite the rookery where birdwatchers have a vantage point.

Rookeries are a congregation of large, roughly built nests of sticks where the herons incubate their eggs and raise their young.

The nesting sites can’t be missed. The trees – generally large cottonwoods – are denuded from the constant rain of heron droppings, the ground underneath smells like week-old fish and the cries of the young birds have you looking for troupes of monkeys.

In Colorado, great blue herons usually lay one clutch of three to five eggs, which are incubated by both adults. The gloves, some sanding disks, a kitchen radio. and cackles hoping to be first in line for the adults’ fish or frog deliveries. eggs hatch in 25 to 30 days. For the next two months, the adults feed the young by regurgitation.

Time passed, and 166 items and 30,000 to 40,000 words later, our house, by some miracle, has avoided becoming a candidate for Storage Wars. Yes, there was a period that I could not quite reach my desk, due to the barricade of boxes. And when I handed over the yellow card at the Post Office, there would be a squeaking sound in the distance as an overflowing cartload of brown boxes rolled in my direction. But now, with the benefit of experience, when I see something that tickles my yearning itch, it must also have an immediate home and be something which is plausible to write about. Ceiling lamps that need a contractor and a room rewire are tedious to review, but a box of 72 red Sharpies is merely the work of a jiffy.

I’m not quite sure how to advise you if you would like to join the Vine gang. Buy some cheap items and write reviews about them. I wrote about 20 before being tapped on the shoulder. Be interesting and lengthy if necessary. There are screeds of really dull reviews out there, but it only takes a bit of thought to add some real value. Imagine an ordinary person like you or me, trying to decide which dog-proof chewable understuffed dragon they should buy.

Peter Butler was born in India and lived in a house facing a giant kapok tree. Growing up in England there were trees but never quite enough. After qualifying as biochemist there as a gradual evolution into being a graphic designer. He and his wife Deirdre moved to the States in 1997 and to Lyons in 2000. Finally there are enough trees.

While young herons can fly at 60 days, some of the more stubborn fledglings may stay as long as 90 days at the nest before departing.

The rookeries tend to be used continuously for many years, but the acidic excrement of the birds stresses the cottonwoods and causes them to lose their leaves, exposing the nests to marauding eagles. Then they will be abandoned, and a new rookery site will be established.

Empty nests in a rookery are commonly used by great horned owls, which breed earlier in the winter and who seem content to reside side by side with the herons.

While herons have always been in Colorado, the creation of ponds and reservoirs here along the Front Range has created an ideal environment for them and their numbers have increased. The birds are generally non-migratory, although they will come down to lower elevations in the winter.

What’s for dinner?

Everything Herons are commonly seen standing in ponds, marshes and streams peering intently into the water for fish, frogs and crayfish. The birds are patient hunters and move slowly and deliberately until they uncoil with lightning speed and thrust their bill into their prey.

As the young herons prepare to fledge, they can often be seen standing hunched over in silence at the edge of the nests until an adult approaches, at which point every one of the young in the rookery lets loose with shrieks

While fish and frogs are their primary food, they are opportunistic hunters and will also take turtles, rodents and birds. They’ve been seen stalking mice and voles in fields (and even prairie dogs here locally), raiding bird nests.

Night or day, herons will eat whatever comes their way.

Lyons’ resident Greg Lowell, is a former Lyons Town Board Trustee and serves as the chair of the Ecology Advisory Board.