Great blue herons make a comeback
Anna Juraschek, sculling coordinator for Community Rowing, spends a lot of her life on the Charles River. From March until December, she’s on the water seven days a week. Coaching others and rowing herself, she knows every curve in the river from Watertown Falls to the Museum of Science. On a typical morning, Juraschek arrives at the Brighton boathouse before dawn.
“The time that I see them the most is between 5 and 7,” said Juraschek, talking about great blue herons.
Impressively large, great blue herons stand 4 feet tall and have a wingspan of 6 to 7 feet. An adult has a blue-gray color, with a black stripe across its eye area. Despite their size, adults weigh only about 6 pounds because herons, like other birds, have hollow bones.
When Juraschek spots a Great Blue (as they’re often called), it’s usually standing stock still in the shallows, looking for fish to impale with its daggerlike bill.
“Every time we see one, we stop. If we get too close, it will take flight,” Juraschek said. A Great Blue flies with arched wings and slow wingbeats. Its cry is a deep, hoarse croak, sounding something like fraaaank! “They don’t sound like any other birds,” Juraschek said. “They don’t look like any other birds.”
“A lot of people row because of the proximity to nature,” said Juraschek, who has worked at Community Rowing since 2004. Growing up near the Charles in Dedham in the 1980s, her parents didn’t let her play along the river. “They considered it pretty dirty,” she said. “I didn’t see any wildlife. It was pretty gross.”
After the passage of the Clean Water Act in 1972, cleanup efforts slowly began along the Charles.
“Over the years, the birdlife has become more and more plentiful,” Juraschek said. Besides great blue herons, she often sees ducks, cormorants, swans, green herons, black-crowned night herons and the occasional bald eagle.
Jennifer Hochschild, political science professor and one of the amateur racers whom Juraschek coaches, sees a heron almost every summer day. “They’re emblematic of the river,” said Hochschild, whose team calls themselves The Herons.
“It’s kind of magical. You can’t see them from the road, but we’re in this space along the river where we see all kinds of things,” Juraschek said. “You forget that you’re in a city.”
Great blue herons are a common sight along the Charles these days and were common in colonial times, but 30 or 50 years ago, they were a rarity in Cambridge.
The Great Blue’s decline was due to several factors, including a craze for feathered hats that began in the late 1800s. A steady supply of feathers was needed for the fashionable hats, creating a hot market for plume hunters who slaughtered hundreds of thousands of birds, some nearly to the point of extinction. The snowy egret was a prime target; so was the great blue heron.
That was until 1896, when two Boston socialites, Harriet Hemenway and Minna Hall, persuaded their wealthy friends to boycott feathered hats. That year, the two cousins helped launch the Massachusetts Audubon Society.
In 1913, Congress passed the Weeks-McLean Law, also known as the Migratory Bird Act, which outlawed spring hunting and prohibited interstate transport of migratory birds. The bill was sponsored by Massachusetts’ John Weeks and Connecticut’s George McLean. The Migratory Bird Treaty Act of 1918 replaced the Weeks-McLean Act, making it illegal to capture, possess or cause harm to protected birds or their nests or eggs. The list of protected birds, which includes the great blue heron, was updated in 2020.
The Migratory Bird Act helped quell the slaughter of birds. It would take a state referendum to restore great blue herons to the Charles.
“It’s all about beavers,” said Wayne Peterson, who has worked for Mass Audubon since 1988 and is director of the Massachusetts Important Bird Area Program.
Once plentiful, “beavers were practically extirpated through North America as a result of trapping,” Petersen said. “Up until 50 years ago or so, beavers were scarce in Massachusetts.”
In 1996, a Massachusetts ballot initiative to ban leg-hold and body-gripping traps passed with overwhelming support from eastern and urban areas of the state. The change in legislation changed the state’s landscape. Since then, “the increase of beavers has been prodigious,” Petersen said. They “are significantly more common than they were when I was a kid.”
Beavers often build their lodges in ponds they create by damming streams in wooded areas. The trees in the newly created pond will die, but some remain upright for years. Tall dead trees surrounded by water is ideal nesting habitat for Great Blues, who build their nests high in the leafless branches. The water below deters racoons and other terrestrial predators from raiding nests for eggs or hatchlings.
Great Blues usually nest in colonies (also called rookeries or heronries) ranging in size from a few mating pairs to several hundred. Usually several eggs are laid in a nest made of sticks, and after about 28 days, hatchlings emerge. Young herons can fly in about 60 days and leave the nest at about 90 days.
In Massachusetts, most Great Blues nest inland. The herons flying along the Charles may have hatched in rookeries in nearby Andover, Middleton or Boxford.
“They only use the colonies during the nesting season,” Peterson said. Though some overwinter in Massachusetts, in the fall most migrate to Southern states or further south. “They typically start to arrive back in Massachusetts in March,” Petersen said.
“Beavers really are master builders,” he continued. “Over time they’ve altered the landscape in lots of ways that ultimately are perceived to be very positive over the long haul. The great blue heron is one of the principal beneficiaries. There are lots more around now than there were 30 years ago.”
“Being here made me a birder,” said Al Parker, a security guard at Mount Auburn Cemetery who leads bird walks. He’s been on the job for 16 years, patrolling and exploring the 175-acre burial ground and botanical garden.
“He’s been here since I started,” said Parker when I met up with him at the cemetery in early May. “He’ll leave in the afternoon and come back early morning. Some days you’ll go without seeing him, and some days he won’t leave. He’ll just hang out the whole day.”
Parker was referring to “the resident heron,” a Great Blue often spotted nabbing fish out of Mount Auburn’s several ponds. Though herons feed mainly on fish, their diet may also include frogs, snakes, salamanders, insects and small rodents. Parker has seen the resident heron hunt a chipmunk.
Outside of mating season, Great Blues are usually solitary and will secure a feeding area, defending it against others of their species.
We walked to the pond-size Halcyon Lake, but the heron wasn’t there, so we followed paths across the cemetery toward Willow Pond.
Great blue herons, Parker explained, are blue around mating season and turn a paler, grayish color during winter. We agreed that they look ancient, like a pterodactyl or some other dinosaur bird.
Approaching Willow Pond, we heard the mating calls of male toads. We reached the pond, but still no heron. Our time was almost up. Parker was apologetic that the heron hadn’t appeared. As we stood on the bank, other birders approached Parker to share recent sightings. Suddenly, he pointed across the pond. “There he is.”
The resident heron was standing at the pond’s edge, tracking something in the water. It struck in an instant, spearing a koi with its bill, then tossed the orange fish between its beak until it was straight enough to be swallowed. Down it went.
Just as quickly, the heron struck again.
“Another orange,” Parker said.
The heron swallowed again, then flew across the pond, its wings flapping slowly, its sticklike legs trailing. It landed close to where we were talking. The heron seemed uninterested in the people nearby.
A minute later, ignoring all social distancing rules, the resident heron walked within a yard of us, the gaze of its golden eyes fixed on the shallows. I was astonished – this wildness so close I could almost touch it – but to Parker, it was a common occurrence.
“He put us into a scare last year,” Parker said. “It looked like there was a cloth wrapped around his bill. We had Animal Control; we had Watertown Police. We tried to catch him. He was feeding and kept pushing the rag back. He could fly, so we couldn’t do anything. Finally, the rag just fell off.”
Herons in distress
When a great blue heron is in trouble, Christina Correia, director of the Cambridge Animal Commission, usually gets the call, but those calls are rare.
“If I had to guess, I would say one every three years,” Correia said. “We get a lot more loons and geese and swans than we do herons.”
How do you rescue a 4-foot great blue heron with a 6-foot wingspan?
“Every situation is different,” Correia said. “At Fresh Pond, when one had fishing wire aggressively wrapped around his head and beak, the Animal Rescue League came out and did a water rescue. We don’t have the equipment or boats to get out on the Reservoir.”
“It took us a while to catch him because he was thriving. Then, as he started to decline and became weaker, we were able to catch up with him. Usually when they’re sick or injured, they’re not acting as they would when they’re healthy. When they’re injured, it’s usually a broken leg or a broken wing, but there have been situations in which they’re entangled in something and just need to be untangled.”
Correia and her team have responded to an injured Great Blue near Jerry’s Pond and picked up one or two along the river. “Sometimes we have to use nets. Sometimes we’ll use something as simple as a sheet to drape right over them.”
Once captured, a heron is placed in a large dog crate. “They’re better off in something that’s enclosed,” Correia said. “It’s less scary for them.” The crate is loaded in a van and usually taken to Tufts Wildlife Clinic in North Grafton.
“Once the vets there see them, they determine if it’s a rehab-able and releasable injury or if the bird needs to be euthanized. That’s not our call,” Correia said.
If the bird can be treated and brought back to health, “they might call us back and ask if we want to be a part of the release,” Correia said. A recovered bird is released at the same spot where it was captured.
Heron rescues are rare, said Correia, who’s been on the job for 25 years. Usually when she encounters a great blue heron, it’s feeding along the Charles or flying over Fresh Pond.
“I love when I see them,” she said. “I definitely see a lot more than I used to.”