NEW YORK — New York has gone to the dogs, but the rabbits and rhinos aren’t far behind in their assault.

With little fanfare, Gillie and Marc Schattner, married Australian artists, have marshaled their brash bronze menagerie up and down Avenue of the Americas from Greenwich Village to Rockefeller Center, along Astor Place and over to Downtown Brooklyn. Their anthropomorphic statues — genteel Weimaraners, ladylike hares and gymnastic wildlife — are leaving behind indelible paw prints in the duo’s covert conquest of New York sidewalks. And in the process, the Schattners have become the most prolific creators of public art in the city’s history, to the dismay of leading art historians.

“Nothing we’ve done has ever really been planned,” Marc Schattner, 57, said during a December Skype call from their studio in Sydney. Improvisation is a running theme for the couple, who first met on a shoot in Hong Kong (Gillie was the model and Marc the creative director) before eloping to the foothills of Mount Everest for a Hindu marriage just seven days later, jilting their respective fiancés.

Still, it’s a modest explanation for a pair who have received eight public art commissions on the streets since 2016 — an unprecedented pace for a city whose cultural programs come wrapped in streams of bureaucratic red tape. (It took Christo and Jeanne-Claude, by comparison, 30 years of efforts to win approval for “The Gates” in Central Park.) And in August, Gillie and Marc, as they are known, plan to unveil their most ambitious project yet, at Rockefeller Plaza: 10 “Statues for Equality” will depict powerful women, including Beyoncé and Angelina Jolie. The Schattners said that their project intends to highlight the gender gap in the city’s public statues, of which only 3 percent are of women.

Creating public art as a duo came years after the artists married in 1990. After living in Singapore and New York, the couple settled in Sydney, where they became weekend painters. Marc Schattner was working in advertising, with long hair and a Porsche. Gillie Schattner ran her own graphic design agency for 15 years. Their big break came in 2006 when they were finalists for Australia’s prestigious Archibald Prize for their portrait of the former Australian Olympic swimmer John Konrads and his dog.

The Schattners are now full-time artists with a thriving studio enterprise employing 10 in the heart of Sydney’s Alexandria neighborhood, with revenues of $5 million, they said. Their daughter, Jessie, 26, a photographer, works alongside them; their son, Ben, 23, is a composer and musician. And although the Schattners still paint, they are engrossed in their bronze statuary business. Their most popular subjects are “Dogman” and “Rabbitgirl,” autobiographical ciphers that represent the couple’s personalities.

“I’m the Dogman and she’s the Rabbitgirl, and we’re riding the Vespa together,” Marc Schattner told The Sydney Morning Herald. “I’m the person who will push to take more risks than Gillie. I’m the one who is always trying to make Dogman’s penis as big as possible.”

Such candor has not endeared everyone to the Schattners’ art, even when it’s motivated by feel-good causes like gender equality and, in the case of the white rhinos, wildlife conservation. Gillie grew up in Africa, where she watched “an elephant being killed before my eyes,” she said by email. “I vowed to do everything in my power to never let that happen again.” Marc spent time in Tanzania in his early 20s studying chimps. “If we weren’t artists we would be running a conservation reserve in Africa.”

Who says they can’t do both?

Citing Andy Warhol and Damien Hirst, the two define themselves as “popular artists.” “We’ve made terrible mistakes and have gone wrong in the past,” said Gillie Schattner, 53, explaining the fresh-faced pair’s path to success. “We’ve lost money and learned from that experience, but we’ve also learned by trying things out, failing, and then trying something different.”

“We want to make work that makes people smile,” said Marc Schattner.

Critics are frowning, however. One of Australia’s most prominent art critics, John McDonald, called the couple’s sculptures “impossibly tedious” and “gimmicky.” New York magazine’s senior art critic, Jerry Saltz, lobbed “bathos-infused folly” at “The Last Three,” the Schattners’ depiction of endangered rhinos arranged as a topsy-turvy column of Cirque du Soleil acrobats in Astor Place. The Schattners responded to his takedown with an open letter on their website defending kitschy art.

What has gone almost unnoticed is how the Australian couple conquered New York City, by eschewing the traditional gatekeepers of public art, like the nonprofit Creative Time and Public Art Fund, in favor of some unlikely allies: business improvement districts, or BIDs — public-private partnerships that oversee quality-of-life improvements funded primarily by assessments on property owners. From humbler beginnings as stewards of street sanitation, BIDs are evolving into cultural programmers, thanks, in part, to the pedestrianization of many New York streets in the late 2000s. However, critics point out that these new art presenters offer too few avenues for community feedback.

“This explosion of art, to my mind, is a lot of garbage,” said Michele H. Bogart, a professor of art history at Stony Brook University in New York, and the author of “Public Sculpture and the Civic Ideal in New York City, 1890-1930.” She considers the Schattners’ work “vapid” and “insignificant.”

There are 75 BIDs across the five boroughs. The Times Square Alliance was the first BID to commission temporary public art exhibitions, but recently, smaller BIDs have begun to recognize the correlation between public art and valuable foot traffic, according to Tim Tompkins, president of the alliance. “This is something happening on a huge scale, with the trimming of institutional and philanthropic funding for the arts nationwide,” he said.

Marc Schattner, whose persuasive charm and brimming smile recall the gifted salesmanship of Jeff Koons, explained, “With public art, you find a location and go for it.” In 2016, the Australian couple approached the Dumbo BID in Brooklyn for their first project, “Paparazzi Dogs” — a pack of bronze camera-toting Dogmen exemplifying the artists’ spectacle-driven signature aesthetic. The sculpture had previously toured Melbourne, Australia; Sydney; Shanghai and Singapore. Success in Dumbo gave the Schattners experience they could leverage when courting other BIDs for commissions.

But it wasn’t their art alone that beguiled William Kelley, the Village Alliance’s executive director, when the two offered “Paparazzi Dogs” to Greenwich Village that fall. The Schattners volunteered to self-fund the project, as they have with every public art commission they’ve done in New York. Kelley said he jumped at the chance. Less than two years later, the BID would also exhibit “The Last Three” (2017), billed on the Schattners’ website as “the tallest rhino sculpture in the world.” (The 17-foot-high stack currently resides at MetroTech Center, a BID in Downtown Brooklyn.)

It’s an open secret that very few public art organizations can afford what they commission. Costs are prohibitive because city officials demand work be weatherproof, graffiti-proof, damage-proof and accident-proof. Multiple permits are usually needed, and artworks must be approved by a city engineer. “The Last Three” cost $200,000, the Schattners said, which included fabrication, shipment, installation and de-installation. Even for a large BID like the Village Alliance, shouldering the costs of the single sculpture would eat 14 percent of its $1.4 million budget, which must also cover year-round expenses for street cleaning, public safety and business development for one of downtown’s busiest areas.

But art experts said the monetization of public art risked sequestering city space for only the wealthiest artists who could afford to bankroll their work — and saved taxpayer dollars at the expense of the field’s diversity.

“Why is it that one pair of sculptors in a city of thousands of thoughtful artists get chosen over and over again, if not that they have accumulated a reputation that is not necessarily based on the artistic merit of their work?” Bogart said. She added, “The problem with the BIDs is that they go with what’s familiar or think is popular.”

The boards of the BIDs that commissioned the Schattners are filled with real estate developers and business people.

“It’s like asking someone who isn’t a brain surgeon to operate on a brain tumor,” said Anne Pasternak, who led Creative Time, the New York-based nonprofit, for almost 25 years before becoming director of the Brooklyn Museum. “Professional advising is critical.”

Harriet F. Senie, a historian at the City College of New York specializing in public art, said the Schattners “would not be considered serious artists with a capital ‘A,’ and yet they have eight commissions? That’s a severe imbalance.”

And they could have had more. According to Tompkins, the Times Square Alliance declined multiple offers for sculptures from the Schattners. “My staff tells me they were very persistent,” he said.

Funding issues plague artists working within the municipal and nonprofit worlds. Jennifer Lantzas, the public arts coordinator for the Department of Parks and Recreation, who worked on nearly 60 exhibitions in the last year, said that artists must often privately raise money or ask their galleries to cover part of the costs.

“When we do ask for funding from the city, they can point to a very long and healthy career of not providing funds and still getting a great program,” she added.

“Let’s just say that the budget is never enough,” said Arlene Shechet, a leading ceramics artist whose first public art exhibition, “Full Steam Ahead,” is currently on view with the Madison Square Park Conservancy, a nonprofit whose commissions receive permits from the parks department.

Unwilling to go into debt herself, Shechet got creative; she entered a partnership with Kohler, which makes plumbing products, and worked for seven months at the company. She estimated that collaboration saved her $500,000 in labor and materials — all for a temporary project. (She would not reveal the exhibition’s final cost.)

“Certainly, artists who have resources have a greater chance” at public art commissions, Pasternak acknowledged, although she pointed out that artists without funding “make guerrilla actions all the time.” (Banksy is the best-known example of this approach.)

In 2016, the nonprofit Americans for the Arts convened its council of Public Art Network members from across the country to propose a list of 29 best practices for commissioning public art. One rule states that “any organization or entity commissioning artwork should pay artists for design proposals,” a stipulation that none of the four BIDs working with the Schattners followed.

By appealing to a BID’s bottom line, the Schattners may be setting a precedent for how BIDs work in the future, art experts say. After working with the couple, the Village Alliance created a public art program that requires artists to pay for their work’s “fabrication, installation, de-installation and site restoration,” according to a policy memo it sent to The New York Times.

Years of experience prompted the Australians to create their art loan program to woo interested organizations around the world. The artists’ website details their sculptures’ market value. They cite “Early Morning Coffee,” a 10-foot-tall sculpture of Dogman and Rabbitgirl at a Melbourne pier, as a case study of their success: 1 million impressions on social media, an increase in treasured foot traffic, 10,000 Instagram and Facebook posts.

RXR Realty, based in New York, is a happy customer. Michael Aisner, a vice president, said that the pair had been so “absolutely wonderful to work with” that the firm had greenlit five of their public art projects over the last year, from the financial district to Park Avenue. Come August, “Statues for Equality” will appear on its property at 1285 Avenue of the Americas, across from Radio City Music Hall. Aisner plans to wrap the Schattners’ female sculptures around the building’s colonnade like a gang of celebrity caryatids: a Meryl Streep here, a Michelle Obama there.

“I find art kind of off-putting and stodgy, but theirs is really friendly and engaging,” Aisner said. “You can sit down and have a coffee with their sculptures. You can’t do that with the Mona Lisa.”

The couple says they invest returns from their studio operation into their public art commissions, breaking even. Still, the Schattners find the money to travel the world for research trips and site visits, to Kenya, India, Shanghai and New York. Their expansive online catalog provides a cushion, offering nearly 1,000 items for sale. It includes 349 sculptures, 308 paintings, 196 prints, and jewelry and scarves recycling images from their public artworks. Prices range from $5.50 for an illustrated card to $520 for a tiger painting to a life-size version of their “Vespa Riders” bronze sculpture for $60,000.

The Schattners have been known to sell public art once it leaves the streets, though they say a majority of sculptures are donated to permanent spaces. “The Last Three” is set to go to the San Antonio Zoo in Texas this year after its run at MetroTech.

Bogart, whose three-decade career in public art includes a stint on the city’s Public Design Commission, sees the Australians’ self-financed investment plan as an evolution of an approach begun in the 1960s by Christo and Jeanne-Claude. Responsible for monumental installations like London’s “Mastaba” (2018) floating in Hyde Park and Central Park’s critically acclaimed “The Gates” (2005), the artist-couple would spend decades fundraising for a single project by selling smaller drawings and paintings.

The important difference between the pairs of artists, Bogart said, is the level of outreach involved. The Schattners consult with their BID partners, while their predecessors consulted with entire communities. “Christo would come to everybody and do courtesy reviews with everyone,” she said.

Indeed, lack of public oversight may have fueled the Schattners’ first New York fiasco, last February. The artists approached the Chinatown Partnership BID to bring their 900-pound “Dogman With Apple” (2017) statue to a square dedicated to Chinese-American veterans. The public artwork was fast-tracked by Wellington Z. Chen, executive director of the BID. But residents complained that the humanlike dog holding a red apple was “offensive in light of the long history of degrading caricatures of Chinese as dogeaters in American popular culture.” The artists were hit with a cease-and-desist petition signed by nearly 1,200 people, and the project was scuttled.

The Schattners said they were blindsided by the criticism, pointing out that the sculpture had been exhibited in Shanghai previously without complaint.

“Seventy-five BIDs have sponsored some 147 artworks,” Chen said. “Some are horrible. Some are ugly. But do you hear about them? No.”

Amy Chin, a community organizer in the neighborhood for 30 years who helped draft the petition, sees the issue differently. “Being public, art has to be responsive to its surrounding community,” she said in an interview. Chin added, “The BID had no public process installed because they thought the sculpture would be a gift to the community.”

But is this gift actually intended for residents, or for businesses? “Merchants are bleeding,” Chen said. “Even if it was a Donald Trump sculpture, I would put it out there if it would increase foot traffic.”

A majority of public art projects, including BID street art, must be approved by the Department of Transportation, the parks department, or both. These municipal agencies have boards and advisory committees that review submissions for permits, but Wendy Feuer, assistant commissioner for urban design and art at the Department of Transportation, acknowledges that the agency had no formal art program until 2007. “We were sort of inventing it as we go,” she explained. One mission “is quite frankly to put art on the streets of New York City,” Feuer added. Deciding what’s good or bad art is not in their mandate.

Tom Finkelpearl, the city’s commissioner of cultural affairs, conceded that “self-funding is an issue,” generally speaking, in the field of public art. But he added, “I don’t think the art ecosystem is broken; I think it’s quite healthy.” He pointed to his department’s $10 million commitment over the next four years for permanent public monuments, including a new statue of Shirley Chisholm in Prospect Park. They will be reviewed by a public design commission that includes artists, art historians and museum trustees.

“I haven’t seen a groundswell of opposition to what’s going on with the BIDs,” Finkelpearl said. “If I began to sense that people are upset, then we would look into it.” Such actions might include consulting the city’s Department of Small Business Services or commissioning a report.

For artists simply trying to bring joy into the streets, the Schattners feel as if the art world is disproportionately set against them. “We want to put a lot more heart into public spaces, more soul and humanity,” Marc Schattner said. Why should people be so opposed?

“Critics don’t speak for everybody and certainly not for the populace,” he added.

“Even if we get slammed, that wouldn’t touch me if I knew that the public enjoyed it,” Gillie Schattner said.

Besides, the two Aussies have much more ambitious plans for New York. They recently flew to Uganda to study the country’s endangered mountain gorilla population for their largest conservation sculpture yet. One day, they hope to install a gargantuan King Kong on the city’s skyline. Maybe their megasize ape will tower over Central Park. Maybe he’ll splay across Fifth Avenue. Gillie Schattner, with ambition in her voice, said the sculpture was in its early stages.

“But wouldn’t it be amazing for New York to save the gorillas?”

This article originally appeared in The New York Times.