For the lovelorn, Ichaboe and Spheniscus are a couple to envy.
When they reunite after even a short time apart, they call out to each other. They bow in greeting. They slap bills tenderly. She is lovely, her plumage a riot of white and black, her sole adornment an identification band of purple and white tastefully wrapped around her rubbery right wing. He is strapping and bold.
The two African penguins have been together a year, and the glow has yet to fade. They were so enthralled with each other one morning last week that they paid no attention to the New England Aquarium biologists watching the couple’s displays of affection atop Island 2 of the penguin exhibit.
The scientists are more than mere voyeurs. They are trying to save a species that researchers predict will be extinct in the wild in 15 years.
It is not only important that these penguins mate, but that they mate with the right partner, to maintain as diverse a gene pool as possible in captivity.
To ensure that, the aquarium biologists become the matchmakers, arranging marriages between pairs most likely to succeed and snuffing out romances that are not meant to be.
This means they must constantly monitor the love lives of their 10 breeding couples, which the aquarium says is one of the country’s largest collections in captivity.
“We can keep the species alive by making love happen,’’ said Caitlin Hume, whose official title is senior penguin biologist, though it could also be Cupid-in-chief.
Not long after she said this, a young female climbed onto Island 2 and noticed Ichaboe. The female dropped her head to the side and puffed her cheeks and waited for the male to respond. The intruder got so close they touched. Spheniscus turned on the upstart and brayed in protest. But what about her man? Would he stand by her?
Ichaboe rose to his full 2 feet and joined his bride to bray his disapproval. The interloper was rebuffed. This time.
Penguins enjoy a reputation as nature’s model of monogamous devotion, adorable creatures willing to waddle endlessly across the barren expanses of Antarctica on behalf of their mates and chicks. Ain’t no ice sheet cold enough to stop ‘em.
But African penguins are a different sort of bird. They live off the coast of South Africa and Namibia, nowhere near the South Pole. They might choose mates for life, but they might also cheat if their partners show up late during mating season. They might dump a partner if they just don’t like the match.
“There are some breakups in the penguin world as well; that way they are a little like people,’’ Hume said, wading with penguins in the salty waters of the exhibit last week.
African penguins, also known as beach donkeys for their bray-like call, used to be abundant. In 1956, researchers counted 147,000 pairs of African penguins, Hume said. In 2008, only 28,000 of the species were found.
The culprits seem to be overfishing and changes in ocean currents; the schooling fish that African penguins fancy are farther out to sea. The chicks are completely dependent for their first three months, so the adults take turns hunting.
Nowadays, adults need to travel twice as far to bring back food. The chicks and the adults left behind are going longer without sustenance.
None of these obstacles exist in the friendly confines of the aquarium, where the 54 African penguins are fed a steady diet of ocean smelt, sardines, capelin, and herring. The islands are scrubbed clean every day. The 150,000 gallons of Boston Harbor water are constantly filtered.
The staff tries to match penguins that are least likely to be related. The easiest way to do this would be to find mates that do not have a long history in captivity and that bring some new genes to the penguin pool.
But because of their diminished numbers, the aquarium no longer removes African penguins from the wild, and ensuring genetic diversity is becoming increasingly challenging.
Once a match has been approved, the couple is moved to a more intimate setting downstairs. “Candlelight and romance,’’ Hume calls it. If the penguins hit it off — and they usually do, according to staffers — that is where they hatch and raise chicks.
But sometimes, penguins go looking for love in all the wrong places. Hume pointed out Plum Pudding and In-Guza, two African penguins who were preening on Island 3. They got together on their own, but because their genes are bad for breeding, the aquarium did not let their eggs hatch.
“Sometimes we take a pair that found each other and we have to separate them,’’ Hume said.
And sometimes when one door closes, another opens.
It happened to Harlequin, an 18-year-old female, and Durban, a 16-year-old male, who were on the rebound when they met 11 years ago; the staff had separated them from their original mates. In what should have been their sunset years, they have instead become the most prolific of the aquarium’s African penguin couples, having raised six chicks in three breeding seasons.
As Hume passed, Durban sidled up to Harlequin and bowed, penguin-ese for “I’m so glad that I found you.’’
African penguins normally live 10 to 15 years and are ready to breed by the time they are 4 — Spheniscus’s age. Ichaboe is 5.
And then there is Alfred, who is 36. The old-timer has good genes, so the aquarium put him together with 9-year-old Treasure.
There was some doubt whether she would go for the older bird, but she did.
Then again, the quarter-century age difference has worked for Michael Douglas and Catherine Zeta-Jones. Why not Alfred and Treasure?
“He’s a lucky guy,’’ said biologist Andrea Desjardins. “They’re a very good couple.’’
David Filipov can be reached at filipov@globe.com. 
