"It's not something we normally do, but we were actually looking for a larger alligator at this time," said curator David Wood.
Warminster animal control officer Craig Claycomb netted the beast, which is black and brown and about four-and-a-half feet long, according to Upper Moreland animal control officer Shawn Tarman.
It was just sunning itself on the rocky shore "minding its own business ... obviously a pet gone wrong," she said.
After they bound its jaws with medics' tape, Claycomb carried it in his arms "like a baby," and they put it in a carrier for a large dog, along with some wet towels.
"We don't really carry alligator equipment around here," she said.
"It was more docile than I would think a regular alligator in the wild would be," said Tarman. "I'm still not ready to do it again anytime soon."
In her year on the job, she's dealt with groundhogs ("tons of them"), snapping turtles and raccoons, but no other large carnivorous reptiles.
Last month, New Jersey wildlife officials searched Haddonfield's Hopkins Pond after some alligator sightings, but none surfaced.
Wood said the new resident is healthy and weighs about 30 pounds.
They won't know the sex, however, until a veterination conducts an examination next week. (Males have what's called a "hemi-penis," and a probe has to be inserted to draw it out, he explained. "If there's no hemi-penis, then obviously it's a female.")
Wood doubts that some heartbroken owner will come forward to claim the wayward critter.
"This was somebody's pet that they no longer wanted, or could take care of," he said. Gators get too big, and the novelty wears off. "They're not cuddly, they're not warm and fuzzy."
The zoo, which specializes in species from the Americas, has about 350 animals, including jaguars, bison, elk, and bighorn sheep.
"We have one of the nicest bald eagle exhibits you'll see in the country," he said.
Mullen delivered the gator at about 11:15 this morning, transporting in the comfort of a purple inflated kiddie pool in the back of his Chevy Suburban.
Soon it was being viewed by groups of schoolchildren and other visitors. It's even an added attraction for a special event this evening, a kind of family fun night.
(For more information on visiting the zoo, go to www.elmwoodparkzoo.org or call 610-277-3825.)
No word on whether the gator will be missed by a couple of other residents of the Mullen home: the king snake snared Saturday night in Upper Southampton and a tarantula taken from a Warminster house just yesterday.
"Three weeks ago, we had a 12-foot python but the kid came in and claimed it," he said.
Contact staff writer Peter Mucha at 215-854-4342 or firstname.lastname@example.org.