For several years, kōtare, our native kingfishers, have been turning up at West Auckland rehab centre BirdCare Aotearoa with a mysterious affliction: mouths laced with tiny, almost translucent worms. “It sort of looks like strings of saliva sticking between the roof and the bottom of the mouth,” says Catriona Robertson, a hospital manager at BirdCare. “It’s almost like threads of fibreglass.”
Sometimes the worms are still incubating, and the only sign of infection is opaque blisters inside the kingfishers’ mouth. Watching them hatch is “quite hectic”, Robertson says. “Makes your skin crawl.”
BirdCare sent a box of frozen kingfishers to parasitologist Bronwen Presswell at the University of Otago. She has just identified the worms as a new species, naming it Skrjabinoclava pharyngophila. Presswell has identified dozens of other parasitic worms, or nematodes, carried by our native birds. This is a favourite. “They’re just kind of pretty; they’ve got lots of detail. Some nematodes are just tubes, basically, but these guys have got lots going on.” She admires the spines that run the length of their bodies, and the “cordons” that wrap around their heads like bridles, and she’s fascinated by the fact the worms have so far been found only in North Island kingfishers—and only in the mouth.
Removing them is not so pretty. Worming medications typically target the gut, so are not effective. Instead, says Robertson, it’s a job for fine-tipped forceps. “It takes a decent amount of force—it is quite surprising how much you really have to tug on it to get them to detach.” As each worm releases, she says, it makes a “rather alarming” audible pop. (Presswell says the “pop” occurs even when both worm and bird are dead. The worms’ heads are encased in a transparent cap and she suspects they burrow this in, making removal a bit like yanking apart dome fastenings on a raincoat.)
The tweezer sessions can be stressful for the small birds, even with pain relief. Some, carrying heavy loads of worms, need multiple treatments. But afterwards, the birds often perk up, Robertson says—they’ll start eating more, which can be critical to their survival.
She hopes that learning more about the worms could help the team find an effective medication. For now, though, it’s worm by worm: pop, pop, pop.
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