A disturbing turn of events has unfolded in New Zealand, where a predatory behavior by common mallard ducks has led to the euthanization of three individuals after they were found preying on vulnerable native chicks. This incident, occurring in the picturesque Mackenzie Basin of Canterbury, has sent ripples of concern through conservation circles.
Department of Conservation (DOC) rangers were alerted to a highly unusual and distressing situation when a member of the public provided photographic evidence of three mallard ducks actively hunting and killing freshly hatched pūteketeke (Australasian crested grebe) chicks. The scene was observed near Lake Alexandrina, a location south of Lake Tekapo, which is a known nesting ground for these native birds.
The pūteketeke, a species that garnered significant international attention in 2023 when it was famously crowned Bird of the Century through a campaign spearheaded by comedian John Oliver, is already classified as nationally vulnerable. This makes any threat to its young particularly concerning.
But here's where it gets controversial: Dean Nelson, a principal biodiversity ranger with the DOC, expressed his team's shock at the graphic images, noting that this predatory behavior is highly uncharacteristic of mallard ducks. "Mallard ducks usually eat plant material, with a little bit of protein from insects and snails during the breeding season," Nelson explained. "It was shocking to see them eating pūteketeke chicks. We went out there straight away and I observed three mallard ducks in the outlet creek where the grebe nests are." He further observed that the mallards were "actively scoping out the pūteketeke nests to see if they had chicks," while the adult pūteketeke, seemingly unaware of the danger, did not perceive the ducks as a threat.
And this is the part most people miss: This specific type of duck behavior was previously unknown to DOC experts. The concern is that such learned behavior could spread within duck populations. Nelson referenced a research paper from a Cambridge University scientist detailing a similar, previously undocumented case in Romania in 2017, where a group of mallard ducks were observed attacking and consuming chicks of two common bird species. This incident was also suggested to be a potential search for protein sources for egg-laying and nesting.
The individual who reported the behavior is commended for their swift action, providing crucial photographic evidence that allowed the DOC to intervene. "This is a great example of people taking action for nature and looking out for our vulnerable species," Nelson stated. He also highlighted that many people mistakenly believe the pūteketeke is an introduced species due to its name, when in fact, it is native and faces vulnerability.
The DOC emphasizes the importance of public engagement in conservation efforts, likening concerned citizens to "eyes and ears out 'naturing'" who can provide vital information when rangers cannot be everywhere at once. This sentiment was echoed in efforts to protect pūteketeke, as campers and boaties along Lake Benmore's shoreline were asked to remain vigilant over the summer period following reports of disturbed nests near the Ōhau C campground.
Many of these nests were situated in close proximity to the boat ramp and spread along the lake's edge. The pūteketeke colony in this area typically comprises 40 to 50 nests annually over the past five breeding seasons. This year, the birds had commenced raising their young later than usual in the outlet creek adjacent to Lake Alexandrina.
Following their observations, DOC staff successfully apprehended the three mallard ducks using nets and subsequently humanely euthanized them to prevent further harm to the native chicks. The department also planned to conduct further checks to ensure no other mallard ducks had adopted this concerning predatory behavior.
What are your thoughts on this unusual predatory behavior in mallards? Do you believe this incident highlights a broader, emerging issue within bird populations, or is it an isolated anomaly? Share your agreement or disagreement in the comments below.
