Experts delighted after capturing rare footage of unlikely creature: ‘Surprise guest’

For a few electric minutes on a quiet morning in southern China, a seldom-seen waterbird stole the show. Wildlife watchers at Huguangyan Scenic Area in Zhanjiang, Guangdong recorded rare footage of a scaly-sided merganser — also known as the Chinese merganser — marking the first documented appearance of this endangered duck at the volcanic lake reserve. The “surprise guest” sent ripples of excitement through the conservation community and offered a hopeful sign for regional river habitats.

With its sleek crest and distinctive dark-edged white patterning along the flanks that looks almost like scales, the scaly-sided merganser (Mergus squamatus) is a master of fast, clear rivers bordered by intact forest. It is also famously elusive, which makes any confirmed sighting noteworthy. Brief as it was, this encounter expands understanding of the bird’s seasonal wanderings and suggests that stretches of cleaner, calmer water remain within reach in parts of Guangdong.

Why this bird matters

The scaly-sided merganser is globally classified as Endangered, with best estimates placing its total population in the low thousands. Such small numbers heighten the importance of each piece of habitat it uses. Because this duck is sensitive to disturbance and requires clean, well-oxygenated rivers with natural banks and vegetated islands, its presence often signals a relatively healthy waterway. In other words, if the merganser feels at home, the river is likely doing many things right — from supporting aquatic insects and fish to buffering floods and filtering pollutants.

Signals from a living river

Huguangyan is renowned for its mirror-still crater lake and surrounding greenery, but it is also connected to wider regional waterways that shape the area’s ecological character. The merganser’s brief stopover underscores how vital undisturbed riparian zones are: overhanging trees for shade, fallen logs and natural banks for shelter, and low-disturbance shorelines that let wildlife rest and feed.

Across its range, the species faces a familiar suite of pressures that erode these conditions. River regulation through dams and channelization changes flow patterns and can flood or desiccate key nesting and foraging sites. Dredging and sand mining strip riverbeds of structure. Clearing of riverside forests removes cover and potential nest cavities. Add to this the impacts of pollution and heavy boat traffic, and the quiet refuges these birds need grow scarce. Climate shifts, which alter rainfall and temperature regimes, further complicate the delicate balance of breeding and feeding cycles.

Conservation benefits that flow to people

Protecting a river specialist like the scaly-sided merganser yields benefits well beyond birdwatching. Healthy riparian corridors stabilize banks, reduce flood risks, filter water, and sustain fisheries. They also keep agricultural soils productive by reducing erosion and maintaining pollinator and predator communities that naturally regulate pests. Many wild species have inspired medical innovations and continue to inform new therapies and biomimicry solutions. Meanwhile, responsible nature tourism — guided experiences, local homestays, and community-run visitor services — can create steady income for residents while encouraging stewardship of the ecosystem that supports those livelihoods.

What helps next

Moments like this often spark practical steps that make rivers better for wildlife and people alike. Useful measures include:

• Safeguarding key stretches of river with seasonal quiet zones, especially during migration and breeding periods.
• Maintaining or restoring native riverside vegetation to provide shade, nesting options, and stable banks.
• Designing and operating water infrastructure to preserve natural flows and sediment movement where possible.
• Strengthening oversight of dredging and sand extraction to protect habitat complexity.
• Reducing pollutants at the source and improving wastewater treatment in surrounding communities.
• Supporting community science surveys to track rare visitors and guide adaptive management.

How to watch without disturbing

When a high-profile species drops in, it’s tempting to get as close as possible. But distance is a birder’s best tool for protection. Observers are encouraged to:

• Use binoculars or telephoto lenses and stay well back from the water’s edge.
• Avoid drones, flash photography, and playback of calls, which can stress birds.
• Stick to established paths and respect any posted access limits.
• Keep groups small and quiet, and minimize time spent near sensitive areas.

The scaly-sided merganser’s cameo at Huguangyan is more than a checklist triumph; it’s a reminder that when rivers are given room to breathe, life responds. If we protect the quiet, clean corridors these birds require, we protect the same natural systems that keep our communities resilient. With thoughtful stewardship, today’s fleeting sighting can become tomorrow’s regular visitor — and a living testament to what healthy waters can sustain.