Perched high above Little Guilin in Bukit Batok, a grey-headed fish eagle, one of Singapore's largest and most endangered birds, gets ready to pounce.
A carp struggles on the water's surface.
Photographers lie in wait - they have stuffed the poor fish with styrofoam so it is unable to sink.
The eagle dives, emerging with the fish in its talons. It devours the easy catch and, in the process, encounters a substance that tastes and feels unfamiliar.
The eagle does what it can to regurgitate the styrofoam, but many of these tiny particles of indigestible and potentially toxic material travel down its throat and remain in its gut, and could stay there for years.
About the writer
Mr David Tan, 26, is a researcher at the National University of Singapore's biological sciences department who studies urban ecology and evolution of birds.
As part of his work, he collects bird carcasses, which provide valuable genetic information that enables researchers to study bird evolution and conservation, among other things. He is also an avid birdwatcher and an amateur nature photographer.
In August this year, a group of photographers was filmed trying to obtain action shots of the eagle using this ploy. The evidence of their unethical practices was posted online and went viral, sparking outrage among nature photographers all over the world.
The incident, while exceptionally cruel, is hardly an isolated one.
Singapore is a biodiversity haven, home to more than 380 species of birds and 58 species of mammals. And with nature photography growing both in popularity and affordability since the 2000s, so too has the pressure to obtain spectacular shots of wildlife, leading to a steady rise in questionable and unethical practices.
The use of bait - an increasingly common practice in Singapore - appears at first to be not so clear-cut.
To its advocates, it is a harmless, even compassionate, pursuit. Feeding wild animals is good, they say, because it provides the animal with nourishment and helps it survive in an otherwise hostile environment.
So what does the science have to say about baiting and feeding?
Studies on rapidly declining farmland birds in Britain have shown that providing seeds during the barren winter months helps these birds to survive and maintain healthy population sizes during periods of food scarcity.
But such practices cannot apply to the humid tropics of South-east Asia, where food is plentiful all year round.
More importantly, most of the studies that show the benefits of feeding involve carefully managed conservation projects, such as those at zoos and aviaries, where both the types and amount of food provided are tightly controlled and feeding is carried out with clear conservation goals in mind.
No such monitoring or management occurs within local nature photography circles.
By far the most well-documented impact of baiting in the scientific literature is the habituation of animals towards human contact and human food.
As residents living in the vicinity of Bukit Timah and its long-tailed macaques are well aware, the less afraid wild animals are of humans, the greater the chance of experiencing some form of human-wildlife conflict as the animals become bolder and more aggressive.
The ultimate loser is the animal, since such conflicts are often followed by calls for culling to take place or result in the habituated animal being poached from the wild.
Another worry is the scientific evidence showing that opportunistic baiting of wild animals may cause malnutrition and even death.
Photographers generally rely on whatever bait is easiest to procure, which is often at odds with what an animal needs.
Last month, New Zealand news website The Dominion Post reported that an endangered kaka chick recently had to be put down after members of the public fed the chick's parents nuts, which the parents subsequently fed to their chick. The chick developed a severely deformed beak due to its bone development stopping prematurely.
In Singapore, the widespread use of store-bought insects to bait wild birds is also likely to cause harm.
Mealworms and crickets, by virtue of their relatively high fat content and low calcium to phosphorous ratio, are basically junk food for birds - full of empty calories and low on nutritional value.
And while some birds can survive on a pure mealworm diet for a day, data from animal husbandry studies around the world indicates that any more than that is likely to result in the creature developing serious obesity issues and liver problems.
This was the case earlier in March this year, when photographers were observed actively baiting the migratory hooded pitta with mealworms at the Singapore Botanic Gardens.
Over eight hours in a single day, the pitta consumed 27 mealworms and nothing else. This baiting went on constantly for at least three weeks, during which time the bird should have been foraging for a more diverse and nutritious array of food found naturally in the wild.
Indiscriminate baiting can also have negative consequences on the ecosystem.
Frogs have recently become a popular bait item among photographers, and many of these species, easily purchased from aquarium shops, are both potentially invasive and carriers of disease.
A 2012 study that included scientists from Singapore found that frogs from Singapore's aquarium trade were carriers of Batrachochytrium dendrobatidis, a fungus lethal to many frog species, and one that is currently decimating native frog populations in Madagascar and South America.
Among the carrier species were the crab-eating frog and the American bullfrog, both of which were recently used to bait the black- backed kingfisher in Venus Drive and the ruddy kingfisher in Bidadari respectively.
Although we have yet to experience a major outbreak of Batrachochytrium dendrobatidis in Singapore, the continued use of carriers from the aquarium trade as bait increases the risk of this happening.
In some cases, the object of the lens may potentially be invasive itself. In February, photographers were spotted using seeds to bait the cut-throat finch, an African species likely introduced as a result of escapees from the pet trade, at Pasir Ris Park.
While most newly introduced species often fail to form stable populations and disappear quickly as a result, supplementary feeding may help them establish a stable breeding population. This could eventually lead to native birds being out-competed and ecosystems being destabilised.
The common thread underlying all these consequences is their intangibility. Unlike practices that cause immediate death and destruction, many of the negative consequences of baiting are incremental. Like the pieces of styrofoam in the grey-headed fish eagle's gut - they often accumulate without any noticeable impact until it is too late.
On the issue of baiting, the science is clear.
Baiting as it is currently practised has no place in nature photography. Ultimately, a good shot still depends on good old-fashioned patience, being observant and being unbelievably lucky.