The idea of fish preying on birds might seem unusual, as most people imagine aquatic life staying strictly beneath the surface. However, certain fish species have been observed capturing birds, demonstrating a surprising and rare predatory interaction within aquatic environments. This behavior challenges common perceptions of food webs and highlights the diverse and unexpected adaptations found in the natural world.
Fish Species Known to Catch Birds
The giant trevally, Caranx ignobilis, stands out as a well-documented example of a fish known to prey on birds. These large, powerful fish are found in the tropical waters of the Indo-Pacific region and can grow to be over a meter long, with some individuals weighing up to 40 kilograms. They are apex predators in their marine habitats, feeding on other fish and crustaceans. Footage from the Seychelles captured in 2017 showcased giant trevally launching themselves from the water to snatch fledgling terns.
Other fish species have also been noted for this behavior. The wels catfish, native to Eurasia, eats a variety of prey, including birds like pigeons. These large freshwater fish can reach lengths of around 3 meters. In Africa, the Goliath tigerfish, a formidable freshwater predator, has been observed attacking low-flying barn swallows. Monkfish, found in the Atlantic Ocean, have also had birds like dovekies found in their stomachs.
Hunting Techniques Employed
Fish that prey on birds employ specific ambush techniques that exploit the birds’ vulnerability at the water’s surface. The most dramatic method involves explosive leaps from the water. Giant trevally, for instance, track birds from below the surface before projecting themselves up to a meter out of the water to engulf their prey. They are capable of expanding their mouths to a considerable size, allowing them to completely encompass a bird.
This ambush strategy targets young or inexperienced birds, such as fledglings, which may be less adept at taking off or landing on the water, making them easier targets. In some cases, fish will wait for birds to skim the water’s surface or come close to the edge. For example, smaller wels catfish have been seen ambushing pigeons from the water’s edge, even beaching themselves briefly to secure their prey. This demonstrates a calculated approach to catching prey outside their typical aquatic environment.
Understanding This Rare Behavior
The predation of birds by fish is an opportunistic behavior, rather than a primary or consistent food source. It occurs under specific environmental conditions, such as during bird nesting seasons when young, inexperienced birds are abundant and more vulnerable near the water. Fish like the Goliath tigerfish resort to bird predation when their usual food sources are scarce, indicating it can be a response to hunger or limited prey availability.
These events are not a regular part of the diet for most of these fish species. The energy expenditure involved in leaping from the water or pursuing avian prey suggests that the benefit of obtaining a meal must outweigh the effort and risk. This behavior highlights the adaptability of predators, allowing them to exploit available resources in their environment when conditions align, even if it means stepping outside their typical predatory patterns.