Jamaica Released Thousands of Rat Killers - Then Nightmare Happened | Farming Documentary

Added: 2026-05-12

[00:00:02]No one could have imagined that a small animal introduced to the island could cause the extinction of a bird species, silence the forests, and leave behind a rabies threat that lasted for over 100 years.

[00:00:14]They thought that decision would save the economy, but no one expected it to create an irreversible disaster.

[00:00:22]Comment Hassoun if you're curious about the terrifying story hidden behind it.

[00:00:30]In 1872, a ship docked in Jamaica carrying what was then believed to be the savior of the entire colonial economy.

[00:00:38]There were only nine tiny animals on board, all from Calcutta, India, four males and five females.

[00:00:47]At that time, Jamaica was almost entirely dependent on agricultural plantations for its survival.

[00:00:55]Everything hinges on sugarcane.

[00:00:59]The endless sugarcane fields provide livelihoods for the farmers and produce white gold [music] for the European market.

[00:01:08]But right beneath those sweet sugarcane stalks, another force is silently spreading.

[00:01:15]Those were swarms of black and brown rats that had arrived on the island on merchant ships.

[00:01:20]There is no winter to slow down the reproduction rate.

[00:01:25]No predator is powerful enough to control them.

[00:01:29]As a result, the population exploded out of control.

[00:01:38]Imagine this, roughly a quarter of Jamaica's sugar production disappears with 25% of an entire year's labor wasted in the shadows.

[00:01:48]The damage amounted to 100,000 pounds annually, equivalent to tens of millions of dollars today.

[00:01:55]The plantations were then on the verge of complete collapse.

[00:02:01]If the sugar industry collapses, the entire economy of the island could fall apart with it.

[00:02:10]The plantation owners tried almost every method.

[00:02:14]They brought carnivorous ants from Cuba, but these ants turned around and bit people and poultry.

[00:02:22]They continued releasing toads from Barbados, but the toads chose to eat eggs and beneficial insects instead.

[00:02:31]Traps were set everywhere.

[00:02:34]Poison was spread thickly across the fields, but rodents quickly learned to dodge.

[00:02:41]Each setback only makes the anxiety spread further.

[00:02:47]In that context, importing nine Indian mongooses was seen as a last-ditch audacious move.

[00:02:55]In May 1872, they were released at the Spring Garden Plantation.

[00:03:01]But what happened afterward was not just the story of one island, but also a costly lesson about humans interfering with nature without fully understanding the chain reaction that follows.

[00:03:13]If you want to know what really happened, watch until the end of the video.

[00:03:19]And don't forget to subscribe to the channel before we continue this story.

[00:03:28]In the first few weeks after being released at the Spring Garden Plantation in 1872, the mongooses almost disappeared from human sight.

[00:03:38]But there were no traces of them. Dead rats appeared in increasing numbers around the sugarcane fields. The gnawing sounds at night also became less frequent.

[00:03:52]In just about 6 months, the damage caused by rodents was reduced by almost half.

[00:03:58]That 50% figure was like a ray of hope for plantation owners on the verge of bankruptcy.

[00:04:06]And what made them absolutely confident was not only the incredibly rapid effectiveness, but also the predatory characteristics of this newly introduced animal.

[00:04:22]Mongooses are extremely agile, have excellent reflexes, and hunt with great precision.

[00:04:30]With rats still abundant in the fields, finding prey is almost effortless.

[00:04:36]The abundant food source has allowed the mongoose population to increase rapidly with virtually no obstacles to stop it.

[00:04:51]Just about 10 years later, around 1,882, they had spread throughout Jamaica.

[00:04:59]From coastal sugarcane fields to deep inland areas, the footprints of this small animal can be found almost everywhere.

[00:05:10]The sugar industry estimates it saves around 150,000 lb a year thanks to the significant decline in the rat population.

[00:05:18]In the eyes of many, this is not only an effective solution, but also a testament to the power of pragmatic thinking.

[00:05:27]The London press at the time consistently praised William Bancroft, a Scot and English sugarcane plantation owner living in Jamaica in the 19th century, as a symbol of pragmatic thinking that applied science to protect economic interests.

[00:05:45]He is famous for proposing and promoting the introduction of mongooses from India to Jamaica to control rats that destroy crops.

[00:05:58]The story in Jamaica quickly spread beyond the island's borders.

[00:06:03]Plantation owners in the Caribbean and throughout the Pacific region began to view this as a model to follow.

[00:06:12]If one island can solve the problem by introducing a predator, why can't other places do the same?

[00:06:19]In a short period of time, mongooses were exported to more than 30 islands from Puerto Rico, Cuba, and Grenada to Fiji [music] and many other places.

[00:06:31]By 1883, Hawaii had also imported this civet species believing they possessed a biological shield to protect their crops from rat damage.

[00:06:41]At the time, almost no one questioned the long-term consequences.

[00:06:47]The immediate success overshadowed any doubts. The reduced damage figures, the annual savings, and the rapid [music] spread of the new population were all seen as evidence that the initial decision was entirely correct.

[00:07:08]But no one thought that the rapid development of a predator species in a new environment could create unpredictable changes.

[00:07:16]Amidst the glow of positive results, confidence in biological control gradually reached its peak.

[00:07:25]And it was precisely at the moment when humans believed they had control over nature that the subtle changes beneath the surface began to emerge.

[00:07:35]The first signs that things were going off track didn't appear with a loud disaster.

[00:07:41]They arrived in silence.

[00:07:48]In 1879, just about 7 years after the first nine mongooses were released into Spring Garden, a species of seabird endemic to Jamaica disappeared forever.

[00:07:59]That's Petrel Jamaica.

[00:08:03]These birds typically nest in earthen burrows in the Blue Mountains, an area that was once virtually free of predators.

[00:08:11]In the air, they can fly very far out over the sea.

[00:08:16]But once they land on the ground, these birds are slow and almost defenseless against land predators.

[00:08:30]From echoing cries in the night, they gradually faded into memory. The last recorded sighting of this bird also occurred in that same year.

[00:08:45]Initially, very few people linked the disappearance to the mongoose.

[00:08:51]However, by 1888, even William Bancroft himself was forced to acknowledge a difficult reality.

[00:09:00]The animal that was once expected to maintain pressure on rats has now changed its hunting behavior.

[00:09:07]They are no longer focused on their original goal.

[00:09:15]The reason lies in a factor that was almost unstudied at the time, the circadian rhythms and activity patterns of species.

[00:09:23]Mice primarily forage at night.

[00:09:27]Meanwhile, mongooses hunt during the day.

[00:09:33]Black rats are exceptionally good climbers. They gradually move their nests higher up in the treetops.

[00:09:40]In contrast, mongooses are accustomed to hunting on the ground and have relatively limited climbing abilities.

[00:09:51]As the rat population decreased and the surviving individuals learned to avoid each other, the two species gradually became parallel lines that rarely intersected.

[00:10:05]In an environment like Jamaica where many reptiles, birds, and amphibians evolved with little exposure to agile predators from the mainland, the arrival of the mongoose was like an ecological shock.

[00:10:18]Modern analysis of stomach samples reveal that approximately 93% of the mongoose's diet is actually not mouse.

[00:10:28]Instead, they hunt lizards, frogs, crabs, young birds, and even eggs.

[00:10:36]Organisms that once played a vital role in the food chain are now becoming the primary source of nutrition for new predators.

[00:10:53]When an endemic species disappears, the ecosystem usually doesn't collapse immediately.

[00:11:03]The trees are still green.

[00:11:06]The forest is still there.

[00:11:09]But gradually, the sounds began to change. Bird calls became less frequent, and the number of amphibians also decreased sharply.

[00:11:23]Later, ecologists called this phenomenon the empty forest syndrome.

[00:11:28]The landscape remains intact on the surface, but the biological links within have gradually disappeared.

[00:11:39]Ironically, all of this happened while the plantation owners were still pleased that damage from rats had decreased significantly.

[00:11:48]On paper, it was an economic success.

[00:11:52]But beneath the surface, ecological imbalance is quietly accumulating.

[00:11:59]From a solution once lauded, mongooses have gradually become a major disruptive force.

[00:12:07]That change didn't happen overnight, but once it began, it quietly reshaped the future of the entire island.

[00:12:21]The reason lies in the species' incredible reproduction rate.

[00:12:26]Mongoose can become pregnant when they are as young as 4 months old.

[00:12:31]A female can give birth to two three litters per year, with each litter containing three four offspring.

[00:12:47]Currently, the Indian mongoose is found on 33 Caribbean islands and in many other places around the world.

[00:12:54]The International Union for Conservation of Nature, IUCN, lists them among the 100 most dangerous invasive species [music] globally.

[00:13:04]For large islands, complete eradication is almost impossible.

[00:13:10]A more realistic goal [music] is to minimize damage in sensitive areas.

[00:13:17]Modern measures focus on local control, deploying oral rabies vaccines, and erecting electric fences around protected areas.

[00:13:27]More than 100 years after the first nine individuals were released in Jamaica, the story is far from over.

[00:13:37]What started as a seemingly perfect economic solution has had far-reaching consequences affecting biodiversity, agriculture, and public health.

[00:13:50]The mistake wasn't in the initial intention, but in humanity's failure to fully appreciate the complex interconnectedness of nature.

[00:14:00]Every ecosystem is a network where all its components are closely interconnected.

[00:14:07]Even a small change can lead to lasting upheavals that can extend for generations.

[00:14:16]Nine tiny creatures were brought in with the hope of saving an entire economy, but this inadvertently triggered a chain of upheavals that lasted for more than a century.

[00:14:27]If you lived in 1872, would you have supported releasing mongooses to save crops?

[00:14:33]Please share your thoughts in the comments section.