In 2009, nine Iberian lynx were released into a shrubland valley in Spain’s Córdoba province. The animals had been bred in captivity, and roughly half of similar releases had ended in death within a year. With fewer than 100 lynx left in the wild, the margin for error was minimal. Spain had already invested more than 70 million euros in recovery efforts, and the population remained in the hundreds.
Four months later, field ecologist Francisco Palomares reviewed camera trap footage from the valley. Instead of the lynx he expected, he noticed something missing: foxes. Their detection rates had dropped sharply, and mongooses had become scarce as well. The nine lynx had not killed them in large numbers. The smaller predators had left on their own, sensing the presence of a top predator. In the weeks that followed, rabbit burrows began appearing in areas where none had been recorded before. No one had planned this sequence, but the valley was reorganizing itself around the lynx.
The Iberian lynx is smaller than a German shepherd and heavier than a domestic cat, with spotted fur and ear tufts adapted for low-light hunting. It feeds almost exclusively on European rabbits, which make up 85 to 95 percent of its diet. A breeding female needs one to three rabbits per day to raise her young. It does not switch prey when rabbits decline. When rabbits disappear, lynx numbers follow within a season or two.
The species had lived across the Iberian Peninsula for roughly 10,000 years, according to fossil records. In the 1940s, researchers counted about 15 distinct subpopulations in Spain and Portugal. Then, in 1953, Spain’s Ministry of Agriculture issued the “Alimañas” law, a pest control decree under Francisco Franco’s government. The law listed species the state wanted removed from the countryside: wolves, foxes, eagles, kites, vultures, and the Iberian lynx. A bounty was paid for each animal presented. A wolf was worth 15 pesetas, a pregnant wolf 20. The lynx was priced at 3.75 pesetas, about a quarter of a wolf’s value and less than a day’s wages.
The campaign eliminated roughly 2,000 wolves, 55,000 foxes, 5,000 eagles, 6,000 hawks, and 1,000 vultures. Lynx deaths were not recorded separately, because killing them was not considered worth tallying. Bounty systems were common across Europe at the time, but Spain’s version was unusually destructive because it targeted a species with no population buffer.
Spain granted the lynx legal protection in 1973, and Portugal followed in 1974. By then, the 15 subpopulations had collapsed to two. By 2002, those two held only 94 animals, with about 25 breeding females. Twenty-nine years of protection had slowed the decline but had not reversed it.
In 2019, a hunter in Castilla-La Mancha shot and killed a collared female lynx named Novar, which had been individually monitored for years. He said he mistook her for a fox. The court ordered him to pay 100,800 euros in compensation and suspended his hunting license for three years. The same state that had once paid 3.75 pesetas for a dead lynx was now demanding six figures for one killed by mistake.
The bounty law was only part of the story. In 1952, myxomatosis reached Spain. The virus had been deliberately introduced elsewhere in Europe to control rabbit populations on farmland. Within three years, it killed more than 95 percent of European rabbits across the peninsula. The pest control law came a year later. No one coordinated the two, which is exactly why they worked so well together.
In the late 1980s, rabbit hemorrhagic disease arrived, striking populations that had begun recovering from myxomatosis. In the 2000s, a new strain, RHDV2, killed young rabbits, including those vaccinated against the earlier strain. Mortality rates in affected populations ranged from 70 to 90 percent. In Doñana National Park, rabbit numbers fell more than 80 percent between 2012 and 2013. In Andújar Natural Park, the decline was about 75 percent between 2010 and 2013. Both areas were key lynx habitats.
Studies tracking the two species found that a 60 to 70 percent collapse in rabbit numbers was matched by roughly a 65 percent drop in lynx breeding success. The rabbits also functioned as ecosystem engineers, their burrows aerating the soil and their grazing maintaining the mix of dense scrub and open ground that dozens of vertebrate species depend on. Remove the rabbit, and the landscape structure itself begins to change.
By the 1990s, Spain understood most of this and began funding recovery programs. European Union LIFE funds started flowing in the mid-1990s. A breeding center was established at El Acebuche in Doñana, and protocols were developed for a difficult species, one whose siblings sometimes fight to the death in their first weeks. By 2009, the program was producing reliable numbers of captive-born kittens.
The problem was survival after release. Captive-born lynx died at a rate of roughly 52 percent after release. Wild-born lynx moved between sites died at about 29 percent. The gap was not about prey availability, since release sites were chosen partly for rabbit density. It was physiological and behavioral. The captive animals had grown up on controlled feeding schedules in enclosures with predictable pressures. Their metabolisms were shaped for that world. They knew how to kill rabbits but not how to live in the wild.
Disease also struck the wild population. In 2007, feline leukemia virus swept through the Doñana group, then the largest wild Iberian lynx population in the world. The virus killed roughly two-thirds of the animals it infected. Between 2006 and 2011, disease accounted for about 38 percent of all recorded lynx deaths.
Rabbit management efforts ran in parallel. Artificial burrows were built, shrubs were replanted, rabbits were vaccinated and relocated. Results were local, inconsistent, and fragile. One burrow complex thrived for two seasons, then emptied after a disease outbreak. One relocation failed due to unsuitable vegetation.
By the time the LIFE Iberlince and Lynx Connect projects reached full scale, Spain and the EU had allocated more than 70 million euros. The lynx remained critically endangered. The failure was not lack of effort or funding. It was structural, and it was not visible from inside a breeding center or a budget line.
By the mid-2000s, wild Iberian lynx existed in only two places: Doñana in the southwest and Sierra Morena in the south-central mountains. Both were isolated from each other and from any other suitable habitat by highways, farmland, reservoirs, and, most importantly, insufficient rabbit density in the spaces between them. Two groups without genetic exchange do not constitute a viable species.
The decision was made to expand rather than reinforce: establish new populations in areas that had not seen lynx for generations. Sites were evaluated on four criteria: rabbit density, habitat suitability, landowner cooperation, and distance from high-traffic roads. Two sites passed first: Guadalmellato in Córdoba and Guarrizas in Jaén, both within the broader Sierra Morena range.
In 2009, captive-bred animals were placed in transport boxes and driven to the release points. Each lynx has a unique coat pattern, which allowed researchers to identify individuals by camera without recapturing them. GPS collars tracked movement, and camera traps were placed roughly every 500 meters across the release area. At dawn, the box doors were opened. For a second or two, nothing happened, since animals raised entirely in enclosures do not necessarily register that the wall is gone. Then they moved, low and fast, disappearing into the scrub within seconds. The researchers did not follow. From that moment, the experiment ran on its own terms.
The nine animals behaved as expected. Males wandered widely and irregularly, testing boundaries. Females settled faster, establishing home ranges within two to three weeks. Then the camera data began showing something the teams were not looking for. Red fox detections dropped sharply, not gradually, in the same grid cells where lynx had established territories. Egyptian mongoose detections fell in the same areas over the same period. The foxes and mongooses had detected the presence of a top predator through scent and disturbance patterns and had left before the lynx could have killed them in meaningful numbers.
This is a phenomenon ecologists call mesopredator release. When a top predator is removed, mid-sized predators expand to fill its ecological space. In Mediterranean scrubland, the dominant mesopredators are red foxes and Egyptian mongooses. Both eat rabbits, but differently from lynx. Lynx hunt adults at low density through cover. Foxes dig. Mongooses enter burrows and hunt young, exerting continuous pressure that pushes colonies to abandon sites rather than breed. In the absence of a top predator, this middle layer removes far more rabbit biomass than a few lynx would.
Research published by Palomares and colleagues in Biological Conservation quantified what the camera traps showed across multiple release sites. In areas settled by lynx, red fox and mongoose abundance dropped by up to tenfold compared to lynx-free areas. The mechanism was largely behavioral rather than lethal. Lynx kill foxes and mongooses opportunistically, but the dominant effect was avoidance. The smaller predators recognized that an animal capable of killing them controlled the area, so they left or became cautious enough to hunt less efficiently.
The researchers noted caveats. Camera detection rates measure activity, not absolute abundance. A fox that becomes more cautious is harder to photograph even if it does not leave. Habitat improvement work was also underway at some sites during the same years. But the trend held across sites and years. The lynx was protecting rabbits not by leaving them alone but by making the environment more dangerous for the animals that preyed on them at a faster rate.
The population numbers reflect this. There were 94 lynx in 2002 and roughly 319 by 2013. A specialist rabbit hunter cannot triple its numbers without the rabbit population growing underneath it. Fox decline, mongoose decline, rabbit rise, lynx rise, in that order, without a management plan directing it.
Spain had spent decades treating rabbits and lynx as two separate engineering problems. The correct intervention was structurally simpler and far less expensive: restore the top predator and let the hierarchy regulate itself.
Two threats in this environment do not respond to predators. The first is road traffic. In 2024, 214 Iberian lynx deaths were recorded across Spain and Portugal. About 75 percent, 162 animals, were vehicle collisions. In 2025, road deaths reached 212, roughly eight out of every ten recorded deaths. These are the arithmetic of success. Expanding populations move into new territory, and new territory means roads. A lynx’s home range can extend to 30 square kilometers, and dispersing juveniles travel much farther, across infrastructure built without consideration for a cat no one expected to survive. Underpasses, fencing, and crossing structures are being installed and work where they exist. The problem is speed: the population is growing faster than the engineering can keep up.
The second threat is the rabbit virus. RHDV2 has not disappeared. The 2013 outbreaks in Doñana and Andújar showed what it can do. Castilla-La Mancha now holds nearly 46 percent of Spain’s lynx population, and rabbit numbers there remain vulnerable to the same virus. A single outbreak in the wrong region at the wrong point in the breeding cycle could cut short a recovery that took 30 years to build. A top predator can suppress foxes, but it has no answer for a virus in a burrow.
Human factors also persist. Hunters on some estates in Extremadura and Andalusia were initially hostile to reintroductions, arguing that lynx would compete with paying shooters for game. Field data largely contradicted this. Lynx hunt scrub-dwelling rabbits rather than the open-ground species around which hunting estates are organized, and some estates with lynx reported better rabbit numbers for the reasons shown by the camera traps. Where enforcement is weak, illegal killing and poisoning continue. Where it is strong, Andalusia has reduced recorded wildlife poisoning incidents by more than 90 percent over two decades.
Funding remains cyclical. The Life Lynx Connect program runs on EU grants awarded in rounds. Favorable status requires about 750 breeding females. In 2024 there were 470. By 2025, the number had reached 542, still below target but the best figure ever recorded.
In June 2024, the numbers had shifted enough for an official judgment. The International Union for Conservation of Nature removed the Iberian lynx from the endangered category and reclassified it as vulnerable. It is the first cat species in recorded history to be downgraded from endangered as a direct result of conservation intervention. The change in status is narrow: a species moved from a very high risk of extinction in the wild to a high risk. That is the full distance covered, achieved over about 20 years and more than 70 million euros.
The population figures behind the new classification: 94 in 2002, roughly 319 by 2013, and 2,663 by 2025, distributed across a growing number of subpopulations rather than concentrated in two fragile areas. Nearly 28 times the 2002 population, for a species the state had once valued at 3.75 pesetas.
The specific thing the nine lynx demonstrated in the Guadalmellato valley is the part that can be generalized. Spain spent 50 years managing two problems, lynx and rabbits, as though they were separate. Both were necessary, and neither alone was sufficient, because both treated symptoms in a food web whose structure had been broken at the top. The missing piece was not an external addition. It was a relationship. The lynx was not just an animal needing rescue; it was the organism that had kept the middle layer of that ecosystem in balance for 10,000 years. Its absence had allowed foxes and mongooses to expand into a rabbit population that could no longer support anything above them. Restore the cat, and the pressure it exerts simply by existing does work no burrow-building budget can match.
The most important number in this story is not 2,663. It is nine. Nine captive-born animals released at dawn into a valley that had forgotten they existed, rearranging it within a single season.
The Iberian lynx has not yet been declared safe. Eight out of ten recorded deaths last year were road collisions. The rabbit remains one virus away from another collapse, and breeding females number about 200 short of a favorable status. But for the first time since the ministry printed a price list in 1953, the species is not declining. It is increasing. Seventy-three years after the state decided a lynx was worth less than a day’s wages, the animal it priced at zero turned out to be the one thing the landscape cannot function without.
