A butterfly that travels from Canada to Mexico to hibernate and reproduce, a whale that holds its species' record with 22,500 kilometers of travel across the oceans, or the arctic tern, a bird that -attention, spoiler- holds the longest migration in the animal kingdom. Now that spring is beginning and with it many species are on the move, we explain the main migratory routes of planetary fauna. The highways of wildlife.

Around 350 tractors blocked the C-25 highway (the Eix Transversal) on Monday morning to protest the overpopulation of wildlife in Catalonia, in a demonstration organized by the main agricultural organizations in the region. The mobilization, which began at 9 a.m., brought farmers to the streets to demand, above all, "control of overpopulations of game animals"—especially wild boar, rabbits, roe deer, and red deer—and a "review" of the Livestock Health Service. The march was supported by Unió de Pagesos, Revolta Pagesa, Asaja, and the Plataforma Pagesos o Conejos (Farmers or Rabbits Platform).

It is estimated that there are around 200,000 wild boars in Catalonia, distributed unevenly across the territory. A monitoring program has been in place for two decades, documenting the differences in population density: there are more than fifteen animals per square kilometer in Alt Empordà and Les Gavarres, fewer than three in Els Ports de Tortosa-Beseit, and between three and six along the coast. Collserola ParkThe area is where the outbreak of African swine fever, which has raised all the alarms, is concentrated. Generous rainfall, an abundance of holm oaks, oaks, and beech forests, along with extensive irrigated crops, favor the proliferation of these animals, which generally follow an upward demographic trend. In fact, the Catalan government's program indicates that "wild boar populations do not appear to be close to reaching their peak and have the potential to continue growing."

A century later, a wolf has been born again in Catalonia. This "historic milestone" was announced Wednesday by the Catalan Interior Ministry through its Rural Agents Corps. Three pups have been confirmed in a large area between Alta Garrotxa and Alt Empordà. The discovery comes after decades of monitoring the species, which had disappeared from the region. until a quarter of a century agoThen, the return of an isolated wolf was detected in the Cadí-Moixeró Natural Park. With the birth of the pups, as stipulated by regulations, the wolf automatically transitioned from an extinct species to an endangered species. The pairing of the parents of these three pups has not been an easy process. Almost two years ago, Rural Agents confirmed the presence of a wolf in this area of the Girona region. In May, they were able to genetically identify it and discovered it was a female. That same month, they located a second animal in the area, which they identified as a male. But the two wolves always traveled separately and were always far from each other. This changed in December 2024: suddenly, the two animals were together. From that moment on, the Rural Agents intensified the monitoring and surveillance of the area, which is a very large and extensive region with complex terrain.

Giraffes are one of the most iconic animals of the savannah. Their long necks, tall, twisted legs, and the unique pattern of spots and colors in their fur leave no one indifferent. They can grow to over five and a half meters tall, making them the tallest animal in the world. To pump blood to their heads, their heart, which weighs 11 kilograms, generates a pressure three times that of a human heart. Their tongue is also prodigious: it can measure up to half a meter in length and allows them to surgically pluck tiny acacia leaves from among very sharp thorns.

It's just a few minutes past nine in the morning, and the center's soundtrack is constant howls, flapping wings, and chirping. It's the end of July, and a new heat wave is already in sight. "Today I have three necropsies and several urgent cases to attend to," Rafael Molina tells us as soon as we arrive, gesturing for us to join him. "Where would you like to start?"

The coypu on display from the Onyar River near Girona create a great deal of excitement among passersby crossing the city's bridges. They are in greater demand than the classic carp, which has also been cornered by the Ebro thornback, another much more abundant foreign species that can reach comparable sizes. The coypu have found in the lower reaches of the river that runs through Girona, with its calm waters, rich vegetation, and naturalized banks, a perfect ecosystem for reproducing and forming families. They can be seen on the riverbanks or swimming in the water, and they do not flee at the presence of humans.

Sergi stands atop a wooden tower from where he can see almost the entire Llobregat Delta. However, he never takes his eyes off the binoculars he wears around his neck, which he uses to inspect the area. He joined the Rural Agents less than three years ago, and one of his tasks is to monitor this area, declared a natural interest site near El Prat Airport.

"The Generalitat is a mess." This is how the president stated this Tuesday. representative of Unió de Pagesos in the Territorial Hunting Council of LleidaRamon Comes, to denounce that farmers are receiving little help to deal with attacks by rabbits, wild boars, and roe deer. Comes asserts that neither the Department of Agriculture nor the Department of the Interior are providing the tools they had promised to combat the devastation of fruit trees, vineyards, and cereal crops caused by the overpopulation of wildlife. "We don't want to exterminate, we want to balance. The imbalance between farmers and wildlife is increasingly significant," he added. If this doesn't happen, Comes warned, "there will be consequences on the streets" in the form of protests.

Female sisterhood versus male aggression. This survival strategy transcends the human race and is also adopted by females. bonobo, the primates closest to humans, along with chimpanzees, and who, like all other mammals, are smaller than their male counterparts. Based on this purely physical disadvantage, females apply the popular saying that unity is strength or ingenuity is more valuable than brawn to outperform their male counterparts, according to the Max Planck Institute for Animal Behavior (MPI-AB), published this Thursday in the journal Nature.

Adding the blue crab to rice, fish broths and other culinary recipes has helped combat the plague that threatens the ecosystems in the Ebro Delta. The years-long war against this crustacean fishermen have been waging may have found a new ally. Tests carried out by researchers at the Institut de Recerca i Tecnologia Agroaliamentàries (IRTA) have shown that octopuses are natural predators of the blue crab, which they are capable of eating in large quantities if necessary: "A single octopus can eat up to 33% of its weight in crab meat in a single day", explains project coordinator Patrícia Prado.

The noise of parrots is no longer strange or exotic-sounding in the most populated areas of Catalonia, although 40 years ago they were an anecdote in the midst of the usual sparrows or serins. The list of newly arrived birds in the last decades is quite long –there are 17– and exotic birds have had a lot to do with it because they make up to half of the novelties detected by the third Atlas of nesting birds in Catalonia, a project led by the Institut Català d'Ornitologia (ICO), which is the most comprehensive study ever made of the birds that inhabit Catalonia. In view of the overall numbers, things have not gone badly for birds: it is estimated that between 8 and 12 million pairs of birds breed each year and the 233 species that can be found in some corner of the country are a very broad representation (39%) of Europe's bird wildlife.

Throughout the strict lockdown that began a year ago, images of animals in urban environments or habitually frequented by people proliferated on social networks. "Nature recovers", was proclaimed in many of these posts. It is true that, coinciding with spring, there was an increase in the proliferation of weeds in parks and gardens, tree wells, road verges, and roundabouts. But did those images of groups of deer strolling with the philosophical air that all ruminants have in the squares and streets of cities around the world really indicate an explosion of wildlife caused by the decrease of human presence?