Javali: Why This Has Become a Priority at Raízes da Montanha

The scale and frequency of Javali damage affects almost every part of what we are trying to achieve — and a new Government proposal raises questions that must be answered before any scheme begins.

Javali—wild boar—remain at the centre of my attention because of the scale and frequency of the damage being caused at Raízes da Montanha.

Some readers may wonder why we are devoting so much time to this one issue. The answer is simple: Javali damage affects almost every part of what we are trying to achieve.

Across our 7.5-hectare property on the slopes of Fóia, repeated rooting has removed established ground cover, exposed bare soil, disturbed restored terraces and damaged areas intended for cultivation. On steep ground, bare and loosened soil is particularly vulnerable when the autumn rains arrive.

This creates additional work and expense, but the consequences go much further. It affects soil restoration, water retention, planting, erosion control, fire resilience and ultimately whether previously abandoned land can be brought back into productive management.

Scientific studies confirm that wild-boar rooting can overturn substantial areas of soil, remove vegetation cover and alter soil structure and nutrient distribution. However, the ecological effects vary according to habitat, slope, season and the intensity of disturbance. Occasional rooting can form part of a natural ecosystem; repeated, extensive rooting on vulnerable agricultural terraces is an entirely different matter. This is why management must be based on measured impacts rather than assumptions.

The proposed payment for animals killed

Social media and the Portuguese press have been full of reports this week about a Government proposal to pay hunters for every Javali killed in areas considered to have excessive populations.

It is important to be precise. The Ministry of Agriculture and the Sea has confirmed that it is developing a pilot project, but the payment, geographical areas, eligibility rules and verification arrangements have not yet been published.

Reports about refrigerated storage concern a related initiative being discussed by the Câmara Municipal de Mação. The municipality is considering support for hunting activities, a refrigerated facility and arrangements for handling the animals killed. This has not yet been confirmed as a general feature of the national pilot project.

The pilot project should not be dismissed before its full details are known. Financial assistance may help overcome the costs of organised control. Nevertheless, payment for each carcass creates important questions that must be answered before the scheme begins.

How will officials verify where and when each animal was killed? How will duplicate claims, animals brought in from outside the target area or animals retained to support future payments be prevented? Will carcasses be individually identified and recorded by sex, age, weight and location? Most importantly, will success be assessed by the number of animals presented, or by an independently measured reduction in population and damage?

Lessons from bounty schemes elsewhere

There is scientific evidence supporting these concerns.

A bounty programme at Fort Benning in Georgia, USA, resulted in 1,138 wild pigs being killed at a total cost of US$57,296. Despite that, surveys indicated that pig density and occupancy increased during the programme. Sounder size and the number of juveniles per adult female also increased.

The researchers suggested two possible causes: bait used by participants provided additional food, while hunters tended to target animals offering the best return for their effort or the greatest trophy value rather than those having the greatest effect on population growth. The study does not prove that every bounty scheme must fail, but it demonstrates that a large kill total is not, by itself, evidence of successful population control.

American wildlife authorities also warn that bounty schemes can encourage false claims, the movement of animals or carcasses across administrative boundaries, and incentives to retain a continuing population. I have not found reliable evidence proving that hunters in the Fort Benning study were actually breeding pigs for the bounty, so I would not make that specific allegation. However, the wider risk of fraud or 'bounty farming' is recognised and should be designed out of any Portuguese scheme.

How many animals must be removed?

Figures between 60% and 75% are frequently quoted, but these need careful explanation.

Several population models have suggested that rapidly reproducing wild-pig populations may require the sustained removal of approximately 66–70% of the total population every year merely to prevent further growth. This does not mean that exactly 60–75% of every individual sounder must be removed, nor is it a universal target that can automatically be applied to Monchique.

The required rate will depend upon local population density, reproduction, food availability, immigration from surrounding areas and the effectiveness of the control methods being used. More recent scientific analysis has warned against treating 70% as a fixed rule.

This highlights the most fundamental question for Portugal: how can an effective removal target be established unless there is a credible estimate of the population before the intervention begins?

The Government says pilot areas will be selected using technical criteria and the University of Aveiro's research. That is encouraging, but the baseline figures, targets and measurements of success must be made publicly understandable.

Targeting the right animals

Removing a small number of adult males will generally have little effect on population growth because Javali are polygynous: one remaining male can mate with several females. Removing females and juveniles has a much greater effect on future population growth.

My earlier suggestion that removing large males directly increases litter size by leaving more food for pregnant females was too definite. Food availability and female body condition can influence reproduction, but the absence of adult males has not itself been shown to cause larger litters.

The stronger, evidence-based point is that a scheme which encourages participants to select large males, while leaving breeding females and their young, may produce impressive-looking kill figures without delivering meaningful population reduction.

Whole-sounder trapping

One of the most promising methods is whole-sounder removal.

Large corral traps can be left open while the animals become accustomed to entering them. Cameras allow the trap to be monitored and the gate to be closed remotely once the complete family group is inside. Removing the entire sounder avoids leaving most of the breeding group behind and reduces the likelihood of creating trap-wary survivors.

A 2023 controlled study found whole-sounder removal more effective at reducing wild-pig density than traditional control based mainly on conventional traps, dogs and opportunistic shooting. However, researchers also noted the greater time and expense involved and the problem of animals recolonising from neighbouring areas.

Whole-sounder trapping is therefore a highly effective tool, but it is not the only possible method. Successful management is likely to require an integrated programme combining monitoring, professionally coordinated trapping, properly targeted and lawful shooting, removal of attractants, protection of particularly vulnerable areas and cooperation across neighbouring properties.

No single landowner can solve a landscape-scale problem alone.

The food chain and lead ammunition

Refrigerated storage does not, on its own, make a carcass suitable for human consumption.

DGAV states that wild game intended for commercial sale must pass through an approved wild-game handling establishment, undergo post-mortem inspection by an official veterinarian and, in the case of every Javali, be tested for Trichinella.

There is also the separate question of ammunition. Scientific research shows that lead rifle bullets can fragment on impact, leaving pieces—sometimes extremely small—within the meat. Radiography can identify many metallic fragments, but it may not detect the smallest particles. Routine X-ray examination is not listed in the published DGAV requirements I have found.

Before a large-scale route into the food chain is created, the authorities should explain how ammunition type will be recorded, whether non-lead ammunition will be encouraged or required, how damaged tissue around the wound channel will be removed, and how each carcass will remain traceable from the place of shooting to the final product.

Cooperation and measurable results

Portugal already has an official Strategic and Action Plan for Javali. Its objectives include understanding population size, assessing the animals' physical condition and examining the habitat factors affecting damage. The current University of Aveiro IMPACTO project is also evaluating control methods and updating knowledge of the Portuguese population.

What remains unclear from the perspective of a land manager is how national research, ICNF, municipalities, hunting-zone managers, hunting associations and the people recording damage on the ground are being brought together.

That is not a criticism of hunters. Hunters will undoubtedly be essential partners. Nor are we calling for the eradication of Javali. We are calling for balance and for a system in which every intervention is connected to measurable outcomes.

Success should not be defined simply by how many animals are killed. It should mean:

• —a verified reduction in population density;
• —less rooting and less bare soil;
• —fewer damaged crops, terraces and walls;
• —fewer road accidents;
• —reduced expenditure on defensive fencing and repairs;
• —improved disease surveillance and farm biosecurity; and
• —greater confidence among people considering restoring abandoned land.

This is why Javali management has become a key priority at Raízes da Montanha. Without effective and coordinated control, we risk repeatedly restoring ground only to see it disturbed again.

We will continue documenting the damage with photographs, dates, locations and repair costs. We will also continue asking constructive questions and sharing what we learn.

We are not against Javali, and we are not against hunting.

We are for balance—and for land management policies that can demonstrate that they are actually working.