Scottish Animal Welfare Commission: letter to Cabinet Secretary regarding the Guga Hunt

From: Dr Huw Golledge, Chief Executive and Scientific Director, Humane Slaughter Association
To: Professor Cathy Dwyer, Chair of SAWC
Date sent: 2 April 2026

Dear Professor Dwyer,

Re: Welfare assessment of killing methods used in the Sula Sgeir gannet (guga) hunt

Thank you for inviting the Humane Slaughter Association to provide evidence-based advice on whether more humane methods of killing could be applied to the annual harvest of juvenile northern gannets (Morus bassanus) on Sula Sgeir ("the guga hunt"). 

The HSA is an independent charity dedicated to improving the welfare of animals farmed or captured for food. We provide expert technical and scientific advice related to the welfare of animals at slaughter and during related activities including preslaughter transport and handling.

We understand that the Commission wishes to consider the animal welfare impacts of the hunt as it currently operates, and whether any harms could be reduced by adoption of different methods of killing the captured birds.

The current method

Juvenile gannets are currently captured from cliff-side nest sites using a long pole and then killed by one or more blows to the head. Reports indicate that birds frequently require multiple strikes before death occurs. It is difficult to verify how many birds are genuinely mis-stunned, and therefore exposed to additional suffering. However, in our experience effective stunning using manual blunt-force trauma is never 100% reliable and effectiveness relies on operator training, effective restraint of the target animal and the conduction of the procedure in appropriate conditions conducive to careful handling of the animal. It therefore seems highly unlikely that all the birds caught as part of the guga hunt will be instantaneously rendered unconscious by the first blow. Those that are not immediately stunned would be likely to experience severe suffering.

The current method raises serious welfare concerns at every stage, not just stunning/killing: capture, restraint, and handling, would all cause significant distress. It is difficult to reconcile the current procedure with NatureScot’s own licence condition that birds should be killed humanely, especially if one considers every action from the point of capture to be part of the killing process.

Assessment of alternative killing methods

We have considered three alternative approaches that could, in principle, improve welfare outcomes relative to the current practice.

1. Non-penetrative captive-bolt stunning

The HSA has extensive experience with non-penetrative captive-bolt devices for stunning poultry and other bird species. Typically, these devices are powered by explosive cartridges, but compressed gas-powered devices are also available. Devices such as the Accles and Shelvoke Cash Poultry Killer deliver a controlled percussive blow to the skull via a mushroom-headed bolt, causing immediate unconsciousness through concussion and brain trauma. In smaller birds this single blow is typically sufficient to cause death, though a confirmatory killing method (neck cutting or cervical dislocation) should always follow.

For birds the size of juvenile gannets, a convex bolt head would be required, and correct positioning on the skull is essential for an effective stun. The device must be well maintained, correctly loaded with the appropriate cartridge for the target animal, and applied by a trained operator to an appropriately restrained animal.

In a controlled environment, captive-bolt stunning would represent a significant improvement over the current method, as it delivers a standardised, mechanised blow of consistent force. However, several factors substantially limit its practical application on Sula Sgeir:

• Restraint requirement. The bird must be held firmly, and the head stabilised for accurate bolt placement. In the absence of purpose-built restraint equipment such as cones or shackles,⁵ this would in practice require one person to restrain the bird while a second applies the device. On exposed, uneven cliff terrain, reliable restraint and accurate device positioning would be extremely difficult to achieve consistently.
• Risk of mis-stunning. Even in controlled on-farm settings, correct positioning is critical and mis-stunning is a recognised welfare risk. The HSA’s guidance emphasises that if there is any doubt about the efficacy of a shot, an alternative method must be applied immediately. On the terrain of Sula Sgeir, the risk of inaccurate application would be considerably elevated.
• Equipment and logistics. Cartridge-powered captive-bolt devices must be properly maintained and can fail even with proper maintenance; back-up devices must always be available. The remote and austere conditions on Sula Sgeir would make proper equipment maintenance challenging.
• Restraint stress is not mitigated. The bird would still need to be captured by noose, handled, and physically restrained for the device to be applied. The welfare costs of this process (discussed below) would remain unchanged. In fact, it is possible that handling stress would be exacerbated since the period of restraint would likely be longer than for the current method.

2. Cervical dislocation

Cervical dislocation involves stretching the neck to sever the spinal cord from the brainstem, causing immediate loss of consciousness. It is widely used for on-farm killing of poultry, and can be performed manually or with the aid of a mechanical device. However, several factors substantially limit its practical application on Sula Sgeir:

• Weight limits. Whilst they do not apply to the guga hunt, the Welfare of Animals at the Time of Killing (Scotland) Regulations 2012 (SSI 2012/321), which implement EC Regulation 1099/2009,8 specify that manual cervical dislocation is permitted only for birds up to 3 kg liveweight, with a limit of 70 birds per person per day. Mechanical cervical dislocation devices such as the Livetec NEX® (a device developed from research funded by the HSA) extend the weight limit to 5 kg liveweight. Gannet chicks grow rapidly and reach peak body mass at approximately 8 to 10 weeks of age, at which point they can substantially exceed adult weight. Nelson (1966) recorded fledging weights of 3.1 to 4.1 kg, and chicks at peak weight (before the pre-fledging weight loss) may exceed 4 kg. The guga hunt takes birds at approximately 10 weeks old, when we presume they would be at or near peak weight. This places them at or above the 3 kg limit for manual cervical dislocation, and potentially at or near the 5 kg limit for mechanical devices. The limits exist because the effectiveness of cervical dislocation diminishes with increasing bird size, and the risk of an incomplete dislocation, resulting in pain and prolonged consciousness, rises accordingly.
• Reliability and operator skill. The HSA’s guidance states that cervical dislocation does not consistently concuss the brain and is unlikely to cause immediate insensibility.10 Even within the permitted weight range, it requires the bird to be firmly restrained and the head and neck positioned correctly. A welltrained operator working in controlled conditions can achieve reliable results, but the conditions on Sula Sgeir are far from controlled. The combination of difficult terrain, a large wild bird with a long and powerful neck, and the absence of any habituation to handling would make consistent, effective dislocation extremely difficult to achieve.
• Restraint stress is not mitigated. As with captive-bolt stunning, this method does not mitigate the welfare costs of capture and restraint. The period of handling required to position the bird correctly for cervical dislocation may in fact be longer than that required for the current method, increasing cumulative distress. Furthermore, the HSA’s guidance explicitly recommends cervical dislocation only in emergencies or for very small numbers of birds where no better method is available, and advises against its use as a routine slaughter method.10 The guga hunt is a planned, annual harvest of up to 500 birds: precisely the kind of routine operation for which the HSA does not recommend this method. This method is therefore unlikely to offer a welfare advantage over the current practice.

3. Shooting with firearms

The HSA’s own guidance recognises that firearms, used by appropriately trained and licensed personnel, may be necessary for the killing of individual, free-ranging birds under certain circumstances. The key welfare advantage would be the potential elimination of the capture and restraint phases. However, the application of this method on Sula Sgeir presents serious concerns:

• Wounding risk. Best practice requires that a shooter should only fire when confident of achieving a clean kill and should target one bird at a time. On exposed cliff faces with densely packed colonies, meeting these conditions consistently would be extremely challenging. Inexpert shooters or difficult shooting conditions are well recognised as a cause of wounding and significant suffering.
• Retrieval of wounded or killed birds. Birds shot on cliff edges would be at serious risk of falling into the sea or onto inaccessible ledges. Wounded birds who fell from cliffs could not be located and dispatched, resulting in prolonged suffering. Loss of birds would also presumably necessitate the killing of additional animals if the purpose is to provide birds for consumption.
• Disturbance to the wider colony. Repeated gunfire in a dense seabird colony would cause significant disturbance and panic among non-target birds, with potential for injury and nest abandonment. This disturbance would likely breach condition 4 of the licence granted for the hunt by NatureScot which requires that due care and attention be taken to avoid unnecessary disturbance to the gannet colony.

The welfare costs of capture and restraint

Whilst shooting addresses what we consider to be one of the most significant welfare concerns associated with the guga hunt: the stress and suffering caused by the capture and restraint of wild birds, captive bolt stunning and cervical dislocation do not.

It is well established that capture and manual restraint of wild birds triggers a pronounced acute stress response. Juvenile gannets on Sula Sgeir are wild, unhabituated birds with no prior contact with humans. Being seized around the neck by a pole-mounted device and physically handled would represent an intensely aversive experience causing significant distress to captured birds, irrespective of the killing method subsequently applied. It is probable that the restraint required to accurately and safely apply a captive bolt would require a longer period of pre-stun restraint, exacerbating this aspect of suffering associated with the hunt.

For any method requiring prior capture, this welfare cost is unavoidable.

Conclusions

While the HSA recognises the cultural significance attributed to the guga hunt, our assessment is that there is no method of killing that could be applied in the specific conditions on Sula Sgeir that would render the practice humane for all animals involved:

1. Non-penetrative captive-bolt stunning could theoretically deliver a more reliable killing method than the current technique, but the conditions on Sula Sgeir significantly increase the risk of mis-stunning, and captive-bolt application does not reduce the welfare costs of capture and restraint, in fact it could increase the impact of restraint.
2. Cervical dislocation could in principle offer a more standardised killing method, but juvenile gannets are at or near the upper weight limit for this technique, and the conditions on Sula Sgeir would make reliable application extremely difficult. As with captive-bolt stunning, the welfare costs of capture and restraint are not reduced.
3. Shooting could potentially eliminate the capture and restraint phase, but the serious risks of wounding, the inability to recover wounded birds on cliff terrain, and the disturbance to the wider colony make this approach unsuitable in this context.

The welfare concerns associated with the guga hunt are not solely, or even primarily, a function of the killing method employed. They are inherent to the practice of capturing and killing wild juvenile birds in the conditions that prevail on Sula Sgeir. Improving the method of killing, even if that were possible would, at best, address only one component of a process that causes suffering at multiple stages.

We would welcome the opportunity to discuss this assessment further with the Commission, and we remain available to provide any additional technical advice that may be helpful.

Yours sincerely,

Dr Huw Golledge
Chief Executive and Scientific Director Humane Slaughter Association