Heat Stress in Game Birds: Prevention Tips for a Safe Summer June 9, 2026 Gamekeeping Heat stress in game birds is one of the few welfare risks that can escalate from manageable to serious within the space of a single hot afternoon. Pheasants and partridges cannot sweat, and panting is their only mechanism for shedding excess body heat. Once temperatures and humidity combine to overwhelm it, the window for intervention narrows fast. In pens where shade is limited and drinkers are undersized, the conditions for a welfare crisis can be present before the forecast has even changed. The practical measures that prevent it, shade provision, drinker capacity, stocking density, and pen ventilation, are all adjustable in advance during a well-prepared game rearing season. Here is what needs to be in place before the temperature climbs. Why Your Birds Struggle When Temperatures Climb Game birds are not built for British heatwaves. Unlike mammals, they cannot sweat, so panting is their primary mechanism for shedding body heat. As temperatures and humidity rise together, that mechanism becomes progressively less effective. Pheasants and partridges are non-domesticated species, more prone to stress than farmed poultry, as noted in the Department for Environment, Food & Rural Affairs (DEFRA) Code of Practice for the Welfare of Gamebirds. Under section 9 of the Animal Welfare Act 2006, the duty to provide adequate shelter, ventilation, and protection from suffering applies in hot weather as in any other conditions [1]. What Heat Stress Looks Like in Practice Knowing what to look for is the first step in catching a problem before it becomes serious. Birds experiencing heat stress will typically show some or all of the following signs: Persistent open-mouth panting with the beak held wide and the neck extended. Wings held away from the body to expose unfeathered skin and aid heat loss. Reduced movement and a reluctance to feed. Clustering in shade or near drinkers, with visible competition for water. Lethargy or collapse in acute cases. Partridges, in particular, can decline rapidly once heat stress sets in. Partridge welfare in summer deserves specific attention in pens with limited natural cover. Preventing Heat Stress in Release Pens This Summer Most cases of heat stress in a release pen are preventable. The risk becomes a welfare obligation when birds can no longer maintain their core temperature through normal behaviour and must rely on increasingly rapid panting. There is no single temperature threshold, as humidity, stocking density, and pen ventilation all interact, but the point of intervention is well before any bird mortality occurs. The four areas that matter are shade, water, stocking density, and airflow, and all four need to be in order before a hot spell arrives. Guidance from the Game & Wildlife Conservation Trust (GWCT) on optimising pheasant release pens recommends a mix of open ground, low cover, and roost-height vegetation, with a maximum of 1 bird per 10 m² [2]. Shade & Shelter in The Pen Game birds will seek shade instinctively but natural tree cover is rarely sufficient in a large pen during sustained heat. Supplementing with artificial shade, either along the pen perimeter or over feed and drinker stations, makes a measurable difference. Shelterflex sheeting is well-suited to this application, UV stabilised, 100% waterproof, and straightforward to fix to existing pen infrastructure. Running shade over drinker areas is a priority, as birds standing in direct sunlight to drink are already under additional thermal stress. Drinker Capacity & Water Placement Water consumption increases significantly during hot weather, and a drinker setup that works well in cooler months may fall short when temperatures rise. Check that capacity covers the full flock at peak demand and that drinkers are sited in shaded positions, as water left in direct sun heats rapidly and birds will avoid it. Automatic drinkers fed from a gravity or mains supply are the most reliable option in sustained heat. Our drinker range offers both automatic and hand-fill options, along with the accessories needed to maintain consistent water provision throughout the day. Stocking Density & Pen Layout High stocking density compounds heat stress risk because birds generate body heat, and in a crowded pen section, that heat accumulates. Ensure the layout allows birds to spread out, that no single area becomes a bottleneck, and that sections with poor airflow are kept open rather than closed off during prolonged hot periods. Cover Crops Shop Now Shelterflex Waterproof Sheeting Shop Now Drinkers Shop Now Game Rearing Essentials Shop Now What to Do If You Spot Heat Stress in Your Birds If birds are showing signs of acute distress, act immediately. DEFRA guidance is clear that a welfare problem is likely before bird losses are seen, which means the keeper must read the behaviour and intervene early. Respiration rate can increase by up to ten times the resting rate, and heavy panting tires birds and reduces their capacity to cope with extended hot weather [3]. Work through the following in order: Move or shade affected birds immediately, away from direct sun and out of crowded areas. Ensure fresh, cool water is accessible and check that automatic systems are flowing correctly. Increase airflow through the pen where possible by opening any closeable sections. Reduce activity around the pen, as repeated disturbance raises core body temperature further. Contact your vet if birds are collapsed or unresponsive. Prepare the Pen Before the Forecast Changes A hot week in July with underprepared shade and drinkers running low is difficult to manage from the middle of it. Get those variables right in advance, and the same forecast becomes a manageable week rather than a welfare crisis. Collins Nets has supplied gamekeepers, estates, and game farms across the UK for over 35 years. Our game rearing essentials range covers drinkers, feeders, and Shelterflex sheeting for pens of any size, with expert team support available if you need help speccing the right setup for your ground. Call 01308 485422 or use the contact form to speak to the team Monday to Friday, 7.30am to 4.00pm. External Sources [1] GOV.UK, Department for Environment, Food & Rural Affairs (DEFRA), Guidance, Code of Practice for the Welfare of Gamebirds Reared for Sporting Purposes (2023): https://www.gov.uk/government/publications/code-of-practice-for-the-welfare-of-gamebirds-reared-for-sporting-purposes/code-of-practice-for-the-welfare-of-gamebirds-reared-for-sporting-purposes [2] Game & Wildlife Conservation Trust (GWCT), Alex Keeble, Optimising Your Pheasant Release Pens (2025): https://www.gwct.org.uk/blogs/news/2025/july/optimising-your-pheasant-release-pens/ [3] GOV.UK, Department for Environment, Food & Rural Affairs (DEFRA), Heat Stress in Poultry, Solving the Problem (2005): https://assets.publishing.service.gov.uk/media/5a7990d2ed915d07d35b67de/pb10543-heat-stress-050330.pdf Further reading « Golf Practice Net UK Guide to Building at Home or Your Club June 4, 2026
