Dolphins are highly specialized marine mammals, perfectly adapted to an aquatic existence. While they breathe air, requiring them to surface regularly, their entire physiology is designed for life in water. Being out of their natural environment, even for a short time, presents significant challenges to their survival.
Immediate Physiological Challenges
A dolphin’s large body weight, accustomed to the buoyancy of water, becomes a major burden on land. Without water to support them, gravity can compress their internal organs, including lungs and heart, making proper breathing and circulation difficult. This pressure can lead to organ damage and restrict lung inflation.
Their respiratory system, featuring a blowhole on top of their head, is suited for quick breaths at the water’s surface. Outside of water, the blowhole can be compromised, and the lack of hydrostatic pressure makes it harder to expand their lungs. Dolphins also generate significant body heat, easily dissipated in water. On land, their thick blubber traps this heat, leading to rapid overheating since they lack sweat glands to cool down.
The skin of a dolphin, accustomed to constant hydration, begins to dry out quickly when exposed to air. This desiccation can lead to cracking and blistering, making the skin vulnerable to infection. Direct sunlight further exacerbates this, causing sunburn and accelerating damage.
Factors Influencing Survival
Several elements can significantly alter how long a dolphin might survive out of water. Environmental conditions play a large role, with exposure to direct sunlight and high temperatures greatly reducing survival time. Conversely, being in shade, on wet and cool sand, or having human intervention to keep them wet can extend this period.
The individual dolphin’s condition also impacts its resilience. Calves and older dolphins are more vulnerable due to their less developed or declining physiological reserves. Underlying health issues, injuries, or chronic illnesses can severely compromise a dolphin’s ability to cope with stranding. Larger dolphin species face a higher risk of organ compression and overheating due to their greater mass, which can further shorten their survival time on land.
Consequences of Prolonged Exposure
If a dolphin remains out of water for an extended period, sustained pressure from gravity causes progressive organ failure. The crushing weight on their lungs and heart impedes their function, eventually leading to circulatory and respiratory collapse. Internal bleeding can also occur from this sustained pressure.
Despite living in water, dolphins can rapidly dehydrate on land. This dehydration leads to severe electrolyte imbalances, disrupting cellular functions. Prolonged exposure to air and sun causes extensive skin damage, resulting in severe drying, cracking, and open wounds. These skin lesions provide entry points for bacterial and fungal infections, which can quickly become systemic and life-threatening.
Prolonged immobility and pressure on specific body parts can also lead to muscle damage, including necrosis, where muscle tissue dies. Being stranded induces physiological and psychological stress, which further exacerbates organ dysfunction and reduces the dolphin’s chances of recovery.