What causes a house mouse to die? - briefly
Acute mortality stems from predation, poison ingestion, extreme temperatures, dehydration, and starvation. Chronic death results from infections, parasitic infestations, and organ failure.
What causes a house mouse to die? - in detail
Mortality in the common house mouse results from a range of physiological, environmental, and anthropogenic factors. Understanding these mechanisms helps in assessing population dynamics and designing effective control measures.
Pathogens are a primary source of death. Bacterial infections such as salmonellosis and streptococcal septicemia can overwhelm the immune system. Viral agents, notably mouse hepatitis virus and lymphocytic choriomeningitis virus, cause systemic disease that often proves fatal. Parasitic infestations—including mites, fleas, and intestinal nematodes—lead to anemia, malnutrition, and secondary infections.
Poison exposure accounts for a significant proportion of lethal events. Anticoagulant rodenticides (e.g., warfarin, brodifacoum) interrupt the vitamin K cycle, resulting in uncontrolled bleeding. Acute neurotoxins such as bromethalin and zinc phosphide disrupt cellular respiration, causing rapid organ failure. Sublethal doses may accumulate, producing chronic toxicity that eventually proves fatal.
Physical trauma and environmental stressors also contribute. Predation by cats, birds of prey, and snakes inflicts injuries often incompatible with survival. Accidental injuries—compression, burns, or entrapment in machinery—are common in urban settings. Extreme temperatures, either hyperthermia in hot, poorly ventilated areas or hypothermia during cold spells, can induce fatal metabolic collapse.
Nutritional deficiencies and starvation occur when food sources become scarce or contaminated. A diet lacking essential amino acids, vitamins, or minerals impairs organ function and weakens resistance to disease. Inadequate water intake exacerbates dehydration and renal failure.
Collectively, these causes illustrate the multifactorial nature of mortality in this species, highlighting the interplay between biological agents, chemical hazards, physical injuries, and environmental conditions.