Understanding Animal Infanticide: Survival Instincts and Causes

Why in the news?

A tigress in West Bengal’s Siliguri Zoo accidentally killed her three newborn cubs, spotlighting the complex reasons behind animal infanticide in both the wild and captivity.

Understanding Animal Infanticide: Survival Instincts and Causes

About  Resource Management and Survival Strategy:

  • Animals often reject or kill weak offspring to conserve resources for stronger cubs.
  • Zoos have witnessed numerous such incidents:
    • A lion cub in Kolkata’s Alipore Zoo was abandoned for being underweight in 2018.
    • In Jamshedpur (2013), a leopard abandoned her cub after 32 days, while another zoo leopard in Jhargram killed her cub after six weeks.
    • Tigress Zayana killed a stillborn cub in 2023 but raised her next healthy litter successfully in 2024.

Hormonal Imbalance and Inexperience

  • Hormonal issues post-delivery can disrupt maternal instincts, leading to aggression.
  • First-time mothers and those orphaned in their infancy are prone to mishandling cubs:
    • Lioness Kigali in Germany (2019) devoured her cubs, and a lioness in Indore Zoo accidentally killed three cubs in 2014.
    • Mothers can inadvertently harm cubs, like a tigress in Dublin Zoo (2019) who rolled over her cub, killing it.

Stress and Insecurity in Captivity

  • Stressful environments and perceived threats can trigger aggressive protective instincts.
  • Instances include:
    • A lioness in Hyderabad killed her cub upon encountering an unfamiliar keeper in 2012.
    • In Belgium (2013), a nervous lioness bit her vaccinated cubs to death.
  • Experts believe such behavior is instinctual, often misunderstood when seen through human perspectives.
  • In the wild, mothers might consume or relocate dead cubs to prevent predators from endangering surviving offspring.

Infanticide Involving Sexual Conflict: Key Points:

  • Infanticide often involves a killer (typically male) eliminating offspring to become the new sexual partner of the victim’s parent.
  • This behavior increases the killer’s reproductive fitness but decreases the parents’ fitness.
  • It reflects an evolutionary struggle between sexes, with victims developing counter-adaptations.
  • Females may also commit infanticide, often linked to competition for resources like food.

Sources Referred:

PIB, The Hindu, Indian Express, Hindustan Times