Opportunistic sighting of a Sperm Whale Physeter macrocephalus Linnaeus, 1758 in Lakshadweep Archipelago

Abstract

The Sperm Whale Physeter macrocephalus Linnaeus, 1758 is a large-sized toothed marine mammal belonging to the order Cetartiodactyla and family Physeteridae. It is the only living species of the genus Physeter (Mittermeier & Wilson 2014). It is the world’s largest toothed whale having the biggest brain of any animal species (Marino 2004). This species is characterised by a very large and rounded head which hold large quantities of a waxy substance known as spermaceti; the blowhole opens at angle from the left side of nasal passage; body colour is deep black to brownish-gray above with white markings around lips; instead of a dorsal fin, this species has distinct thick, low, and triangular humps (Jefferson et al. 1993; Menon 2014). It may live alone, or in small groups of 20–40 individuals or more in greater than 1,000 m deep oceans and undertake extensive migration (Taylor et al. 2019). Their distribution range is from Antarctic and cold-temperate waters (Northern hemisphere) to tropical waters (Mittermeier & Wilson 2014). In India, this species has been recorded all along the coastal states of Gujarat, Karnataka, Kerala, Tamil Nadu, Puducherry, Andhra Pradesh, Lakshadweep Islands, and Andaman & Nicobar Islands (Kumarran 2012; Marine Mammals of India database 2022).