When Whales Collide: Crittercam Offers Insight into the Competitive Behavior of Humpback Whales on Their Hawaiian Wintering Grounds

Abstract

Despite years of study, the humpback whale mating system remains an enigma. Sustained observations of subsurface behavior may help reveal important components of the mating system. In 2005 and 2006, we deployed Crittercam, an animal-borne imaging and data-logging tool, on humpback whales in their winter grounds. We focused our efforts on competitive groups, believed to be the epicenter of mate selection. Over 27 days of fieldwork in Maui waters we deployed 10 front- or rear-facing Crittercams on escorts (males) in competitive groups. This work revealed: (1) Five whales swimming to depths of over 150 m, with one animal diving down 298 m; (2) Instances of competitive behavior (inflated pleats, chasing) occurring along the seafloor; (3) The displacement of a primary escort (the whale closest to the female) by a challenger; (4) A detailed time budget of one principal escort maintaining his position over a 73-min observation window; (5) Threats and body strikes between secondary escorts; (6) Apparent affiliative behavior by females, including possible pectoral fin stroking of a principal escort and drafting in a principal escort's pressure wave; and (7) A secondary escort resting on the bottom while sculling its pectoral fins through the substrate, throwing up clouds of sand. In summary, Crittercam allowed us to observe diving behavior and sustained micro-interactions between animals in competitive groups occurring far below the surface. Such observations can have significant bearing on interpretation of the mating system by assisting in uncovering behaviors that may be involved in mate guarding, dominance hierarchies, and female choice.

Behavioural strategies in humpback whales,Megaptera novaeangliae, in a coastal region of Brazil

“…Similar observations in humpback whales and other cetaceans also suggest this (Silverman & Dunbar, 1980;Tyack & Whitehead, 1983;Baker & Herman, 1984;Clapham et al, 1992;Herman et al, 2007). Escorts, in humpback whales, engage in agonistic interactions (aggressive conduct) more frequently in larger competitive groups (four or more whales together and mother and calf and more than two escorts) than in smaller competitive groups (three adult whales together and mother and calf and two escorts).…”

Risk behaviours exhibited by free‐roaming cats in a suburban US town

“…Animal-borne video systems have been previously used to study habitat use, food habits and general animal behaviour in a variety of species including: marine mammals, sea turtles, penguins and lions (Ponganis and others 2000, Heithaus and others 2002, Hays and others 2007, Herman and others 2007, Moll and others 2007). These Crittercam video systems record an animal-eye view of activities without disrupting behaviour.…”

The reproductive ecology of resident manta rays (Manta alfredi) off Maui, Hawaii, with an emphasis on body size

“…For example, female bison (Bison bison) seek to replace a lower-ranking, tending male by running away from him and towards higher-ranking males, usually resulting in her tending male being replaced by one of higher rank (Wolff 1998). Humpback whales (Megaptera novaeangliae) also engage in similar behavior, in which two or more males (sometimes 20 or more), compete physically for the primary escort position closest to the female (Tyack and Whitehead 1982;Baker and Herman 1984;Herman et al 2007). In humpback whales, the primary escort is typically the largest male in the group (Spitz et al 2002).…”