Abstract

Ocean navigation is notoriously difficult, with complex currents and the absence of landmarks conspiring to create considerable uncertainty of one’s position. The tragic loss of almost 2000 lives near the Isles of Scilly in 1707 offered a stark reminder, sparking the 1714 Longitude Act that encouraged a solution to this problem. John Harrison’s extraordinary marine chronometer subsequently heralded an age of safer human seafaring. Many marine animals undertake spectacular migrations, despite their lack of such technological aids: marine turtles undertake long distance solo migrations to remote island nesting beaches; whales routinely navigate across an ocean basin between feeding and breeding grounds. In this talk I will describe some modelling of these phenomena. In the context of turtles, I will explore the challenge faced by a solo navigator as it attempts to return to a small target in the middle of the ocean and show how exploiting multiple sources of navigating information proves optimal. In the context of whale navigation I will consider the role played by collective information and the degree to which this can improve navigation, as well as the particular challenges faced by whales as our oceans become increasingly polluted by noise.