A length class model of the population dynamics of the Antarctic KrillEuphausia superbadana

✍ Scribed by H. Astheimer

• Publisher: Springer
• Year: 1986
• Tongue: English
• Weight: 614 KB
• Volume: 6
• Category: Article
• ISSN: 0722-4060
• DOI: 10.1007/bf00443399

✦ Synopsis

In a location-independent simulation, Krill frequency and weight are modelled in 0.5 mm length classes. Population dynamics are defined by time-and length-dependent birth, growth and death rates. In a steady state (constant death rate of 98.7% p. a.) Krill frequency and weight oscillate by a factor of 32 and 3, respectively. Larval catch curves from German Antarctic Expeditions and published mortality rates for older Krill suggest a hyperbolic form of the survival function with age (i.e. mortality decreases with increasing body length). A Krill fishery can be simulated indirectly through manipulation of the mortality rate or through direct elimination of individuals. For example, a complete elimination of the upper length classes does not lead to extinction even if performed each year before the spawning season, as long as the size at first capture is greater than 45 mm. The Antarctic Krill seems to be a classical example of r-selection with its high fertility, high mortality and large stock fluctuations.