Benthic predation on eggs and larvae is significantly higher in the benthos than in the water column, conclude Allen & McAllister (2007) through experimental results. The loss rate measurements were made using agarose pellets flavoured with egg homogenate of planktonic and benthic invertebrates, as well as with live larval stages.
The result contrasts with previous mortality rate comparisons, which have suggested that predation on larvae in the plankton is much higher than predation on the benthos (e.g. Strathmann, 1985; Rumrill, 1990; Morgan, 1995).
The authors argue that while life-history models of benthic invertebrates incorporate estimates of pelagic mortality rates (e.g. Vance, 1973; Christiansen and Fenchel, 1979; McEdward, 1997; Levitan, 2000), they neglect the variable predation mortality ratio across the different habitats – pelagic and benthic. As a result life-history models may fail to predict strategies that will be evolutionarily favourable.
Jonathan D. Allen and Justin S. McAlister, 2007. Testing rates of planktonic versus benthic predation in the fieldm, Journal of Experimental Marine Biology and Ecology 347, p77-87
RELEVANT LINKS: Reviews of larval mortality rates -
- Morgan, S.G., 1995. Life and death in the plankton: larval mortality and adaptation. In: McEdward, L.R. (Ed.), Ecology of Marine Invertebrate Larvae. CRC Press, Boca Raton, pp. 279–321.
- Rumrill, S.S., 1990. Natural mortality of invertebrate larvae. Ophelia 32, 163–198.