The role of temporal food limitation on development and mortality of Macoma balthica (L.) larvae
Bos, O.G.; Philippart, C.J.M.; van der Meer, J. (2005). The role of temporal food limitation on development and mortality of Macoma balthica (L.) larvae, in: Bos, O.G. Recruitment variation in Macoma balthica (L.): is there a role for larval food limitation?. pp. 85-101 In: Bos, O.G. (2005). Recruitment variation in Macoma balthica (L.): is there a role for larval food limitation? PhD Thesis. Rijksuniversiteit Groningen: Groningen. ISBN 90-367-2356-6. 160 pp., more |
Keywords | Availability > Food availability Biological development > Larval development Limiting factors Population functions > Mortality Temporal variations Macoma balthica (Linnaeus, 1758) [WoRMS] ANE, Southern Wadden Sea [Marine Regions] Marine/Coastal |
Abstract | Long-term observations (1973-2001) of populations of the intertidal bivalve Macoma balthica, in the western Wadden Sea, have suggested that larval mortality is strongly density-dependent. However, density-independent factors may also affect larval mortality. One possible source for such an effect is food limitation. To test this, laboratory experiments were run, where M. balthica larvae were reared under food limiting conditions, both quantitatively (high and low food level) and temporally (starvation during the first, second or third week). The results indicated that larvae offered high food levels grew fastest (6.4 µm d-1), and metamorphosed earlier (16.5 d) and at greater length (263 µm), than larvae subjected to low food level (4.3 µm d-1, 19.3 d and 244 µm, respectively). For both food levels, starvation in the first week resulted in a late metamorphosis at a large size, starvation in the second week resulted in an early metamorphosis at a small size, and starvation in the third week yielded intermediate results. Larval mortality was always lower in the low food condition but the timing of starvation had no impact on mortality. This suggests that larvae, in vivo, do not die directly from food limitation alone. The results are discussed with reference to models of metamorphosis. |
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