Regulation of rotifer species by invertebrate predators in a hypertrophic lake: Selective predation on egg-bearing females and induction of morphological defences

TY - JOUR

T1 - Regulation of rotifer species by invertebrate predators in a hypertrophic lake: Selective predation on egg-bearing females and induction of morphological defences

AU - Conde-Porcuna, J-M.

AU - Declerck, S.

N1 - WOS:000073780300001 ISI Document Delivery No.: ZP706 Times Cited: 30 Cited Reference Count: 45 Conde-Porcuna, JM Declerck, S Conde-Porcuna, Jose/L-9665-2014; Declerck, Steven/E-4338-2010 Conde-Porcuna, Jose/0000-0002-5074-2796; Declerck, Steven/0000-0001-6179-667X 32 0 10 Oxford univ press Oxford 8

PY - 1998

Y1 - 1998

N2 - Temporal changes in the biomass of rotifer plankton were examined in a shallow hypertrophic lake during 1 month (April/May), when the predatory rotifer Asplanchna brightwelli develops. The abundance of herbivorous rotifers was regulated by predation from A.brightwelli and from the copepod Acanthocyclops robustus. The densities and fecundity rates of Keratella cochlearis and Keratella quadrata were negatively related with the biomass of predators. Stomach analyses showed that Asplanchna fed selectively on reproductive females of K. cochlearis, reducing the fecundity of this species. Predators induced longer caudal spines in K. quadrata, which were negatively related to the fecundity of this rotifer, suggesting a reproductive cost associated with spine production. In contrast, spine length of K. cochlearis was not related to predators, but to temperature. These results showed that predators can reduce rotifer densities through increasing mortality and through decreasing rotifer fecundity rates regardless of phytoplankton biomass. We also show that morphological defences of K. cochlearis and K. quadrata are induced in different ways.

AB - Temporal changes in the biomass of rotifer plankton were examined in a shallow hypertrophic lake during 1 month (April/May), when the predatory rotifer Asplanchna brightwelli develops. The abundance of herbivorous rotifers was regulated by predation from A.brightwelli and from the copepod Acanthocyclops robustus. The densities and fecundity rates of Keratella cochlearis and Keratella quadrata were negatively related with the biomass of predators. Stomach analyses showed that Asplanchna fed selectively on reproductive females of K. cochlearis, reducing the fecundity of this species. Predators induced longer caudal spines in K. quadrata, which were negatively related to the fecundity of this rotifer, suggesting a reproductive cost associated with spine production. In contrast, spine length of K. cochlearis was not related to predators, but to temperature. These results showed that predators can reduce rotifer densities through increasing mortality and through decreasing rotifer fecundity rates regardless of phytoplankton biomass. We also show that morphological defences of K. cochlearis and K. quadrata are induced in different ways.

KW - fresh-water zooplankton keratella-cochlearis community structure reproductive costs asplanchna-girodi daphnia-pulex body-size chaoborus copepods populations Marine & Freshwater Biology Oceanography

U2 - 10.1093/plankt/20.4.605

DO - 10.1093/plankt/20.4.605

M3 - Article

SN - 0142-7873

VL - 20

SP - 605

EP - 618

JO - Journal of Plankton Research

JF - Journal of Plankton Research

IS - 4

ER -