J 2020

Planktivorous fish positively select Daphnia bearing advanced embryos

ZEMANOVÁ, Jana, Michal ŠORF, Josef HEJZLAR, Vanda ŠORFOVÁ, Jaroslav VRBA et. al.

Basic information

Original name

Planktivorous fish positively select Daphnia bearing advanced embryos

Authors

ZEMANOVÁ, Jana (guarantor), Michal ŠORF (203 Czech Republic), Josef HEJZLAR (203 Czech Republic), Vanda ŠORFOVÁ (203 Czech Republic, belonging to the institution) and Jaroslav VRBA (203 Czech Republic)

Edition

Marine and Freshwater Research, Clayton, CSIRO Publishing, 2020, 1323-1650

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10617 Marine biology, freshwater biology, limnology

Country of publisher

Australia

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

Impact factor

Impact factor: 2.070

RIV identification code

RIV/00216224:14310/20:00115592

Organization unit

Faculty of Science

UT WoS

000526573200009

Keywords in English

Cladocera; embryonal development; fish predation

Tags

Tags

International impact, Reviewed
Změněno: 10/11/2020 17:13, Mgr. Marie Šípková, DiS.

Abstract

V originále

The top-down effect of fish predation on reproduction success of Daphnia females was investigated in an outdoor mesocosm experiment with natural (oligotrophic) food conditions. The planktivorous fish, sunbleak (Leucaspius delineatus, 4.9 individuals m(-3)) was introduced into a half of mesocosms after the first sampling of zooplankton to compare daphnid life-history traits with and without fish predators. Our results showed selective fish predation on the daphnid females with advanced developmental stages of embryos. The Daphnia populations exposed to fish exhibited a lower proportion of females with advanced embryos over those with earlier embryonal stages. Fish predators obviously were attracted to more visible females bearing larger embryos, with well-developed pigmented eyes. Simultaneously, we found a smaller daphnid body length in the mesocosms with fish than in those that were fishless. However, the daphnid clutch size did not reflect their body-length pattern and, surprisingly, decreased regardless of fish presence or absence since the first sampling day, probably owing to deterioration of food quality (mean seston carbon : phosphorus ratio similar to 238). Nevertheless, this selective elimination of the females with advanced embryos, together with the overall decrease in daphnid fitness, can strengthen the deceleration of its population growth under fish predation.