INVESTIGADORES
BALSEIRO Esteban Gabriel
artículos
Título:
When mating increases predation risk: the relationship between the flatworm Mesostoma ehrenbergii and the copepod Boeckella gracilis.
Autor/es:
TROCHINE, C.; MODENUTTI, BE; ESTEBAN GABRIEL BALSEIRO,
Revista:
ARCHIV FUR HYDROBIOLOGIE
Editorial:
E. Schweizerbart'sche Verlagsbuchhandlung
Referencias:
Año: 2005 vol. 163 p. 555 - 569
ISSN:
0003-9136
Resumen:
The zooplanktivorous flatworm Mesostoma ehrenbergii and the calanoid copepod Boeckella gracilis were observed to coexist in Patagonian fishless ponds. In laboratory experiments, we studied the vulnerability of B. gracilis to M. ehrenbergii Mesostoma ehrenbergii and the calanoid copepod Boeckella gracilis were observed to coexist in Patagonian fishless ponds. In laboratory experiments, we studied the vulnerability of B. gracilis to M. ehrenbergii Boeckella gracilis were observed to coexist in Patagonian fishless ponds. In laboratory experiments, we studied the vulnerability of B. gracilis to M. ehrenbergiiB. gracilis to M. ehrenbergii predation, testing the attack rates on copulating pairs and single adults in different abundances. We also determined B. gracilis dimorphism, sex ratio and copulating pair ratio on two occasions in a temporary pond, with and without M. ehrenbergii. Our results indicated that B. gracilis exhibited a male-skewed sex ratio irrespective of the presence of the predator. A marked dimorphism characterized this copepod species (females are about 40 % larger than males) and a large proportion of adults were observed participating in copulating pairs that lasted for days. M. ehrenbergii ate similar quantities of single males and females of B. gracilis but significantly more copulating pairs. The use of mucus threads allowed Mesostoma to ingest both members of the pairs instead of only one in most attacks. Larger prey may create more turbulence in the water while swimming, so the hydrodynamic signals produced by pairs should be greater than those produced by single individuals, making them more vulnerable. Besides, the attack rates obtained in the different prey abundances showed that encounter rate is the factor that determines M. ehrenbergii predation. We suggest that B. gracilis prolonged mating duration (days) is dangerous because it increases predation risk. B. gracilis dimorphism, sex ratio and copulating pair ratio on two occasions in a temporary pond, with and without M. ehrenbergii. Our results indicated that B. gracilis exhibited a male-skewed sex ratio irrespective of the presence of the predator. A marked dimorphism characterized this copepod species (females are about 40 % larger than males) and a large proportion of adults were observed participating in copulating pairs that lasted for days. M. ehrenbergii ate similar quantities of single males and females of B. gracilis but significantly more copulating pairs. The use of mucus threads allowed Mesostoma to ingest both members of the pairs instead of only one in most attacks. Larger prey may create more turbulence in the water while swimming, so the hydrodynamic signals produced by pairs should be greater than those produced by single individuals, making them more vulnerable. Besides, the attack rates obtained in the different prey abundances showed that encounter rate is the factor that determines M. ehrenbergii predation. We suggest that B. gracilis prolonged mating duration (days) is dangerous because it increases predation risk. M. ehrenbergii. Our results indicated that B. gracilis exhibited a male-skewed sex ratio irrespective of the presence of the predator. A marked dimorphism characterized this copepod species (females are about 40 % larger than males) and a large proportion of adults were observed participating in copulating pairs that lasted for days. M. ehrenbergii ate similar quantities of single males and females of B. gracilis but significantly more copulating pairs. The use of mucus threads allowed Mesostoma to ingest both members of the pairs instead of only one in most attacks. Larger prey may create more turbulence in the water while swimming, so the hydrodynamic signals produced by pairs should be greater than those produced by single individuals, making them more vulnerable. Besides, the attack rates obtained in the different prey abundances showed that encounter rate is the factor that determines M. ehrenbergii predation. We suggest that B. gracilis prolonged mating duration (days) is dangerous because it increases predation risk. B. gracilis exhibited a male-skewed sex ratio irrespective of the presence of the predator. A marked dimorphism characterized this copepod species (females are about 40 % larger than males) and a large proportion of adults were observed participating in copulating pairs that lasted for days. M. ehrenbergii ate similar quantities of single males and females of B. gracilis but significantly more copulating pairs. The use of mucus threads allowed Mesostoma to ingest both members of the pairs instead of only one in most attacks. Larger prey may create more turbulence in the water while swimming, so the hydrodynamic signals produced by pairs should be greater than those produced by single individuals, making them more vulnerable. Besides, the attack rates obtained in the different prey abundances showed that encounter rate is the factor that determines M. ehrenbergii predation. We suggest that B. gracilis prolonged mating duration (days) is dangerous because it increases predation risk. M. ehrenbergii ate similar quantities of single males and females of B. gracilis but significantly more copulating pairs. The use of mucus threads allowed Mesostoma to ingest both members of the pairs instead of only one in most attacks. Larger prey may create more turbulence in the water while swimming, so the hydrodynamic signals produced by pairs should be greater than those produced by single individuals, making them more vulnerable. Besides, the attack rates obtained in the different prey abundances showed that encounter rate is the factor that determines M. ehrenbergii predation. We suggest that B. gracilis prolonged mating duration (days) is dangerous because it increases predation risk. B. gracilis but significantly more copulating pairs. The use of mucus threads allowed Mesostoma to ingest both members of the pairs instead of only one in most attacks. Larger prey may create more turbulence in the water while swimming, so the hydrodynamic signals produced by pairs should be greater than those produced by single individuals, making them more vulnerable. Besides, the attack rates obtained in the different prey abundances showed that encounter rate is the factor that determines M. ehrenbergii predation. We suggest that B. gracilis prolonged mating duration (days) is dangerous because it increases predation risk. Mesostoma to ingest both members of the pairs instead of only one in most attacks. Larger prey may create more turbulence in the water while swimming, so the hydrodynamic signals produced by pairs should be greater than those produced by single individuals, making them more vulnerable. Besides, the attack rates obtained in the different prey abundances showed that encounter rate is the factor that determines M. ehrenbergii predation. We suggest that B. gracilis prolonged mating duration (days) is dangerous because it increases predation risk. M. ehrenbergii predation. We suggest that B. gracilis prolonged mating duration (days) is dangerous because it increases predation risk. prolonged mating duration (days) is dangerous because it increases predation risk.