Abstract
Trophological studies of ctenophore Mnemiopsis leidyi conducted in the Caspian Sea more often included species at the later stage of development, as a result, juveniles, metamorphic larvae and larvae were ignored. Ctenophore is known to start feeding since the moment the larva emerges from the egg. Studying the availability of food resources and their size range allowed to trace a certain dependence in the diet of ctenophore, and to determine at which stage of development the jellylike organism in the population feeds most intensively. During the period of naturalization of invasion in the Caspian Sea (1998-2016) there has been registered an increasing number of species with an empty gastrovascular cavity (GVC) in the Mnemiopsis population. According to the analysis results obtained during the study period, the share of individuals with empty GVC 
 in the North Caspian increased to 77.8%, which is associated not with the climatic or hydrological factors, as in 2015 and 2016, but with the availability of food items and internal competition for food resources. There has been found the diversity of the items making food stuff of Mnemiopsis in nature. The main food component is mesozooplankton, as well as meroplankton (cirriped nauplii, larvae of polychaete worms). In food requirements ctenophore does not show selectivity of food resources, the basis of its food make the most available forms of zooplankters.
Highlights
Trophological studies of ctenophore Mnemiopsis leidyi conducted in the Caspian Sea more often included species at the later stage of development, as a result, juveniles, metamorphic larvae and larvae were ignored
Ctenophore is known to start feeding since the moment the larva emerges from the egg
Studying the availability of food resources and their size range allowed to trace a certain dependence in the diet of ctenophore, and to determine at which stage of development the jellylike organism in the population feeds most intensively
Summary
ТРОФОЛОГИЯ ГРЕБНЕВИКА MNEMIOPSIS LEIDYI ПОСЛЕ НАТУРАЛИЗАЦИИ В ЭКОСИСТЕМЕ КАСПИЙСКОГО МОРЯ. Трофологические исследования гребневика Mnemiopsis leidyi, проводившиеся в акватории Каспийского моря, в основном охватывают организмы, достигших стадии развития «взрослая особь». Ранее трофологические исследования гребневика Mnemiopsis leidyi в акватории Каспийского моря охватывали особей, достигших стадии развития «взрослая особь», оставляя без внимания молодь, метаморфирующих личинок и личинок, вышедших из яйца. Сбор трофологического материала по оценке таксономического состава гастроваскулярной полости (ГВП) гребневика проводился в местах максимальных скоплений Mnemiopsis leidyi на акватории Северного, Среднего и Южного Каспия, где было отобрано на анализ 222 ГВП у гребневиков, общий размер которых составлял от 10 до 40 мм (2015 г.), 38 ГВП у гребневиков размером от 6 до 20 мм (2016 г.) [7] и 1 807 ГВП гребневиков размером от 0,2 до 35 мм (2019 г.). Средние значения экстерьерных характеристик Mnemiopsis leidyi, отловленного в 2015, 2016 и 2019 гг. в основных районах Каспия
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: Vestnik of Astrakhan State Technical University. Series: Fishing industry
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.