![]() ![]() narutobiei and its nursery areas.Ĭlimate change and anthropogenic disturbances can have significant and deleterious effects on coastal ecosystems and regional biodiversity. This research is a valuable resource to help guide science-based management, conservation and protection of the endemic Asian A. Obligate embryonic diapause during overwintering and seasonal migrations is a survival strategy that benefits the adults and neonates. Naru eagle rays are vulnerable to overfishing because of their low fecundity, long reproductive cycle and long time to reach sexual maturity. Fecundity ranged from 1 to 7 embryos per brood ( n = 158, mean ± SD = 3.36 ± 1.26) and was positively correlated with female disc width (linear regression F = 105.73, d.f. Mating occurs in August and September and gestation lasts approximately 12 months including a 9.5-month diapause that begins soon after mating and ends in June of the following year, leaving 2.5 months for embryos to complete development. Females have a single ovary and paired uteri, are viviparous, and reproduce via matrotrophic histotrophy. Both males and females reproduce annually and their reproductive cycles are synchronized and seasonal. Females mature at a larger size than males and require nearly twice as many years to reach maturity (DW50, 952.0 mm vs. To begin to fill these critical knowledge gaps, the reproductive life history of the Naru eagle was described. The long-term impacts of the predator control program on the population of rays and bivalves and their balance in the ecosystem are unknown because the life history of the Naru eagle ray has not been characterized. In response to decreased bivalve yields, the government initiated a predator control program and as a result, Naru eagle rays have faced intense and targeted fishing pressure during the last two decades. The East Asian endemic Naru eagle ray Aetobatus narutobiei is a large bodied ray whose estuarine habitat overlaps with an economically valuable bivalve fishery. 2Center for Bioinformatics & Computational Biology, University of Delaware, Newark, DE, United Statesīatoids comprise five of the seven most threatened families of sharks and rays.1Laboratory of Marine Zoology, Graduate School of Fisheries and Environmental Sciences, Nagasaki University, Nagasaki, Japan. ![]() Atsuko Yamaguchi 1* Keisuke Furumitsu 1 Jennifer Wyffels 2 ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |