[DOWNLOAD] "New Distribution Record and Ecological Notes of the Freshwater Hydrozoan Craspedacusta Sowerbii in Southeast Texas." by The Texas Journal of Science ~ Book PDF Kindle ePub Free
eBook details
- Title: New Distribution Record and Ecological Notes of the Freshwater Hydrozoan Craspedacusta Sowerbii in Southeast Texas.
- Author : The Texas Journal of Science
- Release Date : January 01, 2002
- Genre: Engineering,Books,Professional & Technical,
- Pages : * pages
- Size : 184 KB
Description
Abstract. -- Craspedacusta sowerbii, the only species of freshwater cnidarian exhibiting a medusa stage in it's life cycle, was collected from an excavated pond in Jefferson County, Texas from 6 July to 12 November 2001. Density was patchy and mean density per collection date varied from 0.59/[m.sup.3] to 34.43/[m.sup.3]. The highest density from a single plankton tow was 121.32/[m.sup.3]. Five polyps were collected from artificial substrates suspended in the water column, indicating that sexual reproduction had occurred. The medusae disappeared when the temperature decreased to 21[degrees]C even though the zooplankton food supply was still abundant. **********