Abundance, biomass, and size frequency distribution of an arctic ctenophore, mertensia ovum (fabricius) from frobisher bay, Canada
1989; Taylor & Francis; Volume: 74; Issue: 2 Linguagem: Inglês
10.1080/00364827.1989.10420527
ISSN1503-1128
Autores Tópico(s)Cephalopods and Marine Biology
ResumoAbstract Mertensia ovum is important in the zooplankton of Frobisher Bay, eastern Canadian Arctic. Unlike ctenophore populations in temperate waters, which are often ephemeral, this one is stable in both numbers and size composition. Densities exceeding 5 animals/100 m3 were always present. However, abundance and biomass were at least 2-3 orders of magnitude lower than the maxima of many temperate species. Fewer than 1% of all the samples collected in the inner bay contained more than 38 animals/100 m3. Samples collected in the outer bay had as many as 200 animals/100 m3 with most of the population within the upper 100 m. In the inner bay, the mean abundance per unit area in the upper 50 m, during several open water seasons, ranged from 2-6 animals/m2, while the biomass varied from 0.2-0.4 g dry weight/m2 (H g wet weight and 0.3-0.8 kcal/m3). In winter, adults are present under the ice in numbers comparable to those in summer, however, they do not appear to congregate just below the ice to prey upon the sub-ice community. Spawning probably begins in spring and early summer and may continue through the summer and into the fall.
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