Stabilized length-weight relationship and pre-monsoon sscendency of jellyfish, Acromitus maculosus and Acromitus flagellatus in Kochi-backwaters, India
Raghavan, G.; Gokulan, N.C.; Matilda, M.V.; Narayana, S.V. (2025). Stabilized length-weight relationship and pre-monsoon sscendency of jellyfish, Acromitus maculosus and Acromitus flagellatus in Kochi-backwaters, India. Thalassas 41(2): 1-9. https://dx.doi.org/10.1007/s41208-025-00865-9
In: Thalassas. Universidad de Vigo: Vigo. ISSN 0212-5919; e-ISSN 2366-1674, meer
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| Auteurs | | Top |
- Raghavan, G.
- Gokulan, N.C.
- Matilda, M.V.
- Narayana, S.V.
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| Abstract |
Information on the length-weight relationships in Acromitus is limited to Acromitus hardenbergi. We report on the stabilized length-weight relationship in scyphozoan jellyfish, Acromitus maculosus and its congener Acromitus flagellatus from Kochi backwaters, India, and explain the environmental conditions influencing the ascendency of these species during the late pre-monsoon season. Weight stabilization experiments on fresh samples of A. maculosus indicated a progressive decline in medusa weight by 71%, 54% and 39% of the initial weight in the first 5, 10 and 15 min of the draining process. Small medusae (diameter < 120 mm) showed a higher relative weight loss at the stabilization point (75.7%) compared to large medusae (diameter > 120 mm), which exhibited a weight loss of 60.4%.For fresh specimens of A. maculosus, the estimated length-weight relationship prior to weight stabilization yielded a relatively low b-value of 1.453, while the weight stabilized medusa yielded more reliable b-value of 2.287. Both species showed negative allometric growth with b-values of 2. 287 for A. maculosus and 2.003 for A. flagellatus. The group means of the two species showed statistically significant variations in length-weight relationships. Despite noticeable inter-annual fluctuations in abundance, the condition factor of both species in the Kochi backwaters (KBW) was consistently high. This suggested that species abundance was influenced by optimal salinity conditions during their developmental stages, whereas the condition of these jellyfishes during late pre-monsoon was associated with food availability and other biotic factors. |
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