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The present work was carried out to study the demographic aspects of Cyprinus carpio, an invasive species and an ecological pest capable of universal existence. Data on length–frequency was obtained from the two varieties of C. carpio from the deepest freshwater lake of India, Manasbal Lake, over a time period of 1 year (March 2019–February 2020) and analysed using the FiSAT‐II software. The mean total length was reported to be 18.58 cm for C. carpio var. communis and 19.18 cm for C. carpio var. specularis, with the dominant length groups being 20–21 and 19–20 cm, respectively. The length–weight relationship parameters yielded the equation logTW = (2.56) logTL − 1.30, r = 0.94, for C. carpio var. communis, with a condition factor (K) value of 1.42 ± 0.25, and logTW = (2.53) logTL − 1.26, r = 0.93 for C. carpio var. specularis, with a condition factor (K) value of 1.38 ± 0.20. Different parameters obtained from the von Bertalanffy growth equation included L∞ = 38.85 cm; K = 0.170/year; ø′ = 2.409 and t0 = −0.93 for C. carpio var. communis, and L∞ = 30.45 cm; K = 0.210/year; ø′ = 2.289 and t0 = −0.80 for C. carpio var. specularis. The mortality parameters, including total, natural and fishing mortality, were also estimated for C. carpio var. communis to be Z = 0.08, M = 0.40 and F = −0.32, and for C. carpio var. specularis, to be Z = 0.22, M = 0.49 and F = −0.27, respectively. The exploitation rate (E) estimated for both varieties revealed its very less exploitation, suggesting more efficient methods to explore Manasbal Lake to its full capacity and to determine proper measures needed to be taken to conserve the native fauna. [ABSTRACT FROM AUTHOR]

The present paper is a review of the available literature on the significance of forage fish, the plethora of services they provide, and the threats faced by them. Forage fish are pelagic planktivorous species that operate as conduits of energy between the lower trophic level (plankton) and the upper trophic level (predators). A variety of ecosystem services are provided by them, from serving as prey for higher trophic levels to producing fish meal and oil. Forage fish have a consumption value for humans and cultural importance to many societies. Forage fish have faced constant natural and anthropogenic threats in the past, resulting in numerous fish collapses which subsequently impacted their predators. The economic benefit provided by forage fish has been estimated to be approximately $ 18.7 billion per annum. An introspection of the data on ecosystem services revealed lack of data on regulating and cultural services, eventually leading to a monetary underestimation and their commercial prioritization over the wider benefits they provide. [ABSTRACT FROM AUTHOR]