Helminth communities of fish as ecological indicators of lake health

Abstract

This paper deals largely with the dynamics and changes in the helminth parasite communities of fish along the trophic gradient of lakes. The use of parasitological community data as a bioindicator of environmental health underlines the need to study parasite communities at comparable localities with known pollution levels. The comparison of the conditions in different habitats might be helpful to differentiate between normal fluctuations in ambient conditions and pollution-mediated effects. Therefore, the present study was designed to examine the community structure of parasites in snow trout (Schizothorax niger Heckel) inhabiting 3 lakes of contrasting trophic status in Kashmir. The idea of selecting the lakes, namely Anchar (strongly hypereutrophic), Dal (eutrophic) and Manasbal (mesotrophic) for this study was intentional as they depict different trophic gradients and exhibit the desirable pattern which was a prerequisite for this study. The findings presented in this article suggest an apparent lake-wise gradient in community structure, as the increase in trematode and cestode infections in Anchar was markedly greater, to levels clearly distinguishable from those in the other two water bodies. We conclude that human-induced eutrophication of lakes modifies the parasite community at component level and community-level studies on parasites may provide information on health status of lakes.

Variation in parasite communities and health indices of juvenile Lepomis gibbosus across a gradient of watershed land-use and habitat quality

“…Indeed, glochidia were absent in Gunn Creek, suggesting that freshwater clams may be infrequent or absent in this system; a similar trend was seen in pulp-effluent polluted lakes in Finland by Valtonen et al (1997). Increased nutrient loading associated with high proportions of agriculture may also facilitate an increase in snail density (Shah et al, 2013). This could explain the increase in Posthodiplostomum spp.…”

“…and Physella sp. as the first intermediate host (Hoffman, 1956), so increased abundance of this parasite may indicate an increase in number or density of snails (Shah et al, 2013). In contrast, the lifecycle of Actinocleidus sp.…”

“…Thus, if more snails found within a system, there is a higher potential for transmission. Shah et al (2013) noted increased densities of planorbid and lymnaeid snails in a eutrophic lake, and attributed elevated Diplostomum spp. levels in fish hosts from the area to increased densities and spatial distribution of snails.…”

Effects of Watershed Land Use on The Seasonal Energy Dynamics, Condition, and Parasite Communities of Stream Fish

“…Creek suggests potential alteration of invertebrate transmission pathways (Marcogliese 2004 Creek was absent of glochidium, suggesting that freshwater clams are infrequent or absent in this system; a similar trend was seen in pulpeffluent polluted lakes in Finland by Valtonen et al (1997). Increased nutrient loading associated with high proportions of agriculture may however create increased densities of snails (Shah et al 2013), which could potentially explain the increase in Posthodiplostomum ssp. prevalence and intensity with increasing habitat degradation compared to other species.…”

“…I anticipated areas with increased benthic diversity and lower watershed disturbance would have higher species diversity, a trend that has been demonstrated in previous research (e.g. Valtonen et al 1997;Shah et al 2013). In Chapter 4, the findings from Chapters 2 and 3 will be integrated and discussed, and potential avenues for future research and applications of results found here will be presented.…”