Vertical migration of Chaoborus flavicans in a Scottish loch

Abstract

The pattern of diel vertical migration of Chaoborus flavicans larvae in a shallow Scottish loch varies according to the instar and, in third and fourth instars, according to the season.The planktonic phase of the migration is not exclusively concerned with predation, the larvae feeding at least equally actively in the benthos. Although there is no conclusive evidence as to the role of vertical migration in Chaoborus flavicans, it has some of the characteristics of an epideictic display.Upward and downward locomotion can be induced experimentally in a plankton wheel by manipulating light intensity alone. However, the responses are complex and there is a great deal of individual variation, suggesting that additional factors are involved.

Day-Night Vertical Distribution and Feeding Patterns of Fourth Instar ofChaoborus Larvae in a Neotropical Reservoir (Socuy Reservoir, Venezuela)

“…This is consistent with results from other natural populations of larvae (GOLDSPINK and SCOTT, 1971;KAJAK and RYBAK, 1979;DURIEU and THOMAS, 1995;CROTEAU et al, 2003). Although, there has been some speculation that larvae might feed during benthic phase (GOLDSPINK and SCOTT, 1971;PAS-TOROK, 1980). Some authors, such as CROTEAU et al, (2003), think that it is difficult to imagine that mechano-receptors for prey movement would be effective when Chaoborus larvae are surrounded by sediment particles in bottom.…”

“…This vertical distribution pattern is very common in populations of fourth instar of many species of the genus Chaoborus (GOLDSPINK and SCOTT, 1971;FEDORENKO and SWIFT, 1972;LEWIS, 1977;FUKUHARA et al, 1993;ARCIFA, 1997;IRVINE, 1997, VOSS andMUMM, 1999;MCQUEEN et al, 1999;GLIWICZ et al, 2000). The vertical distribution pattern observed has been explained as result of a trade-off between fish predation risks, energetic cost of migration, and availability of food (SWIFT, 1976;DAWI-DOWICZ et al, 1990;TJOSSEM, 1990;BÜNS and RATTE, 1991;LOOSE and DAWIDOWICZ, 1994).…”

“…Differences in the proportion of crops with food between larvae populations, can be explained by differences in availability of prey (CHIMNEY et al, 1981), differences in migratory behavior and predation behavior of larvae (GOLDSPINK and SCOTT, 1971;SWIFT, 1976;HARE and CARTER, 1987;FUKUHARA et al, 1993), and variations in time of digestion of different kinds of prey at different temperatures (GIGUÈRE, 1981;MOORE, 1988).…”

Diel vertical migration patterns in two populations of Chaoborus flavicans larvae (Diptera: Chaoboridae) in response to fish kairomones

“…The larvae, especially 3 rd and 4 th instars, show marked DVM in environments with abundant fish (Stahl 1966;Teraguchi & Northcote 1966;Goldspink & Scott 1971;Luecke 1986), but not in environments with no or few fish (Northcote 1964;Carter & Kwik 1977;Luecke 1986). This suggests that the presence of fish is a factor that induces DVM.…”

Degree of high phenotypic plasticity in wild populations of Daphnia in early spring

“…The larvae that coexist with fish reside deeper in the water column or sediments during the daytime and migrate to upper layer at night, i.e., diel vertical migration (DVM, Teraguchi and Northcote, 1966;Dawidowicz et al, 1990;Tjossem, 1990). The migration amplitudes of the larvae vary by season; large migration amplitude is observed in summer while short or no migration occurs in winter and at low temperatures (Goldspink and Scott, 1971;Nagano et al, 2015). Given the impact of Chaoborus larvae on Daphnia, the larvae change distribution areas from sediment to water column in the daytime with simple age structure before summer.…”