Long-term changes in invertebrate size structure and composition in a boreal headwater lake with a known minnow introduction

Abstract

To

First human impacts and responses of aquatic systems: A review of palaeolimnological records from around the world

“…In some cases, invasions by less well-preserved taxa can be inferred by tracking the patterns of change in other taxa. For example, the introduction of fish in formerly fishless lakes can be tracked based on the abundance, size and morphology of the invertebrate predator Chaoborus and its prey Bosmina (Labaj et al, 2013). Determining the degree to which biological invasions drive ecosystem change, or are a response to changes driven by other factors such as catchment disturbance, eutrophication or pollution, is an important question for biological invasion science, and one that palaeoecology, with its capacity to extend temporal perspectives, is in a strong position to answer (Kamenova et al, 2017; Willis and Birks, 2006).…”

Multi-trophic level response to extreme metal contamination from gold mining in a subarctic lake

“…In Pocket Lake, Chaoborus mandibles were recovered in low abundances (less than 10 per interval) throughout the sediment core, including both the pre-, peak and post-mining periods, and no notable changes in biomass or productivity of these macroinvertebrate predators on Daphnia can be inferred in response to metal(loid) contamination. Furthermore, the large-bodied species Chaoborus americanus and Chaoborus trivattatus were recovered throughout, suggesting Pocket Lake has probably always been fishless, as C. americanus is a well-known indicator of fishless (or very low planktivorous fish) conditions, and C. trivattatus, which often coexists with C. americanus, generally dominates in lakes with minimal fish community [70]. The recovery of remains of these taxa at low, but consistent, abundances throughout the sediment core suggests that Pocket Lake has not undergone changes in fish community, and has most probably been fishless over the recent past, including the period of intense contamination from mining operations.…”

Topical advances and recent studies in paleolimnological research

“…Fossil invertebrate remains reveal information about food-web structures, predatorprey dynamics, and they are useful for investigating the influence of invertebrate competition and predation on zooplankton size structure (Alexander and Hotchkiss, 2010). Invertebrate remains have been used to document the presence or absence of fish, often for specific fish families (e.g., Cyprinidae), to identify changes in fish planktivory, and to examine keystone fish predation (Palm et al, 2011;Tolonen et al, 2012;Twining and Post, 2013;Labaj et al, 2013). The use of these fossils to address aquatic trophic-web questions often relies on contemporary limnological information about zooplankton community structure in lakes with and without fish.…”