The Trophic Role of Diporeia (Amphipoda) in Colpoys Bay (Georgian Bay) Benthic Food Web: A Stable Isotope Approach

Life history, distribution, and production of Diporeia near the Keweenaw Peninsula Lake Superior

“…Sly and Christie (1992) found a strong correlation between Diporeia abundance and sediment organic carbon, bacteria, and sediment redox potential in samples from Lake Ontario collected from 27 to 56 m. In contrast, Dermott (1978) found Diporeia to have a strong inverse relationship with depth, but only weak associations with sediment grain size and organic content in Lake Superior (no data were given on the complete depth strata sampled). This result is supported by the findings of Verhamme and Auer (2009) who reported that slope and profundal habitats exhibiting major differences in Diporeia abundance did not show consistent differences in sediment richness (e.g., bacteria numbers and sediment oxygen demand, an integrator of sediment Table 3 Diporeia length-weight and production characteristics in the shelf, slope, and profundal regions of the HN transect, Lake Superior, 2003, compared to those of Guiguer and Barton (2002) for Lake Huron and Winnell and White (1984) microbial activity). Noting that the high rates of primary production occur in the nearshore waters of Lake Superior in spring, Auer et al (2009) suggested that it was the rate of delivery to and transport through the slope that helped maintain amphipod peaks there.…”

“…present-day conditions in the other Great Lakes). Studies of Diporeia in the Great Lakes often focus attention on amphipod depth distributions (e.g., Evans et al 1990, Winnell and White 1984, and Guiguer and Barton 2002. In our study, peaks in Diporeia density occurred at a depth of 64 m in May through August, expanding to depths of 64 to 125 m in September and October (Fig.…”

“…Diporeia has historically been the most abundant benthic invertebrate in the offshore water (N30 m) of the Great Lakes. Its life history information is less well described for Lake Superior than for the other Great Lakes (Eggleton 1937;Winnell and White 1984;Nalepa et al 2000;Dermott 2001;Guiguer and Barton 2002). The amphipod phylogroup Diporeia has been the subject of much study because of their critical link to the fishery and their recent precipitous decline in all of the Great Lakes except Lake Superior.…”

Uptake of sedimentary organic matter by the deposit-feeding Baltic amphipods Monoporeia affinis and Pontoporeia femorata

“…Stable isotope ratios, e.g. δ 13 C and δ 15 N, are other common tracers in food web research, and can use either natural variations in isotopic ratios (Owens 1987, Guiguer & Barton 2002 or manipulated ratios (Levin et al 1999). Enrichment with the heavy isotope is often used in nutrition studies (e.g.…”

Reproduction disorders in the benthic amphipod Monoporeia affinis: an effect of low food resources

“…Later studies on Diporeia spp., a closely related North American freshwater species, have shown that gut fullness declines after the spring bloom, but increases later in the autumn (Guiguer & Barton 2002). Between periods of phytoplankton blooms, the amphipods can cope without food or subsist on low-quality food by using energy stored as lipids, facilitated herein by the low temperatures in their soft-bottom habitat.…”