Vertical distribution of macroplankton at the Charlie-Gibbs Fracture Zone (North Atlantic), as observed from the manned submersible ?Mir-1?

Small-scale distribution of deep-sea demersal nekton and other megafauna in the Charlie-Gibbs Fracture Zone of the Mid-Atlantic Ridge

“…The four MIR dives into the Charlie-Gibbs Fracture Zone are the first for that area and include the dive in MIR 1 reported by Vinogradov (2005). We were surprised by the prevalence of soft substrate on this mid-ocean ridge, as well as by the patchy high abundance of some fauna, such as the 'gardens' of sponges.…”

“…Submersibles have extended the range at which we can directly observe the natural history of deep-sea organisms, in particular their behavior (e.g., Cohen, 1977;Drazen et al, 2003;Uiblein et al, 2003) and small-scale distribution (e.g., Grassle et al, 1975;Smith and Hamilton, 1983;Kaufmann et al, 1989) when investigating deep-sea regions of rough topography such as ridges and volcanic island slopes (e.g.. Chave and Malahoff, 1998), hydrothermal vents (Gebruk et al, 2000) and in the open ocean (Vinogradov, 2005). Interactions of deep-sea organisms with their environment can be documented from videotapes taken from submersibles as well as by direct observations (Felley and Vecchione, 1994;Levin et al, 1994), providing insight into the environmental variables that affect the distribution of these forms.…”

The near-bottom plankton community at the Porcupine Abyssal Plain, NE-Atlantic: Structure and vertical distribution

“…One problem linked to net samples is an under-representation of gelatinous organisms, which are often destroyed during sampling, resulting in a gross under-estimation of zooplankton standing stocks. For example, during dives at the Charlie-Gibbs Fracture Zone, Vinogradov (2005) visually observed high densities of gelatinous Appendicularia houses close to the bottom, forming the most abundant group in this layer. Although the houses of Appendicularia are not caught in net samples, the animals are usually retained in the nets, but we cannot exclude that other gelatinous organisms have been missed.…”

Biodiversity Patterns and Processes on the Mid‐Atlantic Ridge

“…The highest densities of euphausiids were found in the upper 200 m. The gelatinous fauna, dominated by cnidarians, siphonophores, and appendicularians, was most abundant at 400 -900 m . In situ observations of gelatinous zooplankton revealed that different taxa occurred in distinct, and often narrow (tens of meters), depth layers (Vinogradov 2005 ;Youngbluth et al 2008 ). The most important contributors to the cnidarian biomass (wet mass) north of the SPF were the scyphomedusae Periphylla periphylla and Atolla spp.…”

“…population usually resided deeper in the water column than P. periphylla. Appendicularians were generally abundant at 450 -1,000 m and were observed to accumulate in the lowermost 50 m (Vinogradov 2005 ;Youngbluth et al 2008 ), suggesting that these feeding specialists (extremely small particles) are a prominent component of the benthopelagic zooplankton.…”