Benthic species

Another possible example of endocrine disruption in situ relates to the hndings of Moore and Stevenson" of altered sex ratios and intersex harpacticoid copepods in the vicinity of Edinburgh s long sea sewage outfall. Intersexiiality is common in some crustaceans but is extremely rare in harpacticoid copepods. There was no relationship between the frequency of intersex and distance from the most contaminated sites and nor was there evidence that other benthic species had been adversely affected. Additional work is required to prove conclusively that endocrine disruption is involved in this case. 

Roach (rutilus rutilus), a medium-sized cyprinid fish, is a planktonic and benthic species, feeding mainly on cladocerans (D. longispina), detritus, plant debris, amphipods (Echinogammarus sp.), filamentous algae, and ostracods. Roach can thrive on poor quality, even polluted water and displays more capacity of adaptation to different kinds of food than rudd [62]. 

Insects immature benthic species whole from copper-contaminated river up to 60 km downstream from outfall (779 mg Cu/kg DW sediments) vs. reference site (18 mg Cu/kg DW sediments)... 

O2 levels of the waters feeding this upwelling area are likely to contribute to an expansion in the intensity and vertical extent of its hypoxic zone. An important consequence would be a loss of oxygenated habitat in the underlying shelf and slope ecosystems resulting in a widespread mortality of benthic species. 

Voorspoels, S., Covaci, A., Maervoet, J., De Meester, I. and Schepens, P. (2004). Levels and profiles of PCBs and OCPs in marine benthic species from the Belgian North Sea and the Western Scheldt Estuary, Marine Pollution Bulletin, 49 393-404. 

A number of benthic species are highlighted in the Ontario EEM reports as indicators of pollution because they were considered either more or less sensitive to impacts that may be found in association with pulp and paper mills (Borgmann et al., 2002). Organisms that have shown significant differences in their abundance... 

The expansion of anoxic and hypoxic zones has dramatically increased in recent years and the ecological consequences on pelagic and benthic species can be severe. 

The introduction of other organisms may be regarded as positive events. Benthic species such as mya and anadara widely spread over the regions with low oxygen contents unfavorable for other benthos representatives they provided valuable food resources for benthofagous fish, while their larvae are consumed by small pelagic fish. The role of the fouling species Balanus im-... 

The penetration of Mediterranean migrants did not damage the Black Sea ecosystem on the contrary, due to the insertion of these planktonic and benthic species, new edible organisms were added. 

The currents via the Bosporus Strait delivered 59 species of zooplankton, 37 species of phytoplankton, 51 benthic species, and 23 species of macrophytes. Meanwhile, it seems probable that some of the species recognized during the recent years have not been noted previously because of the absence of appropriate studies in the near-Bosporus region aimed at the groups of species mentioned. 

Cahbration for benthic species is somewhat more uncertain. The first comprehensive calibration was carried out by Yair Rosenthal, then at MIT, who used Cibicidoides spp. from shallow sediments on the Bahamas outer bank to calibrate benthic magnesium between 5 °C and 18 °C (Rosenthal et al., 1997). When this calibration is augmented with C. wuellerstorfi data from deeper... 

The aims of the study were 1) implementation of an analytical method for measuring Tc in environmental samples, and 2) investigation of the uptake and accumulation of Tc in marine food webs in Norwegian waters. In the present paper we focus on the uptake and accumulation of Tc in benthic species. 

B. N. Bavel, P, A. Bergqvist, D. Broman, K. Lundgren, O. Papakosta, C. Rolff, B. Strandberg, Y. Zebohr, D. Zook, C. Rappe, Levels of PCBs in the aquatic environment of the Gulf of Bothnia benthic species and sediments. Mar. Pollution Bull., 32 (1995), 210-218. 

Number and identity of darter species (benthic species)... 

From 1986 to 1989, the National Study of Chemical Residues in Fish (NSCRF) was conducted by the EPA to assess the concentrations of 60 toxic pollutants (including mercury) in the tissues of benthic and predatory gamefish nationwide (EPA 1992f). Benthic species were analyzed as whole-body samples, while game fish species were analyzed as fillet samples, and all concentrations were reported on a wet weight basis. Mercury was detected at 92% of the 374 sites surveyed nationwide at a mean concentration... 

As documented in the first part of this chapter, distribution patterns of benthic species in the southern Baltic Sea are clearly linked with the salinity gradient (Fig. 17.5). Hydro-graphic conditions, on the contrary, are highly variable (see Chapter 10) showing short term (seasonal or interannual) or long term fluctuations (e.g., saline water inflows). In... 

As to be expected benthic species composition varied considerably in this part of the Baltic (Table 17.1). The most western stations 010 and 012 at the Fehmarn Belt and the Mecklenburg Bight are characterized by the bivalves Abra alba and Arctica islandica and the cumacean Diastylis rathkei, whereas the area around the Darss Sill (stn. 030) were most frequently colonized by the gastropod Hydrobia ulvae, the bivalve Mytilus... 

Schiedek, D., 1997a. Marenzelleria viridis (Verrill 1873) (Polychaeta) a new benthic species within European coastal waters. Some metabolic features. Journal of Experimental Marine Biology and Ecolology, 211, 85-101. 

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