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At least 253 records · Page 14Linked to original sources

Review of Grasse River Lake Sturgeon habitat use and possible post-Superfund remediation agency actions

The Grass River (hereafter Grasse River) historically served as a major source of fisheries production for the Saint Lawrence River (hereafter St. Lawrence River) basin, providing critical spawning habitat and support for other life history stages of numerous species including the culturally and ecologically significant Lake Sturgeon ( Acipenser fulvescens ). Decades of environmental degradation resulted in designation of the lower Grasse River as the Grasse River Superfund site and part of the St. Lawrence River Area of Concern (AOC) at Massena/Akwesasne. The primary problems were severe contamination of sediments and fish, with numerous environmental beneficial use impairments (BUIs) including losses and degradation of habitat and diminished animal populations that limited fisheries production and reduced ecosystem services provided by the Grasse River. Efforts to restore the lower Grasse River within the AOC were initiated in 2019 to remove or isolate contaminants, repair damaged habitats, and rebuild fish and wildlife populations. The purpose of this report is to 1) summarize the history and contemporary status of environmental conditions and fisheries in the Grasse River, with an emphasis on Lake Sturgeon; 2) summarize remediation and restoration activities and how they may affect fisheries habitat and populations; and 3) discuss potential options for continued habitat remediation in addition to currently proposed restoration actions.

New York

Origin and history of the Charleston Bump - Geological formations, currents, bottom conditions, and their relationship to wreckfish habitats on the Blake Plateau

The Charleston Bump is a structural and topographic high on the northern Blake Plateau that overlies a seaward offset of the edge of continental crust. The feature causes the bottom to shoal and deflects the Gulf Stream offshore, causing an intensification of bottom currents. The area has been swept by strong currents since late Cretaceous time, but the strongest currents have occurred in the Neogene (last ???25 million years). Nondepositional conditions prevail at present, but erosion of the bottom is checked where the bottom is armored by a hard surficial layer of phosphorite pavement. The phosphorite pavements were formed by re-cementation of eroded residues of phosphorite-rich sediments of early-Neogene age. In some places there are multiple pavements separated by poorly lithified sediments. Submersible observations indicate that the south, or current-facing flank of the Charleston Bump has several deep (>100 m) scour depressions, the southern flanks of which form cliffs characterized by ledges and overhangs. In other areas discrete layers of older Paleogene rocks have been partly eroded away, leaving cliff-like steps of 5 m or more relief. Conglomeratic phosphorite pavement layers up to 1 m thick armor most of the bottom. Where breached by scour, these pavements form both low-relief ledges and rock piles. These features form a reef-like environment of caves and overhangs utilized by wreckfish Polyprion americanus and barrelfish Hyperoglyphe perciformis as shelter from the current and as staging areas to prey on passing schools of squid. Wreckfish and other large fish were often localized in rugged bottom habitat, including caves and other shelter areas. We observed wreckfish darting from shelters to feed on passing schools of squid. Present and past observations, are consistent with the concept that impingement of the Gulf Stream at the Charleston Bump compresses midwater fauna from much thicker water layers, providing food for a flourishing big-fish fauna. During our dives we noted currents often exceeding 1 knot, and ranging to 2.4 knots. Evidence of fossil, manganese-iron-encrusted megaripples suggest even greater current regimes in the past. Investigation of the site of an earlier report of possible freshwater discharge failed to find any evidence of a closed sinkhole or freshwater discharge. Rather, we concluded that the apparent loss of buoyancy experienced by the submarine was probably caused by downward-directed eddy currents generated by currents sweeping across the pavement/void interface of a more than 100-m high cliff 3 km south of the reported location.

American Fisheries Society Symposium

Habitat Suitability Index Models: Spotted seatrout

The estuarine spotted seatrout, a primarily estuarine species, is one of the most important sport and commercial fishes in coastal Gulf of Mexico waters (Arnold et a1. 1976). Spotted seatrout rank second by weight in catches by U.S. saltwater sport fishermen (National Marine Fisheries Services 1981) .

FWS/OBS