Population Maintenance of the Scyphozoan Cyanea sp. Settled Planulae and the Distribution of Medusae in the Niantic River, Connecticut, USA

Scyphozoan jellyfish are seasonally conspicuous in coastal waters, but relatively little is known about the factors that control their distribution and population dynamics.Cyanea sp is a seasonally abundant medusa in the Niantic River, Connecticut, U.S. and appears to maintain a population entirely within the estuary. To better understand the factors controlling their occurrence, we examined the temporal and spatial distribution of settled scyphistomae in relation to that of the medusae. Planula settlement patterns mirrored the presence of mature female medusae. The planulae settled primarily near the bottom. After settlement, planulacysts and polyps on the settlement plates were out competed by large barnacle and ascidian larvae, resulting in a sharp decline in cyst and polyp abundance. This stage-specific mortality may represent a population bottleneck in the life cycle of scyphozoans

Comment letters to the National Commission on Commission on Fraudulent Financial Reporting, 1987 (Treadway Commission) Vol. 1

https://egrove.olemiss.edu/aicpa_sop/1661/thumbnail.jp

Monitoring the marine environment of Long Island Sound at Millstone Nuclear Power Station, Waterford, Connecticut : annual report ...

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Downstream passage of radiotagged Atlantic salmon (Salmo salar) smolts at the Holyoke Project, Holyoke, Massacusetts, 1995

Downstream fish passage facilities at the Holyoke Project were modified to enhance the passage of Atlantic salmon (Salmo salar) smolts. A pier extension was installed adjacent to the Holyoke Dam bascule gate, the opening of an experimental weir inserted in the bascule gate was moved closer to the Hadley Falls Station intakes, and above-water lighting was added. An intake rack overlay was in place at both Hadley Falls Station units during the first half of this evaluation; the Unit 2 overlay was removed during the second half. Radiotagged, hatchery-reared Atlantic salmon smolts were released upstream of the Project and downstream passage routes were monitored. All releases were conducted after flashboards had been installed on the crest of the dam, closing that passage route. Overall, 63% of the radiotagged smolts that approached Hadley Falls Station passed over the bascule gate weir and 37% passed through the turbines. These results were comparable to results obtained in a 1992 evaluation, when a floating guide wall was present upstream of the intakes. Two-thirds of the radiotagged smolts that passed through the turbines at Hadley Falls Station did so through Unit 1. Removal of the Unit 2 intake rack overlay did not affect the proportion of radiotagged smolts passing through the turbines. Combining data from 1992 and 1995, a statistically significant but weak negative relationship between flow through the station and the proportion of radiotagged smolts passing over the bascule gate/weir was found. The louver/bypass system in the Holyoky Canal passed 91% of the radiotagged smolts entering the canal back to the Hadley Falls Station tailrace. Above-water lighting installed upstream of the canal gatehouse appeared to have raised the proportion of radiotagged smolts entering the canal. When the results of passage through the bascule gate weir and the louver/bypass system were combined, 74% of the radiotagged smolts passed through downstream passage facilities. Smolts passing through the louver/bypass system or through the turbines arrived at a location downstream of the dam more quickly than smolts that had passed through the bascule gate weir

Response of Adult American Shad to Floating Louvers in Holyoke Canal

None. Summary: As part of a larger effort to identify alternative methods to bypass outmigrating anadromous fishes at Hadley Falls Project, a 14-day study was conducted during June, 1990 to evaluate the response of post-spawning adult American shad to a floating louver array 522 feet long angled at 15 degrees to the flow in the Holyoke Canal. This study partially completes the evaluation of various louver arrays under different flows. In addition, in preparation for studies with juvenile clupeids, a pilot study was conducted to test the ability of hydroacoustics to detect small fish