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B. Kynard

Publications and source records attributed to B. Kynard.

27 records · Page 2Linked to original sources
USGS1997

Video evaluation of passage efficiency of American shad and sea lamprey in a modified ice harbor fishway

Movement and behavior of adult American shad Alosa sapidissima and sea lamprey Petromyzon marinus were monitored by closed-circuit video at several locations within a modified Ice Harbor fishway. American shad ascended and descended the fishway exclusively by surface weirs, while sea lampreys used both surface weirs and submerged orifices. Upstream movement of American shad during the day was higher than at night at both lower and middle fishway observation sites. Peak downstream movement of American shad at both locations was associated with decreasing light levels in the evening. Sea lampreys moved primarily at night at the lower and middle fishway sites. Mean daily passage efficiency was low (1% for American shad, −2% for sea lamprey) at the lower fishway surface weir, but passage efficiency at the middle fishway surface weir was moderate (70% for American shad, 35% for sea lamprey) . High water velocity, air entrainment, and turbulence of the modified Ice Harbor fishway design appeared to inhibit American shad and sea lamprey passage by disrupting upstream migratory motivation and visual and rheotactic orientation.

North American Journal of Fisheries Management↗
USGS1996

Spawning of the shortnose sturgeon the Merrimack River, Massachusetts

We tracked 10 ultrasonically tagged shortnose sturgeons Acipenser brevirostrurn during spring in the Merrimack River to investigate spawning. Seven fish in 1989 and six fish in 1990 were tracked intensively to identify the timing and location of spawning and to characterize spawning habitat. In mid‐April 1989 and 1990, fish moved upstream to just below head of tide, concentrating in a 2‐km reach at river kilometers 30–32 (measured from the mouth) at Haverhill, Massachusetts. The estimated spawning time was a 5‐d period (26–30 April) in 1989 and an 8‐d period (22–29 April) in 1990. Spawning sites covered about 10.5 ha in 1989 and 13.5 ha in 1990. Fish spawned as river temperature increased from 9.6 to 14.0°C and river discharge decreased from 390 to 240 m 3 /s. Physical characteristics of spawning sites were boulder–rubble substrate, water depth of 1.8–5.5 m, and bottom water velocity of 0.3–0.7 m/s. We captured no ovulating females but verified successful spawning in 1990 by capturing two live embryos. Gill‐net captures and telemetry during spring showed that some males moved to the spawning area annually. The low abundance estimates of spawning fish (9 in 1989 and 16 in 1990) indicate that the shortnose sturgeon population in the Merrimack River is the smallest yet identified and is likely vulnerable to extirpation.

Massachusetts↗
USGS1993

Annual movements of shortnose and Atlantic sturgeons the Merrimack River, Massachusetts

We used biotelemetry to study the movements of 23 adult shortnose sturgeons Acipenser brevirostrum and 23 subadult Atlantic sturgeons Acipenser oxyrhynchus oxyrhynchus in the lower 46 km of the Merrimack River between 1987 and 1990. Shortnose sturgeons used two freshwater reaches and one saline reach annually. Sexually mature fish began moving upriver from freshwater wintering areas to a spawning site in April, when increasing river temperature reached about 7°C and decreasing river discharge reached about 570 m 3 /s. Following spawning in late April–early May, fish moved downriver either to a freshwater reach where they remained all year or farther downriver to a saline reach where they remained for up to 6 weeks. After fish used the saline reach, they returned upriver to fresh water. Atlantic sturgeons entered the river from coastal waters by mid–late May, when increasing river temperatures reached 14.8–19.0°C and decreasing river discharge reached 303–675 m 3 /s, occupying a saline reach with 0.0–27.5‰ salinity. After using the same saline reach visited briefly in spring by shortnose sturgeons, Atlantic sturgeons emigrated from the river by October when maximum river temperatures were 13.0–18.4°C. We observed no tagged Atlantic sturgeons in the river in successive years. Except for use of the saline reach during spring, the two species were spatially separate.

Massachusetts↗
USGS1993

Evaluation of a bypass system for spent American shad at Holyoke Dam, Massachusetts

A bypass system for postspawned American shad Alosa sapidissima began operation in 1980 on the Connecticut River canal system at Holyoke Dam. The purpose of the bypass was to enable downstream migrants that enter the canal to exit and avoid death due to delay or passage through hydroelectric turbines at water use facilities. The bypass system had the following elements: (1) an underwater AC electrical or acoustic barrier to prevent American shad from leaving the bypass area, (2) an underwater DC electrical field to immobilize fish for collection, and (3) a collection box with transfer pipe to carry fish to the river below the dam. During studies of the bypass system from 1979 to 1983, we found that the fish barriers were ineffective, the collection system was partially effective for American shad but not for anadromous species that passed through trashracks, and American shad could be immobilized and transported at high velocity through a pipe and have only low mortality (4–9%). Radio‐tagged American shad, unwilling to pass through trashracks at water exits on the canal, behaved like trapped fish and were delayed an average of two or more days before dying or exiting the canal. An estimated 10 of 47 (21%) of the radio‐tagged fish were passed. In 1980, when the greatest number of American shad were passed, an estimated 142,000 (37% ofthe fish lifted at the dam) survived spawning and used the bypass. After several years of operation, it was evident that, even with major improvements, the bypass could not pass the available American shad, and it was not useful for protecting other anadromous migrants that did not avoid trashracks.

Massachusetts↗