Geology topics

Ann B. Grote

Publications and source records attributed to Ann B. Grote.

4 recordsLinked to original sources

USGS2024

Pacific Lamprey responses to stressors: Dewatering and electrofishing

The Pacific Lamprey Conservation Initiative (PLCI) is a collaboration of Tribes, Federal, and State agencies working together to protect and restore Pacific Lamprey ( Entosphenus tridentatus ) and other native lampreys (i.e., Lampetra spp.) in Alaska, Washington, Oregon, California, and Idaho. The U.S. Fish and Wildlife Service hosts and facilitates the PLCI, and the Columbia River Tribes play a large role in setting conservation goals and defining research needs. The PLCI annually solicits proposals for research and restoration activities, which are reviewed and ranked in collaboration with the Bonneville Power Administration (BPA), who annually provides funding to support PLCI priority proposals. This report summarizes two research projects selected through PLCI, and funded under one BPA contract, in support of Pacific Lamprey conservation. The two projects were not topically related apart from a common theme of potential stressors to lampreys and are being reported together because they were combined under one BPA agreement for contracting.

Report↗

USGS2023

Synthesis of larval lamprey responses to dewatering: State of the science, critical uncertainties, and management implications

Objective Dewatering of fine sediments in rivers and streams can kill many thousands of larval lampreys (order Petromyzontiformes) that are burrowed in these habitats. The larval life stage for lampreys lasts 3–10 years, and because larvae often aggregate in large numbers, negative impacts from dewatering could potentially deplete local populations and affect multiple year-classes. Larval lampreys have not traditionally been considered during instream projects, but recent efforts to increase awareness of lamprey habitats have resulted in guidance on dewatering approaches to limit impacts to lampreys. Salvage efforts to rescue and relocate lampreys aim to mitigate losses, but a lack of understanding of lamprey responses limits the optimization of dewatering and salvage procedures. Methods We summarize the state of the science for nine factors that influence larval lamprey ( Entosphenus and Lampetra spp.) responses to dewatering, including burrowing depth, the prevalence and timing of emergence, movements, survival, shoreline slope, dewatering rate, light, and lamprey size. Result Research suggests that (1) shoreline slope influences movement capability, (2) hot and sunny conditions increase the risk of mortality, (3) salvage activities cause minimal direct mortality, and (4) smaller larvae are especially vulnerable to negative impacts from dewatering because they are more likely to emerge and are less capable of movement. Critical uncertainties associated with dewatering include cues that drive emergence, the influence of sediment composition and stratigraphy, vertical distribution of larvae in natural settings, use of the hyporheic zone, the scale of predation losses, and the effectiveness and impacts of salvage activities. Conclusion Balancing investments in salvage operations and lamprey exclusion efforts (e.g., screening) and developing field survey approaches to evaluate lamprey use of the hyporheic zone are identified management implications and research needs. Addressing the critical uncertainties discussed here and providing updated, science-based guidance on dewatering and salvage practices are suggested management actions to support lamprey conservation.

North American Journal of Fisheries Management↗

USGS2014

Movements and demography of spawning American Shad in the Penobscot River, Maine, prior to dam removal

We conducted a baseline study to better understand the migratory movements and age and spawning histories of American Shad Alosa sapidissima in the Penobscot River, Maine. The Penobscot River is currently undergoing a major dam removal project that is focused on restoring migratory connectivity and recovering diadromous fish populations including American Shad. This study addresses key data gaps for a previously unstudied native population of shad prior to restoration. A combination of radio- ( n = 70) and acoustic telemetry ( n = 14) was used to investigate the movements of migratory adult fish in 2010 and 2011. Scale-based analyses were used to assess spawner age and iteroparity. Radiotelemetry results indicated that few tagged fish (5–8%) approached the head-of-tide dam. Tagged fish exhibited three general patterns of movement in the accessible freshwater river habitat: use of the upper river reach, the lower river reach, or both. Mean freshwater residence time ranged from 9.1 to 14.0 d. Congregating fish were observed at two sites in the upper river reach and spawning activity was observed. Freshwater survival and survival to the estuary were at least 71%. This observed high survival was consistent with the estimated age and spawning histories of tracked fish, which indicated that 75–95% of the sampled fish were repeat spawners. Estimated age of adult migrants ranged from age 4 to age 9. Postspawning acoustic-tagged American Shad exhibited a series of prolonged upstream and downstream reversals upon entering the lower estuary. These movements have been previously unreported, and suggest that estuarine residency after spawning is important to osmoregulatory acclimatization for re-entry into salt water and the resumption of postspawning feeding activity.

Transactions of the American Fisheries Society↗

USGS2014

Multibeam sonar (DIDSON) assessment of American shad ( Alosa sapidissima ) approaching a hydroelectric dam

We investigated the fish community approaching the Veazie Dam on the Penobscot River, Maine, prior to implementation of a major dam removal and river restoration project. Multibeam sonar (dual-frequency identification sonar, DIDSON) surveys were conducted continuously at the fishway entrance from May to July in 2011. A 5% subsample of DIDSON data contained 43 793 fish targets, the majority of which were of Excellent (15.7%) or Good (73.01%) observation quality. Excellent quality DIDSON targets ( n = 6876) were apportioned by species using a Bayesian mixture model based on four known fork length distributions (river herring (alewife, Alosa psuedoharengus , and blueback herring, Alosa aestivalis ), American shad, Alosa sapidissima ) and two size classes (one sea-winter and multi-sea-winter) of Atlantic salmon ( Salmo salar ). 76.2% of targets were assigned to the American shad distribution; Atlantic salmon accounted for 15.64%, and river herring 8.16% of observed targets. Shad-sized (99.0%) and salmon-sized (99.3%) targets approached the fishway almost exclusively during the day, whereas river herring-sized targets were observed both during the day (51.1%) and at night (48.9%). This approach demonstrates how multibeam sonar imaging can be used to evaluate community composition and species-specific movement patterns in systems where there is little overlap in the length distributions of target species.

Canadian Journal of Fisheries and Aquatic Sciences↗