Multiplexed Distributed Acoustic Sensing Offshore Central Oregon

Seismological Research Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 28, 2025

Abstract Distributed acoustic sensing (DAS) on submarine fiber-optic cables is providing new observational insights into solid Earth processes and ocean dynamics. However, the availability of offshore dark fibers for long-term deployment remains limited. Simultaneous telecommunication DAS operating at different wavelengths in same fiber, termed optical multiplexing, offers one solution. In May 2024, we collected a four-day dataset utilizing an L-band interrogator multiplexing Ocean Observatory Initiative’s Regional Cabled Array central Oregon. Our findings show that multiplexed has no impact communications unaffected by network traffic. Moreover, quality data via matches obtained from fiber. With machine-learning event detection workflow, detect 31 T waves S wave regional earthquake, demonstrating feasibility continuous earthquake monitoring using DAS. We also examine ocean-generated seismic noise. note high-frequency noise modulated low-frequency swell hypothesize about its origins. The complete freely available.

Language: Английский

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Humpback-krill relationships are strongest at fine spatial scales in the Northern California Current region

Marine Ecology Progress Series, Journal Year: 2024, Volume and Issue: 729, P. 219 - 232

Published: Jan. 4, 2024

Understanding scale-dependent variability in predator-prey relationships is essential to ecosystem management. The Northern California Current (NCC) an important foraging ground for humpback ( Megaptera novaengliae ) and other rorqual whales, but it also area that presents diverse anthropogenic threats. Clarifying the most meaningful spatial scale analyze between whales krill, a key prey item, understanding function informing research management efforts. To examine spatially explicit krill NCC, we analyzed concurrent whale sightings acoustically detected abundance estimates collected May September 2018 2022. We used generalized additive mixed models predict occurrence at series of ecologically relevant nested scales: 1, 2, 5, 20 km. found relative 5 km had greatest influence on occurrence. Our results suggest may be both energetically profitable optimize efficiency detectable using our traditional methodological approaches (paired observer echosounder surveys). recommend zooplankton data incorporated into future distribution considered applications this region.

Language: Английский

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Exposure of whales to entanglement risk in Dungeness crab fishing gear in Oregon, USA, reveals distinctive spatio-temporal and climatic patterns

Biological Conservation, Journal Year: 2023, Volume and Issue: 281, P. 109989 - 109989

Published: March 13, 2023

Entanglement in fishing gear presents a major threat to marine mammals worldwide and pressing concern for distinct populations of whales off the US West Coast. The lack understanding their fine-scale distribution relation activity limits management efforts, specifically Oregon. Based on year-round predictions rorqual whale densities effort compiled from logbooks, we assess co-occurrence between commercial Dungeness crab over decade (2011–2020) as an indicator exposure entanglement risk. Generalized Additive Models including temporal, climatic, ocean upwelling predictors were used investigate variations exposure. Exposure peaked April, at onset season when predicted occur greater numbers closer shore. remained constant until end nearshore waters <40 fathoms (73 m) decreased past these depths. Across years, was lower during heatwave (2014–2016) more active be less abundant. higher before (2011–2013) after (2017–2020) heatwave, which correspond negative phases Pacific Decadal Oscillation associated with stronger upwelling, indicating productive conditions favorable whales. A recent increase also due slight shift towards deeper waters. These findings illustrate use species models space-use conflicts dynamic ecosystems can guide fisheries reduce risk

Language: Английский

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Biologically Important Areas II for cetaceans within U.S. and adjacent waters - West Coast Region

Frontiers in Marine Science, Journal Year: 2024, Volume and Issue: 11

Published: March 11, 2024

Here we update U.S. West Coast Biologically Important Areas (BIAs) that were published in 2015 using new data and approaches. Additionally, BIAs delineated for two species not the BIAs: fin whales Southern Resident killer (SRKW). While harbor porpoise remained same, substantial changes made other including identifying both larger overall areas (parent BIAs) smaller core (child BIAs). For blue, fin, humpback identified, delineated, scored overlap between distribution relative density from three sources, leveraging strengths weaknesses of these approaches: 1) habitat models based on Southwest Fisheries Science Center (SWFSC) line-transect systematic ship surveys conducted through 2018, 2) satellite tag deployments by research groups, 3) sightings feeding behavior non-systematic effort mostly associated with small-boat photo-identification Cascadia Research Collective. previous solely a more subjective assignment only small boat sightings, here incorporate sources use rigorous, quantitative approach to identify higher integrate types. This resulted larger, better-supported, objective compared effort. Our methods are also consistent delineation regions. SRKWs, parent BIA was modification Critical Habitat boundaries defined National Oceanographic Atmospheric Administration (NOAA) Department Oceans (DFO) Canada; highlighting intensified identified NOAA’s kernel analyses data. Gray whale re-evaluated migratory corridor Eastern North Pacific gray whales, Feeding Group areas, feed regularly Puget Sound.

Language: Английский

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Widespread passive acoustic monitoring reveals spatio-temporal patterns of blue and fin whale song vocalizations in the Northeast Pacific Ocean

Frontiers in Remote Sensing, Journal Year: 2023, Volume and Issue: 4

Published: Feb. 3, 2023

The NOAA-NPS Ocean Noise Reference Station Network (NRS) is a passive acoustic monitoring effort to record the low-frequency (&lt;2 kHz) sound field throughout U.S. Exclusive Economic Zone. Data collection began in 2014 and spans 12 recording locations. To date, NRS datasets have been analyzed understand spatial variation of large-scale levels, however, assessment specific sources an area where these can provide additional insights. seasonal patterns blue whale, Balaenoptera musculus , fin B. physalus production eastern North Pacific Ocean, this study explored data recorded between 2020 from four sites. A call index (CI) was used quantify intensity whale B calls 20 Hz pulses. Diel were then determined context their migratory patterns. Most sites shared similar CI: persistent presence for 4–5 months starting by August ending February with CI maximum October or November. Fin included 5–7 before April December. diel patterning song varied across Gulf Alaska, Olympic Coast, Cordell Bank, Channel Islands (2014–2015) exhibiting tendency towards nighttime detection. However, pattern not observed at (2018–2020). detection distributed evenly day night most months, toward Bank during fall, Alaska Coast spring. Understanding migration whales essential conservation efforts. By using efficient methods, such as CI, it possible process large amounts bioacoustic better behaviors endangered marine species.

Language: Английский

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The variable influence of anthropogenic noise on summer season coastal underwater soundscapes near a port and marine reserve

Marine Pollution Bulletin, Journal Year: 2023, Volume and Issue: 194, P. 115406 - 115406

Published: Aug. 25, 2023

Monitoring soundscapes is essential for assessing environmental conditions soniferous species, yet little known about sound levels and contributors in Oregon coastal regions. From 2017 to 2021, during June-September, two hydrophones were deployed near Newport, sample 10-13,000 Hz underwater sound. One hydrophone was the Port of Newport a high vessel activity area, another 17 km north within protected Marine Reserve. Vessel noise whale vocalizations detected at both sites, but whales recorded on more days Median frequencies related from various types sizes (50 - 4,000 Hz) up 6 dB higher with greater diel variability compared In addition documenting summer season waters, these results exemplify how can differ over short distances depending anthropogenic activity.

Language: Английский

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Krill swarm biomass, energetic density, and species composition drive humpback whale distribution in the Northern California Current

ICES Journal of Marine Science, Journal Year: 2025, Volume and Issue: 82(1)

Published: Jan. 1, 2025

Abstract Prey abundance and quality are dynamic in time space, impacting predator ecology. We examine variation species-specific krill quantity as prey for humpback whales the Northern California Current region, using generalized additive models to assess metrics including biomass energy density derived from an integrated dataset of concurrent active acoustics, net tows, marine mammal observations (2018–2022). Overall, were positively correlated with whale presence, increasing trends modified by seasonal (early versus late foraging season) spatial (continental shelf offshore) (model deviance explained 36.3%–40.8%). Biomass had strong positive effects on suggesting target high-quality swarms that offer more per lunge. Elevated Thysanoessa spinifera near suggests they this species, particularly season when energetically richer than Euphausia pacifica, region’s other abundant species. Environmental change may decrease quality, whales’ ability meet energetic requirements potentially driving changes their distributions exposure anthropogenic threats. Clarifying drivers patch selection can improve species distribution aid managers mitigating risk whales.

Language: Английский

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Ecological drivers of movement for two sympatric marine predators in the California current large marine ecosystem

Movement Ecology, Journal Year: 2025, Volume and Issue: 13(1)

Published: March 18, 2025

An animal's movement reflects behavioral decisions made to address ecological needs; specifically, that will become less directional in regions with high prey availability, indicating foraging behavior. In the marine realm, animal behavior occurs below sea surface and is difficult observe. We used an extensive satellite tagging dataset explore how physical biological habitat characteristics influence blue (Balaenoptera musculus) fin (B. physalus) whale California Current Ecosystem across four known bioregions. fitted models 14 years of tracking data 13 characterize their persistence, higher move persistence values representing more lower movement. Models were evaluated against a range environmental predictors identify significant correlates low (i.e., presumed intensified behavior). then from subset sensor-equipped tags monitored vertical (e.g., dive feeding), addition movement, test relationship between persistence. Low was strongly correlated shallower water depth height for both species, additional effects chlorophyll-a concentration, vorticity nekton biomass whales. Data additionally showed occurred when whales numerous feeding dives. Temporal patterns bioregion occupancy coincided seasonal peaks productivity. Most low-move-persistence movements northern, nearshore late-season peak productivity evenly distributed all bioregions demonstrated indicative increased The drivers similar those previously identified survey-based species distribution models, linking metrics subsurface Occupancy indicate moved exploit spatial variability productivity, especially focusing on highest during late summer fall.

Language: Английский

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Multiscale relationships between humpback whales and forage species hotspots within a large marine ecosystem

Ecological Applications, Journal Year: 2022, Volume and Issue: 33(2)

Published: Dec. 9, 2022

Fluctuations in prey abundance, composition, and distribution can impact predators, when predators fisheries target the same species, become essential to ecosystem-based management. Because of difficulty collecting concomitant predator-prey data at appropriate scales patchy environments, few studies have identified strong linkages between cetaceans prey, especially across large geographic areas. During summer 2018, a line-transect survey for coastal pelagic species was conducted over continental shelf slope British Columbia, Canada, US West Coast, allowing large-scale investigation spatial relationships. We report on case study humpback whales (Megaptera novaeangliae) their primary prey-Pacific herring (Clupea pallasii), northern anchovy (Engraulis mordax), krill-using generalized additive models explore relationships whale abundance 10-km transect segments metrics. Prey metrics included direct measures biomass densities an original hotspot metric. For each upper fifth percentile density (across all segments) were designated hotspots, counts segment evaluated relationship number (species-specific multispecies) within 25, 50, or 100 km. Whale not strongly related densities, whereas using more effective describing variation underscoring that evaluating relevant measurable is critical patchy, dynamic marine environments. Our analysis highlighted differences availability three distinct population (DPSs) as defined under Endangered Species Act, including threatened endangered DPSs forage California Current Large Marine Ecosystem. These provide insights into which may be targeting different regions multiple and, consequently, how climatic variability anthropogenic risks differentially these assemblages. By identifying scale-appropriate hotspots co-occur with aggregations, targeted, consistent sampling estimations potential consumption rates by whales, findings help inform conservation management framework.

Language: Английский

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Widespread parasite infections in living resident killer whales in the Northeast Pacific Ocean

Published: July 16, 2024

ABSTRACT Multiple populations of resident ecotype killer whales ( Orcinus orca ater ) inhabit the Northeast Pacific, but southern whale (SRKW) population is most at-risk. SRKWs were listed as endangered in United States 2005 and have since shown little sign recovery. Several factors been identified key threats to this population, previously published studies suggest may be energetically stressed. Underlying health risks, such parasitism, contributing population’s failure recover, known about parasite infections living individuals from natural populations. To assess prevalence internal Northeastern Pacific whales, we examined scat SRKW (n = 25) compared two conspecific that are not decline: northern (NRKW, n 2) Alaska (SARKW, 7), one offshore (OKW, 1). We analyzed 35 fecal samples collected 27 wild using both microscopic identification eggs genetic detection parasites through DNA metabarcoding. used body condition indices derived concurrent aerial photogrammetry evaluate whether infection status was associated with individual condition. found sampled (94%) positive for Anisakis spp. – a parasitic nematode intestines cetaceans. These detected across populations, correlated condition, based on limited paired data. results widespread among Pacific. The detections here emphasizes need further work understand potential impacts synergistic effects other environmental stressors.

Language: Английский

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