Advances in experimental medicine and biology, 2016
The question we addressed in this study is whether oyster toadfish respond to vessel disturbances... more The question we addressed in this study is whether oyster toadfish respond to vessel disturbances by calling less when vessels with lower frequency spectra are present in a sound recording and afterward. Long-term data recorders were deployed at the Neuse (high vessel-noise site) and Pamlico (low vessel-noise site) Rivers. There were many fewer toadfish detections at the high vessel-noise site than the low-noise station. Calling rates were lower in the high-boat traffic area, suggesting that toadfish cannot call over loud vessel noise, reducing the overall calling rate, and may have to call more often when vessels are not present.
The Journal of the Acoustical Society of America, 2012
ABSTRACT Passive acoustic monitoring can be a useful tool to include on Ocean Observing Systems. ... more ABSTRACT Passive acoustic monitoring can be a useful tool to include on Ocean Observing Systems. As an example, we describe the monitoring the acoustic environment in the coastal waters of North Carolina (USA) using an instrumented platform. The ECU Itpod (instrumented tripod) has been deployed in several locations in Pamlico Sound and river estuaries since 2006 to study fishes in the Family Sciaenidae (drums and croakers). We will present data recorded with hydrophones deployed on the Itpod with remote data loggers, acoustic Doppler current profilers, turbidity meters and water quality instruments. We have used passive acoustic recordings to study the correlations of fish sounds and environmental parameters (temperature, salinity, turbidity, dissolved oxygen, wave action, river discharge, tropical storms). The long-term data suggest that spring temperature increases are associated with increased activity of acoustically mediated courtship and spawning behavior of sciaenid fishes; these sounds decline in the fall as water temperature declines. In addition, we have observed acoustic interactions between marine mammal predators and their fish prey and the effects of noise from tugs and small boats on fish sound production. Itpods must be recovered periodically to recover data and replenish batteries; solar-powered platforms and automated fish detection algorithms are under development.
The Journal of the Acoustical Society of America, 2012
ABSTRACT Passive acoustic monitoring is a useful tool for studying soniferous fishes in shallow w... more ABSTRACT Passive acoustic monitoring is a useful tool for studying soniferous fishes in shallow water estuaries. We have used a variety of techniques for monitoring the acoustic environment in the coastal waters of North Carolina (USA) to study fishes in the Family Sciaenidae (drums and croakers), which produce sounds with frequencies below 1000 Hz. We will present data recorded with hydrophones deployed from a small boat, a hydrophone array towed behind a boat, and remote data loggers. We have used passive acoustic recordings to study the distributions (large- and small-scale) and seasonality of acoustically active courtship and spawning behavior, acoustic interactions between predators and prey, the effects of noise from tugs and small boats on fish sound production, and relationships between fish sound production and environmental parameters such as temperature and salinity. One limitation on shallow-water acoustic monitoring is the sound propagation cutoff frequency, which depends on the water depth. All frequency components below the cutoff frequency decay exponentially with propagation distance. This limit on shallow-water sound propagation must be considered when selecting locations for acoustic monitoring and comparing recordings made in waters of different depths. We will explore the implications on acoustic monitoring due to the cutoff frequency.
North American Journal of Fisheries Management, 2009
... The effects of icing and freezing on the length and weight of groundfish species. Internation... more ... The effects of icing and freezing on the length and weight of groundfish species. International Commission for the Northwest Atlantic Fisheries Research Document , 69/2: 7993. View all references). Desiccation and related weight loss were also noted when fish fillets were ...
North American Journal of Fisheries Management, Oct 1, 2009
... The effects of icing and freezing on the length and weight of groundfish species. Internation... more ... The effects of icing and freezing on the length and weight of groundfish species. International Commission for the Northwest Atlantic Fisheries Research Document , 69/2: 7993. View all references). Desiccation and related weight loss were also noted when fish fillets were ...
Advances in experimental medicine and biology, 2016
The question we addressed in this study is whether oyster toadfish respond to vessel disturbances... more The question we addressed in this study is whether oyster toadfish respond to vessel disturbances by calling less when vessels with lower frequency spectra are present in a sound recording and afterward. Long-term data recorders were deployed at the Neuse (high vessel-noise site) and Pamlico (low vessel-noise site) Rivers. There were many fewer toadfish detections at the high vessel-noise site than the low-noise station. Calling rates were lower in the high-boat traffic area, suggesting that toadfish cannot call over loud vessel noise, reducing the overall calling rate, and may have to call more often when vessels are not present.
The Journal of the Acoustical Society of America, 2012
ABSTRACT Passive acoustic monitoring can be a useful tool to include on Ocean Observing Systems. ... more ABSTRACT Passive acoustic monitoring can be a useful tool to include on Ocean Observing Systems. As an example, we describe the monitoring the acoustic environment in the coastal waters of North Carolina (USA) using an instrumented platform. The ECU Itpod (instrumented tripod) has been deployed in several locations in Pamlico Sound and river estuaries since 2006 to study fishes in the Family Sciaenidae (drums and croakers). We will present data recorded with hydrophones deployed on the Itpod with remote data loggers, acoustic Doppler current profilers, turbidity meters and water quality instruments. We have used passive acoustic recordings to study the correlations of fish sounds and environmental parameters (temperature, salinity, turbidity, dissolved oxygen, wave action, river discharge, tropical storms). The long-term data suggest that spring temperature increases are associated with increased activity of acoustically mediated courtship and spawning behavior of sciaenid fishes; these sounds decline in the fall as water temperature declines. In addition, we have observed acoustic interactions between marine mammal predators and their fish prey and the effects of noise from tugs and small boats on fish sound production. Itpods must be recovered periodically to recover data and replenish batteries; solar-powered platforms and automated fish detection algorithms are under development.
The Journal of the Acoustical Society of America, 2012
ABSTRACT Passive acoustic monitoring is a useful tool for studying soniferous fishes in shallow w... more ABSTRACT Passive acoustic monitoring is a useful tool for studying soniferous fishes in shallow water estuaries. We have used a variety of techniques for monitoring the acoustic environment in the coastal waters of North Carolina (USA) to study fishes in the Family Sciaenidae (drums and croakers), which produce sounds with frequencies below 1000 Hz. We will present data recorded with hydrophones deployed from a small boat, a hydrophone array towed behind a boat, and remote data loggers. We have used passive acoustic recordings to study the distributions (large- and small-scale) and seasonality of acoustically active courtship and spawning behavior, acoustic interactions between predators and prey, the effects of noise from tugs and small boats on fish sound production, and relationships between fish sound production and environmental parameters such as temperature and salinity. One limitation on shallow-water acoustic monitoring is the sound propagation cutoff frequency, which depends on the water depth. All frequency components below the cutoff frequency decay exponentially with propagation distance. This limit on shallow-water sound propagation must be considered when selecting locations for acoustic monitoring and comparing recordings made in waters of different depths. We will explore the implications on acoustic monitoring due to the cutoff frequency.
North American Journal of Fisheries Management, 2009
... The effects of icing and freezing on the length and weight of groundfish species. Internation... more ... The effects of icing and freezing on the length and weight of groundfish species. International Commission for the Northwest Atlantic Fisheries Research Document , 69/2: 7993. View all references). Desiccation and related weight loss were also noted when fish fillets were ...
North American Journal of Fisheries Management, Oct 1, 2009
... The effects of icing and freezing on the length and weight of groundfish species. Internation... more ... The effects of icing and freezing on the length and weight of groundfish species. International Commission for the Northwest Atlantic Fisheries Research Document , 69/2: 7993. View all references). Desiccation and related weight loss were also noted when fish fillets were ...
Uploads
Papers by Cecilia S Krahforst