Stellwagen Bank Research Articles

Diel changes in humpback whale Megaptera novaeangliae feeding behavior in response to sand lance Ammodytes spp. behavior and distribution

Humpback whales Megaptera novaeangliae have adopted unique feeding strategies to take advantage of behavioral changes in their prey. However, logistical constraints have largely lim- ited ecological analyses of these interactions. Our objectives were to (1) link humpback whale feed- ing behaviors to concurrent measurements of prey using scientific echo-sounders, and (2) quantify how sand lance behavior influences the feeding behaviors and foraging ecology of humpback whales. To measure, in fine detail, the 3-dimensional orientation and movement patterns of hump- back whales underwater, we used a multi-sensor tag attached via suction cups (DTAG). We tested the specific hypothesis that the diel movement patterns of sand lance between bottom substrate and the water column correlates to changes between surface and bottom feeding strategies of humpback whales on Stellwagen Bank, MA. We collected over 96 h of both day- and nighttime data from 15 whales in 2006, and recorded 393 surface and 230 bottom feeding events. Individual whales exhibit both surface and bottom feeding behaviors, switching from one to the other in relation to changing light and prey conditions. Surface feeding behaviors were individually variable in their constitution but ubiquitously biased towards daylight hours, when prey was most abundant in the upper portion of the water column. Bottom feeding behavior occurred largely at night, coincident with when sand lance descend to seek refuge in the substrate. Our data provide novel insights into the behavioral ecology of humpback whales and their prey, indicating significant diel patterns in for- aging behaviors concurrent with changes in prey behavior.

Erratum to: Characterizing the Relative Contributions of Large Vessels to Total Ocean Noise Fields: A Case Study Using the Gerry E. Studds Stellwagen Bank National Marine Sanctuary

Erratum to: Characterizing the Relative Contributions of Large Vessels to Total Ocean Noise Fields: A Case Study Using the Gerry E. Studds Stellwagen Bank National Marine Sanctuary

Analysis of most prominent signal features of humpback whale (Megaptera Novaeangliae) vocalizations towards the goal of autonomous acoustic classification.

Humpback whale vocalizations were recorded using hydrophones on glider systems off Alaska in January 2000, in Hawaii in February 2008, and in the Stellwagen Bank National Marine Sanctuary in October 2007 and July 2008. The vocalizations have been grouped into five call types based on the most prominent signal features. Only five call types are used because autonomous species classification relies on the most consistent and repeatable signal features rather than the full diverse range of humpback vocalizations. The five call types are upsweep (increasing frequency over time), downsweep (decreasing frequency over time), flute (increasing and decreasing frequency over time), tone (little or no change in frequency over time), and groan (commonly a social or feeding-related vocalization, frequently characterized by unstructured broadband sound). We present detailed statistical analyses of these call types including bandwidth, minimum and maximum frequency, duration, and slope. A comparative analysis across data sets shows the relative frequency of occurrence of each vocalization type and indicates the degree of temporal and geographic variation of Humpback vocalizations.

Characterizing the relative contributions of large vessels to total ocean noise fields: a case study using the Gerry E. Studds Stellwagen Bank National Marine Sanctuary

Understanding and mitigating the effects of underwater noise on marine species requires substantial information regarding acoustic contributions from shipping. In 2006, we used the U.S. Coast Guard's Automatic Identification System (AIS) to describe patterns of large commercial ship traffic within a U.S. National Marine Sanctuary. AIS data were combined with low-frequency acoustic data from an array of nine-ten autonomous recording units deployed throughout 2006. Analysis of received sound levels (10-1000 Hz, root-mean squared decibels re 1 μPascal ± standard error) averaged 119.5 ± 0.3 at high traffic locations. High traffic locations experienced double the acoustic power of less trafficked locations for the majority of the time period analyzed. Average source level estimates (71-141 Hz, root-mean squared decibels re 1 μPascal ± standard error) for individual vessels ranged from 158 ± 2 (research vessel) to 186 ± 2 (oil tanker). Tankers were estimated to contribute two times more acoustic power to the region annually than cargo ships, and over one hundred times more than research vessels. Our results indicate that noise produced by large commercial traffic was at levels and within frequencies that warrant concern among managers regarding the ability of endangered whales to maintain acoustic contact within greater sanctuary waters.

Cover Caption

Conservation BiologyVolume 22, Issue 2 p. i-i Cover Caption First published: 08 April 2008 https://doi.org/10.1111/j.1523-1739.2008.00935.xAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Abstract Cover: Each year, over 1 million people journey to the Stellwagen Bank National Marine Sanctuary for commercial whale-watching trips that view endangered whales, such as this breaching humpback. In an attempt to safeguard whales while providing viewers with an educational experience a voluntary conservation approach is being used in the area.The National Oceanic and Atmospheric Administration wrestles with the value of such voluntary approaches versus regulations as a management tool. See pages 450–457. Photo by Oktay Kaya. Volume22, Issue2April 2008Pages i-i RelatedInformation

Stellwagen Bank

Stellwagen Bank Lydia Peelle (bio) I've been down in the graveyard, most days this winter, thinking about our forefathers, our foremothers, the future and what might meet us there. It is February in Provincetown, on the outer reach of the Cape Cod peninsula. The wind whips in with the accumulated energy of three thousand unbroken miles across the Atlantic, the sun slips over the horizon early in the evenings—there's time to think about things. I read names and inscriptions, figure ages from dates, search for some sort of story, some kind of clue. Something more about the lives these stones are meant to memorialize—something more about that dash between the dates. Something of the hope and grief of these generations, the mothers and fathers who worked themselves to the ground and grave to carve out lives for their daughters and sons. Something of the people dedicated to the wealth and the liberty of a small plot of land by the sea—here on this spit, this curling arm of sand—here on the edge, the tip, the end, the very end, of this continent. For years, resourceful men and women scavenged what washed ashore of shipwrecks all along the outer arm of the Cape. These are dangerous, shoal-riddled waters, and there was never any shortage of plunder. In 1840, after the Franklin wrecked in shallow waters just off Ballston Beach, people came down to the dunes and watched for days as lifeboats tried and failed to save the doomed passengers and crew. An old man who lived out in Wellfleet opened a chest that washed up and found several unmarked packets of seeds. Seeing opportunity, he took them home and planted them in his garden. Months later, when Henry Thoreau happened to pass through, the old man and his wife had been living all summer off of the foreign plants that grew from those seeds. Henry spent the night, and as he was leaving the next day, the old man took him gently by the arm. You're a man of science. You've seen some things. Come on out to my garden and tell me what we've been eating. So Henry went out to the garden with him and gave a name to each plant in turn. The mystery was revealed as if a cloth had been pulled off the garden plot, as in a magic trick. Broccoli. Cabbage. Parsley. On the edge of the sea, we are all of us scavengers. Crabs pick at bones. Gulls squawk and drop urchin shells on the graveyard road to shatter. What can we salvage, drag home over the dunes? I want to plant the [End Page 66] washed-up seeds. See what comes up. Harvest the stories of the dead. What can they tell me of the life that lies ahead, a future that seems to grow more uncertain by the hour? On a tomb set in the side of a hill beside the graveyard road, three names share one granite plaque: Captain James Small and his two sons, James and Joshua, Lost at Sea, September, 1846. There is one other plaque set in the side of the tomb: Betsey, mother and wife. Who died seven months later, according to the inscription, broken hearted at her loss. But how did her heart break, I need to know. Did it shatter? Did it crack? Did it tear along the seams? Did it rust out slowly, in the salt air, or did Betsey, overcome by loss, walk out into the ocean one morning, out towards her sons and husband, and simply let her heart fill up with seawater? In the deep ocean, there falls a snow: tiny bits of bone and teeth and scale, the remains of plants and animals always sifting, always swirling through the strata. We here on land have not much more than this—fragments, slivers, chips of bone—but it is all we have to work with. I am beginning to think that it all may come down to something about grief. Dorothy Bradford, I think of you. From atop the Small family's hill in the graveyard, one can look out over...

Anthropogenic Noise as a Stressor in Animals: A Multidisciplinary Perspective

This paper could not have been written without the financial and organizational support from Dieter Paulmann and Jo Hastie respectively. Thanks are also due to 2 anonymous reviewers, whose comments on an earlier version of the manuscript greatly improved the paper. The views expressed in this paper are those of the authors alone and do not represent those of Stellwagen Bank National Marine Sanctuary, the U.S. National Marine Sanctuary Program, Southwest Fisheries Science Center, the U.S. National Marine Fisheries Service, NOAA and/or any other institution or agency. Correspondence concerning this article should be addressed to Andrew Wright, Leviathan Sciences, U.S.A. (marinebrit@gmail.com). Consequences of extreme noise exposure are obvious and usually taken into some consideration in the management of many human activities that affect either human or animal populations. However, the more subtle effects such as masking, annoyance and changes in behavior are often overlooked, especially in animals, because these subtleties can be very difficult to detect. To better understand the possible consequences of exposure to noise, this review draws from the available information on human and animal physiology and psychology, and addresses the importance of context (including physiological and psychological state resulting from any previous stressor exposure) in assessing the true meaning of behavioral responses. The current consensus is that the physiological responses to stressors of various natures are fairly stereotyped across the range of species studied. It is thus expected that exposure to noise can also lead to a physiological stress response in other species either directly or indirectly through annoyance, a secondary stressor. In fact many consequences of exposure to noise can result in a cascade of secondary stressors such as increasing the ambiguity in received signals or causing animals to leave a resourceful area, all with potential negative if not disastrous consequences. The context in which stressors are presented was found to be important not only in affecting behavioral responses, but also in affecting the physiological and psychological responses. Young animals may be particularly sensitive to stressors for a number of reasons including the sensitivity of their still-developing brains. Additionally, short exposure to stressors may result in long-term consequences. Furthermore, physiological acclimation to noise exposure cannot be determined from apparent behavioral reactions alone due to contextual influence, and negative impacts may persist or increase as a consequence of such behavioral changes. Despite the lack of information available to managers, uncertainty analysis and modeling tools can be coupled with adaptive management strategies to support decision making and continuous improvements to managing the impacts of noise on free-ranging animals.

Do Marine Mammals Experience Stress Related to Anthropogenic Noise?

This paper could not have been written without the financial and organizational support from Dieter Paulmann and Jo Hastie respectively. Thanks are also due to two anonymous reviewers, whose comments on an earlier version of the manuscript greatly improved the paper. The views expressed in this paper are those of the authors alone and do not represent those of Stellwagen Bank National Marine Sanctuary, the U.S. National Marine Sanctuary Program, Southwest Fisheries Science Center, the U.S. National Marine Fisheries Service, NOAA and/or any other institution or agency. Correspondence concerning this article should be addressed to Andrew Wright, Leviathan Sciences, U.S.A. (marinebrit@gmail.com). Sound travels much further than light in the marine environment. As a result, marine mammals, especially cetaceans, rely heavily on sound for many important life functions, including breeding and foraging. This reliance on sound means it is quite likely that exposure to noise will have some detrimental effects on these life functions. However, there has been little application to marine mammals of the knowledge available in other species of stress responses to noise and other stressors. In this paper we begin to integrate what is known about marine mammals with the current knowledge gained in terrestrial mammals about stress physiology, specifically considering physiological and psychological context and thus also cumulative and synergistic impacts. We determined that it is reasonable to extrapolate information regarding stress responses in other species to marine mammals, because these responses are highly conserved among all species in which they have been examined to date. As a result, we determined that noise acts as a stressor to marine mammals. Furthermore, given that marine mammals will likely respond in a manner consistent with other species studied, repeated and prolonged exposures to stressors (including or induced by noise) will be problematic for marine mammals of all ages. A range of issues may arise from the extended stress response including, but not limited to, suppression of reproduction (physiologically and behaviorally), accelerated aging and sickness-like symptoms. We also determined that interpretation of a reduction in behavioral responses to noise as acclimation will be a mistake in many situations, as alternative reasons for the observed results are much more likely. We recommend that research be conducted on both stress responses and life-history consequences of noise exposure in marine mammals, while emphasizing that very careful study designs will be required. We also recommend that managers incorporate the findings presented here in decisions regarding activities that expose marine mammals to noise. In particular, the effects of cumulative and synergistic responses to stressors can be very important and should not be dismissed lightly.

A Brief Review of Anthropogenic Sound in the Oceans

Sound in the oceans is generated by a variety of natural sources, such as breaking waves, rain, and marine animals, as well as a variety of human-produced sources, such as ships, sonars and seismic signals. This overview will begin with a quick review of some basic properties of sound waves with particular reference to differences between the behaviours of these waves underwater versus in air. A basic understanding of the physics of underwater sound is critical to understanding how marine animal acoustic signals have evolved relative to their different functions and how changes in the marine acoustic environment due to increasing anthropogenic sound in the oceans may impact these species. We will then review common sources of anthropogenic sound in the oceans. The frequency contributions of three major sources of underwater anthropogenic sound and their relative intensities will be discussed: naval exercises, seismic surveys and commercial shipping. Finally, a case study examining relative inputs to a regional noise budget, that of the Gerry E. Studds Stellwagen Bank National Marine Sanctuary, will be presented to introduce the audience to methodologies for characterizing and managing sound on an ecosystem level.

Whale tracking underwater: High frequency acoustic pingers and the instrumented tag (DTAG)

Since 2004, scientists have been tagging and tracking humpback whales in Stellwagen Bank National Marine Sanctuary to better understand their behavior. Stellwagen Bank is a shoal area east of Boston and north of Cape Cod, MA where many species of baleen whale feed during the summer months. Instrumented tags (DTAGs) are suction-cupped to the whales back from a RHIB. DTAGS, developed at WHOI, record whale pitch, roll, and heading, 3-D acceleration, depth, and sound for up to 20 h. A pseudotrack for the tagged whale can be generated using visual fixes at the surface and dead-reckoning while the whale is underwater. During extended dives, the solution is expected to exhibit substantial drift, placing limits on the ability to understand feeding behavior, mother-calf interactions, etc. In order to develop higher accuracy whale tracks, three GPS-positioned high-frequency (25–32 kHz) acoustic pingers were deployed around tagged animals in July 2007. The pingers produce time-encoded pulses from known positions, which are recorded along with whale vocalizations and ambient noise on the whale tag. Pulse arrival times from each pinger are converted into ranges from the known pinger locations to generate an underwater whale track. Results from this work will be presented.

Generation and propagation of nonlinear internal waves in Massachusetts Bay

During the summer, nonlinear internal waves (NLIWs) are commonly observed propagating in Massachusetts Bay. The topography of the area is unique in the sense that the generation area (over Stellwagen Bank) is only 25 km away from the shoaling area, and thus it represents an excellent natural laboratory to study the life cycle of NLIWs. To assist in the interpretation of the data collected during the 1998 Massachusetts Bay Internal Wave Experiment (MBIWE98), a fully nonlinear and nonhydrostatic model covering the generation/shoaling region was developed, to investigate the response of the system to the range of background and driving conditions observed. Simplified models were also used to elucidate the role of nonlinearity and dispersion in shaping the NLIW field. This paper concentrates on the generation process and the subsequent evolution in the basin. The model was found to reproduce well the range of propagation characteristics observed (arrival time, propagation speed, amplitude), and provided a coherent framework to interpret the observations. Comparison with a fully nonlinear hydrostatic model shows that during the generation and initial evolution of the waves as they move away from Stellwagen Bank, dispersive effects play a negligible role. Thus the problem can be well understood considering the geometry of the characteristics along which the Riemann invariants of the hydrostatic problem propagate. Dispersion plays a role only during the evolution of the undular bore in the middle of Stellwagen Basin. The consequences for modeling NLIWs within hydrostatic models are briefly discussed at the end.

Stock Identification of Atlantic Cod in U.S. Waters Using Microsatellite and Single Nucleotide Polymorphism DNA Analyses

AbstractManagement of Atlantic cod Gadus morhua in U.S. waters is based on a two‐stock model composed of stocks from (1) the Gulf of Maine (GOM) and (2) Georges Bank (GB) and areas south; however, evidence suggests a more fine‐scale structuring. We used microsatellite and single nucleotide polymorphism (SNP) analyses to investigate the stock structure of Atlantic cod in U.S. waters. In year 1, we analyzed microsatellite loci in larvae from GB, age‐0 juveniles from multiple locations in the GOM, and adults of unknown maturity from GB, Jeffreys Ledge, and the Great South Channel (GSC). In year 2, Atlantic cod collected from spawning aggregations in Ipswich Bay in the spring and at GB, Stellwagen Bank, Chatham, and Ipswich Bay in the winter, along with adults of unknown maturity from Long Island, New York, were surveyed at a modified battery of microsatellites and three SNPs. In year 1, we saw no significant differences in allelic frequencies between our composite sample of adult and juvenile cod from the GOM and that from GB nor between the collections from the GSC and any other site. However, a composite sample of juveniles from Massachusetts Bay was significantly different from the GB collection and juveniles from Maine. In year 2, we found highly significant differences in allelic frequencies between Atlantic cod collections from the GOM and GB. The spring collection from Ipswich Bay was highly distinct from the collection from GB and all other sites, including the winter‐spawning Ipswich Bay collection. The Long Island sample was genetically distinct from the GB and the spring collections from Ipswich Bay, but not from other collections. Our study indicates that there is genetic heterogeneity of stocks in U.S. waters, but its structure is complex and to better understand it many more spatially and temporally separated samples must be characterized.

Large internal waves in Massachusetts Bay transport sediments offshore

A field experiment was carried out in Massachusetts Bay in August 1998 to assess the role of large-amplitude internal waves (LIWs) in resuspending bottom sediments. The field experiment consisted of a four-element moored array extending from just west of Stellwagen Bank (90-m water depth) across Stellwagen Basin (85- and 50-m water depth) to the coast (24-m water depth). The LIWs were observed in packets of 5–10 waves, had periods of 5–10 min and wavelengths of 200–400 m, and caused downward excursions of the thermocline of as much as 30 m. At the 85-m site, the current measured 1 m above bottom (mab) typically increased from near 0 to 0.2 m/s offshore in a few minutes upon arrival of the LIWs. At the 50-m site, the near-bottom offshore flow measured 6 mab increased from about 0.1 to 0.4–0.6 m/s upon arrival of the LIWs and remained offshore in the bottom layer for 1–2 h. The near-bottom currents associated with the LIWs, in concert with the tidal currents, were directed offshore and sufficient to resuspend the bottom sediments at both the 50- and 85-m sites. When LIWs are present, they may resuspend sediments for as long as 5 hours each tidal cycle as they travel westward across Stellwagen Basin. At 85-m water depth, resuspension associated with LIWs is estimated to occur for about 0.4 days each summer, about the same amount of time as caused by surface waves.

Comparison of PCBs, organochlorine pesticides, and trace metals in cod liver from Georges Bank and Stellwagen Bank, USA and Canada

Comparison of PCBs, organochlorine pesticides, and trace metals in cod liver from Georges Bank and Stellwagen Bank, USA and Canada

The Stellwagen Bank region off eastern Massachusetts: a Wisconsin glaciated Cenozoic sand banks/delta?

Stellwagen and Tillies banks, Jeffreys Ledge, the erosional remnants shoreward of the banks in Massachusetts Bay, Cape Cod Bay and beneath Cape Cod may define an Eocene sand banks/delta. The present configuration of the region is due to a combination of pre-Wisconsin fluvial erosion, Wisconsin proglacial, subglacial and marine processes and Holocene marine processes. Wisconsin sediments south of Jeffreys Ledge experienced deformation and the formation of sag basins by the sinking of the overlying sediments into the underlying fine grained mass with the sediments between the basins being squeezed up to producing diapirs. The western part of Jeffreys Ledge rising tens of meters above its surroundings is a moraine created during a local re-advance when the overall Laurentide ice was retreating prior to 14 000 years ago. This re-advance resulted in the deformation of Coastal Plain and Wisconsin strata.

The Distribution and Density of Commercial Fisheries and Baleen Whales within the Stellwagen Bank National Marine Sanctuary: July 2001–June 2002

Research in a national marine sanctuary provides the ability to monitor, assess and understand changes in, and threats to, the area. In July 2001, the Stellwagen Bank National Marine Sanctuary undertook a year-long study to quantify and map patterns of human and marine mammal use. Data were collected during monthly standardized shipboard surveys that bisected the Sanctuary at 5 km (2.5 nm) intervals. We used a subset of those data and ArcView's Spatial Analyst program to conduct an analysis of the density and distribution of fixed gear (trap and gillnet) fisheries, mobile gear (otter trawl and scallop dredge) fisheries and baleen whales. We used this to develop a “user geography” of the Sanctuary based on patterns of use and identify high use areas that might pose the risk of environmental damage. We also used ArcView to develop an index of Relative Interaction Potential (RIP) to identify where baleen whales might become entangled in fishing gear; a known threat within the Sanctuary. The RIP identified a number of areas that stood out in terms of entanglement risk. Information from the study will allow managers to identify future changes in Sanctuary use and investigate current areas of intense use for potential harm.

Site Utilization by Atlantic Cod (Gadus morhua) in Off-Shore Gravel Habitat as Determined by Acoustic Telemetry: Implications for the Design of Marine Protected Areas

We quantified the site utilization of offshore gravel habitat by Atlantic cod (Gadus morhua) using acoustic telemetry. An omni-directional receiver was deployed inside Stellwagen Bank National Marine Sanctuary during Summer 2001 in an area that excluded commercial fishing for demersal fishes. Fish were collected using hook and line, tagged externally with coded acoustic pingers, and released on the seafloor using an “elevator” within the range of the receiver. Observations were made over 120 days. The total number of days that individual fish were recorded was up to 120 days and a total of 37% of all tagged fish showed high site fidelity to the study area.

Variation in Habitat use by Juvenile Acadian Redfish, Sebastes fasciatus

A basic paradigm in behavioral ecology is that organisms expand their distribution as preferred sites become saturated with individuals that reduce the availability of resources (e.g., shelter, prey) on a per capita basis. Previous fish community studies at Stellwagen Bank National Marine Sanctuary have shown that juvenile Acadian redfish Sebastes fasciatus ( 20 cm TL) also occurred in dense cerianthid habitats. Two explanations for these distributions can be advanced. The simplest is that redfish use both boulder and cerianthid habitats on an encounter basis, regardless of habitat saturation or predation pressure. Alternatively, boulder reefs serve as recruitment habitats and cerianthid habitats serve as a conduit for redfish moving away from saturated boulder reef sites, essentially serving as elements of a 'redfish pump'.

Use of sand wave habitats by silver hake

Silver hake Merluccius bilinearis are common members of fish communities in sand wave habitats on Georges Bank and on Stellwagen Bank in the Gulf of Maine. Observations of fish size v. sand wave period showed that silver hake are not randomly distributed within sand wave landscapes. Regression analyses showed a significant positive relationship between sand wave period and fish length. Correlation coefficients, however, were low, suggesting other interactions with sand wave morphology, the range of current velocities, and available prey may also influence their distribution. Direct contact with sand wave habitats varied over diel periods, with more fish resting on the seafloor during daytime than at night. Social foraging, in the form of polarized groups of fish swimming in linear formations during crepuscular and daytime periods, was also observed. Sand wave habitats may provide shelter from current flows and mediate fish–prey interactions.

Mapping the Seabed and Habitats in National Marine Sanctuaries—Examples from the East, Gulf and West Coasts

The National Marine Sanctuary System requires seabed and habitat maps to serve as a basis for managing sanctuary resources and for conducting research. NOAA, the agency that manages the sanctuaries, and the USGS have conducted mapping projects in three sanctuaries (Stellwagen Bank NMS, Flower Garden Banks NMS, and Channel Islands NMS) with an emphasis on collaboration of geologists and biologists from the two agencies and from academic institutions. Mapping of seabed habitats is a developing field that requires the integration of geologic and biologic studies and the use of swath imaging techniques such as multibeam and sidescan sonar. Major products of swath mapping are shaded-relief topographic imagery which shows seabed features in great detail, and backscatter imagery which provides an indication of the types of materials that constitute the seabed. Sea floor images provide an excellent basis for conducting the groundtruthing studies (using video, photo, and sampling techniques) that are required to collect the data necessary for making meaningful interpretative maps of the seabed. The compilation of interpretive maps showing seabed environments and habitats also requires the development of a sea floor classification system that will be a basis for comparing, managing, and researching characteristic areas of the seabed. Seabed maps of the sanctuaries are proving useful for management and research decisions that address commercial and recreational fishing, habitat disturbance, engineering projects, tourism, and cultural resources.