Penobscot Bay Research Articles

Bridging the spawner-recruit disconnect II: Revealing basin-scale correlations between zooplankton and lobster settlement dynamics in the Gulf of Maine

In recent decades, recruitment of young-of-year lobsters to benthic nursery habitats in the Gulf of Maine was regionally synchronized and exhibited correlative links with changes in the abundance of the copepod Calanus finmarchicus, a foundational zooplankton species of the pelagic food web. The spatial scale at which recruitment dynamics were correlated indicated that recruitment processes were not as strongly coupled to trends in spawner abundance as might be expected, but, rather, were influenced by common, ecosystem-scale processes. Here we explored how local- and basin-scale zooplankton dynamics and oceanographic indicators in the Gulf of Maine correlated with lobster settlement indices and each other since the late 1980s. Our analysis indicates that lobster settlement trends in southwestern Gulf of Maine study areas, from Midcoast Maine to Cape Cod Bay, tend to be significantly correlated with basin-wide C. finmarchicus dynamics and the composition of waters entering the Gulf of Maine through the Northeast Channel. In contrast, lobster settlement in the northeastern Gulf, from Penobscot Bay to the Bay of Fundy, tended to correlate more strongly to C. finmarchicus variability in the Bay of Fundy region, which was distinct in earlier years but converged with the broader basin-scale processes in the latter years. Our results are consistent with the hypothesis that the combined effect of climate-related declines in abundance and phenological shifts of C. finmarchicus have contributed to declines in lobster settlement over the past decade, and justify further research into the mechanisms of this interaction. These changes also align with the weakening influence of cold Labrador Slope Water and strengthening effects of warm Gulf Stream waters that precipitated an ecosystem-wide regime shift in the Gulf of Maine over the past decade and may have greater implications for lobster recruitment than previously suspected.

Decadal‐Scale Variability in the Surface Flow of the Gulf of Maine Coastal Current: The Impact of Changing Climate Conditions on Coastal Circulation

AbstractThe Gulf of Maine (GOM) is one of the most productive and ecologically important marine environments on the planet. The Gulf of Maine Coastal Current (GMCC), which stretches along the western side of the GOM from the Bay of Fundy to Cape Cod, plays an important role in supporting this productivity by transporting nutrients, larvae and dinoflagellates southwestward along the Canadian and New England coastlines. Climate change has led to alterations in GOM ecosystems in recent years: GOM water temperatures have warmed and distributions of marine species have shifted. However, the impacts of the changing climate on the circulation within the GOM, including the path and velocity of the GMCC, have remained unclear. Here, we examine data collected by satellite tracked surface drifters and velocity data collected by the NERACOOS buoy array in order to investigate inter‐decadal changes to the flow of the GMCC. We find that over inter‐decadal timescales, the alongshore surface flow of the GMCC has slowed, particularly in the region southwest of Penobscot Bay. The slowdown observed in the GMCC surface flow is most likely attributed to a local strengthening of the southwesterly winds over the time period of interest.

Correction to: Imaging of a possible isolated carbonate build-up (ICB) in Penobscot Bay at anomalous low frequencies

Correction to: Imaging of a possible isolated carbonate build-up (ICB) in Penobscot Bay at anomalous low frequencies

Imaging of a possible isolated carbonate build-up (ICB) in Penobscot Bay at anomalous low frequencies

Imaging of a possible isolated carbonate build-up (ICB) in Penobscot Bay at anomalous low frequencies

The coupled effects of stocking density and temperature on Sea Scallop (Placopecten magellanicus) growth in suspended culture

Despite the profitability of the wild Atlantic Sea Scallop, Placopecten magellanicus, fishery, the U.S. still imports more than 26,000 tonnes of various scallop products annually. Atlantic Sea Scallop (hereafter referred to as scallop) aquaculture is one method of mitigating this imbalance. We examined scallop growth at three sites across the mouth of Penobscot Bay, Maine to determine the coupled effects of lantern net stocking density and temperature on growth and mortality. Scallops were held in high and low (20 and 10 individuals tier−1, respectively) density treatments, and shell height measurements were recorded monthly for one year. We divided the growth rate analysis into three periods: winter - spring, summer, and fall. During summer across all sites, growth rates were 75 % higher in low-density nets than in high-density nets. We observed significant nonlinear relationships between shell height growth rate, temperature, and stocking density. Optimal growth occurred within a window of 10–15 °C. Above this threshold, there was a distinct negative relationship between temperature and growth. Our results highlight the importance of maintaining low densities within nets, particularly during periods of high temperature and growth. However, handling in summer and early fall may lead to mortality. Therefore, we recommend that growers stock nets at low densities in the spring, ensuring that they will not require thinning during peak temperatures. Similarly, finding sites that maximize time within a thermal envelope of 10–15 °C will be critical, which in the case of the Gulf of Maine will most likely warrant leasing sites at the mouths of estuaries and bays. These locations offer a combination of sufficient depth and space for sparsely stocked nets, adequate food levels, and optimal salinity and temperature.

Deglaciation of Penobscot Bay, Maine, USA

The Pond Ridge and Pineo Ridge moraines in downeast Maine likely formed at ~16.1 and ~15.7 ka respectively, during cold episodes recorded by δ18O dips in the GRIP ice core. The elapsed time between these ages is broadly consistent with retreat rates recorded by intervening De Geer moraines, which are readily visible on LiDAR imagery and are believed to be approximately annual. North-northwestward from the southwesterly extension of the Pond Ridge moraine there are three pairs of prominent moraines that are relatively continuous across the study area and could be reliably extrapolated across intervening water bodies. Retreat rates recorded by De Geer moraines suggest that these pairs formed at 15.7-15.8 ka, 15.5-15.6 ka, and ~15.5 ka. Although retreat appears to have occurred slightly faster across Penobscot Bay, a significant calving bay does not seem to have developed there. Instead, the ice margin remained relatively straight, retreating to the north-northwest. De Geer moraines become more widely spaced northward and vanish after ~15.5 ka when the ice margin was north of the head of Penobscot Bay and of Pineo Ridge. This likely reflects higher retreat rates during the initial phases of the Bølling warm period. Just south of Pineo Ridge there were two ice lobes; one retreated to the north and one to the northwest. The latter retreated more rapidly, while the former experienced numerous minor readvances and stillstands until finally pausing at the location of Pineo Ridge. A stillstand of this lobe then resulted in deposition of the Pineo Ridge moraine complex.

A view of physical mechanisms for transporting harmful algal blooms to Massachusetts Bay

Physical dynamics of Harmful Algal Blooms in Massachusetts Bay in May 2005 and 2008 were examined by the simulated results. Reverse particle-tracking experiments suggest that the toxic phytoplankton mainly originated from the Bay of Fundy in 2005 and the western Maine coastal region and its local rivers in 2008. Mechanism studies suggest that the phytoplankton were advected by the Gulf of Maine Coastal Current (GMCC). In 2005, Nor'easters increased the cross-shelf surface elevation gradient over the northwestern shelf. This intensified the Eastern and Western MCC to form a strong along-shelf current from the Bay of Fundy to Massachusetts Bay. In 2008, both Eastern and Western MCC were established with a partial separation around Penobscot Bay before the outbreak of the bloom. The northeastward winds were too weak to cancel or reverse the cross-shelf sea surface gradient, so that the Western MCC carried the algae along the slope into Massachusetts Bay.

Detrital zircon signatures in Precambrian and Paleozoic sedimentary units in southern New Brunswick – more pieces of the puzzle

Southern New Brunswick consists of a complex collage of fault-bounded belts of Late Neoproterozoic igneous and metamorphic rocks, Early Paleozoic sedimentary, metamorphic and igneous units, and overlying Carboniferous sedimentary rocks. The area also contains the boundary between the Avalonian and Ganderian terranes as interpreted in the northern Appalachian orogen. New detrital zircon ages reported here provide improved understanding of depositional ages and provenance of diverse Neoproterozoic to Carboniferous rocks in this complex area. Detrital zircon data from samples with Neoproterozoic maximum depositional ages indicate a dominantly Gondwanan provenance with a strong influence from the Amazonian craton. However, quartzite from The Thoroughfare Formation on Grand Manan Island contains dominanly 2 Ga zircon grains, consistent with derivation from the West African Craton. The age spectrum is similar to that from the Hutchins Island Quartzite in the Isleboro block in Penobscot Bay, Maine, strengthening the previously proposed correlation between the two areas. Cambrian samples also show prominent peri-Gondwanan provenance with strong influence from Ediacaran to Early Cambrian arc magmatism. The maximum depositional ages of these samples are consistent with previous interpretations of Cambrian ages based on fossil correlations and field data. A Carboniferous sample from Avalonia shows a significant contribution from Devonian magmatism as the youngest detrital component, although its depositional age based on field relationships is Carboniferous. The results exemplify the need to integrate multiple datasets in making interpretations from detrital zircon data.

Phylogeography of Neomysis americana (Crustacea, Mysida), focusing on the St. Lawrence system

AbstractSpecies characterized by low dispersal capacities, such as mysids, usually show evidence of genetic differentiation. Many mysids are broadly distributed and often show eurythermal and euryhaline traits. This study aimed to describe intraspecific genetic structure and the phylogeography of Neomysis americana, a key species of estuarine food webs in northwest Atlantic, using the mitochondrial cytochrome c oxidase subunit I gene. We sampled 26 populations across the St. Lawrence system (SLS) and two along the east coast of North America [Penobscot and Chesapeake Bay (CB)]. Sequencing of 420 individuals revealed three divergent (>3%) lineages (LA, LB, LC) across the sampling area suggesting that N. americana represents a cryptic species complex. The distribution of the lineages was geographically structured. LC occurred in the CB only, whereas LA and LB co-occurred along the SLS and Penobscot Bay. This suggests secondary contact after the last glacial maximum. In the SLS the lineage LA dominated the estuarine transition zone and the Gulf of St. Lawrence, whereas the lineage LB was prevalent in the lower St. Lawrence Estuary, potentially due to different eco-physiological preferences. These results might help to define reasonable entities for research and management.

Neoproterozoic U–Pb (zircon) and 40Ar/39Ar (muscovite) ages from granitic pegmatite clasts, basal Ross Island Formation, Grand Manan Island, New Brunswick, Canada

Zircon grains from a granitic pegmatite clast from conglomerate at the base of the Ross Island Formation on Grand Manan Island indicate an igneous crystallization age of 664.1 ± 4.6 Ma. The clast also contains abundant older inherited grains back to the Archean. Muscovite in the same clast and an additional similar clast yielded cooling ages of 607.0 ± 3.7 Ma and 619.6 ± 4.1 Ma, respectively, providing a maximum depositional age for the host conglomerate of the Ross Island Formation. The similarity in age to pegmatite in the Seven Hundred Acre Island Formation in Penobscot Bay, Maine, supports earlier correlations between the two areas based on similarities in Neoproterozoic quartzite and carbonate units.

U–Pb zircon geochronology of Proterozoic and Paleozoic rocks, North Islesboro, coastal Maine (USA): links to West Africa and Penobscottian orogenesis in southeastern Ganderia?

Within the Ganderian inlier of Penobscot Bay, coastal Maine, the Islesboro fault block occupies a central position between the St. Croix terrane of continental affinity and, to the east, the Ellsworth terrane of oceanic affinity. New field, petrographic, geochemical, and U–Pb LA-ICP-MS geochronological data on detrital and magmatic zircon grains constrain the provenance and transfer history of these terranes from Gondwana to the Appalachian margin of Laurentia. On North Islesboro, the Coombs Limestone and Hutchins Island Quartzite (new name), intruded by E-MORB amphibolite, constitute a newly recognized local inlier of Proterozoic basement. Together with the nearby Seven Hundred Acre Island Formation, these mature, carbonate-rich strata record deposition on a low-latitude passive margin. Abundant detrital zircon grains in the Hutchins Island Quartzite, all older than ca. 1.8 Ga, have a predominant population at ca. 2.0 Ga and a small peak between ca. 2.8 Ga and 2.4 Ga, an age spectrum strikingly similar to those of both the Paleoproterozoic Taghdout Quartzite in Morocco, on the West African craton, and basement rocks from Georges Bank, offshore Massachusetts. The overlying Neoproterozoic–Cambrian Islesboro Formation records a second period of extension (interstratified EMORB greenstone) synchronous with accumulation of interbedded siliciclastic and carbonate sediment, prior to recumbent folding. At the base of the moderately deformed Turtle Head Cove (new name) cover sequence, immature greywacke has a youngest zircon population of ca. 515 Ma, large late Neoproterozoic populations (ca. 624 Ma and 678 Ma), a small peak at 1.2 Ga, a moderate number of ca. 1.5 Ga to 2.0 Ga grains, and a few Late Archean grains. Compared with many similar Ganderian age spectra reported from Vermont to New Brunswick, which are all consistent with a source in either the Amazonian or West African cratons, this new age spectrum most closely resembles those from quartzites in the Grand Manaan and Brookville terranes of coastal New Brunswick. Significantly, exotic blocks lithologically indistinguishable from Proterozoic strata on Islesboro occur in the St. Croix terrane within a Lower Ordovician black shale mélange at the base of the Penobscot Formation, suggesting that the St. Croix terrane, Islesboro block, and Ellsworth terrane were initially juxtaposed by Penobscottian thrusting prior to the Middle Ordovician. Subsequently, the Islesboro block was isolated between the bounding post-Silurian, pre-Late Devonian Turtle Head and Penobscot Bay dextral strike-slip faults. Along the North Islesboro fault, a fault-bounded lens of foliated pyritic felsic volcanic and volcaniclastic rock, dated at ca. 372 Ma and containing Devonian to Archean detrital zircons, records late Paleozoic deformation recognized previously in coastal New Brunswick but not in Penobscot Bay.

Evidence for major input of riverine organic matter into the ocean

The changes in the structure of XAD-8 isolated dissolved organic matter (DOM) samples along a river (Penobscot River) to estuary (Penobscot Bay) to ocean (across the Gulf of Maine) transect and from the Pacific Ocean were investigated using selective and two dimensional (2D) nuclear magnetic resonance (NMR) spectroscopy coupled with elemental and carbon isotope analysis. The results provide important insights into the nature of relatively stable structures in the river-to-ocean continuum and the enigma of the fate of terrestrial DOM in the marine system. First, lignin and carboxyl-rich alicyclic molecules (CRAMs), which are indistinguishable from mass spectrometry, were clearly differentiated with NMR spectroscopy. NMR unambiguously showed that CRAMs persisted along the river-to-ocean transect and in the Pacific Ocean, while lignin residues dramatically decreased in abundance from the river to the coastal ocean and the Pacific Ocean. The results challenge a previous conclusion that lignin-derived compounds are refractory and can accumulate in the coastal ocean. The loss of terrestrial plant-derived aromatic compounds such as lignin and tannin residues throughout the sequence of riverine, coastal, and open ocean DOM extracts could also partially explain the decreasing organic carbon recovery by XAD-8 isolation and the change in carbon stable isotope composition from riverine DOM (δ13C −27.6‰) to ocean DOM (δ13C −23.0‰) extracts. The observation, from advanced NMR, of similar CRAM molecules in XAD-8 isolated DOM samples from the Penobscot River to the Penobscot Bay and from the ocean refutes a previous conclusion that XAD-isolated DOM samples from seawater and river are distinctly different. The alicyclic structural features of CRAMs and their presence as the major structural units in DOM extracts from the Penobscot River to Gulf of Maine transect, together with the deduced old 14C age of CRAMs in the ocean, imply that terrestrial CRAMs may persist on timescales long enough to be transported into the ocean.

Late- and Post-glacial history of the East Branch of the Penobscot River, Maine, USA

Between ~20 and 15 ka the Laurentide Ice Sheet retreated from the edge of the continental shelf, ἀrst to the Maine coast and then across Maine to the northern reaches of the Penobscot Lowland. The Lowland, being isostatically depressed, was inundated by the sea. As ice then retreated into Maine’s western mountains, valleys through the mountains became estuaries. In the estuary now occupied by the Penobscot River’s East Branch, ten ice-marginal deltas were built during pauses in this part of the retreat. By 14 ka the ice had retreated far enough to expose land in the valley bottom between the ice front and the sea, and the Penobscot River was (re)born. This occurred near the present conᴀuence of the Seboeis River and the East Branch. The river gradually extended itself northward as the ice retreated and southward as relative sea level fell. Braidplains were formed and incised, leaving terraces. High initial discharges eroded the eastern ᴀanks of the esker and deltas, redepositing silt, sand, and gravel all the way to the present head of Penobscot Bay. By ~10 ka the discharge had decreased, the river was adjusting to on-going differential isostatic rebound, and finer sediment was accumulating, forming the present floodplain.

Handling and Tagging Effects, In‐River Residence Time, and Postspawn Migration of Anadromous River Herring in the Hudson River, New York

AbstractIn a 2013 pilot study, acoustic tags were inserted into two species of river herring, Alewife Alosa pseudoharengus and Blueback Herring Alosa aestivalis. The primary objectives were to identify handling and tagging effects and assess in‐river residence time. The secondary objective was to identify postspawn coastal migration patterns. Fish were collected on spawning grounds in the upper portion of the Hudson River, New York. Vemco V7 acoustic transmitters were gastrically inserted into 25 river herring (13 Alewives and 12 Blueback Herring) that were in pre, active, or post spawning conditions. In‐river acoustic data were collected from 23 of the 25 river herring. The majority of tagged fish exhibited some level of fallback (downstream migration) after the tagging event, all Blueback Herring and all male Alewives returning to spawning areas. The majority of female Alewives did not return to the spawning area after tagging, and this may be a result of when and where tagging events occurred. Both species of river herring exhibited similar in‐river residence times of approximately 2–3 weeks and exited the system 3–6 d after spawning. Information on coastal movements of four Blueback Herring (two females and two males) was also obtained, spanning the south shore of Long Island, New York, to the mouth of Penobscot Bay, Maine. Coastal and in‐river tag detections were reported by members of the Atlantic Cooperative Telemetry Network. In conclusion, this experiment can now be repeated with confidence on a larger scale with multiyear tags in order to identify unknown in‐river spawning areas, provide information regarding spawning site fidelity, and bolster current knowledge of coastal migration patterns for both species.

Late glacial and Holocene history of the Penobscot River in the Penobscot Lowland, Maine

When the Laurentide ice sheet retreated rapidly (~150 m/a) across the Penobscot Lowland between ~16 and ~15 ka, the area was isostatically depressed and became inundated by the sea. Silt and clay were deposited, but no significant moraines or deltas were formed. The Penobscot River was reborn at ~14 ka when ice retreated onto land in the upper reaches of the river’s East Branch. As isostatic rebound exceeded sea level rise from melting ice, the river extended itself southward. Between ~13.4 and 12.8 ka, it established a course across marine clay and underlying glacial till in the Lowland. Its gradient was low as differential rebound had not begun. Discharge, however, was higher and the river transported and deposited outwash gravel. During the cold, dry Younger Dryas, ~11 ka, eolian sand began to accumulate in dunes in the Lowland. Some of this sand, along with fluvial sediment from the headwaters, was redistributed into terraces along gentler stretches of the river and into a paleodelta in Penobscot Bay. Eolian activity continued to ~8 ka and aggradation in terraces until ~6 ka. The climate became wetter and warmer after ~6 ka, the dunes were stabilized by vegetation, the river began to downcut, and braiding became less intense. Pauses in the downcutting are reflected in discontinuous strath terraces. In due course, the river re-encountered the old outwash gravels, marine clay, glacial till, and, in a few places, bedrock. Its profile is now stepped, with gentle, gravel-bedded reaches between bedrock ribs that form rapids.

LIVING IN HARMONY WITH NATURE

INTRODUCTION Mount Desert Island is one of the most beautiful places in New England. Situated in the middle of Penobscot Bay in Maine, which is home to Acadia National Park, one of the most visited parks in the National Park system. The landscape is classic Maine, with evergreen trees clinging to a rocky coastline. Over the past 150 years it has been a summer retreat for many, including the Rockefellers who helped create the carriage trails in the Park, and home to the infamous “cottages” of the wealthy that came to the Island starting in the second half of the nineteenth century to escape the hot summer temperatures of the cities. It was on this island, in this historic setting, that Pondicherry was created. With a love of this unique place and a desire to find a way to live here in harmony with the natural setting, the owners sought out Scott Simons Architects to help them design a unique house, one that would combine aesthetic beauty and ultra high environmental performance. They were looking to create...

Eelgrass,Zostera marina, as essential fish habitat for young-of-the-year winter flounder,Pseudopleuronectes americanus(Walbaum, 1792) in Maine estuaries

Distribution and density by habitat for age-0, young-of-the-year (YOY) winter flounder, Pseudopleuronectes americanus (Walbaum, 1792), were compared for two Maine estuaries to help define essential fish habitat for this life history stage. Two estuaries (Weskeag River and Penobscot Bay) along Mid-coast Maine were sampled monthly with daytime 1.0 m2 fixed-frame throw traps around neap low tide, May–December over two consecutive years (2003–2004). Both eelgrass and adjacent sand/mud (20–60 cm deep) were randomly sampled with equal effort (4–12 samples per month) at two sites in both the Weskeag River and Penobscot Bay. Significantly higher densities of YOY winter flounder (2–9 cm TL) occurred in eelgrass relative to sand/mud. Density increased significantly in both habitats in 2004, and was higher in Penobscot Bay relative to the Weskeag River. YOY densities compared by eelgrass coverage within throw traps were found to be significantly higher in eelgrass that exceeded 30% coverage when compared with adjacent sand/mud areas and eelgrass coverage of 10–20%. YOY occurred in all months sampled (May–December); no density differences existed by month. These results indicate that very shallow (<0.6 m) eelgrass habitat is of key importance to YOY winter flounder in Maine estuaries and should be viewed as essential fish habitat (EFH) for this species and life stage.

“This Long Looked For Event”: Retrieving Early Contact History from Penobscot Oral Traditions

“This Long Looked For Event”:Retrieving Early Contact History from Penobscot Oral Traditions Annette Kolodny (bio) WHEN JOSEPH NICOLAR TOOK UP THE TASK of telling the story of his people from the first moments of the creation of the world by the Great Spirit through the several arrivals and eventual permanent settlement of the white man in “the red man’s world,” he made clear at the outset that his was no act of colonial mimicry (2007, 95). First published in 1893, The Life and Traditions of the Red Man neither replicated nor followed the history Nicolar had been taught in the white man’s schools (95).1 As he emphatically declared in the first sentence of his preface, “there have been no historical works of the white man, nor any other written history from any source quoted” (95). In Nicolar’s experience, even after more than two centuries of contact and colonialism, the world of the red man remained for the white man “as hidden things” (95). Therefore, “all prophecies, theories and ideas of the educated and intelligent of all races have been laid aside,” Nicolar explained. The authority for his work rested in “the traditions as I have gathered them from my people” after “forty years of search and study” (95, 96). As a descendant of “that once numerous and most powerful race, … my life having been spent in the researches of my people’s past life,” Nicolar saw himself as ensuring that the story of the red man would not “pass away unwritten” (95). But how shall we understand his rendering of his “people’s past life”? Is there any sense in which that “past life,” so obviously anchored in Penobscot oral storytelling practices, can also be read as history? Or, to put it another way, does Nicolar’s retelling of Penobscot traditions offer us any new understanding of the long and complex realities of the Penobscot past? And, more specifically, can these Penobscot oral traditions contribute to a history of early Native and European contacts that is at once more accurate and also more ethical than the mythology of a Columbian “first discovery” still so prevalent in too many of our schools and schoolbooks? In a thoughtful and probing essay on “merging European and Native views of early contact,” published in 2001, Canadian anthropologist Toby Morantz posed similar questions: “Can there be a single history that reflects both perspectives? The one draws on a rich, ancient oral tradition, and the other on [End Page 90] an equally rich, relatively ancient recorded one, but each is embedded in radically different cultural contexts” (49). After examining both Innu/Cree and Euro-Canadian materials, Morantz finally concluded “that it is impossible” (64). This essay challenges that conclusion. By focusing on both Native and European narratives about early encounters along the coast of Maine, I hope to gesture toward a new kind of history that honors what I call the experiential knowledge embedded in Indigenous traditions. This leads inevitably to the decoupling of the concepts of “contact” and “discovery” as one and the same thing. And this approach also effectively deconstructs the by-now oversimplified construction of “contact” as always and everywhere a first contact, that is, an event singular and unprecedented. Finally, I will point to the experiential knowledge embedded in Indigenous oral historiography as additional evidence that the fifteenth-century Doctrine of Discovery, as applied in the Americas, was often no more than a fiction dressed in legal costume. Lands Where No “Christian Had Been Before” In 1605, at the behest of a group of Catholic investors in England, Captain George Waymouth explored the islands and coastal waterways of Maine in search of a suitable location to plant a new colony. On board Waymouth’s ship was James Rosier, a Catholic priest who recorded a dated running narrative of their journey which was published that same year in London under the title A True Relation. According to Rosier, as they explored the Penobscot Bay area, Waymouth’s company “diligently observed, that in no place, about either the Islands, or up in the Maine, or alongst the river, we could not discerne any token or signe, that ever any...

Seal‐Induced Injuries on Adult Atlantic Salmon Returning to Maine

AbstractSeals (Phocidae) are known predators of Atlantic Salmon Salmo salar from their entry into the estuary as smolts until their return to freshwater as adults. We developed a written protocol for identifying seal‐induced injuries on adult Atlantic Salmon returning to Maine rivers. The protocol, which includes photos and category definitions, has been used since 2006 by Maine Department of Marine Resources biologists when handling adult Atlantic Salmon at the Veazie Dam fishway on the Penobscot River and at other adult capture facilities in Maine. The written protocol has ensured that reporting is consistent among years and rivers; photos of wounds serve as quality assurance for the protocol. For adults returning to the Penobscot River in 2006 and 2007, seal‐induced injuries were more likely to be found on two‐sea‐winter fish; to appear as gashes or arched wounds; to be open rather than healed; and to occur on the center third of the body below the lateral line. Larger two‐sea‐winter fish (&gt;67 cm FL) returning to the Penobscot River early in the run (May–early July) were more likely to have a seal‐induced injury. Injury rates increased from 1978 to 2010; this increase was correlated with seal aerial counts for the Gulf of Maine and Penobscot Bay. From 2006 to 2010, the annual seal‐induced injury rate for Atlantic Salmon in six Maine rivers (including the Penobscot River) ranged from 0.00 to 0.30 across rivers. Rates of injury on Atlantic Salmon for all years combined did not differ among the six rivers, but low power likely affected our ability to detect any differences.Received July 25, 2013; accepted February 5, 2014

Spatial Variability of Metal Bioaccumulation in Estuarine Killifish (Fundulus heteroclitus) at the Callahan Mine Superfund Site, Brooksville, ME

The former Callahan Mine Site in Brooksville, ME, is an open-pit, hardrock mine site in an intertidal system, thus providing a unique opportunity to evaluate how metal-enriched sediments and overlying water impact estuarine food webs. Copper, zinc, cadmium, and lead concentrations in sediment, whole water, and Atlantic killifish (Fundulus heteroclitus) were evaluated at sites in Goose Pond (GP; Callahan Mine Site) and at reference sites. The metal concentrations of sediment, water, and fish were spatially distinct and significantly greater at the mine site than in the reference estuary. Sediment concentrations were particularly elevated and were above probable effects levels for all four metals adjacent to the tailings pile. Even in this well-mixed system, water metal concentrations were significantly elevated adjacent to the tailings pile, and concentrations of Cu and Zn were above ambient water-quality criteria for chronic marine exposure. Neither organic matter in the sediment nor salinity or pH of the water explained the metal concentrations. Adjacent to the tailings pile, killifish metal body burdens were elevated and were significantly related to both sediment and aqueous concentrations. In conclusion, (1) the contaminated sediment and seepage from the tailings impoundment and waste rock pile no. 3 create a continual flux of metals into the water column, (2) the metals are bioavailable and bioconcentrating as evident in the killifish tissue concentrations, and (3) Callahan Mine is directly affecting metal bioaccumulation in fauna residing in the GP estuary and, potentially, in Penobscot Bay by the way of “trophic nekton relay.”