Grand Manan Research Articles

Pop-up satellite archival tags and an individual-based model provide new insights on behavioural thermoregulation in migrating ovigerous American lobster

Ovigerous American lobsters, Homarus americanus, in the Bay of Fundy undertake seasonal migrations, which are thought to improve the thermal conditions experienced by their embryos. However, the complete thermal and bathymetric history of such females has never been characterized. To this end, we deployed pop-up satellite archival tags on two ovigerous females (160 mm carapace length) in the Bay of Fundy between September 2013 and July 2014. Tagged lobsters traveled from the release location (Grand Manan, New Brunswick) to points near Beaver Harbour, New Brunswick, and Port George, Nova Scotia, representing linear displacements of 33 and 123 km, respectively. Recorded depth and temperature for both lobsters confirm shallow-to-deep migrations in the fall and deep-to-shallow migrations in the spring. The high-resolution, nearly continuous data generated by the satellite tags indicated that local changes in temperature may be the proximate trigger for fall movements, but do not cue movements in spring. We then developed an individual-based model to investigate the mechanisms and thermal outcomes of seasonal migrations, where lobster movements were allowed to vary according to bottom temperature, an individual's level of preference for warmer waters and its scope for movement. This modeling work, combined with the fine-scale thermal and depth history of our tagged lobsters, indicated that the movements our lobster undertook clearly increased, but did not maximize, the temperature their embryos experienced, relative to lobsters moving randomly or not at all. The novel data and modeling approach used in this study shed new light on the nature, trigger and function of seasonal migrations displayed by American lobsters in the Bay of Fundy.

Drivers of decadal-scale temporal change in epibenthic megafaunal assemblages on scallop fishing grounds in the Bay of Fundy

The Bay of Fundy presents a unique environment with extreme tidal range, strong currents, fresh-water river discharge, and diverse habitats that are also experiencing temperature increase at a faster rate than most of the world ocean. There is extensive commercial fishing, valuable beds of sea scallop (Placopecten magellanicus) being found in several areas, some of which have been fished for over a century. Previously, comparative analyses of data collected in 1967 and 1997 found that the epibenthic assemblage on the Digby scallop ground had become more homogenous over the 30 year interval, while species composition had changed significantly. Attached, fragile, epifaunal taxa declined, whereas scavengers and robust burrowing filter-feeders increased in frequency of occurrence, consistent with the physical impacts of fishing gears as a primary driver. The Digby ground along with the commercial scallop grounds around Grand Manan Island and on Lurcher Shoal were resampled in 2007–08 to determine whether the changes off Digby had continued and if they were also occurring in other parts of the Bay. Significant spatial differences among the three scallop grounds were observed. The leafy bryozoan, Flustra foliacea, which was expanding its local range through time, was the leading contributor to the spatial dissimilarity. Depth and mean tidal current speed were the most important environmental variables influencing species composition. Significantly more taxa were recorded per station in 1997 than in 2007–08, while assemblage compositions were significantly different between the two periods. Decadal-scale declines in the frequencies of occurrence of attached, epibenthic filter-feeders, including the polychaete Filograna implexa, were observed, continuing the trend previously reported and consistent with on-going impacts of bottom-contact fishing gears, despite decades of trawling and dredging. However, other and unknown drivers were also implicated in the observed changes.

Seasonal Variations and Driving Factors of the Eastern Maine Coastal Current

AbstractTo investigate the coastal current in the Gulf of Maine (GoME) and its relation to forcing from outside of the gulf, a high‐resolution circulation model was developed and validated. Our model shows that the Eastern Maine Coastal Current (EMCC) possesses two cores, an offshore and a nearshore core that peak in summer and spring, respectively. The two cores can be traced back to outflows from the Bay of Fundy from opposite sides of Grand Manan Island, and both cores are deeper and slightly more onshore in summer and fall in response to tidal mixing, surface thermal stratification and wind. The two cores merge south of Pleasant Bay, then split into two branches again east of Mount Desert Rock, where the nearshore branch flows along the coast, while the offshore branch turns southward to recirculate in the eastern GoME. Subject to variations of Scotian Shelf Water and Slope Water (SW) inflows, the offshore veering occurs further upstream (northeastward) in late winter and summer, but gradually shifts downstream (southwestward) from summer to winter. Diagnosis of momentum balance demonstrates that the EMCC is primarily driven by the pressure gradient force (PG), of which the barotropic PG is dominant and offshore, while the baroclinic PG is onshore and increases with depth. The large baroclinic PG at depths, modulated by SW, that is, blended by tidal mixing, offsets the barotropic PG. Near the surface, the barotropic PG is nearly balanced by the Coriolis force, forming the geostrophic EMCC.

Petrology and age of the Lepreau River Dyke, southern New Brunswick, Canada: source of the end-Triassic Fundy Group basalts

A large dyke of quartz tholeiitic gabbronorite has been mapped for 59 km in southern New Brunswick, Canada, between Lepreau River in the northeast and Indian Island in the southwest. Scattered outcrops occur along a positive aeromagnetic lineament, providing a dyke strike of N42°E overall (segments N30°E to N72°E), dips of 80° to 90°NNW, and widths of 4 to 30 m. A new 40Ar/39Ar plagioclase age of 201.67 ± 0.35 Ma for the Lepreau River Dyke is similar to dates for the massive North Mountain Basalt in the Fundy Basin to the east. The dyke is associated with the Ministers Island and Christmas Cove dykes, which are indistinguishable in chemistry, petrology, and probable age, and we regard them as segments of the same co-magmatic dyke system. In addition, their petrology is similar to that of the basalts of the adjacent Early Mesozoic Fundy and Grand Manan basins. We propose that the Lepreau River and associated dykes were sources for the regional basin basalts, which in turn are part of the Central Atlantic Magmatic Province (CAMP) that overlaps the Triassic–Jurassic boundary and associated mass extinction event.

A histology-free description of Tetrastemma cupido sp. nov. (Nemertea: Eumonostilfera) from Sagami Bay, Japan

ABSTRACT We provide a histology-free description of the eumonostiliferous hoplonemertean Tetrastemma cupido sp. nov. based on specimens collected subtidally at a depth of 100 m in Sagami Bay, Japan. In T. cupido sp. nov., the ocelli are arranged in two, anterior and posterior, pairs of clusters, each consisting of up to eight and four ocelli, respectively. This feature is unique to T. cupido sp. nov. among ∼110 congeners in the genus Tetrastemma Ehrenberg, 1828, where the ocelli are unexceptionally four in number. The generic affiliation of the new species was confirmed with a molecular phylogenetic analysis based on partial sequences of cytochrome c oxidase subunit I, 16S rRNA, 18S rRNA and 28S rRNA genes among 31 species of eumonostiliferans. In the resulting tree, T. cupido sp. nov. was nested in a clade comprised of 11 species of Tetrastemma including the type species Tetrastemma flavidum Ehrenberg, 1828. Tetrastemma cupido sp. nov. is morphologically similar to Amphiporus superbus (Girard in Stimpson W. 1854. Marine Invertebrata of Grand Manan. Smithsonian Contr Knowl. 6:5–67), but can be distinguished from the latter by having a mid-dorsal white stripe. Publication LSID: lsid:zoobank.org:pub:C58863AC-6176-453C-94EA-BD79D413EF41

Estimated Abundance of Hydrobates leucorhous (Leach's Storm-Petrel) on Hay Island, New Brunswick

Hydrobates leucorhous (Leach's Storm-Petrel) is widely distributed throughout the Northern Hemisphere, but its North American populations are declining. The causes and extent of the decline are uncertain, making continued population monitoring and identification of colonies a priority for the management of this species. Detailed long-term studies of a large colony on Kent Island in the Grand Manan Archipelago, NB, Canada, have been ongoing since the 1930s, yet the presence and abundance of petrels nesting on neighboring islands is poorly documented. We conducted a census of Hay Island, which is connected to Kent Island by a 300-m stretch of intertidal zone, during mid-incubation in July of 2018 to determine burrow densities and occupancy rates and estimate the breeding population size. We estimated the population of breeding pairs to be 2786 (95% CI ± 624), with most active burrows and the highest burrow occupancy rates occurring in open, non-forested areas dominated by Dryopteris spp. (wood ferns). Overall burrow densities and occupancy rates on Hay Island were lower than nearby colonies. Baseline population estimates of Leach's Storm-Petrels in unassessed colonies like Hay Island are important for on-going monitoring, improving regional population estimates, and conservation planning.

State-space modeling for inter-site spread of sea lice with short-term population predictions

Accurate predictions for sea lice abundance can have a great impact on effective management of the parasite. Sea lice data are often from multiple production cycles coming from different aquaculture sites and exhibit strong process and observation variations, presenting challenges in developing effective prediction tools. Reliable predictions of sea lice abundance on aquaculture sites can save money and efforts in organizing effective control measures. A quantitative evaluation of different methods for estimating sea lice infestation pressure on aquaculture sites was presented in a preparatory paper (Elghafghuf et al., 2020). In the current work, we used the favored method for infestation pressure and predicted future sea lice abundances on different parasitic life stages at the site level using a multivariate state-space model fitted to data from aquaculture sites located near Grand Manan Island in the Bay of Fundy, New Brunswick, Canada. We employed a rolling prediction procedure that did not require the prediction model to be refitted to the data at each time of prediction and compared our results with those from a similar approach involving re-estimation of the model at each prediction. The accuracies of predictions were assessed based on hold-out samples of data, whereby the predictions were computed without prior knowledge of these observations. The results showed that the non-updated-model procedure gave short-term (six weeks) predictions with reasonable accuracy, albeit lower prediction errors could be obtained with the updated-model approach. The performance of the non-updated-model prediction, as well as its practical and computational advantages, suggests it to be well suited for user-friendly implementation linked to underlying database. Additionally, the research quantified the contributions of predictive covariates such as infestation pressures to the sea lice predictions.

Stable Isotope Analysis Supports First Occurrence of a Wild-Origin Greylag Goose (Anser anser) to Make Landfall in North America

In North America, the Greylag Goose (Anser anser) has been added to the list of vagrant North American waterfowl based on a bird observed in 2005 on a stationary oil ship in the Atlantic Ocean 167 km southeast of the island of Newfoundland, and on single birds observed in Connecticut and Nova Scotia in 2009 and 2010, respectively. Here, feather and toe-claw hydrogen isotope values (δ2H) linked to spatial hydrological hydrogen isotope patterns are used to demonstrate the origin of the first probable wild-origin Greylag Goose known to make landfall in North America. The bird in question, shot by hunters on Grand Manan Island, New Brunswick, in December 2007 and subsequently deposited at the New Brunswick Museum (specimen NBM 11143), was identified as Anser anser and potentially a wild-origin bird. Isotope data indicates the bird is of probable Greenlandic origin. This supports and pre-dates recent (2014) reports of the Greenlandic molting of Icelandic Greylag Geese, until recently believed to molt exclusively on Iceland. Greylag Geese recorded in North America appear to be part of a pattern of increasing numbers and diversity of geese of northeastern Atlantic origin detected in eastern North America in recent decades.

Estimating sea lice infestation pressure on salmon farms: Comparing different methods using multivariate state-space models

Sea lice are ectoparasites of salmonids, and are considered to be one of the main threats to Atlantic salmon farming. Sea lice infestation on a farm is usually initiated by attachment of the free-living copepodid stage derived from the surrounding water, frequently originating from adult lice on the same farm or from neighboring salmonid farms, referred to as internal and external sources, respectively. Various approaches have been proposed to quantify sea lice infestation pressure on farms to improve the management of this pest. Here, we review and compare five of these methods based on sea lice data from 20 farms located near Grand Manan island in the Bay of Fundy, New Brunswick, Canada.Internal and external infestation pressures (IIP and EIP, respectively) were estimated using different approaches, and their effects were modeled either by a unique parameter for all production cycles or by different parameters for each production cycle, using a multivariate state-space model. Predictive variables, such as water temperature and sea lice treatments, were included in the model, and their effects across production cycles were estimated along with those of other model parameters. Results showed that models with only EIP explained the variation in the data better than models with only IIP, and that models with unique IIP and unique EIP for all cycles were generally associated with the best model fit. The simplest, fixed lag method for calculating infestation pressure had the best predictive performance in our models among the methods studied.

Predicting Internal Solitary Waves in the Gulf of Maine

AbstractInternal solitary waves (ISWs) are important physical processes in the Gulf of Maine (GoM), which is one of the most productive ecosystems of the Northwest Atlantic. In order to understand the roles that ISWs play, it is necessary to have synthesized knowledge of their timing and distributions. We detail the ISW spatial distribution patterns in the GoM using modern high‐resolution satellite imagery. A prediction methodology is suggested based on the speed of mode‐1 ISWs, which is cross validated using three methods: Remote sensing based on positional displacements of ISWs strips in continuous images, theoretical analysis based on climatological ocean stratification, and an empirical method based on bathymetry. Prediction accuracy is further validated by independently collected high spatial resolution satellite images from multiple sensors. We found a new‐generation site for ISWs near Grand Manan, with wave crests extending over the entire GoM. Interference of ISWs originating from the new‐generation site and the well‐known generation location on Georges Bank, plus local‐scale ISW generation sites, creates cross‐sea conditions within the water column, resulting in complex ISWs. We find that the background barotropic currents do not significantly influence the ISW spatial distributions, which simplifies the prediction of ISWs; we also consider the influence of tidal currents, general circulation, and stratification. This methodology is potentially useful for additional studies, for example, linking ISWs, energy and nutrient budgets, mixing, and primary production in the Gulf of Maine.

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.

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.

North Atlantic right whale (Eubalaena glacialis) and its food: (I) a spatial climatology of Calanus biomass and potential foraging habitats in Canadian waters

AbstractThis study aimed at identifying potentially suitable foraging habitats for the North Atlantic right whale (NARW; Eubalaena glacialis) in the Gulf of St Lawrence (GSL), on the Scotian Shelf (SS) and in the Bay of Fundy (BoF), Canada, based on the distribution densities of their main prey, Calanus copepod species. More than 4800 historical Calanus spp. water column integrated samples as well as 221 vertically stratified sampling stations were used to create a 3D (latitude, longitude and vertical) climatology of Calanus spp. biomass densities for spring and summer–fall when NARW are feeding in Canadian waters. We then combined this 3D preyscape with bio-energetic considerations to highlight potentially suitable NARW foraging habitats in the region. Our 3D climatological approach successfully identified the known feeding areas of Grand Manan (BoF) and Roseway Basin (western SS), confirming its validity. Expanding our analyses to the GSL and other parts of the SS, we identified in both regions areas previously unknown where Calanus spp. biomass densities exceeded minimum levels suitable for foraging NARW. Our results represent a key contribution to the identification of important foraging areas for NARW in Canadian waters, especially in the context of climate change and the documented shift in NARW distribution.

Long-term studies of lobster abundance at a salmon aquaculture site, eastern Canada

Wild lobster (Homarus americanus) abundance was monitored before, during, and after salmon (Salmo salar) aquaculture production in a bay on Grand Manan Island, New Brunswick, Canada, in an 8-year survey, 2008 to 2015. Diver transects and free-area spot-dives were used to measure the carapace length and determine sex (including berried state) of each lobster encountered both inside (farm) and outside (reference) the lease boundaries. In pairwise comparisons of each sampling date, there was no significant difference between the number of lobsters inside the salmon farming area versus a nearby reference site and no significant difference in the number of berried females inside or out of the farm lease area. Combining data from all lobster surveys (farm and reference sites) indicated an increase over 8 years, similar in slope to the increase of the trap fishery in Lobster Fishing Area (LFA) 38. These results indicate that the fish farm had no obvious impact on lobster density at any point in the salmon production cycle and that inshore lobster abundance followed trends similar to those of the general fishery of LFA 38.

A timely opportunity to protect North Atlantic right whales in Canada

The survival of federally protected North Atlantic right whales (Eubalaena glacialis) requires an immediate reduction in the risk of entanglement in commercial fishing gear. This paper argues that at least a 30% reduction in risk is needed to meaningfully contribute to the conservation of right whales. The argument follows from risk estimates calculated using time and space intersections of right whales and fishing gear in Canadian waters. Almost all the risk occurs during July, August and September (12%, 50%, 37% respectively) and the groundfish fishery contributed the greatest proportion (86%) of annual risk. Given that efforts in the USA to reduce entanglement risk through modified fishing gear have been unsuccessful to date, we address the alternative option of restricting certain fishing gear at times and locations where entanglement risk is elevated. There are many options that Canada could employ to achieve the above risk reduction and our results clearly point to the most effective and efficient action being seasonally restricted fishing in two relatively small regions; the Grand Manan Basin and the Roseway Basin. Fully a third (34%±4%) of the annual risk is associated with these two basins, though fishery catch estimates in the basins are relatively small and declining.

Remnants of Early Mesozoic basalt of the Central Atlantic Magmatic Province in Cape Breton Island, Nova Scotia, Canada

Amygdaloidal basaltic flows of the Ashfield Formation were encountered in two drill holes in areas of positive aeromagnetic anomalies in the Carboniferous River Denys Basin in southwestern Cape Breton Island, Nova Scotia. One sample of medium-grained basalt yielded a plateau age of 201.8 ± 2.0 Ma, similar to the U–Pb and 40Ar/39Ar crystallization ages from basaltic flows and dykes in the Newark Supergroup. A second sample of zeolite-bearing basalt yielded a discordant age spectrum and a younger age of ca. 190 Ma, which is interpreted to date a widespread hydrothermal event related to zeolite formation. Whole-rock chemical data show that the Ashfield Formation basalt is low-Ti continental tholeiite, consistent with its within-plate tectonic setting. Chemically, it resembles basaltic flows in the Mesozoic Fundy and Grand Manan basins exposed in southern Nova Scotia and eastern New Brunswick and elsewhere in Central Atlantic Magmatic Province (CAMP). The age and geochemical data from the Ashfield Formation provide the first evidence for early Mesozoic CAMP volcanism in Cape Breton Island and demonstrate that the event was more widespread in Nova Scotia than previously thought, which has implications for its continuity and extent elsewhere within CAMP.

Proterozoic to Mesozoic evolution of North-West Africa and Peri-Gondwana microplates: Detrital zircon ages from Morocco and Canada

The complex history of assemblage and disruption of continental plates surrounding the Atlantic Ocean is in part recorded by the distribution of detrital zircon ages entrained in continental sedimentary strata from Morocco (Central High Atlas and Argana basins) and Canada (Grand Manan Island, New Brunswick). Here we investigate detrital zircon from the latest Triassic (ca. 202Ma) sedimentary strata directly underlying lava flows of the Central Atlantic magmatic province or interlayered within them. SHRIMP (Sensitive High-Resolution Ion MicroProbe) and LA-ICP-MS (Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry) U–Pb ages for zircon range from Paleozoic to Archean with a dominant Neoproterozoic peak, and significant amounts of ca. 2Ga zircon. These ages suggest a prevailing West African (Gondwanan) provenance at all sampling sites. Notably, the Paleoproterozoic zircon population is particularly abundant in central Morocco, north of the High Atlas chain, suggesting the presence of Eburnean-aged rocks in this part of the country, which is consistent with recent geochronologic data from outcropping rocks. Minor amounts of late Mesoproterozoic and early Neoproterozoic zircon ages (ca. 1.1–0.9Ga) in Moroccan samples are more difficult to interpret. A provenance from Avalonia or Amazonia, as proposed by previous studies is not supported by the age distributions observed here. An involvement of more distal source regions, possibly located in north-eastern Africa (Arabian Nubian Shield) would instead be possible. Paleozoic zircon ages are abundant in the Canadian sample, pointing to a significant contribution from Hercynian aged source rocks. Such a signal is nearly absent in the Moroccan samples, suggesting that zircon-bearing Hercynian granitic rocks of the Moroccan Meseta block were not yet outcropping at ca. 200Ma. The only Moroccan samples that yield Paleozoic zircon ages are those interlayered within the CAMP lavas, suggesting an increased dismantling (i.e. uplift) of the Hercynian chain during emplacement of CAMP lava flows, combined with subsidence of the volcanic grabens.

Peering beneath the Canadian crust

This work was funded by Leverhume Trust research project grant RPG-2013- 332. Equipment was provided by the NERC’s GEF, SEIS-UK: Loan 986. Many thanks to residents of Nova Scotia and New Brunswick for allowing us to install seismometers on their land, and for their interest and hospitality: Ben and Elizabeth Pooley, Calvin and Mary Fraser, Kirk Munn, Mary Guptill and Delbe Comeau, Simeon Comeau, George Klass, Greg McHone and the Grand Manan Museum, Heiner and Alison Josenhans, Bev and Ian Cameron, Maurice Mazerolle, Russell and Debbie Parrott. Thanks to Dalhousie University, Halifax, NS, especially to Mladen Nedimovic, Darlene van de Rijt and Anne Bannon for logistical assistance.

Birds of Brier Island

Brier Island, Nova Scotia, Canada, at the southwestern entrance to the Bay of Fundy, has been known for years as a prime birding destination. It combines access to unusually rich gatherings of pelagic birds, the chance of seeing rarities in greater frequency than almost anywhere else in the province, and the spectacle of large volume land bird migrations. The island lies at the intersection of migratory routes along the east coast of North America. Because of intense oceanic turbulence in the adjacent shallow water, which is in close proximity to deeper water, rich feeding is available for nearshore seabirds and pelagic species. Of the 470+ species recorded from the Province of Nova Scotia as a whole, 355 have been recorded from Brier Island. Many of these are vagrants, mainly of western or southern origin in North America; others are common passage migrants that visit the island briefly in very large numbers, especially in autumn. Apart from possible vagrants in spring and fall, the island is noted for the abundance of passerine migrants in autumn, a striking hawk migration in September and October, late-summer gatherings of phalaropes, shearwaters, and storm petrels, and an abundance of overwintering alcids, loons, grebes, and sea ducks in winter. The island has been the site of bird-banding activity and of Christmas counts for more than 50 years. We provide an introduction to the physiography, geology, physical geography, oceanography, and ecology of the island, along with a list of the breeding birds, a comparison with Grand Manan, New Brunswick, an extensively annotated list of the birds plausibly reported from the island to the middle of 2011, describing occurrence, seasonality, and abundance of all species, and a checklist of the birds of the island. Species occurrence data available via the OBIS Canada data repository http://ipt.iobis.org/obiscanada/resource?r=brierisland_birds

The relative contribution of Saccharina nigripes (Phaeophyceae) to the Bay of Fundy Laminariaceae: spatial and temporal variability

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 543:153-162 (2016) - DOI: https://doi.org/10.3354/meps11566 The relative contribution of Saccharina nigripes (Phaeophyceae) to the Bay of Fundy Laminariaceae: spatial and temporal variability Caroline M. Longtin*, Gary W. Saunders Centre for Environmental and Molecular Algal Research, Department of Biology, University of New Brunswick, Fredericton, NB E3B 5A3, Canada *Corresponding author: longtin.c@gmail.com ABSTRACT: Previous research on the Laminariaceae in the Maritime Provinces of Canada was completed under the assumption that only 2 species, Saccharina latissima (including S. longicruris; simple blade) and Laminaria digitata (digitate blade), were present in the flora. However, the species S. nigripes, which can look morphologically similar to S. latissima and L. digitata, was recently recorded. We used molecular tools to observe how Laminariaceae community composition varied across fetch distances and years and to determine the relative abundance of S. nigripes in the Bay of Fundy intertidal zone. Over 2 years (2010 and 2011) we studied Laminariaceae across a fetch gradient (sheltered to wave-exposed) in 3 regions (Lepreau, Campobello and Grand Manan), with an additional 3 years (2012 to 2014) of data collected from the Lepreau region. Sheltered sites were most similar to each other and were composed of 99% S. latissima. S. nigripes was rare in its simple-bladed morphology, as well as at sheltered sites, and likely does not affect previous literature on S. latissima. Conversely, S. nigripes was the dominant digitate kelp in 2010 and 2011 at moderate and wave-exposed sites; however, it was rare from 2012 to 2014, which may be correlated with increased water temperature. Previous studies on the ecology and distribution of L. digitata in this region may have included S. nigripes in their observations; therefore, further studies on the Laminariaceae in Atlantic Canada must be performed to determine whether the ecology of L. digitata and S. nigripes differ, as S. nigripes is the dominant digitate kelp in certain years. KEY WORDS: Community structure · Intertidal · Kelp · Laminariaceae · Molecular identity · Saccharina nigripes · Wave exposure Full text in pdf format PreviousNextCite this article as: Longtin CM, Saunders GW (2016) The relative contribution of Saccharina nigripes (Phaeophyceae) to the Bay of Fundy Laminariaceae: spatial and temporal variability. Mar Ecol Prog Ser 543:153-162. https://doi.org/10.3354/meps11566 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 543. Online publication date: February 03, 2016 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2016 Inter-Research.