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The eastern coastline of James Bay is known to have been home to sizeable eelgrass beds (Zostera marina L.) which thrived in the bay's shallow, subarctic waters. The region was subjected to substantial hydroelectric dams, large fires, and other human activities in the past half-century. To assess the impact of these factors on eelgrass beds, a historical reconstruction of eelgrass bed distribution was performed from images acquired by Landsat-5 Thematic Mapper (TM) in 1988, 1991, and 1996 and images of the Landsat-8 Operational Land Imager (OLI) in 2019. All the images were classified using the Random Forests classifier (RF) and assessed for accuracy each year on a bay-wide scale using an independent field validation dataset. The validation data were extracted from an eelgrass bed map established using aerial photos and field surveys in 1986, 1991, and 1995 and from a field survey in 2019. The overall validation accuracy of the classified images (between 72% and 85%) showed good agreement with the other datasets for most locations, providing reassurance about the reliability of the research. This makes it possible to use satellite imagery to detect past changes to eelgrass distribution within a bay. The classified images of 1988 and 1996 were also compared to aerial photos taken in years close to each other at ten sites to determine their ability to assess small eelgrass beds' shape and presence. Such a comparison revealed that the classified images accurately portrayed eelgrass distribution even at finer scales. [ABSTRACT FROM AUTHOR]

Canada geese (Branta canadensis) migrating along coastal flyways are reliant on natural coastal ecosystems. Within these stopover sites, eelgrass (Zostera marina), the most common and widespread seagrass species in North America, is an important food resource for migrating waterfowl. Given the growing anthropogenic pressure on coastal ecosystems, geese migrating along coastal regions may find it increasingly difficult to access suitable stopover sites where food is abundant and human disturbance is low. We assessed the influence of hunting and eelgrass on the spatiotemporal distribution of Canada geese in the Tabusintac Bay, New Brunswick, Canada, a wetland of international importance. We surveyed Canada geese at 6 stations from mid‐September to late October, 2016 and 2017. We used 2‐part hurdle models consisting of generalized linear mixed models with binomial and negative binomial response distributions to model Canada geese presence and abundance, respectively, in relation to eelgrass abundance, distance to the mainland coastline, water depth, and tidal conditions in 3 different hunting intensity periods. Eelgrass abundance is a significant predictor of Canada geese presence early in the season, when hunting activity is low. At the onset of the hunting period, geese shifted diurnal distribution to areas farther offshore, indicating a response to avoid disturbance, and the abundance of Canada geese increased with increasing eelgrass availability, emphasizing the importance of eelgrass as a food source during fall migration in that region. Thus, our results highlight the effects of human disturbance and eelgrass abundance in influencing stopover behavior of Canada geese during fall migration in eastern Canada. [ABSTRACT FROM AUTHOR]

Over the last few decades, there has been an increasing recognition for seagrasses' contribution to the functioning of nearshore ecosystems and climate change mitigation. Nevertheless, seagrass ecosystems have been deteriorating globally at an accelerating rate during recent decades. In 2017, research into the condition of eelgrass (Zostera marina) along the eastern coast of James Bay, Canada, was initiated in response to reports of eelgrass decline by the Cree First Nations of Eeyou Istchee. As part of this research, we compiled and analyzed two decades of eelgrass cover data and three decades of eelgrass monitoring data (biomass and density) to detect changes and assess possible environmental drivers. We detected a major decline in eelgrass condition between 1995 and 1999, which encompassed the entire east coast of James Bay. Surveys conducted in 2019 and 2020 indicated limited changes post‐decline, for example, low eelgrass cover (<25%), low aboveground biomass, smaller shoots than before 1995, and marginally low densities persisted at most sites. Overall, the synthesized datasets show a 40% loss of eelgrass meadows with >50% cover in eastern James Bay since 1995, representing the largest scale eelgrass decline documented in eastern Canada since the massive die‐off event that occurred in the 1930s along the North Atlantic coast. Using biomass data collected since 1982, but geographically limited to the sector of the coast near the regulated La Grande River, generalized additive modeling revealed eelgrass meadows are affected by local sea surface temperature, early ice breakup, and higher summer freshwater discharge. Our results caution against assuming subarctic seagrass ecosystems have avoided recent global declines or will benefit from ongoing climate warming. [ABSTRACT FROM AUTHOR]

Numbers of temperate‐breeding Atlantic and Mississippi Flyway Canada geese have greatly increased since the 1980s. Consequently, numbers of yearlings, sub‐adults and failed breeders undertaking pre‐molt migration to northern latitudes has also increased, potentially providing additional hunting opportunities for Cree hunters living near James Bay, Canada. We described movement patterns and habitat use of molt migrant Canada geese Brenta canadensis maxima along the east coast of James Bay based on nine geese fitted with GSM–GPS devices during 11 northward and eight southward migrations between 2015 and 2019. Geese staged for 2.8 ± 0.6 days (mean ± standard error of the mean) at 3.2 ± 0.6 staging sites (mostly tidal flats and salt marshes) from the first week of June in spring and 3.8 ± 1.8 days at 2.0 ± 0.5 staging sites (mostly inland freshwater wetlands, peatlands and tidal flats) from the first week of September when returning south. Shallow and deep water habitats were used as resting sites during both migrations. In spring, molt migrants were mostly harvested in June well after the migration of sub‐arctic breeding geese whereas in autumn, both subspecies were harvested in September. Molt migrant temperate‐breeding geese can increase harvest opportunities and represent supplementary wildlife food for Cree communities. However, the current number of molt migrant geese harvested by Cree hunters is not sufficient to significantly impact populations of temperate‐breeding geese. [ABSTRACT FROM AUTHOR]

An in-depth understanding of the response of wood under compression/densification calls for characterization of strain distribution over the wood. Recently, an image processing technique has been used for strain evaluation on wood, as the traditional devices are not able to measure irregularly distributed strain field. Unfortunately, the classic image correlation algorithm is rather time consuming and could take up to days to compute the final result. In this paper, an improved image correlation algorithm with linearly changed searching region during the correlation seeking is presented. The processing speed is increased by over 1800 times while keeping the high accuracy of the displacement measurement. In addition, full feasibility tests were conducted on balsam fir (Abies balsamea (L.) Mill.) and eastern white pine (Pinus strobus L.) samples.The results demonstrate the high robustness, efficiency, and accuracy of the proposed method. Une connaissance approfondie de la reaction du bois soumis a la compression ou a la densification exige la carac-terisation de la distribution des tensions dans le bois. La technique de traitement des images a recemment ete utilisee pour evaluer les tensions dans le bois etant donne que les appareils traditionnels ne sont pas capables de mesurer un champ de tension distribue de facon irreguliere. Malheureusement, l'algorithme classique de correlation des images demande passable-ment de temps et pourrait prendre plusieurs jours pour calculer le resultat final. Dans cet article, nous presentons un algo-rithme de correlation d'images ameliore avec une zone de recherche lineairement modifiee pendant la recherche de correlations. La vitesse de traitement est 1 800 fois plus rapide tout en conservant la precision elevee de la mesure des de-placements. De plus, des tests complets de faisabilite ont ete realises sur des echantillons de sapin baumier (Abies balsamea (L.) Mill.) et de pin blanc (Pinus strobus L.). Les resultats demontrent que la methode proposee est tres robuste, efficace et precise. [Traduit par la Redaction], Introduction Recently, wood densification has attracted the attention of researchers (Wang and Cooper 2005; Gong et al. 2006). This technology allows utilization in new applications of wood from some fast-growing [...]

In several processes of the forest products industry, an in-depth knowledge of log and board internal features is required and their determination needs fast scanning systems. One of the possible technologies is X-ray computed tomography (CT) technology. Our paper reviews applications of this technology in wood density measurements, in wood moisture content monitoring, and in locating internal log features that include pith, sapwood, heartwood, knots, and other defects. Annual growth ring measurements are more problematic to be detected on CT images because of the low spatial resolution of the images used. For log feature identification, our review shows that the feed-forward back-propagation artificial neural net-work is the most efficient CT image processing method. There are also some studies attempting to reconstruct three-dimensional log or board images from two-dimensional CT images. Several industrial prototypes have been developed because medical CT scanners were shown to be inappropriate for the wood industry. Because of the high cost of X-ray CT scanner equipment, other types of inexpensive sensors should also be investigated, such as electric resistivity tomography and micro-waves. It also appears that the best approach uses various different sensors, each of them having its own strengths and weak-nesses. Plusieurs processus de l'industrie des produits forestiers exigent une connaissance approfondie des caracteristiques internes des billes et des planches dont l'acquisition necessite des appareils a balayage rapide. Une des technologies potentielles est la tomodensitometrie (TDM). Notre article passe en revue les applications de cette technologie pour mesurer la densite du bois, faire le suivi de la teneur en humidite dans le bois et localiser les caracteristiques internes du bois, telles que la moelle, le bois d'aubier, le bois de coeur, les noeuds et les autres defauts. Il est plus difficile de mesurer les cernes annuels sur les images obtenues par TDM a cause de la faible resolution spatiale de ces images. Pour l'identification des caracteristiques des billes, notre revue montre que le reseau neuronal artificiel multicouche a retropropagation est la methode la plus efficace pour traiter les images obtenues par TDM. Il y a aussi certaines etudes qui tentent de reconstruire des images en trois dimensions a partir des images en deux dimensions obtenues par TDM. Plusieurs prototypes industriels ont ete developpes parce qu'il a ete demontre que les tomographes medicaux ne sont pas appropries pour l'industrie du bois. Etant donne le cout eleve des appareils de TDM, d'autres types de capteurs bon marche devraient etre etudies, tels que la tomo-graphie de resistivite electrique et les micro-ondes. Il semble aussi que la meilleure approche consiste a utiliser plusieurs capteurs differents, chacun ayant ses forces et ses faiblesses. [Traduit par la Redaction], Introduction In current wood manufacturing operations, knowledge of wood characteristics and measurement of those characteristics are essential to ensure that the right fibre is directed to the appropriate wood manufacturing [...]

Atlantic Brant (Branta bernicla hrota) is an Arctic-breeding migratory waterfowl that relies heavily on Common Eelgrass (Zostera marina) for food during migration and overwintering. Although the abundance of Atlantic Brant along the coasts of the Maritime provinces has declined drastically over the past decades, some flocks continue to migrate through the area in spring. Here, we present field observations of Atlantic Brant spring staging in the Tabusintac Bay, New Brunswick, Canada. We surveyed the Tabusintac Bay seven times between 26 May and 6 June 2018. We observed a maximum daily count of 1259 individuals, which is comparable to high counts from the 1970s. These spring surveys indicate the continuing importance of Tabusintac Bay to Atlantic Brant for spring staging. There is a pressing need to increase monitoring and research in the region and to preserve or enhance the quality of the area for spring staging brant. [ABSTRACT FROM AUTHOR]