NSIS Volume 47, Part 2
Permanent URI for this collectionhttps://hdl.handle.net/10222/71043
Browse
Recent Submissions
Item Open Access End Matter(Nova Scotian Institute of Science, 2013)Item Open Access Editorial Board listing(Nova Scotian Institute of Science, 2013)Item Open Access Voyage of Discovery: Fifty Years of Marine Research at Canada’s Bedford Institute of Oceanography(Nova Scotian Institute of Science, 2013)Announcement of the forthcoming publication of Voyage of Discovery Fifty Years of Marine Research at Canada’s Bedford Institute of Oceanography, edited by D.N. Nettleship, D.C. Gordon, C.F.M. Lewis and M.P. Latremouille.Item Open Access Changes to the Publication of the PNSIS October 2013(Nova Scotian Institute of Science, 2013)News from the NSIS LibrarianItem Open Access Council Reports NSIS AGM(Nova Scotian Institute of Science, 2013) Nova Scotian Institute of ScienceItem Open Access Age-Related Changes in Motor Ability and Motor Learning in Triple Transgenic (3×TG-AD) and Control (B6129SF1/J) Mice on the Accelerating Rotarod(Nova Scotian Institute of Science, 2013) Oore, Jonathan J.; Fraser, Leanne M.; Brown, Richard E.Mouse models of Alzheimer’s disease (AD) show both cognitive and neuromotor impairments. We measured motor ability and motor learning of male and female triple transgenic (3×Tg-AD) and control (B6129SF1/J) mice on the accelerating Rotarod in a cross-sectional design at 2, 6, 9, 12, and 15 months of age. At all ages except for 2 months, transgenic mice performed better and had a steeper motor learning curve than controls. Female mice showed better motor performance than males, while males had a steeper learning curve than females. Age did not have a significant main effect on Rotarod performance. However, age and genotype showed an interaction, where the performance of 3×Tg-AD mice peaked at 6 months of age and decreased as age increased. The performance of controls was below that of 3×Tg-AD mice at each age. Behavioural differences seen in the 3×Tg-AD mice may help us to understand the development of neuromotor dysfunction in AD.Item Open Access First Verified Record for Shortnose Sturgeon, Acipenser brevirostrum LeSueur, 1818, in Minas Basin, Bay of Fundy, Nova Scotia, Canada(Nova Scotian Institute of Science, 2013) Dadswell, Michael J.; Nau, George; Stokesbury, Michael J.W.A shortnose sturgeon was caught in fisherman Wayne Linkletter’s intertidal fish weir in Minas Basin near Economy, Nova Scotia, on June 29, 2013. It was an adult, 73.7 cm fork length and weighed ~4.5 kg. Fishers in Minas Basin relate that they have captured shortnose sturgeons in their weirs in the past decade (1 or 2 fish/y) but this is the first sighting verified by photographic evidence. In Canada shortnose sturgeons were previously known only from the Saint John River and Harbour. The new record extends the coastal range of the species by approximately 165 km and is a new addition to the fish fauna of Nova Scotia.Item Open Access The Fishery for Speckled Trout, Salvelinus fontinalis, Over a 28-Year Period in the Tangier Grand Lake Wilderness Area, Nova Scotia(Nova Scotian Institute of Science, 2013) MacMillan, John L.; Madden, Reginald J.; Wilson, Tamara; Kenney, MeganThe Tangier Grand Lake Wilderness Area (16,000 ha) is located about 100km east of Halifax, Nova Scotia, and supports a popular fishery for speckled trout. The purpose of this study was to assess the status of the trout fishery and address concerns related to over-exploitation. Angler check points were occupied during 1979 and 2007 on an access road to sample the catch of anglers during the May-June period of heavy angler activity. In 1979, a total of 1380 interviewed anglers spent 6889 hours to catch 1852 trout. In comparison, a total of 178 interviewed anglers spent 1363 hours to catch 593 trout during 2007. The differences associated with sample size between survey years reflect sub-sampling in 2007 rather than a change in angler activity. The majority of anglers retained less than three trout and of the total trout caught, anglers released 19% in 1979 and 50% in 2007. Catch per hour, size, age, and growth rate of trout were similar between surveys. Results indicated that there was little change in this fishery between the 28 years separating the two creel surveys.Item Open Access A Scanning Electron Microscope Analysis of Morphogenesis and Embryos and Juveniles of the Direct Developing Isopod, Cyathura polita (Stimpson, 1855)(Nova Scotian Institute of Science, 2013) Mercer, Sara C.; Dadswell, Michael J.; Gibson, Glenys D.Isopods are a species rich, morphologically diverse group characterised by direct development of young within a marsupium. Collectively, these traits make isopods excellent models for understanding the changes to morphogenesis that occur in the evolution of direct development, but the overall understanding of this process is limited by a lack of comparative data. We investigated morphogenesis in Cyathura polita, an isopod common in estuaries along the Atlantic coast of North America, from gastrulation to release of young as benthic juveniles, using Scanning Electron Microscopy. We found that early development of C. polita from gastrulation to hatching from the extraembryonic membranes was generally similar to that described by earlier work using sectioned material, but found that development through the manca stage to free living juveniles differed from previous studies. For instance, the embryonic dorsal organ differed from that described generally for isopods as the apical surface is covered by a sieve plate and the typically reported microvilli were not observed. Differences in timing were also noted: for example, segments appeared throughout the pereon and pleon well before the post-naupliar appendages, and not coincident with them as described previously for isopods. Limb development occurred simultaneously except that pereopod 7 did not form until the post-manca stages, as is typical for this group, suggesting there is non sequential (or suppression of) teloblast activity in postnaupliar development. Also, some broods contained young of different developmental stages (i.e., early embryos and late manca), indicating that spawning events are repeated and overlap, which is perhaps adaptive in the shortened reproductive season characteristic of our study population that is at the northern limit of the known range for this species. Mean brood size was 53.2 ± 18.9 young (range 4-108), the largest reported for Anthuridae (a family of isopod crustaceans).Item Open Access Coronilla varia L. (Fabaceae): An Invader of a Coastal Barrier Beach in Nova Scotia, Canada(Nova Scotian Institute of Science, 2013) Flynn, Andrea; Miller, Anthony G.; Garbary, David J.Coronilla varia L. (crown vetch) is described as an invasive plant on a coastal sand dune system (Mahoneys Beach) in Nova Scotia facing the southern Gulf of St. Lawrence. This is the first time that C. varia has been shown as invasive in Atlantic Canada, and the first time it has been characterized as invasive on coastal sand dunes. Accordingly, colonies of C. varia forming more than 90% of the plant cover occupy 8% of the total dune system and account for 32% of the area in the vegetation zone where C. varia has become abundant. C. varia can achieve high percentage cover, with all of the major dune plants, i.e., Ammophila breviligulata, Lathyrus japonicus, Toxicodendron radicans and Myrica pensylvanica. Where C. varia achieves maximum abundance (i.e., >80% cover and ca. 200 shoots m2), it has seemingly replaced A. breviligulata and L. japonicus. We do not know when C. varia first colonized Mahoneys Beach, but conspicuous colonies were recorded there by 2005, and a colony was found on the adjacent dune system (Dunns Beach) for the first time in 2010.Item Open Access Early Spring Flowering in Nova Scotia: An Extreme Spring is Reflected in Advanced Flowering(Nova Scotian Institute of Science, 2013) Hill, Nicholas M.; Garbary, David J.Twenty species of herbaceous plants and four non-amentiferous shrubs were found in flower in March-April in Nova Scotia during the spring of 2012. Plants were observed primarily in Kings and Antigonish Counties, with several observations from Inverness County. The precocious flowering is attributed to an abnormally warm late winter and spring (February-March) in which climate normals for monthly average temperature were exceeded by a minimum of 1.2°C in February (Tracadie) to a maximum of 8.5°C in March (Kentville). Flowering was an average of 17 days earlier than herbarium records in the largest regional herbaria (ACAD, NSAC). Proportional contribution to the early flowering guild was greater for exotic species which featured weedy families not represented in the native group. These observations of spring climate conditions and flowering phenology are consistent with regional climate change associated with milder and earlier springs.Item Open Access Editorial: Supporting Science in Canada(Nova Scotian Institute of Science, 2013) Wells, Peter G.