David J. Garbary- PhD
- St. Francis Xavier University
David J. Garbary
- PhD
- St. Francis Xavier University
About
244
Publications
81,239
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Introduction
Skills and Expertise
Current institution
Additional affiliations
September 1978 - July 1984
Position
- Research Associate, URF
Description
- Herbarium Botanist and NSERC University Research Fellow
August 1984 - present
Description
- Faculty member in a Biology Department of twelve at an institution that is mostly dedicated to undergraduate teaching and with limited graduate programs (e.g., MSc in Biology).
Education
September 1975 - September 1978
Publications
Publications (244)
Greenhouse gas (GHG) emissions (CO2, CH4, N2O) were measured in the two years prior to, and the year of, the hydrological restoration of the ditched Big Meadow Bog (BMB). The total greenhouse gas emission from the south of BMB in recovery succession after abandonment of the area by nesting Herring Gulls 20 years earlier (‘BMB Recovering’) was twice...
The endangered plant Geum peckii has found refuge on Brier Island, but is likely being put in peril by significant climate change. We evaluated climate change since the 1960s in the context of regional atmospheric and oceanic influences. On the outer southern edge of the Bay of Fundy, Brier Island sits in an ocean hotspot that has warmed at least 2...
The ecology of the Eastern Mountain Avens (Geum peckii), Endangered in Canada and Imperiled globally, was examined on Brier Island, Nova Scotia, to inform its conservation management and prospect for long-term survival in situ in Canada. Over ten years of study, a picture emerged of a plant adapted to growth in naturally stressed wetland habitats w...
The red alga Choreocolax polysiphoniae is part of a complex marine symbiotum involving at least seven species from four eukaryotic phyla. The red alga C. polysiphoniae is an obligate parasite on another red alga, Vertebrata lanosa, that, in turn, is an obligate epiphyte on the ultimate host, the brown macroalga A. nodosum. For the first time, popul...
An analysis of temperature in Nova Scotia, using climate normals for 1961-1990 and temperature records from 1961 to 2020, is presented for 16 sites across the province. These records show a slight warming trend in the first 40 years from 6.0 ± 0.5 °C (1961-1990), followed by a more significant increase in average temperature post-1990 of 1.0 °C to...
The distribution and ecology of the invasive brown alga Fucus serratus along the 500 km Atlantic coast of Nova Scotia, Canada, has been poorly explored. We observed significant intertidal penetration at four sites in the southwestern part of the province, and then examined numerous sites along the Atlantic coast of Nova Scotia. Surveys of attached...
Marine plants control the accumulation of biofouling organisms (epibionts) on their surfaces by various chemical and physical means. Ascophyllum nodosum is a perennial multicellular brown alga known to shed patches of epidermal material, thus removing epibionts and exposing unfouled surfaces to another cycle of colonization. While surface shedding...
Vanadium-dependent haloperoxidases (V-HPO) are specific enzymes involved in the metabolism of reactive oxygen species in marine algae. These enzymes contribute to early embryogenesis of algae in the order Fucales, catalyzing the reactions which result in phlorotannin incorporation into the newly forming zygote cell wall and adhesive material. In th...
The tetrasporophytic ‘Trailliella’ stage of the red algal genus Bonnemaisonia is reported for the first time from the Southern Hemisphere. Here we describe a bloom of the tetrasporophyte of B. hamifera from the mouth of the Waikouaiti River, Karitāne, South Island, where it occurred as thousands of free-floating tufts up to 1 cm wide in shallow wat...
From May to October 2017 seaweeds were identified in the field and laboratory from 20 sites around Brier Island, Nova Scotia. While most sites were intertidal rocky shores, there were one small salt marsh and one eelgrass bed included in the study, and some subtidal sampling was conducted utilizing SCUBA and snorkeling. The Brier Island seaweeds co...
The origin and early diversification of land plants is one of the major unresolved problems in evolutionary biology. Occurring nearly half a billion years ago, the transmigration of green organisms to land changed the landscape and provided the food source for terrestrial life to invade a vast uninhabited space, adapt and radiate. Although bryophyt...
On Brier Island in eastern Canada, ditching of Big Meadow Bog resulted in predictable shifts in the plant community as shrubs and trees proliferated across the drained landscape. The attraction of nesting gulls to the ditched bog and their daily foraging at distant mink farms was not predictable. To better understand the impacts of the nesting gull...
On Brier Island in eastern Canada, ditching of Big Meadow Bog resulted in predictable shifts in the plant community as shrubs and trees proliferated across the drained landscape. An unpredictable result, the attraction of the ditched bog to nesting gulls that daily foraged 35 km away at nutrient-enriched mink farms, caused larger impacts. Disruptio...
Irish moss (Chondrus crispus Stackhouse) is a red alga that is common in Atlantic Canada. A unique strain of this species, the giant Irish moss, grows in a single location and is under strict protection. Unlike the common coastal form, the giant Irish moss reproduces solely by fragmentation and is found in gametophyte form. A 99.9% decline in giant...
A simple method to assess climate warming is described, which is suitable for post-secondary classes in environmental sciences. This method is based on climate normals and subsequent weather data, and is demonstrated using Government of Canada archived climate/weather data from sites in Prince Edward Island including Charlottetown Airport, Alliston...
Ascophyllum nodosum is commercially harvested in the southwestern parts of Nova Scotia. Here the hypothesis is evaluated that harvesting results in a reduction in the abundance of Vertebrata lanosa, an obligate epiphyte of A. nodosum. Sampling at 10 harvested and 16 non-harvested sites showed that percent cover and frequency were significantly lowe...
The local distribution of Prasiola crispa is reported for the first time in Nova Scotia. It was common on emergent basalt outcrops in a coastal wetland on the Bay of Fundy shores of Brier Island. The alga was present on 19 of 102 basalt outcrops in one of the breeding colonies of the Herring Gull, Larus argentatus, and was only associated with basa...
Ascophyllum nodosum provides the ultimate host for a symbiotic community of diverse eukaryotes comprising two brown algae (Ascophyllum nodosum, Elachista fucicola), two red algae (Vertebrata lanosa, Choreocolax polysiphoniae), a fungus (Mycophycias ascophylli), an insect (Halocladius variabilis), and a diatom (Navicula endophytica). The interaction...
Halat et al. (2015. Phycologia 54: 599-608) concluded that the commercial harvest of Ascophyllum nodosum in Nova Scotia resulted in a detrital deficit amounting to over 100% of the harvest biomass. Here we respond to Ugarte et al. (2017. Phycologia 57: 114-115) that our estimate was exaggerated. We reaffirm our conclusions that: (1) epidermal shedd...
- Phylometabolomics can be performed by either NMR or UPLC-MS-QTOF by exporting data to open source algorithms - NMR +’s for this study: minimal sample prep, reproducible multi-site analysis, scalable, non-destructive sampling - UPLC-MS-QTOF +’s for this study: separation, fast carbon count/elemental composition with smaller quantities of scarce me...
Metabolomics methods used to determine taxonomic identity and quality control of natural health product/dietary supplements were compared using a “model” collection of 42 Vaccinium L. species with international origins. Ultra performance liquid chromatography-mass spectrometry-quadrupole time of flight (UPLC-MS-QTOF) and nuclear magnetic resonance...
Epidermal shedding, a process that effectively controls epiphyte accumulation on certain long-lived macroalgae, was quantified weekly for over 1 year in a population of Ascophyllum nodosum from Nova Scotia. About 25% of the frond epidermis is shed per week and for at least 9 months of the year, this shedding occurred in population-level cycles of s...
To investigate the illuminance requirements for the culture of red algae in finfish effluent, both Chondrus crispus and Palmaria palmata were assessed simultaneously at three irradiances. Apical tips, 3.5 cm length, were stocked at 2 g L−1 in 1-L glass flasks with enriched seawater in two 24-day experiments, at 10 and 14 °C, respectively. Palmaria...
Vertebrata lanosa is an abundant and obligate red algal epiphyte of Ascophyllum nodosum that forms part of a complex and highly integrated symbiotic system that includes the ascomycete, Mycophycias ascophylli. As part of ongoing studies to resolve interactions among species in the symbiosis, we used pulse amplitude modulation fluorimetry of chlorop...
In development since 1996, AlgaeBase (http://www.algaebase.org) is an on-line database providing free access to authoritative taxonomic, distributional and nomenclatural information of more than 135,000 names of species and infraspecific taxa of algae set in the context of a taxonomic hierarchy. The project was initially funded by the Higher Educat...
Palmaria palmata was integrated with Atlantic halibut Hippoglossus hippoglossus on a commercial farm for one year starting in November, with a temperature range of 0.4 to 19.1°C. The seaweed was grown in nine plastic mesh cages (each 1.25 m 3 volume) suspended in a concrete sump tank (46 m 3) in each of three recirculating systems. Two tanks receiv...
The high cost of aeration needed to tumble culture macroalgae is a limiting factor for integration with land-based finfish culture. Toward reducing this electricity cost, we compared intermittent aeration (16 h on:8 h off) with continuous aeration (24 h on) on the productivity of two strains of Chondrus crispus (Basin Head and Charlesville) and Pal...
In 2001–2002, there were severe declines of eelgrass (Zostera marina) in estuaries along the Nova Scotia coast of the southern Gulf of St. Lawrence. We examined the relationship between the recent invasion of European green crabs (Carcinus maenas) and the eelgrass decline in Benoit Cove in Tracadie Harbour. The abnormally abundant eelgrass wrack co...
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 (Febr...
CCoronilla 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, c...
Carrot side-trimming opens the carrot canopy, permitting greater sunlight penetration and airflow. This reduces moisture build-up and creates unfavorable conditions for the development of common carrot pathogens such as Sclerotinia sclerotiorurn (Lib.) de Bary. This study was carried out during the 2008 and 2009 growing seasons and was the first to...
Palmaria palmata and Chondrus crispus were grown for 4 weeks in 1-L flasks at 10 °C to evaluate nutrient uptake and their potential application as nutrient biofilters in effluent from finfish culture. For greatest bioremediation benefit within an integrated system, we conclude that a seaweed biofilter using these species should be placed prior to b...
During August and September 2010, we surveyed the entire 20.4 km perimeter of Brier Island, Nova Scotia, for the invasive shrub Rosa rugosa (Rugosa Rose). This island in the outer reaches of the Bay of Fundy of Nova Scotia is geographically isolated and relatively undeveloped. Our objective was to determine the extent and mechanism of the invasion...
The marine algal flora of the Keret Archipelago ( N, E) in the White Sea, Russia was investigated during 2008. Over 250 algal records from more than 15 islands and several sites on the adjoining mainland produced a total of 62 algal species. This raised the total from 56 to 88 species of Chlorophyta (23 species), Phaeophyceae (31 species), Rhodophy...
The physiological ecology of Prasiola stipitata was examined in situ from two supralittoral sites in the Bay of Fundy (Nova Scotian, Canada) during November 2011, when the population was undergoing major expansion. Photosynthetic parameters (effective quantum yield, ΦPSII, maximum quantum yield, Fv/Fm, and relative electron transport rate, rETR) we...
Vertebrata lanosa is an abundant and obligate red algal epiphyte of Ascophyllum nodosum that forms part of a complex and highly integrated symbiotic system that includes the ascomycete, Mycophycias ascophylli. As part of ongoing studies to resolve interactions among species in the symbiosis, we used pulse amplitude modulation fluorimetry of chlorop...
Larvae of the Holarctic marine chironomid, Halocladius variabilis (Staeger), have strong fidelity to the tuft-forming brown alga, Elachista fucicola (Velley) Areschoug, an abundant epiphyte on intertidal fucoids of the North Atlantic. We show that larvae are sufficiently motile to select an algal host in a Petri dish within 3-4 cm, and that larvae...
Intact phycobilisomes from a wild-type red Chondrus crispus and its vegetatively derived green mutant were isolated by centrifugation through a discontinuous sucrose density gradient. Pigment composition was subsequently characterized by spectrophotometry. Vegetative thalli of the two strains grown together for six months in the laboratory resulted...
While a variety of plant hormones from brown algae were described, there were few studies that examined the combined effects of these hormones on morphogenesis and photosynthetic physiology in developing fucoid embryos. We evaluated the effects of phytohormones to determine the extent, to which responses were similar to those of terrestrial plants....
We consider design in multicellular organisms from the perspective of environmental and internal constraints on body architecture. The significance of modularity (i.e., the sequential addition of iterative units), which dominates plant development, is assessed in relation to the fractal dimensions of plants, motile and sessile metazoans, and macroa...
The reproductive cycle of the black crowberry (Empetrum nigrum L., Ericaceae) was investigated on exposed headlands on the Atlantic coast of Nova Scotia. At the main study site, Gaff Point, aerial photographs revealed a shoreline retreat rate from 1976 to 2011 (ca. 0.3 m·y–1), with a threefold increase in the rate of heath area loss in the last 10...
To evaluate the nutrient removal capabilities of two red macroalgae, apical blades were cultured in the lab for 4 weeks at either 6, 10, or 17°C and nitrate at either 30 or 300 μM, typical of the seasonal range of conditions at a land-based Atlantic halibut farm. Stocking density was 2.0 g L−1, irradiance 125 μmol photons m−2 s−1, photoperiod 16:8...
Population ecology of Palmaria palmata is described from the intertidal zone of Digby Neck and adjacent islands of Nova Scotia. The primary objectives were: to evaluate the difference in habitat specialization and population structure of P. palmata between harvest and non-harvest shores, and to characterize differences in thallus structure and fron...
A mathematical model of the commercial harvest of Palmaria palmata (Dulse) is presented based on a logistic model and field data collected on Digby Neck, Nova Scotia from 14 harvested shores during May to August, 2010. Field observations used to estimate model parameters included cover of Dulse before and after harvest from Dulse dominated boulders...
Germanium dioxide (GeO2) has been used for many years in the cultivation of red and green algae as a means of controlling the growth of diatoms. Brown algae are sensitive to GeO2, however, the basis of this sensitivity has not been characterized. Here we use embryos of Fucus vesiculosus to investigate morphological and physiological impacts of GeO2...
Increasing moss pressures have been observed in wild blueberry fields, which have been attributed to increased precipitation, reliance of fertilizers to provide adequate yield potential, and increasing soil organic matter content. This has coincided with uncertainty regarding the distribution and diversity of mosses present in fields, the competiti...
Over 1400 flowering records of 135 species were recorded from over 125 visits to more than 20 sites in Antigonish County, Nova Scotia from November 2005 to January 2006, when the growing season is normally over. The species identified were primarily herbaceous dicots; however, there were four species of woody plants (Cornus sericea, Spiraea latifol...
Phenotypic plasticity was examined in the economically and ecologically important brown alga Ascophyllum nodosum in southwestern Nova Scotia, considering specifically how nutrient loading affected its vegetative and reproductive features. To determine this, we examined morphometric changes in A. nodosum from two sites receiving direct effluent impa...
Forest herbs account for greater species richness than any other plant type in deciduous forests and are the most vulnerable to anthropogenic disturbances. We examined whether the limited distribution of rare Appalachian forest herbs in Nova Scotia is related to edaphic specialization or a history of anthropogenic disturbance. Remnant populations a...
The ribbed mussel, Geukensia demissa, is highly dependent on the cordgrass Spartina alterniflora for amelioration from environmental stress and substrate stabilization. Spartina alterniflora is a foundation species in marshes, and G. demissa is typically associated with cordgrass beds. Marshes in the southern Gulf of St. Lawrence are experiencing e...
Phylogenetic relationships of the fungal symbiont of two brown algae were evaluated in the context of host diversity using ribosomal large subunit (nuLSU) sequences. Phylogenetic analysis indicates that Mycophycias ascophylli (phycobionts Ascophyllum nodosum, Pelvetia canaliculata) is misclassified in Verrucariales (Eurotiomycetes). There was no ev...
Thirty populations of Chondrus crispus Stackhouse from Nova Scotia were collected during the years 1993 to 2011. Taken from estuaries, wave exposed open coasts, high intertidal rock pools and shallow subtidal habitats, the populations were evaluated for relative abundance of tetrasporophytic and gametophytic life history phases. Over 2,800 thalli w...
We examined gametes, syngamy, and zygote formation in Prasiola meridionalis Setchell & Gardner and Rosenvingiella constricta (S. & G.) Silva with the transmission electron microscope. We compare the structures we observed with those of the Atlantic species P. stipitata Suhr and describe some previously unreported features. The sperm possessed a num...
Reciprocal crosses between male and female gametes of Ascophyllum nodosum (L.) LeJolis and Fucus vesiculosus L. were made from plants collected at Tor Bay, Nova Scotia. Crosses within each species were viable and resulted in normal zygote development. Hybrids occurred in low frequency in the cultures (ca. 1–5%) and developed either an initial rhizo...
The spermatozoid of Lycopodiella lateralis (R. Br.) B. Øllgaard is ovoid and biflagellated and contains little cytoplasm. A large, rounded, condensed nucleus occupies the central region of the cell. At the rear of the cell is a cluster of starch-containing plastids associated with numerous elongated mitochondria and small pockets of remnant cytopla...
Forest herbs account for greater species richness than any other plant type in deciduous forests and are the most vulnerable to anthropogenic disturbances. We examined whether the limited distribution of rare Appalachian forest herbs in Nova Scotia is related to edaphic specialization or a history of anthropogenic disturbance. Remnant populations a...
The underlying physiology of algal antioxidant compounds is reviewed in the context of seaweed biology and utilization. The application of seaweed antioxidants in foods, food supplements, nutraceuticals and medicine is considered from the perspective of benefits to human health. We advocate that direct consumption of seaweed products for their anti...
Territorial sea data is from L. Pruett and J. Cimino, unpublished data, Global Maritime Boundaries Database (GMBD), Veridian - MRJ Technology Solutions, (Fairfax, Virginia, January, 2000) (excluding Caspian sea and 2,867,050 km2 of disputed territorial). Territorial Sea is defined under the United Nations Convention on the Law of the Sea (UNCLOS) a...
Coastal length data are based on the World Vector Shoreline, United States Defense Mapping Agency, 1989. Figures were calculated by L. Pruett and J. Cimino, unpublished data, Global Maritime Boundaries Database (GMBD), Veridian - MRJ Technology Solutions, (Fairfax, Virginia, January, 2000).
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Numbers of marine zooplankton by family and species.
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Occurrence, status, and demographic trends of species and populations of marine mammals (Eastern Canada, Canadian Arctic, and Western Canada provinces).
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Abstract in French - Résumé en français. French translation of the abstract by Philippe Archambault.
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Evaluating and understanding biodiversity in marine ecosystems are both necessary and challenging for conservation. This paper compiles and summarizes current knowledge of the diversity of marine taxa in Canada's three oceans while recognizing that this compilation is incomplete and will change in the future. That Canada has the longest coastline i...
Rosa rugosa is described for the first time as an invasive species associated with coastal sand dunes in Atlantic Canada. Our surveys of 24 beaches on western Cape Breton Island and the mainland of northern Nova Scotia from Cheticamp to Fox Harbour showed that 11 of the dune systems (ca. 45%) were colonized. This was more prevalent in Cape Breton w...
The green algal genus Basicladia W. E. Hoffman & Tilden suggested for synonymy in Cladophora Kutz. by van den Hoek is reconfirmed as a genus based on the distinct basal system and the primarily opizoic habit associated with freshwater turtles. Previously assigned to Cladophora sect. Basic ladia (W. E. Hoffmann & Tilden) C. Hoek, C. Kosterae C. Hoek...
Fluorescence and electron microscopy were used to examine epidermal shedding in the fucoid alga, Ascophyllum nodosum. Mature meristoderm cells are ca. 50-100 x 30-40 and highly polarized, with a single nucleus and chloroplasts near the base of the cell. Nuclei in these cells undergo mitosis when they are dividing to form a new cortical cell towards...
The commensal (and possibly mutualistic) symbiosis between the marine chironomid, Halocladius variabilis, and brown algal epiphytes of Fucus vesiculosus and Ascophyllum nodosum is described for the first time from Europe, based on field studies from the White Sea, Russia. While the primary host, Elachista fucicola, and the secondary host, A. nodosu...
Sporocladopsis jackii is a new species of green seaweed from eastern Canada and Maine. The species is abundant in late summer and is a conspicuous part of the epizoic flora on living shells of the mud snail, Ilyanassa obsoleta. The alga comprises a densely packed, branched filamentous base from which arise numerous unbranched to sparsely branched e...
Understanding epiphyte distribution in coastal communities is important because these organisms affect many others directly or indirectly. Yet, their distribution has been considerably less studied than that of their hosts and other primary-space holders. Identifying major sources of variation in epiphyte abundance is thus still a need. Environment...
![Fig. 5. Typical rate of decline of [O 2 ] 1 mm to 3 mm below the...](profile/Barry-Taylor-5/publication/233684898/figure/fig5/AS:668946214703117@1536500614759/Typical-rate-of-decline-of-O-2-1-mm-to-3-mm-below-the-surface-of-a-Leptomitus-lacteus_Q320.jpg)
The water mould Leptomitus lacteus bloomed in a small stream in northern Nova Scotia, Canada, for at least four months from December through March when water temperatures were near 0 °C and the stream was frequently ice-covered. The bloom occupied much of the substratum along
1.5 km of stream below the effluent outfall from a composting facility. A...
Imaging-PAM fluorometry was used to assess the chlorophyll a fluorescence parameter (effective quantum yield) in Frcus vesiculosus. F. disttchus. ssp. distichus and AscophyIIum nodosum. The objective was to show variadon in fluorescence yield associated with age and frond organ, and to illustrate the spatial scales at which photosynthetic parameter...
We studied the population ecology and productivity of the little-known marine insect Halocladius variabilis (Chironomidae) from the exposed rocky intertidal zone on the Atlantic coast of Nova Scotia, Canada. Larvae of H. variabilis are host-specific symbionts of the brown alga Elachista fucicola, which in turn is an abundant epiphyte on the dominan...
Five moss species were found in the high intertidal zone of salt marshes in Nova Scotia, eastern Canada. This is the first report of bryophytes from salt marshes from North America. In each of the salt marshes where mosses occurred, one to three moss species occurred in monospecific or mixed species assemblages. Campylium stellatum and Bryum capill...
Red algal systematics is in a state of flux unparalleled since the early decades of this century. Ultrastructural and biochemical studies are providing features for a revised classification at ordinal and supraordinal ranks, whereas characters of vegetative and reproductive morphology continue to establish discontinuities among taxa at lower ranks....
Questions
Question (1)
While there are lots of examples of diminutive males (e.g., fish, barnacles, spiders), the only examples I know with diminutive females are from the red algae where it is the common life history model in the order Palmariales. A consequence of this pattern is that the females mature very quickly (days to weeks) whereas the males take a whole year and fertilize the females from the current year.
