Research on ecology of intertidal mudflats in the upper Bay of Fundy. These areas provide critical foraging habitat during migration stopovers by Semipalmated Sandpipers and other shorebirds during their annual late-summer migration from the Canadian Arctic to South America. Predation by shorebirds can have a substantial effect on these mudflats, and offers an excellent opportunity to study community-level interactions. Further, mudflat communities are dynamic, with changes in species composition, interactions, and sediment characteristics occurring regularly. This has conservation implications for foraging shorebirds. By understanding mechanisms behind these changes, and responses of community members, we may be able to predict effects of further human-induced changes on the system.
I also study community dynamics on salt and freshwater marshes. Research interests include marsh restoration, habitat use by waterfowl, and community-level interactions between different species within marshes.

In the Upper Bay of Fundy, the presence of these diatoms is of importance to the mudflat keystone species Corophium volutator, and possibly other animals, for two reasons. Diatoms increase stability of surface sediments through the production of polysaccharide exudates and act as a food source for benthic fauna. Mobile diatoms in particular produce copious amounts of sediment binding polysaccharides.

The structure and composition of Fundy mudflat diatom communities is virtually unknown. Most research to date focused on the role of epipelic diatoms in sediment stabilization. Our own research addresses a different aspect of mudflat diatom ecology. First we are interested in the factors shaping the community structure of mudflat (tychoplanktonic, epipsammic and epipelic) diatoms. In particular, we are interested in the relationship between the mineral composition of the flats sediments and the diatom flora composition.

• Possible impacts of sea-level rise on the Northumberland Strait coast of New Brunswick (Cape Jourimain is one of the test sites for this study).
• Collaboration on assessing seasonal variations in the beach and foredune system at Greenwich Dunes, Prince Edward Island National Park.
• Collaboration with Ducks Unlimited Canada and other partners on a major marsh restoration project in Musquash, NB.

• Forests and trees in island watersheds; the interactions between people, trees and forests in selected Caribbean watersheds.
• Human influences on the ecology of Philippine mangrove forests. This research examines patterns of local resource use (selective cutting and tree planting) and their ecological effects on mangrove forests in the Philippines.
• Event Ecology: I have developed in collaboration with Andrew Vayda (Rutgers University) a novel methodology for analyzing human-environment interactions. This method has been field-tested by us in the Caribbean, Philippines and Indonesia.

Bouchard JN, Roy S, Ferreyra G, Campbell DA & Curtosi A (2005) Ultraviolet-B effects on photosystem II efficiency of natural phytoplankton communities from Antarctica. Polar Biology, 28: 607–618

Bouchard JN, Campbell DA & Roy S (2005) Effects of Ultraviolet-B radiation on the D1 protein repair cycle of natural phytoplankton communities from three latitudes (Canada, Brazil, Argentina). Journal of Phycology, 41: 273-286

Brown CM, Lawrence JE, Campbell DA (2006) Are phytoplankton population density maxima predictable through analysis of host and viral genomic DNA content? Journal of Marine Biology Research 86: 491-498

Burns RA, MacKenzie TDB & Campbell DA (2006) Inorganic carbon repletion constrains steady-state light acclimation in the cyanobacterium Synechococcus elongatus. Journal of Phycology, 42:610-621

Krauss, G., K.R. Sridhar, K. Jung, R. Wennrich, J. Ehrman and F. Baerlocher. 2003. Aquatic hyphomycetes in polluted groundwater habitats of Central Germany. Microbial Ecology 45: 329-339.

MacDonald TM, Dubois L, Smith LC, Campbell DA (2003) Sensitivity of Cyanobacterial Antenna, Reaction Center and CO2 Assimilation Transcripts and Proteains to Moderate UVB: Light Acclimation Potentiates Resistance to UVB. Photochemistry and Photobiology 77(4): 405-412

MacKenzie TDB, Johnson JM & Campbell DA (2005) Inorganic carbon acclimation in Synechococcus elongatus alters the dynamics of macromolecular pools and photosynthetic flues in response to increased light. Photosynthesis Research 85: 341 - 357

MacKenzie TDB & Campbell DA (2005) Cyanobacterial acclimation to rapidly fluctuating light is constrained by inorganic carbon status. Journal of Phycology, 41(4):801-811

MacKenzie TDB, Johnson JM, Cockshutt AM, Burns RA, Campbell DA (2005) Large reallocations of carbon, nitrogen and photosynthetic reductant among phycobilisomes, photosystems and Rubisco during light acclimation in Synechococcus elongatus are constrained in cells under low environmental inorganic carbon. Archives of Microbiology, 183: 190 - 202

Mackenzie TDB, Johnson J & Campbell DA (2004) Environmental change provokes apid macromolecular reallocations in a static population of photobionts in the lichen Lobaria pulmonaria. Lichenologist 36:425-433

MacKenzie TDB, Burns RA & Campbell DA (2004) Carbon status constrains light acclimation in the cyanobacterium Synechococcus elongatus. Plant Physiology 136: 3301-3312

McGinn PJ, Jones MJ, Macdonald AB, Campbell DA (2005) Light is required for low-CO2 mediated induction of transcripts encoding components of the CO2 -concentrating mechanism in the cyanobacterium Synechococcus elongatus: Analysis by quantitative reverse transcription - polymerase chain reaction (Q-RT-PCR). Canadian Journal of Botany, 83: 711-720

Mills, K.E and I. Kaczmarska. 2006. Autogamic reproductive behaviour and sex cell structure of Thalassiosira angulata. Botanica Marina 49: 417-430.

Mossman, D.J., G. Eigendorf, D. Tokaryk, F. Gauthier-Lafaye, K.D. Guckert, V. Melezhik and C.E.G. Farrow. 2003. Testing for fullerenes in geological material: Oklo carbonaceous substances, Karelian shungites, Sudbury “Black Tuff”. Geology 31: 255-258.

Nikolcheva LG & Baelocher F (2004) Taxon-specific fungal primers reveal unexpectedly high diversity during leaf decomposition in a stream. Mycological Progress 3(1): xxx-xxx

Nikolcheva LG & Baelocher F (2002) Phylogeny of Tetracladium based on 18S rDNA. Czecil Mycol 53(1): 285-295

Pitcher AM, Ollerhead J, Kellman L, Risk D, Campbell DA (2005) Evidence for Subsurface Pooling of CH4 in Saltmarsh Sediments in the Musquash Estuary, New Brunswick. Canadian Coastal Conference 2005.

Schofield SC, Campbell DA, Funk C, MacKenzie TDB (2003) Changes in macromolecular allocation in nondividing algal symbionts allow for photosynthetic acclimation in the lichen Lobaria pulmonaria. New Phytologist 10???: xxx-xxx

Sicora CI, Appleton SE, Brown CM, Chung J, Chandler J, Vass I & Campbell DA (2006) Cyanobacterial psbA families in Anabaena and Synechocystis encode trace, constitutive and UVB induced D1 isoforms. Biochimica et Biophysica Acta 1757:47-56

Stewart JM, Woods AK & Blakely JA (2005) Maxima Maximal enzyme activities, myoblobin and glutathione concentrations in heart, liver and skeletal muscle of the Northern Short-tailed shrew (Blarina brevicauda; Insectivora: Soricidae) Comparative Biochemistry Physiology Part B 141: 267-273

Stewart JM, Blakely JA, Karpowicz PA, Kalanxhi E, Thatcher BJ, Martin BM (2004) Unusually weak oxygen binding, physical properties, partial sequence, autoxidation rate and a potential phosphorylation site of beluga whale (Delphinapterus leucas) myoglobin. Comparative Biochemistry and Physiology Part B 137: 401-412

Sveshnikov D, Ensminger I, Ivanov AG, Campbell DA, Funk C, Jansson S, Lloyd J & Öquist G (2005) Photosynthetic responses to cold acclimation, freezing stress and recovery in Scots pine (Pinus sylvestris L.) seedlings under high and low light. Tree Physiology 26: 325-336

Trites, M., I. Kaczmarska, P.W. Hicklin, J.M. Ehrman and J. Ollerhead. 2005. Benthic diatoms from two mudflats in Chignecto Bay, Upper Bay of Fundy. Hydrobiologia 544: 299-319.

Trites, M., P. Hicklin, J. Ollerhead and I. Kaczmarska. 2004. Benthic diatoms from two intertidal mudflats in the Upper Bay of Fundy. In: Wells, P.G., G.R. Daborn, J.A. Persy, J. Harvey and S.J. Rolson (eds.), Health of the Bay of Fundy: Assessing Key Issues. Proceedings of the 5th BoF Science Workshop and Coastal Forum, Wolfville, N.S. May 13-16, 2002. Environment Canada – Atlantic Region Occasional Reports 21: 200-207.

Trites, Marsha. 2002. Community structure and abundance of the benthic diatoms in two mudflats in Chignecto Bay. Mount Allison University, Sackville, N.B., 93 pp.